Dengue Encephalitis with Posterior Reversible Encephalopathy Syndrome-Like pattern: A Case Report from Singapore and Literature Review

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Neurological complications, such as dengue encephalitis and encephalopathy, are increasingly recognized; however, dengue-associated posterior reversible encephalopathy syndrome (PRES) remains rare. Case presentation We report a 90-year-old woman with primary dengue virus serotype 3 infection who developed persistent altered mental status during the early recovery phase of illness. Neuroimaging revealed bilateral asymmetric parieto-occipital vasogenic edema with focal hemorrhage, together with small acute infarcts in the deep watershed and left middle cerebral artery territories. Cerebrospinal fluid analysis demonstrated mildly elevated protein without pleocytosis; dengue IgM and IgG were positive, while dengue PCR was negative. She was managed as dengue encephalitis with PRES-like neuroradiological features and concomitant ischemic stroke. Follow-up imaging at two months showed near-complete radiological resolution. Conclusion This case highlights two important considerations. First, altered mental status in elderly patients with dengue should not be attributed solely to delirium, and prompt neurological evaluation is essential. Second, dengue infection may be associated with overlapping neurological manifestations, including dengue encephalitis, PRES-like vasogenic edema and cerebral infarct. Recognition of such overlap is important for accurate diagnosis and management of dengue-related central nervous system involvement. Case report Dengue Virus Infection Dengue encephalitis Posterior Reversible Encephalopathy Syndrome Neurological complications Figures Figure 1 BACKGROUND Dengue is hyperendemic in Singapore, with more than 13,000 cases reported in 2024. Dengue virus (DENV) infection typically presents with acute onset of fever, rashes, myalgia, arthralgia and lethargy, and severe disease may be complicated by hemorrhagic shock. Historically, dengue virus was considered to be non-neurotropic virus [ 1 ] , however, a recent review estimated that neurological manifestations occur in 0.5–21% of hospitalized dengue cases [ 2 ] , including dengue encephalopathy, dengue encephalitis, immune-mediated syndromes, neuromuscular dysfunctions and neuro-ophthalmic disorders [ 2 ] , particularly in DENV-2 and DENV-3 infections [ 1 ] . The neuropathogenesis of dengue remains poorly understood, and likely mechanisms include direct central nervous system (CNS) invasion, immune-mediated injury and metabolic alterations [ 1 , 3 ] . Neuroinflammation and cytokine activation may contribute to blood-brain disruption [ 1 ] . While dengue encephalitis is increasingly recognized, posterior reversible encephalopathy syndrome (PRES) has been rarely reported in association with dengue infection [ 1 ] . Although both conditions may present with altered mental status (AMS) or focal neurological deficits, they are considered distinct entities with different cerebrospinal fluid (CSF) and neuroimaging characteristics. Nevertheless, co-occurrence of those entities may occur in the setting of dengue related systemic inflammation and capillary leak, which may result in overlapping clinical and radiological features. Here, we report a 90-year-old woman with DENV-3 infection who developed dengue encephalitis with PRES-like neuroimaging changes, and concurrent ischemic stroke. To our knowledge, this is the oldest reported case of dengue-associated PRES-like neurological involvement. This case highlights that dengue encephalitis may co-exist with PRES or present with PRES-like imaging findings even in the absence of classical risk factors such as severe hypertension, autoimmune disease or immunosuppressive therapy. It also emphasizes the importance of considering dengue-related neurological complications in the elderly patients, in whom AMS is often misattributed to delirium. CASE PRESENTATION A 90-year-old Chinese woman with a history of hypertension, bilateral knee osteoarthritis, and erosive gastritis was admitted for five days of tactile fever, myalgia and reduced oral intake. She had previously been independent in daily activities but had developed mild amnestic cognitive impairment over the preceding months. On admission which was day 5 of illness, she was febrile and lethargic. Blood pressure was 163/71mmHg at supine and 145/65mmHg while seated. Physical examination was unremarkable and there were no dengue warning signs. Initial laboratory investigations showed a white blood cell count of 3.6 x 10 9 /L, hemoglobin of 11.9 g/dL, hematocrit of 36.6%, platelets count of 60 x 10 9 /L, and mildly elevated aspartate aminotransferase of 91 U/L. Dengue NS1 performed on day 4 of illness at a private clinic was positive, while IgM and IgG were negative, which suggested primary dengue virus infection. Her creatinine was elevated at 131 µmol/L, for which low-volume intravenous fluid was administered to mitigate acute kidney injury. On day 6 of illness, her hematocrit rose to 42.4% (a 15.8% increase), and platelet count further dropped to 21 x 10 9 /L, consistent with significant plasma leakage. On day 7, although platelet count and hematocrit had begun to improve, suggesting entering into the early dengue recovery phase, she developed persistent altered mental status. Ward staff noticed disorientation and abnormal behaviour, including smearing of stool. A delirium workup -including vitamin B12, folate, thyroid function, renal function and electrolytes, liver function, HIV and syphilis serology- was unremarkable. Non-contrast computed tomography (CT) of the brain on day 8 of illness showed bilateral parieto-occipital vasogenic edema. Subsequent magnetic resonance imaging (MRI) of the brain revealed confluent T2W/FLAIR (fluid-attenuated inversion recovery) hyperintensities with petechial hemorrhages in the bilateral parieto-occipital lobes (more prominent on the left), extending into the left temporal and frontal lobes. Mild leptomeningeal enhancement and additional parenchymal signal changes were also observed. Small acute infarcts were noted in the deep watershed and left middle cerebral artery (MCA) territories due to severe stenosis of the left internal carotid artery (Fig. 1a, b). Electroencephalogram (EEG) showed continuous diffuse slow activity with absence of normal background rhythm. CSF analysis revealed 19 red blood cells/µL, < 1 nucleated cell/µL and mildly elevated protein at 0.48 g/L. CSF Dengue IgM and IgG were positive while dengue PCR was negative. Serum dengue PCR confirmed DENV-3 serotype. Additional CSF studies including tetraplex PCR, FilmArray meningitis/encephalitis panel, cytology, and flow cytometry were negative. She was transferred to the neurology ward and managed as dengue encephalitis with a PRES-like imaging pattern and concurrent ischemic stroke. Aspirin and atorvastatin were initiated, and a nasogastric tube was inserted due to poor oral intake. After one month of hospitalization, she was discharged to a nursing facility. At 2-month follow-up, repeat MRI of the brain demonstrated near-complete resolution of prior white matter changes and leptomeningeal enhancement (Fig. 1c). At two years, she maintained independent, ambulant, but had significant cognitive impairment with a Mini-Mental State Examination (MMSE) score 9, consistent with Alzheimer's dementia. She was initiated on donepezil. DISCUSSION AND CONCLUSIONS Neurological complications following DENV infection are increasingly recognized and encompass a heterogenous spectrum of clinical and radiological manifestations, mediated by either direct virus neuro-invasion or immune-related injury. Dengue encephalopathy and encephalitis are the most commonly described entities [ 1 , 2 ] , while posterior reversible encephalopathy syndrome has emerged as a rare but increasingly reported neurological presentation in recent years. Importantly, these syndromes are not mutually exclusive, and may have overlapping clinical, radiological, and CSF features, which complicate the diagnosis and management. Our case described an elderly patient with DENV3 infection presenting with multiple neurological syndromes- dengue encephalitis, PRES-like neuroimaging changes, and concomitant ischemic stroke- illustrating the challenges of attributing neurological manifestation to a single pathological process within the spectrum of dengue-related central nervous system involvement. Dengue encephalopathy is generally attributed to systemic or metabolic disturbances- such as hepatic failure or renal failure, electrolytes imbalance, or shock –and is typically associated with normal CSF [ 2 ] . In contrast, dengue encephalitis is believed to result from direct viral invasion of the brain and commonly manifests with altered mental status, seizures or focal neurological deficits [ 4 ] . The diagnosis is confirmed by detection of DENV in the CSF, including NS1 antigen, dengue PCR or anti-DENV IgM [ 5 ] . However, CSF pleocytosis is inconsistently present, and normal CSF cellularity has been shown in more than half of dengue encephalitis cases [ 6 ] , highlighting the limitations of existing diagnostic definitions [ 2 ] . Posterior reversible encephalopathy syndrome is a clinical-radiological entity characterized by acute or subacute neurological symptoms- including encephalopathy, confusion, headache, visual disturbances and seizure- associated with neuroimaging findings of bilateral symmetrical vasogenic edema predominantly involving the parieto-occipital regions [ 7 , 8 , 9 ] . PRES is classically associated with severe hypertension, renal failure, eclampsia, autoimmune diseases, or exposure to cytotoxic or immunosuppressive agents, particularly calcineurin inhibitors. Infection triggers, including COVID and Lyme neuroborreliosis, have also been reported [ 7 ] . Beyond blood pressure dysregulation alone, endothelial dysfunction triggered by toxins or cytokines is increasingly recognized as a key contributor to PRES pathophysiology [ 7 ] . With appropriate management, neurological and radiological recovery are usually favourable. Dengue-associated PRES was first reported in a 27-year-old male with headache and blurred vision by Sohoni et al [ 10 ] . Since then, 11 more cases have been documented, primarily from dengue-endemic regions [ 11 – 21 ] . Our review of 12 reported cases (Table 1 ) demonstrates several consistent features. Most patients were young and predominantly females (83.3%), aged 8 to 68 years old, with 3 cases occurring during the late pregnancy. Classical PRES risk factors- such as chronic hypertension, autoimmune diseases, or cytotoxic/immunosuppressive exposure- were largely absent. Seizures were the most common neurological manifestation, occurring in 75% of patients, followed by altered mental status (50%), headache, and visual disturbances (33.3%). Blood pressure profiles were heterogenous, with hypotension and normotension observed as frequently as hypertension. CSF analysis, performed in approximately half of the cases, revealed mostly pleocytosis or elevated protein levels, with dengue IgM detected in 2 cases. Neuroimaging, predominantly MRI, typically demonstrated bilateral T2W/FLAIR hyperintensities involving the parieto-occipital regions with cortical and subcortical involvement. Compared with classical PRES cohorts, dengue-associated cases appear more likely to occur in patients without pre-existing vascular risk factors and in the setting of severe dengue, suggesting a potentially distinct precipitating context. Outcomes were general favourable with supportive treatment, although maternal and fetal mortality has been reported. Table 1 Characteristics of all reported cases of dengue PRES Author/ Year Age/sex Comorbidities Dengue diagnosis Features of severe dengue Blood pressure PRES symptoms CSF findings Brain imaging PRES management Outcome Sