Refractory Cavernous Sinus Thrombophlebitis Complicated by Brain Abscess and Infectious Hydrocephalus: A Case Report

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Its management becomes exceptionally challenging when complicated by intracranial abscesses, hydrocephalus, and multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). Case presentation: We report a case of a 52-year-old woman with poorly controlled diabetes and chronic alcohol use, who presented with headache, fever, and ocular symptoms. Initial neuroimaging suggested sinusitis and ischemic lesions. Metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) detected Staphylococcus aureus. Despite comprehensive antimicrobial therapy (including meropenem, vancomycin, and linezolid), anti-inflammatory treatment, and anticoagulation, her clinical course deteriorated with the development of brain and lung abscesses, cerebral infarction, and obstructive hydrocephalus. Serial CSF cultures grew MRSA alongside other organisms (Pantoea agglomerans, MRSE, Streptococcus salivarius). Multidisciplinary management led to external ventricular drainage and, ultimately, intraventricular vancomycin administration via an Ommaya reservoir, which achieved CSF sterilization. A ventriculoperitoneal shunt was subsequently placed, with sustained clinical improvement. Conclusions: This case illustrates the severe and refractory nature of MRSA-associated CST with intracranial complications. It highlights the diagnostic challenges posed by atypical presentations and polymicrobial infections, and underscores the critical limitations of systemic antibiotics in penetrating the central nervous system. The successful outcome was contingent upon a proactive, multidisciplinary strategy that included timely surgical intervention and the strategic use of intraventricular antimicrobial therapy to overcome the blood-brain barrier. This report emphasizes the importance of dynamic monitoring, personalized treatment escalation, and integrated team-based care in managing such complex infections. cavernous sinus thrombophlebitis brain abscess hydrocephalus methicillin-resistant Staphylococcus aureus (MRSA) multidisciplinary team intraventricular antimicrobial therapy Figures Figure 1 Figure 2 Figure 3 Introduction Cavernous sinus thrombosis (CST) is a rare yet life-threatening infectious thrombophlebitis, with an estimated incidence of 0.2–1.6 per 100,000 individuals[ 1 ]. Although advancements in diagnosis and management have significantly reduced its mortality rate to approximately 11%, associated morbidity remains considerable, with a disability rate of around 15%[ 2 ]. The clinical presentation of CST is closely linked to its unique anatomical location, typically featuring systemic signs of infection—such as fever and headache—along with characteristic ocular manifestations, including ophthalmoplegia, proptosis, and visual impairment[ 3 ]. The etiology of CST is predominantly infectious, most commonly arising from the contiguous spread of infections originating in the facial "danger triangle," paranasal sinuses, odontogenic foci, or otomastoid regions[ 3 , 4 ]. Non-infectious etiologies are relatively uncommon and may include malignancies (e.g., oral squamous cell carcinoma)[ 5 ], pharmacological factors (such as high‑dose corticosteroid therapy following COVID‑19) [ 6 ], surgical or traumatic events[ 7 ], and underlying hypercoagulable states[ 4 ]. Despite well-documented classic features, recognition of CST in clinical practice is often delayed. Management becomes substantially more challenging when CST is complicated by intracranial abscesses or infectious hydrocephalus, particularly when caused by multidrug-resistant organisms (MDROs) such as methicillin-resistant Staphylococcus aureus (MRSA). The treatment of such complex cases is prolonged and necessitates close multidisciplinary collaboration among neurology, neurosurgery, infectious diseases, ophthalmology, and neuroradiology specialists. However, systematic treatment strategies and shared clinical experiences regarding such refractory, complicated CST cases involving MDROs remain inadequately represented in the literature. Therefore, this report presents a case of refractory CST caused by MRSA, further complicated by brain abscess and infectious hydrocephalus. We aim to detail the diagnostic challenges, multidisciplinary decision-making process, and clinical outcomes in this case, with the goal of enhancing clinician awareness of complex central nervous system infections and underscoring the pivotal role of integrated multidisciplinary care in improving patient prognosis. Case presentation A 52-year-old woman was admitted on August 19, 2025, with a 9-day history of headache and a 5-day history of fever. Her symptoms began after an upper respiratory infection, initially featuring a right-sided pulsating headache and bilateral ocular distension that disrupted sleep. An outside brain MRI showed bilateral frontal-parietal subcortical ischemic lesions and sinusitis, with no relief from ibuprofen. Subsequently, she developed diplopia, right eye abduction limitation, and was diagnosed with ophthalmoplegia. Five days prior to admission, high-grade fever (Tmax 39.8°C), chills, bilateral ocular redness with discharge, and cough emerged. External labs showed leukocytosis (WBC 10.03×10⁹/L) and elevated CRP (167.11 mg/L). CT imaging revealed a left breast nodule and multiple pulmonary nodules (metastasis vs. inflammatory granulomas). Ceftriaxone therapy was ineffective. Upon outpatient evaluation at our hospital one day before admission, inflammatory markers had worsened (WBC 16.76×10⁹/L, CRP 191.6 mg/L). She experienced transient confusion during fever spikes. Although ertapenem administration partially improved her diplopia and headache, fever persisted, prompting admission. Since onset, she reported poor sleep, appetite, and a 5-kg weight loss. Past medical history included irregularly managed hypertension, penicillin allergy, and recently diagnosed diabetes and hyperlipidemia. Family history was positive for hypertension. Admission examination showed lethargy, bilateral periorbital erythema and edema (left eye closed with discharge), a firm, non-tender left breast nodule, and coarse breath sounds. Vital signs included tachycardia (107 bpm) and elevated blood pressure (153/93 mmHg). Laboratory Findings Hematology : Complete blood count showed leukocytosis (WBC 18.06 × 10⁹/L) with neutrophilia (14.82 × 10⁹/L) and a left shift (16% band forms, 63% segmented neutrophils). Hemoglobin was 108 g/L, and platelet count was 213 × 10⁹/L. Inflammatory and Coagulation Markers : Marked elevation of C-reactive protein (98.3 mg/L) and erythrocyte sedimentation rate (102 mm/h) was noted. Procalcitonin was 1.05 ng/mL, and D-dimer was 786 ng/mL. Biochemistry : Liver enzymes were mildly elevated (ALT 67 U/L, AST 95 U/L). Hypokalemia was present (potassium 2.94 mmol/L). Arterial Blood Gas : Indicated type I respiratory failure (PaO₂ 52 mmHg, PaCO₂ 33 mmHg). Cerebrospinal Fluid Analysis : Opening pressure was 105 mmH₂O. The CSF was clear and acellular. Analysis revealed pleocytosis (97 cells/µL; 91% mononuclear cells), hypoglycorrhachia (glucose 2.99 mmol/L), elevated protein (0.86 g/L), and chloride of 118.5 mmol/L. Metagenomic next-generation sequencing (mNGS) detected Staphylococcus aureus (1 sequence read). Other microbiological studies—including respiratory pathogen PCR panel, T-SPOT.TB, (1,3)-β-D-glucan, galactomannan, blood cultures, and blood mNGS—were negative. Imaging Findings Orbital CT (Fig. 1 A-C): Demonstrated bilateral proptosis and periorbital edema, dilated superior ophthalmic veins (left > right), and inflammatory changes in the maxillary, ethmoid, and sphenoid sinuses. The suprasellar and interpeduncular cisterns were poorly defined. Brain MRI with Contrast (Fig. 2A-D): Revealed: 1) Abnormal signal in the ambient and suprasellar cisterns, suggestive of inflammation/early abscess formation, extending to the left cerebral peduncle and pons; 2) Heterogeneous enhancement and enlargement of the right cavernous sinus, consistent with thrombosis; 3) Diffusion-restricting lesions in the bilateral basal ganglia, indicative of cerebritis or lacunar infarcts. Orbital MRI (Fig. 1 D-F): Confirmed bilateral proptosis and dilated superior ophthalmic veins, suggesting thrombophlebitis, alongside inflammatory changes in the left orbital soft tissues. Whole-body PET/CT (Fig. 3 ): Showed multiple hypermetabolic foci in the brain and lungs, suggestive of infectious processes. Findings were consistent with paranasal sinusitis. A left breast nodule demonstrated low FDG uptake, likely benign. Clinical Course and Management 1. Initial Management Based on high fever, headache, altered mentation, and ocular findings, the initial working diagnosis was infectious, including intracranial infection and possible endophthalmitis, with concurrent sepsis. Contrast-enhanced brain MRI subsequently confirmed cavernous sinus thrombophlebitis complicated by brain abscess, painful ophthalmoplegia, and bilateral orbital cellulitis. Antimicrobial therapy with intravenous meropenem (2g every 8h) was initiated on August 19. Vancomycin (1g every 12h) was added from August 22 to 27 after cerebrospinal fluid (CSF) metagenomic next-generation sequencing suggested Staphylococcus aureus . Adjunctive treatments included methylprednisolone (40mg daily, August 24–28), low-molecular-weight heparin (4000 IU daily), and mannitol. The patient became afebrile with improving inflammatory markers (Table 1), although headache persisted. Table 1. Serial laboratory findings of the patient: complete blood count and inflammatory markers Date WBC (×10⁹/L) NE ( × 10⁹/L) HB (g/L) PLT ( × 10⁹/L) CRP (mg/L) ESR (mm/h) PCT ( μ g/L) FER ( μ g/L) D-D ( μ g/L) 2025/8/19 18.06 14.82 108 213 98.3 102 1.05 4123 786 2025/8/25 10.39 7.55 96 424 7.6 108 0.174 – 309 2025/8/29 9.09 7.41 93 351 0.8 73 – 1331 196 2025/9/4 4.06 3.26 93 154 0.6 103 0.101 1291 309 2025/9/7 4.67 2.94 89 131 – 91 – 1189 158 2025/9/28 4.96 3.28 82 162 <0.5 55 – – 116 2025/10/2 3.01 1.70 73 112 <0.5 58 – – 152 2025/10/5 3.34 2.02 68 102 <0.5 50 – – 82 2025/10/8 4.86 2.96 66 150 <0.5 – – – 77 Abbreviations: WBC, white blood cell count; NE, neutrophil count; HB, hemoglobin; PLT, platelet count; CRP, C‑reactive protein; ESR, erythrocyte sedimentation rate; PCT, procalcitonin; FER, ferritin; D‑D, D‑dimer; –, not tested. 2. Disease Progression On August 26, the patient developed left limb weakness and dysarthria. MRI showed new diffusion-restricting lesions in the bilateral basal ganglia, consistent with cerebral infarction, possibly from septic embolism (Fig. 2E-H). Limb strength partially recovered with supportive care. Despite a therapeutic vancomycin trough (23.12 µg/mL), clinical response was suboptimal. Suspecting inadequate CNS penetration, vancomycin was switched to linezolid (600mg every 12h) on August 27. 3. Neurological Decline and Hydrocephalus On September 10–11, she experienced hallucinations, memory loss, urinary and fecal incontinence, gait instability, and amnesia. CT revealed marked ventricular enlargement indicative of hydrocephalus (Fig. 1 G-I). Multidisciplinary consensus recommended continued antibiotics and ventricular drainage. She underwent Ommaya reservoir placement and external ventricular drainage on September 19. 4. Treatment Adjustment and Persistent Infection Post-operative neurological function improved. While CRP normalized and ESR trended down, hemoglobin and platelets declined, attributed to linezolid. Linezolid was replaced with vancomycin on October 5, with subsequent hematological recovery (Table 1). After two months of antibiotics, CSF parameters improved but cultures remained positive, growing MRSA, Pantoea agglomerans , MRSE, and Streptococcus salivarius (Table 2 ). A subsequent MDT review led to the decision for intraventricular therapy. The patient was transferred to a tertiary neurosurgical center on October 23, where the Ommaya reservoir was removed and an external ventricular drain placed for intraventricular Vancomycin administration. Table 2 Serial cerebrospinal fluid (CSF) analysis and microbiological findings Date WBC [0–8] RBC Glucose (mmol/L) [2.5–4.5] Protein (g/L) [0.15–0.45] Chloride (mmol/L) [120–132] Pathogen Identified 2025/8/27* 97 0 2.99 0.88 118 Staphylococcus aureus (mNGS) 2025/9/19 63 13 3.64 0.53 119 No growth 2025/9/23 44 110 3.63 0.97 122.8 Methicillin-resistant S. aureus (MRSA) 2025/9/26 0 30 3.54 0.7 121 MRSA 2025/9/29 8 130 4.32 0.49 122.9 MRSA 2025/10/3 3 35 3.27 0.51 122.2 Pantoea agglomerans 2025/10/7 4 0 3.85 0.42 125.3 Methicillin-resistant Staphylococcus epidermidis (MRSE) 2025/10/10 3 0 3.89 0.36 128.6 MRSA 2025/10/14 2 0 3.94 0.32 129.5 Streptococcus salivarius 2025/10/15* 7 0 3.23 0.68 125.5 Bacillus subtilis 2025/10/18 3 0 3.88 0.33 127.4 Streptococcus sanguinis Footnotes : Abbreviations: WBC, white blood cell count; RBC, red blood cell count; mNGS, metagenomic next-generation sequencing; MRSA, methicillin-resistant Staphylococcus aureus; MRSE, methicillin-resistant Staphylococcus epidermidis. “*” indicates results from lumbar puncture CSF specimens; all other data represent CSF samples obtained from the external ventricular drain. 5. Follow-up and Definitive Surgery According to the patient’s clinical follow-up records from the external institution, CSF cultures and a targeted next-generation sequencing assay were reported as negative by November 12. A ventriculoperitoneal shunt was successfully placed on December 11, with sustained clinical improvement. The patient remains under follow-up. Discussion The management of this patient with refractory MRSA-related CST, complicated by brain abscess and infectious hydrocephalus, underscores the formidable diagnostic and therapeutic challenges posed by complex, multidrug-resistant central nervous system (CNS) infections. Our experience crystallizes several critical dilemmas: navigating ambiguous initial presentations, overcoming the blood-brain barrier to deliver effective antimicrobial therapy, and determining the optimal timing for procedural interventions within a multidisciplinary framework. 1. Comorbidities and Clinical Vigilance The patient’s background of poorly controlled diabetes, exacerbated by chronic alcohol use, is a salient feature. Diabetes, particularly when uncontrolled, can heighten susceptibility to severe infections and impede immune response. A retrospective study of 88 CST patients noted that 34% had comorbidities associated with immunosuppression, including diabetes and chronic alcohol abuse[ 2 ]. This aligns with our case and underscores the need for heightened clinical suspicion for CST in patients with such risk factors who present with compatible symptoms. Furthermore, an immunocompromised state may elevate the risk of fungal co-infection, warranting thorough microbiological investigation and consideration of broader empirical coverage in selected cases[ 3 ]. 2. Navigating Diagnostic Ambiguity The diagnosis was delayed due to multiple overlapping challenges. First, the non-specific clinical presentation —fever, headache, altered mental status, ocular proptosis, and diplopia—initially suggested more common conditions such as acute glaucoma or orbital cellulitis[ 4 , 7 , 8 ]. The key diagnostic clue emerged from the concurrent presence of altered consciousness and painful ophthalmoplegia , a combination that should immediately prioritize CST in the differential diagnosis as it localizes pathology to both the intracranial space and the cavernous sinus. Second, identifying the infectious source was obscure in the absence of typical portals like facial lesions or overt sinusitis. As previously noted, common infectious sources for CST encompass facial skin infections, sinusitis (particularly involving the sphenoid or ethmoid sinuses), dental procedures, otitis media or mastoiditis, and orbital cellulitis, among others[ 1 ]. The history of a subcutaneous injection near the temporal artery raised the possibility of an iatrogenic origin, highlighting that procedural history is crucial in seemingly cryptogenic cases. Third, microbiological complexity added to the challenge. While initial CSF metagenomic sequencing suggested Staphylococcus aureus , subsequent cultures revealed a polymicrobial profile including MRSA, Pantoea agglomerans , MRSE, and Streptococcus salivarius . This could represent true polymicrobial infection or sequential catheter colonization, a known confounding factor in CST diagnostics[ 9 ]. The confirmed presence of MRSA necessitated a dedicated antimicrobial strategy accounting for CNS penetration and resistance. Finally, early neuroimaging was inconclusive. Definitive diagnosis was achieved through dedicated orbital MRI, which demonstrated bilateral superior ophthalmic vein (SOV) dilation and right cavernous sinus enlargement—findings consistent with established radiological criteria that report high sensitivity and specificity for SOV dilation ≥ 2.9 mm in CST[ 10 ]. 3. Therapeutic Decision-Making in a Complex Case Management required navigating several interlinked therapeutic dilemmas. Antimicrobial Strategy and the Blood-Brain Barrier The initial use of intravenous vancomycin, despite therapeutic serum trough levels, failed to sterilize the CSF and was followed by new cerebral infarcts, possibly from septic emboli. Switching to linezolid offered superior tissue penetration but was limited by myelosuppression. This sequence underscores the critical limitation of systemic antibiotics in achieving therapeutic CNS concentrations and argues for the early consideration of therapeutic drug monitoring (TDM). The eventual CSF sterilization was achieved only after the administration of intraventricular vancomycin via an Ommaya reservoir, directly bypassing the blood-brain barrier. This supports the paradigm that direct intrathecal therapy should be a proactive consideration in culture-positive, refractory CNS infections, rather than a last resort[ 11 ]. Anticoagulation Management Therapeutic anticoagulation with low-molecular-weight heparin was initiated for the septic thrombosis. The subsequent need for neurosurgical intervention due to hydrocephalus required a careful, ongoing risk-benefit assessment regarding bleeding. Our decision to continue anticoagulation is supported by meta-analytic data suggesting a significant mortality benefit with anticoagulation in CST (3.3% vs. 18%, p = 0.022) [ 12 ]. Surgical Intervention and Source Control External ventricular drainage and Ommaya reservoir placement were initially performed to manage obstructive hydrocephalus. However, the persistence of positive CSF cultures despite optimal systemic antimicrobial therapy indicated either inadequate central nervous system drug penetration or a persistent localized infection. Otorhinolaryngological evaluation excluded surgical indications for sinusitis as a primary source. This scenario raised a critical differential diagnosis among true ongoing infection, specimen contamination, and catheter colonization. In this context, a study from the University Hospital Munich, Germany, is informative; it reported that while most biochemical markers from external ventricular drain (EVD) fluid show consistency between distal and proximal samples, cell counts and cytology remain reliant on proximal sampling[ 13 ]. This suggests that biochemical parameters from drainage fluid retain diagnostic relevance. Given the suboptimal response to systemic therapy and the need to address a likely localized infectious nidus, the multidisciplinary team decided to escalate therapy. Consequently, intraventricular antibiotic administration was employed as a definitive, targeted strategy, aligning with the principle that in complicated CST, direct intervention—whether surgical drainage of collections or, as in this case, direct antimicrobial delivery—is crucial for source control[ 14 ]. The Imperative of Multidisciplinary Collaboration This case exemplifies that optimal outcomes in complex CST are unattainable without seamless multidisciplinary team (MDT) integration. Coordinated input from neurology, neurosurgery, infectious diseases, ophthalmology, and otolaryngology was indispensable for diagnostic synthesis, timing of procedures, antimicrobial stewardship, and monitoring of complications. The literature strongly supports that such an MDT approach facilitates earlier diagnosis, personalized treatment, and improved outcomes, especially in atypical presentations[ 6 ]. 4. Clinical Implications This case yields several practical insights. First, it reinforces that diabetes and chronic alcohol use are significant risk modifiers that should lower the threshold for investigating CST. Second, it highlights iatrogenic procedures as a potential, though often overlooked, portal of entry for devastating CNS infections, mandating strict aseptic technique. Third, it demonstrates that intraventricular antibiotic therapy can be decisive in overcoming pharmacokinetic barriers in refractory cases. Finally, it validates a structured MDT framework as the standard of care for managing CST with neurological complications. Limitations Our report has limitations inherent to a single case study. The precise origin of infection (iatrogenic vs. subclinical sinusitis) remains undetermined. While managed effectively, the potential for the indwelling Ommaya reservoir to contribute to biofilm-related persistence cannot be entirely excluded. Additionally, key follow-up laboratory data (including the CSF tNGS result from November 12, 2025) were obtained from an external institution, limiting our ability to independently verify the original data and detailed methodological parameters. Long-term neurological follow-up is required to assess for potential sequelae such as chronic cranial nerve deficits. Conclusion In conclusion, this refractory case of MRSA CST with intracranial complications illustrates that successful outcomes depend on synthesizing subtle clinical clues, escalating decisively to direct CNS drug delivery when systemic therapy fails, and integrating multidisciplinary expertise from the outset. It serves as a salient reminder that in at-risk patients, CST must be considered promptly to mitigate its high morbidity, and that management often necessitates moving beyond conventional therapeutic paradigms to include innovative and targeted approaches. Abbreviations CST Cavernous sinus thrombophlebitis MRSA methicillin-resistant Staphylococcus aureus mNGS Metagenomic next-generation sequencing CSF cerebrospinal fluid MDROs multidrug-resistant organisms WBC white blood cell count NE neutrophil count HB hemoglobin PLT platelet count CRP C‑reactive protein ESR erythrocyte sedimentation rate PCT procalcitonin FER ferritin D‑D D‑dimer CNS central nervous system TDM therapeutic drug monitoring SOV superior ophthalmic vein EVD external ventricular drain MDT multidisciplinary team Declarations Ethics approval and consent to participate This case report was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval for this study was obtained from the Peking University People's Hospital. Written informed consent was obtained from the patient for participation in this study. Consent for publication Written informed consent was obtained from the patient for publication of this case report and any accompanying images. Availability of data and materials The raw metagenomic sequencing data generated during this study are available in the National Genomics Data Center (NGDC) Genome Sequence Archive (GSA) repository under BioProject accession number PRJCA055011 (https://ngdc.cncb.ac.cn/bioproject/browse/PRJCA055011). The data are currently under private access and will be made publicly available upon publication of this article. All other clinical data (including medical records and imaging studies) supporting the findings of this study are available within the article, or from the corresponding author on reasonable request, subject to privacy and ethical restrictions. Competing interests The authors declare that they have no competing interests. Funding This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Authors' contributions Yuanyuan Chen conceptualized the study, determined the report’s significance, collected and organized patient data (including imaging and laboratory results), performed the literature review, and drafted the initial manuscript. Jiacheng Liu and Song Wang were responsible for data curation and verified the accuracy of the data. Qingpei Hao contributed surgical data curation and provided clinical resources. Xia Liu performed imaging analysis and provided supervisory support. Yan Gao critically reviewed and edited the manuscript and provided overall supervision of the project. All authors read and approved the final manuscript. Acknowledgements The authors would like to thank the patient for agreeing to the publication of this case. We thank Associate Researcher Yunyao Yin from the Department of Clinical Laboratory, Peking University People's Hospital, for providing the mNGS data and her expertise in microbiological analysis. We also thank the nursing staff of the Department of Neurosurgery for their dedicated patient care. References Caranfa JT, Yoon MK. Septic cavernous sinus thrombosis: A review. Surv Ophthalmol. 2021;66(6):1021–30. Weerasinghe D, Lueck CJ. Septic Cavernous Sinus Thrombosis: Case Report and Review of the Literature. Neuroophthalmology. 2016;40(6):263–76. Housley SB, McPheeters MJ, Raygor KP, Bouslama M, Scullen T, Davies JM. Cavernous Sinus Thrombosis. Neurosurg Clin N Am. 2024;35(3):305–10. Ali S. Cavernous Sinus Thrombosis: Efficiently Recognizing and Treating a Life-Threatening Condition. Cureus. 2021;13(8):e17339. Sultania M, Das Majumdar SK, Raghuram K, Ganapathy A. A rare case of cavernous sinus thrombosis following oral squamous cell carcinoma - The etiology and management dilemma. Oral Oncol. 2023;142:106421. Karakeçili F, Barkay O, Sümer B, Binay UD, Memiş KB, Yapıcıer Ö, Balcı MG. Invasive Aspergillosis with Cavernous Sinus Thrombosis Following High-Dose Corticosteroid Therapy: A Challenging Case of Rhino-Orbital-Cerebral Mycosis. J Fungi (Basel) 2024, 10(11). Kim J-M, Kang KW, Kim H, Lee S-H, Kim T-S, Park M-S. Septic cavernous sinus thrombosis after minor head trauma: A case report. Med (Baltim). 2022;101(10):e29057. Fujikawa T, Sogabe Y. Septic cavernous sinus thrombosis: potentially fatal conjunctival hyperemia. Intensive Care Med. 2018;45(5):692–3. Geng B, Wu X, Malhotra A. Septic cavernous sinus thrombosis-Case series and review of the literature. Clin Neurol Neurosurg. 2020;197:106092. Bhatia H, Kaur R, Bedi R. MR imaging of cavernous sinus thrombosis. Eur J Radiol Open. 2020;7:100226. Bodilsen J, D'Alessandris QG, Humphreys H, Iro MA, Klein M, Last K, Montesinos IL, Pagliano P, Sipahi OR, San-Juan R, et al. European society of Clinical Microbiology and Infectious Diseases guidelines on diagnosis and treatment of brain abscess in children and adults. Clin Microbiol Infect. 2023;30(1):66–89. Akarapas C, Wiwatkunupakarn N, Sithirungson S, Chaiyasate S. Anticoagulation for cavernous sinus thrombosis: a systematic review and individual patient data meta-analysis. Eur Arch Otorhinolaryngol. 2024;282(3):1127–34. Kinast CB, Paal M, Liebchen U. Comparison of Cerebrospinal Fluid Collection Through the Proximal and Distal Port Below the Overflow System from an External Ventricular Drain. Neurocrit Care. 2022;37(3):775–8. van der Poel NA, Mourits MP, de Win MML, Coutinho JM, Dikkers FG. Prognosis of septic cavernous sinus thrombosis remarkably improved: a case series of 12 patients and literature review. Eur Arch Otorhinolaryngol. 2018;275(9):2387–95. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 24 Apr, 2026 Read the published version in BMC Infectious Diseases → Version 1 posted Editorial decision: Revision requested 04 Feb, 2026 Reviews received at journal 17 Jan, 2026 Reviewers agreed at journal 15 Jan, 2026 Reviewers agreed at journal 10 Jan, 2026 Reviews received at journal 10 Jan, 2026 Reviewers agreed at journal 10 Jan, 2026 Reviewers agreed at journal 10 Jan, 2026 Reviews received at journal 10 Jan, 2026 Reviewers agreed at journal 10 Jan, 2026 Reviewers agreed at journal 09 Jan, 2026 Reviewers invited by journal 07 Jan, 2026 Editor assigned by journal 05 Jan, 2026 Submission checks completed at journal 03 Jan, 2026 First submitted to journal 03 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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15:08:24","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8449809/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8449809/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12879-026-13208-7","type":"published","date":"2026-04-24T15:59:49+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":100362210,"identity":"a31db2b7-dd29-448b-98a1-80344ba9b864","added_by":"auto","created_at":"2026-01-16 07:46:21","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":2936973,"visible":true,"origin":"","legend":"","description":"","filename":"RevisedManuscriptClean.docx","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/4ecb96271d6d36fa6bc68ade.docx"},{"id":100017720,"identity":"256803dd-039b-4f79-9e8f-063c083e6aaa","added_by":"auto","created_at":"2026-01-12 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07:11:22","extension":"xml","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":73785,"visible":true,"origin":"","legend":"","description":"","filename":"908f8697e93d40109bd718db95cb685b1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/b822d5f5b8852579979e4d7d.xml"},{"id":100017731,"identity":"ceff27a4-36fc-41f7-8b9b-2ad488575336","added_by":"auto","created_at":"2026-01-12 07:11:22","extension":"html","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":84639,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/b7a1cf161ef1d691b02c74fd.html"},{"id":100017723,"identity":"4188f77e-5fc0-47b8-b3e7-dadcb6a28393","added_by":"auto","created_at":"2026-01-12 07:11:21","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":610554,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA–C: Orbital CT (August 23).\u003c/strong\u003e Demonstrates bilateral proptosis and periorbital edema, dilation of the superior ophthalmic veins, and inflammatory opacification of the maxillary, ethmoid, and sphenoid sinuses. \u003cstrong\u003eD–F: Orbital MRI (August 23).\u003c/strong\u003e Confirms bilateral proptosis and dilation of the superior ophthalmic veins, suggestive of thrombophlebitis. Inflammatory changes are noted in the left orbital soft tissues. \u003cstrong\u003eG–I: Cranial CT (September 11).\u003c/strong\u003e Shows a slight regression of previous infectious/inflammatory changes. Marked enlargement of the third and bilateral lateral ventricles is evident, consistent with hydrocephalus.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/5d79142637c2d80236fa5441.png"},{"id":100017721,"identity":"4bdb8487-7ddb-4b5a-951f-0c9b91393370","added_by":"auto","created_at":"2026-01-12 07:11:21","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":573809,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA–D: Contrast-enhanced brain MRI (August 23).\u003c/strong\u003e Images demonstrate abnormal signal in the ambient and suprasellar cisterns, consistent with inflammatory change or early abscess formation, with extension to the left cerebral peduncle and pons. The right cavernous sinus is widened and shows heterogeneous enhancement, suggestive of thrombosis. Diffusion-weighted imaging (DWI) reveals hyperintense lesions in the bilateral basal ganglia. \u003cstrong\u003eE–H: Follow-up brain MRI (August 26).\u003c/strong\u003e Compared to the prior study, there is an interval increase in the number and extent of DWI hyperintense lesions within the bilateral basal ganglia.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/505128f1cc33eb98badcd5ab.png"},{"id":100017728,"identity":"dc6f5e90-6e9c-4082-95e4-85082fd97aa3","added_by":"auto","created_at":"2026-01-12 07:11:21","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1273327,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePET/CT findings.\u003c/strong\u003e Multiple hypermetabolic foci are present in the brain parenchyma, suggestive of infectious or inflammatory processes. Bilateral pulmonary nodules also demonstrate increased FDG uptake, consistent with probable infectious etiology. The study further reveals metabolic activity in the paranasal sinuses, compatible with sinusitis. A left breast nodule shows low-grade FDG avidity, likely benign without features indicating malignancy.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/f1f49bd957b6908e97310bcb.png"},{"id":107929591,"identity":"9ea12649-79ea-463d-ba2c-f63dffc08c63","added_by":"auto","created_at":"2026-04-27 16:19:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2789665,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8449809/v1/b2b58cd4-3528-42ba-b1aa-27e60419fcf9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Refractory Cavernous Sinus Thrombophlebitis Complicated by Brain Abscess and Infectious Hydrocephalus: A Case Report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCavernous sinus thrombosis (CST) is a rare yet life-threatening infectious thrombophlebitis, with an estimated incidence of 0.2\u0026ndash;1.6 per 100,000 individuals[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Although advancements in diagnosis and management have significantly reduced its mortality rate to approximately 11%, associated morbidity remains considerable, with a disability rate of around 15%[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The clinical presentation of CST is closely linked to its unique anatomical location, typically featuring systemic signs of infection\u0026mdash;such as fever and headache\u0026mdash;along with characteristic ocular manifestations, including ophthalmoplegia, proptosis, and visual impairment[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe etiology of CST is predominantly infectious, most commonly arising from the contiguous spread of infections originating in the facial \"danger triangle,\" paranasal sinuses, odontogenic foci, or otomastoid regions[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Non-infectious etiologies are relatively uncommon and may include malignancies (e.g., oral squamous cell carcinoma)[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], pharmacological factors (such as high‑dose corticosteroid therapy following COVID‑19) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], surgical or traumatic events[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], and underlying hypercoagulable states[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite well-documented classic features, recognition of CST in clinical practice is often delayed. Management becomes substantially more challenging when CST is complicated by intracranial abscesses or infectious hydrocephalus, particularly when caused by multidrug-resistant organisms (MDROs) such as methicillin-resistant \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (MRSA). The treatment of such complex cases is prolonged and necessitates close multidisciplinary collaboration among neurology, neurosurgery, infectious diseases, ophthalmology, and neuroradiology specialists. However, systematic treatment strategies and shared clinical experiences regarding such refractory, complicated CST cases involving MDROs remain inadequately represented in the literature.\u003c/p\u003e \u003cp\u003eTherefore, this report presents a case of refractory CST caused by MRSA, further complicated by brain abscess and infectious hydrocephalus. We aim to detail the diagnostic challenges, multidisciplinary decision-making process, and clinical outcomes in this case, with the goal of enhancing clinician awareness of complex central nervous system infections and underscoring the pivotal role of integrated multidisciplinary care in improving patient prognosis.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA 52-year-old woman was admitted on August 19, 2025, with a 9-day history of headache and a 5-day history of fever. Her symptoms began after an upper respiratory infection, initially featuring a right-sided pulsating headache and bilateral ocular distension that disrupted sleep. An outside brain MRI showed bilateral frontal-parietal subcortical ischemic lesions and sinusitis, with no relief from ibuprofen. Subsequently, she developed diplopia, right eye abduction limitation, and was diagnosed with ophthalmoplegia. Five days prior to admission, high-grade fever (Tmax 39.8\u0026deg;C), chills, bilateral ocular redness with discharge, and cough emerged. External labs showed leukocytosis (WBC 10.03\u0026times;10⁹/L) and elevated CRP (167.11 mg/L). CT imaging revealed a left breast nodule and multiple pulmonary nodules (metastasis vs. inflammatory granulomas). Ceftriaxone therapy was ineffective.\u003c/p\u003e \u003cp\u003eUpon outpatient evaluation at our hospital one day before admission, inflammatory markers had worsened (WBC 16.76\u0026times;10⁹/L, CRP 191.6 mg/L). She experienced transient confusion during fever spikes. Although ertapenem administration partially improved her diplopia and headache, fever persisted, prompting admission. Since onset, she reported poor sleep, appetite, and a 5-kg weight loss. Past medical history included irregularly managed hypertension, penicillin allergy, and recently diagnosed diabetes and hyperlipidemia. Family history was positive for hypertension.\u003c/p\u003e \u003cp\u003eAdmission examination showed lethargy, bilateral periorbital erythema and edema (left eye closed with discharge), a firm, non-tender left breast nodule, and coarse breath sounds. Vital signs included tachycardia (107 bpm) and elevated blood pressure (153/93 mmHg).\u003c/p\u003e\n\u003ch3\u003eLaboratory Findings\u003c/h3\u003e\n\u003cp\u003e \u003cb\u003eHematology\u003c/b\u003e: Complete blood count showed leukocytosis (WBC 18.06 \u0026times; 10⁹/L) with neutrophilia (14.82 \u0026times; 10⁹/L) and a left shift (16% band forms, 63% segmented neutrophils). Hemoglobin was 108 g/L, and platelet count was 213 \u0026times; 10⁹/L. \u003cb\u003eInflammatory and Coagulation Markers\u003c/b\u003e: Marked elevation of C-reactive protein (98.3 mg/L) and erythrocyte sedimentation rate (102 mm/h) was noted. Procalcitonin was 1.05 ng/mL, and D-dimer was 786 ng/mL. \u003cb\u003eBiochemistry\u003c/b\u003e: Liver enzymes were mildly elevated (ALT 67 U/L, AST 95 U/L). Hypokalemia was present (potassium 2.94 mmol/L). \u003cb\u003eArterial Blood Gas\u003c/b\u003e: Indicated type I respiratory failure (PaO₂ 52 mmHg, PaCO₂ 33 mmHg). \u003cb\u003eCerebrospinal Fluid Analysis\u003c/b\u003e: Opening pressure was 105 mmH₂O. The CSF was clear and acellular. Analysis revealed pleocytosis (97 cells/\u0026micro;L; 91% mononuclear cells), hypoglycorrhachia (glucose 2.99 mmol/L), elevated protein (0.86 g/L), and chloride of 118.5 mmol/L. Metagenomic next-generation sequencing (mNGS) detected \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (1 sequence read). Other microbiological studies\u0026mdash;including respiratory pathogen PCR panel, T-SPOT.TB, (1,3)-β-D-glucan, galactomannan, blood cultures, and blood mNGS\u0026mdash;were negative.\u003c/p\u003e\n\u003ch3\u003eImaging Findings\u003c/h3\u003e\n\u003cp\u003e \u003cb\u003eOrbital CT\u003c/b\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA-C): Demonstrated bilateral proptosis and periorbital edema, dilated superior ophthalmic veins (left\u0026thinsp;\u0026gt;\u0026thinsp;right), and inflammatory changes in the maxillary, ethmoid, and sphenoid sinuses. The suprasellar and interpeduncular cisterns were poorly defined. \u003cb\u003eBrain MRI with Contrast\u003c/b\u003e (Fig.\u0026nbsp;2A-D): Revealed: 1) Abnormal signal in the ambient and suprasellar cisterns, suggestive of inflammation/early abscess formation, extending to the left cerebral peduncle and pons; 2) Heterogeneous enhancement and enlargement of the right cavernous sinus, consistent with thrombosis; 3) Diffusion-restricting lesions in the bilateral basal ganglia, indicative of cerebritis or lacunar infarcts. \u003cb\u003eOrbital MRI\u003c/b\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD-F): Confirmed bilateral proptosis and dilated superior ophthalmic veins, suggesting thrombophlebitis, alongside inflammatory changes in the left orbital soft tissues. \u003cb\u003eWhole-body PET/CT\u003c/b\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e): Showed multiple hypermetabolic foci in the brain and lungs, suggestive of infectious processes. Findings were consistent with paranasal sinusitis. A left breast nodule demonstrated low FDG uptake, likely benign.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClinical Course and Management\u003c/b\u003e \u003c/p\u003e\n\u003ch3\u003e1. Initial Management\u003c/h3\u003e\n\u003cp\u003eBased on high fever, headache, altered mentation, and ocular findings, the initial working diagnosis was infectious, including intracranial infection and possible endophthalmitis, with concurrent sepsis. Contrast-enhanced brain MRI subsequently confirmed cavernous sinus thrombophlebitis complicated by brain abscess, painful ophthalmoplegia, and bilateral orbital cellulitis. Antimicrobial therapy with intravenous meropenem (2g every 8h) was initiated on August 19. Vancomycin (1g every 12h) was added from August 22 to 27 after cerebrospinal fluid (CSF) metagenomic next-generation sequencing suggested \u003cem\u003eStaphylococcus aureus\u003c/em\u003e. Adjunctive treatments included methylprednisolone (40mg daily, August 24\u0026ndash;28), low-molecular-weight heparin (4000 IU daily), and mannitol. The patient became afebrile with improving inflammatory markers (Table\u0026nbsp;1), although headache persisted.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eTable 1. Serial laboratory findings of the patient: complete blood count and inflammatory markers\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDate\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWBC (×10⁹/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNE (\u003c/strong\u003e\u003cstrong\u003e×\u003c/strong\u003e\u003cstrong\u003e10⁹/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHB (g/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePLT (\u003c/strong\u003e\u003cstrong\u003e×\u003c/strong\u003e\u003cstrong\u003e10⁹/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCRP (mg/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eESR (mm/h)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePCT (\u003c/strong\u003e\u003cstrong\u003eμ\u003c/strong\u003e\u003cstrong\u003eg/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eFER (\u003c/strong\u003e\u003cstrong\u003eμ\u003c/strong\u003e\u003cstrong\u003eg/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eD-D (\u003c/strong\u003e\u003cstrong\u003eμ\u003c/strong\u003e\u003cstrong\u003eg/L)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/8/19\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e14.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e108\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e213\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e98.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4123\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e786\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/8/25\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e10.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e424\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e108\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.174\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e309\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/8/29\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e9.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e351\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1331\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e196\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/9/4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e154\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e103\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1291\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e309\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/9/7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e158\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/9/28\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e116\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/10/2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e152\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/10/5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e2025/10/8\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e–\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e77\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eAbbreviations:\u003c/strong\u003e WBC, white blood cell count; NE, neutrophil count; HB, hemoglobin; PLT, platelet count; CRP, C‑reactive protein; ESR, erythrocyte sedimentation rate; PCT, procalcitonin; FER, ferritin; D‑D, D‑dimer; –, not tested.\u003c/p\u003e\n\u003ch3\u003e2. Disease Progression\u003c/h3\u003e\n\u003cp\u003eOn August 26, the patient developed left limb weakness and dysarthria. MRI showed new diffusion-restricting lesions in the bilateral basal ganglia, consistent with cerebral infarction, possibly from septic embolism (Fig.\u0026nbsp;2E-H). Limb strength partially recovered with supportive care. Despite a therapeutic vancomycin trough (23.12 \u0026micro;g/mL), clinical response was suboptimal. Suspecting inadequate CNS penetration, vancomycin was switched to linezolid (600mg every 12h) on August 27.\u003c/p\u003e\n\u003ch3\u003e3. Neurological Decline and Hydrocephalus\u003c/h3\u003e\n\u003cp\u003eOn September 10\u0026ndash;11, she experienced hallucinations, memory loss, urinary and fecal incontinence, gait instability, and amnesia. CT revealed marked ventricular enlargement indicative of hydrocephalus (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eG-I). Multidisciplinary consensus recommended continued antibiotics and ventricular drainage. She underwent Ommaya reservoir placement and external ventricular drainage on September 19.\u003c/p\u003e\n\u003ch3\u003e4. Treatment Adjustment and Persistent Infection\u003c/h3\u003e\n\u003cp\u003ePost-operative neurological function improved. While CRP normalized and ESR trended down, hemoglobin and platelets declined, attributed to linezolid. Linezolid was replaced with vancomycin on October 5, with subsequent hematological recovery (Table\u0026nbsp;1). After two months of antibiotics, CSF parameters improved but cultures remained positive, growing MRSA, \u003cem\u003ePantoea agglomerans\u003c/em\u003e, MRSE, and \u003cem\u003eStreptococcus salivarius\u003c/em\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e2\u003c/span\u003e). A subsequent MDT review led to the decision for intraventricular therapy. The patient was transferred to a tertiary neurosurgical center on October 23, where the Ommaya reservoir was removed and an external ventricular drain placed for intraventricular Vancomycin administration.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSerial cerebrospinal fluid (CSF) analysis and microbiological findings\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDate\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWBC [0\u0026ndash;8]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRBC\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGlucose (mmol/L) [2.5\u0026ndash;4.5]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eProtein (g/L) [0.15\u0026ndash;0.45]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eChloride (mmol/L) [120\u0026ndash;132]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePathogen Identified\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/8/27*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e118\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eStaphylococcus aureus\u003c/em\u003e\u0026nbsp;(mNGS)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/9/19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e119\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNo growth\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/9/23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e122.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMethicillin-resistant\u0026nbsp;\u003cem\u003eS. aureus\u003c/em\u003e\u0026nbsp;(MRSA)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/9/26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e121\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMRSA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/9/29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e122.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMRSA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e122.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ePantoea agglomerans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e125.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMethicillin-resistant\u0026nbsp;\u003cem\u003eStaphylococcus epidermidis\u003c/em\u003e\u0026nbsp;(MRSE)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e128.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMRSA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e129.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus salivarius\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/15*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e125.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eBacillus subtilis\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2025/10/18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e127.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus sanguinis\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e\u003cb\u003eFootnotes\u003c/b\u003e: Abbreviations: WBC, white blood cell count; RBC, red blood cell count; mNGS, metagenomic next-generation sequencing; MRSA, methicillin-resistant Staphylococcus aureus; MRSE, methicillin-resistant Staphylococcus epidermidis. \u0026ldquo;*\u0026rdquo; indicates results from lumbar puncture CSF specimens; all other data represent CSF samples obtained from the external ventricular drain.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003e5. Follow-up and Definitive Surgery\u003c/h3\u003e\n\u003cp\u003eAccording to the patient\u0026rsquo;s clinical follow-up records from the external institution, CSF cultures and a targeted next-generation sequencing assay were reported as negative by November 12. A ventriculoperitoneal shunt was successfully placed on December 11, with sustained clinical improvement. The patient remains under follow-up.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe management of this patient with refractory MRSA-related CST, complicated by brain abscess and infectious hydrocephalus, underscores the formidable diagnostic and therapeutic challenges posed by complex, multidrug-resistant central nervous system (CNS) infections. Our experience crystallizes several critical dilemmas: navigating ambiguous initial presentations, overcoming the blood-brain barrier to deliver effective antimicrobial therapy, and determining the optimal timing for procedural interventions within a multidisciplinary framework.\u003c/p\u003e\n\u003ch3\u003e1. Comorbidities and Clinical Vigilance\u003c/h3\u003e\n\u003cp\u003eThe patient\u0026rsquo;s background of poorly controlled diabetes, exacerbated by chronic alcohol use, is a salient feature. Diabetes, particularly when uncontrolled, can heighten susceptibility to severe infections and impede immune response. A retrospective study of 88 CST patients noted that 34% had comorbidities associated with immunosuppression, including diabetes and chronic alcohol abuse[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. This aligns with our case and underscores the need for heightened clinical suspicion for CST in patients with such risk factors who present with compatible symptoms. Furthermore, an immunocompromised state may elevate the risk of fungal co-infection, warranting thorough microbiological investigation and consideration of broader empirical coverage in selected cases[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\n\u003ch3\u003e2. Navigating Diagnostic Ambiguity\u003c/h3\u003e\n\u003cp\u003eThe diagnosis was delayed due to multiple overlapping challenges. First, the \u003cb\u003enon-specific clinical presentation\u003c/b\u003e\u0026mdash;fever, headache, altered mental status, ocular proptosis, and diplopia\u0026mdash;initially suggested more common conditions such as acute glaucoma or orbital cellulitis[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The key diagnostic clue emerged from the \u003cb\u003econcurrent presence of altered consciousness and painful ophthalmoplegia\u003c/b\u003e, a combination that should immediately prioritize CST in the differential diagnosis as it localizes pathology to both the intracranial space and the cavernous sinus.\u003c/p\u003e \u003cp\u003eSecond, identifying the \u003cb\u003einfectious source\u003c/b\u003e was obscure in the absence of typical portals like facial lesions or overt sinusitis. As previously noted, common infectious sources for CST encompass facial skin infections, sinusitis (particularly involving the sphenoid or ethmoid sinuses), dental procedures, otitis media or mastoiditis, and orbital cellulitis, among others[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The history of a subcutaneous injection near the temporal artery raised the possibility of an iatrogenic origin, highlighting that procedural history is crucial in seemingly cryptogenic cases.\u003c/p\u003e \u003cp\u003eThird, \u003cb\u003emicrobiological complexity\u003c/b\u003e added to the challenge. While initial CSF metagenomic sequencing suggested \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, subsequent cultures revealed a polymicrobial profile including MRSA, \u003cem\u003ePantoea agglomerans\u003c/em\u003e, MRSE, and \u003cem\u003eStreptococcus salivarius\u003c/em\u003e. This could represent true polymicrobial infection or sequential catheter colonization, a known confounding factor in CST diagnostics[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The confirmed presence of MRSA necessitated a dedicated antimicrobial strategy accounting for CNS penetration and resistance.\u003c/p\u003e \u003cp\u003eFinally, \u003cb\u003eearly neuroimaging\u003c/b\u003e was inconclusive. Definitive diagnosis was achieved through dedicated orbital MRI, which demonstrated bilateral superior ophthalmic vein (SOV) dilation and right cavernous sinus enlargement\u0026mdash;findings consistent with established radiological criteria that report high sensitivity and specificity for SOV dilation\u0026thinsp;\u0026ge;\u0026thinsp;2.9 mm in CST[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\n\u003ch3\u003e3. Therapeutic Decision-Making in a Complex Case\u003c/h3\u003e\n\u003cp\u003eManagement required navigating several interlinked therapeutic dilemmas.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eAntimicrobial Strategy and the Blood-Brain Barrier\u003c/strong\u003e \u003cp\u003eThe initial use of intravenous vancomycin, despite therapeutic serum trough levels, failed to sterilize the CSF and was followed by new cerebral infarcts, possibly from septic emboli. Switching to linezolid offered superior tissue penetration but was limited by myelosuppression. This sequence underscores the \u003cb\u003ecritical limitation of systemic antibiotics in achieving therapeutic CNS concentrations\u003c/b\u003e and argues for the early consideration of therapeutic drug monitoring (TDM). The eventual CSF sterilization was achieved only after the administration of \u003cb\u003eintraventricular vancomycin\u003c/b\u003e via an Ommaya reservoir, directly bypassing the blood-brain barrier. This supports the paradigm that direct intrathecal therapy should be a proactive consideration in culture-positive, refractory CNS infections, rather than a last resort[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eAnticoagulation Management\u003c/strong\u003e \u003cp\u003eTherapeutic anticoagulation with low-molecular-weight heparin was initiated for the septic thrombosis. The subsequent need for neurosurgical intervention due to hydrocephalus required a careful, ongoing risk-benefit assessment regarding bleeding. Our decision to continue anticoagulation is supported by meta-analytic data suggesting a significant mortality benefit with anticoagulation in CST (3.3% vs. 18%, p\u0026thinsp;=\u0026thinsp;0.022) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eSurgical Intervention and Source Control\u003c/strong\u003e \u003cp\u003eExternal ventricular drainage and Ommaya reservoir placement were initially performed to manage obstructive hydrocephalus. However, the persistence of positive CSF cultures despite optimal systemic antimicrobial therapy indicated either inadequate central nervous system drug penetration or a persistent localized infection. Otorhinolaryngological evaluation excluded surgical indications for sinusitis as a primary source. This scenario raised a critical differential diagnosis among true ongoing infection, specimen contamination, and catheter colonization. In this context, a study from the University Hospital Munich, Germany, is informative; it reported that while most biochemical markers from external ventricular drain (EVD) fluid show consistency between distal and proximal samples, cell counts and cytology remain reliant on proximal sampling[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. This suggests that biochemical parameters from drainage fluid retain diagnostic relevance. Given the suboptimal response to systemic therapy and the need to address a likely localized infectious nidus, the multidisciplinary team decided to escalate therapy. Consequently, intraventricular antibiotic administration was employed as a definitive, targeted strategy, aligning with the principle that in complicated CST, direct intervention\u0026mdash;whether surgical drainage of collections or, as in this case, direct antimicrobial delivery\u0026mdash;is crucial for source control[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eThe Imperative of Multidisciplinary Collaboration\u003c/strong\u003e \u003cp\u003eThis case exemplifies that optimal outcomes in complex CST are unattainable without seamless multidisciplinary team (MDT) integration. Coordinated input from neurology, neurosurgery, infectious diseases, ophthalmology, and otolaryngology was indispensable for diagnostic synthesis, timing of procedures, antimicrobial stewardship, and monitoring of complications. The literature strongly supports that such an MDT approach facilitates earlier diagnosis, personalized treatment, and improved outcomes, especially in atypical presentations[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e\n\u003ch3\u003e4. Clinical Implications\u003c/h3\u003e\n\u003cp\u003eThis case yields several practical insights. First, it reinforces that \u003cb\u003ediabetes and chronic alcohol use\u003c/b\u003e are significant risk modifiers that should lower the threshold for investigating CST. Second, it highlights \u003cb\u003eiatrogenic procedures\u003c/b\u003e as a potential, though often overlooked, portal of entry for devastating CNS infections, mandating strict aseptic technique. Third, it demonstrates that \u003cb\u003eintraventricular antibiotic therapy\u003c/b\u003e can be decisive in overcoming pharmacokinetic barriers in refractory cases. Finally, it validates a \u003cb\u003estructured MDT framework\u003c/b\u003e as the standard of care for managing CST with neurological complications.\u003c/p\u003e"},{"header":"Limitations","content":"\u003cp\u003eOur report has limitations inherent to a single case study. The precise origin of infection (iatrogenic vs. subclinical sinusitis) remains undetermined. While managed effectively, the potential for the indwelling Ommaya reservoir to contribute to biofilm-related persistence cannot be entirely excluded. Additionally, key follow-up laboratory data (including the CSF tNGS result from November 12, 2025) were obtained from an external institution, limiting our ability to independently verify the original data and detailed methodological parameters. Long-term neurological follow-up is required to assess for potential sequelae such as chronic cranial nerve deficits.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, this refractory case of MRSA CST with intracranial complications illustrates that successful outcomes depend on synthesizing subtle clinical clues, escalating decisively to direct CNS drug delivery when systemic therapy fails, and integrating multidisciplinary expertise from the outset. It serves as a salient reminder that in at-risk patients, CST must be considered promptly to mitigate its high morbidity, and that management often necessitates moving beyond conventional therapeutic paradigms to include innovative and targeted approaches.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCST \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Cavernous sinus thrombophlebitis\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMRSA \u0026nbsp; \u0026nbsp; \u0026nbsp;methicillin-resistant Staphylococcus aureus\u003c/p\u003e\n\u003cp\u003emNGS \u0026nbsp; \u0026nbsp; \u0026nbsp;Metagenomic next-generation sequencing\u003c/p\u003e\n\u003cp\u003eCSF \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;cerebrospinal fluid\u003c/p\u003e\n\u003cp\u003eMDROs \u0026nbsp; \u0026nbsp; multidrug-resistant organisms\u003c/p\u003e\n\u003cp\u003eWBC \u0026nbsp; \u0026nbsp; \u0026nbsp; white blood cell count\u003c/p\u003e\n\u003cp\u003eNE \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; neutrophil count\u003c/p\u003e\n\u003cp\u003eHB \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; hemoglobin\u003c/p\u003e\n\u003cp\u003ePLT \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;platelet count\u003c/p\u003e\n\u003cp\u003eCRP \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;C‑reactive protein\u003c/p\u003e\n\u003cp\u003eESR \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;erythrocyte sedimentation rate\u003c/p\u003e\n\u003cp\u003ePCT \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;procalcitonin\u003c/p\u003e\n\u003cp\u003eFER \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;ferritin\u003c/p\u003e\n\u003cp\u003eD‑D \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;D‑dimer\u003c/p\u003e\n\u003cp\u003eCNS \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;central nervous system\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTDM \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;therapeutic drug monitoring\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSOV \u0026nbsp; \u0026nbsp; \u0026nbsp; superior ophthalmic vein\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEVD \u0026nbsp; \u0026nbsp; \u0026nbsp; external ventricular drain\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMDT \u0026nbsp; \u0026nbsp; \u0026nbsp; multidisciplinary team\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis case report was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval for this study was obtained from the Peking University People's Hospital. Written informed consent was obtained from the patient for participation in this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication of this case report and any accompanying images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe raw metagenomic sequencing data generated during this study are available in the National Genomics Data Center (NGDC) Genome Sequence Archive (GSA) repository under BioProject accession number PRJCA055011 (https://ngdc.cncb.ac.cn/bioproject/browse/PRJCA055011). The data are currently under private access and will be made publicly available upon publication of this article. All other clinical data (including medical records and imaging studies) supporting the findings of this study are available within the article, or from the corresponding author on reasonable request, subject to privacy and ethical restrictions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYuanyuan Chen conceptualized the study, determined the report’s significance, collected and organized patient data (including imaging and laboratory results), performed the literature review, and drafted the initial manuscript. Jiacheng Liu and Song Wang were responsible for data curation and verified the accuracy of the data. Qingpei Hao contributed surgical data curation and provided clinical resources. Xia Liu performed imaging analysis and provided supervisory support. Yan Gao critically reviewed and edited the manuscript and provided overall supervision of the project. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to thank the patient for agreeing to the publication of this case. We thank Associate Researcher Yunyao Yin from the Department of Clinical Laboratory, Peking University People's Hospital, for providing the mNGS data and her expertise in microbiological analysis. We also thank the nursing staff of the Department of Neurosurgery for their dedicated patient care.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eCaranfa JT, Yoon MK. Septic cavernous sinus thrombosis: A review. Surv Ophthalmol. 2021;66(6):1021\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeerasinghe D, Lueck CJ. Septic Cavernous Sinus Thrombosis: Case Report and Review of the Literature. Neuroophthalmology. 2016;40(6):263\u0026ndash;76.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHousley SB, McPheeters MJ, Raygor KP, Bouslama M, Scullen T, Davies JM. Cavernous Sinus Thrombosis. Neurosurg Clin N Am. 2024;35(3):305\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAli S. Cavernous Sinus Thrombosis: Efficiently Recognizing and Treating a Life-Threatening Condition. Cureus. 2021;13(8):e17339.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSultania M, Das Majumdar SK, Raghuram K, Ganapathy A. A rare case of cavernous sinus thrombosis following oral squamous cell carcinoma - The etiology and management dilemma. Oral Oncol. 2023;142:106421.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarake\u0026ccedil;ili F, Barkay O, S\u0026uuml;mer B, Binay UD, Memiş KB, Yapıcıer \u0026Ouml;, Balcı MG. Invasive Aspergillosis with Cavernous Sinus Thrombosis Following High-Dose Corticosteroid Therapy: A Challenging Case of Rhino-Orbital-Cerebral Mycosis. J Fungi (Basel) 2024, 10(11).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKim J-M, Kang KW, Kim H, Lee S-H, Kim T-S, Park M-S. Septic cavernous sinus thrombosis after minor head trauma: A case report. Med (Baltim). 2022;101(10):e29057.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFujikawa T, Sogabe Y. Septic cavernous sinus thrombosis: potentially fatal conjunctival hyperemia. Intensive Care Med. 2018;45(5):692\u0026ndash;3.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGeng B, Wu X, Malhotra A. Septic cavernous sinus thrombosis-Case series and review of the literature. Clin Neurol Neurosurg. 2020;197:106092.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBhatia H, Kaur R, Bedi R. MR imaging of cavernous sinus thrombosis. Eur J Radiol Open. 2020;7:100226.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBodilsen J, D'Alessandris QG, Humphreys H, Iro MA, Klein M, Last K, Montesinos IL, Pagliano P, Sipahi OR, San-Juan R, et al. European society of Clinical Microbiology and Infectious Diseases guidelines on diagnosis and treatment of brain abscess in children and adults. Clin Microbiol Infect. 2023;30(1):66\u0026ndash;89.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkarapas C, Wiwatkunupakarn N, Sithirungson S, Chaiyasate S. Anticoagulation for cavernous sinus thrombosis: a systematic review and individual patient data meta-analysis. Eur Arch Otorhinolaryngol. 2024;282(3):1127\u0026ndash;34.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKinast CB, Paal M, Liebchen U. Comparison of Cerebrospinal Fluid Collection Through the Proximal and Distal Port Below the Overflow System from an External Ventricular Drain. Neurocrit Care. 2022;37(3):775\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003evan der Poel NA, Mourits MP, de Win MML, Coutinho JM, Dikkers FG. Prognosis of septic cavernous sinus thrombosis remarkably improved: a case series of 12 patients and literature review. Eur Arch Otorhinolaryngol. 2018;275(9):2387\u0026ndash;95.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-infectious-diseases","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"infd","sideBox":"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/infd","title":"BMC Infectious Diseases","twitterHandle":"#bmcinfectdis","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"cavernous sinus thrombophlebitis, brain abscess, hydrocephalus, methicillin-resistant Staphylococcus aureus (MRSA), multidisciplinary team, intraventricular antimicrobial therapy","lastPublishedDoi":"10.21203/rs.3.rs-8449809/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8449809/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Cavernous sinus thrombophlebitis (CST) is a rare, life-threatening infection with high morbidity. Its management becomes exceptionally challenging when complicated by intracranial abscesses, hydrocephalus, and multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase presentation:\u003c/strong\u003e We report a case of a 52-year-old woman with poorly controlled diabetes and chronic alcohol use, who presented with headache, fever, and ocular symptoms. Initial neuroimaging suggested sinusitis and ischemic lesions. Metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) detected Staphylococcus aureus. Despite comprehensive antimicrobial therapy (including meropenem, vancomycin, and linezolid), anti-inflammatory treatment, and anticoagulation, her clinical course deteriorated with the development of brain and lung abscesses, cerebral infarction, and obstructive hydrocephalus. Serial CSF cultures grew MRSA alongside other organisms (Pantoea agglomerans, MRSE, Streptococcus salivarius). Multidisciplinary management led to external ventricular drainage and, ultimately, intraventricular vancomycin administration via an Ommaya reservoir, which achieved CSF sterilization. A ventriculoperitoneal shunt was subsequently placed, with sustained clinical improvement.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e This case illustrates the severe and refractory nature of MRSA-associated CST with intracranial complications. It highlights the diagnostic challenges posed by atypical presentations and polymicrobial infections, and underscores the critical limitations of systemic antibiotics in penetrating the central nervous system. The successful outcome was contingent upon a proactive, multidisciplinary strategy that included timely surgical intervention and the strategic use of intraventricular antimicrobial therapy to overcome the blood-brain barrier. This report emphasizes the importance of dynamic monitoring, personalized treatment escalation, and integrated team-based care in managing such complex infections.\u003c/p\u003e","manuscriptTitle":"Refractory Cavernous Sinus Thrombophlebitis Complicated by Brain Abscess and Infectious Hydrocephalus: A Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-12 07:11:17","doi":"10.21203/rs.3.rs-8449809/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-04T07:38:58+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-17T19:47:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"331417407913073507432391324570082302106","date":"2026-01-16T04:15:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"75022328077310809121958630275916007698","date":"2026-01-11T01:51:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-10T19:06:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"71522670638701588973426710516613168176","date":"2026-01-10T18:21:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"13206432380160589169926122415599161326","date":"2026-01-10T15:14:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-10T15:06:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"219603114004953036629136208986955400008","date":"2026-01-10T14:49:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"318647581797518927274701401195299754486","date":"2026-01-09T12:53:39+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-08T02:45:34+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-05T05:44:26+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-03T14:04:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Infectious Diseases","date":"2026-01-03T13:58:30+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-infectious-diseases","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"infd","sideBox":"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/infd","title":"BMC Infectious Diseases","twitterHandle":"#bmcinfectdis","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"fe5251ba-c05f-4f19-83dc-7332de0f7857","owner":[],"postedDate":"January 12th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-04-27T16:19:17+00:00","versionOfRecord":{"articleIdentity":"rs-8449809","link":"https://doi.org/10.1186/s12879-026-13208-7","journal":{"identity":"bmc-infectious-diseases","isVorOnly":false,"title":"BMC Infectious Diseases"},"publishedOn":"2026-04-24 15:59:49","publishedOnDateReadable":"April 24th, 2026"},"versionCreatedAt":"2026-01-12 07:11:17","video":"","vorDoi":"10.1186/s12879-026-13208-7","vorDoiUrl":"https://doi.org/10.1186/s12879-026-13208-7","workflowStages":[]},"version":"v1","identity":"rs-8449809","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8449809","identity":"rs-8449809","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}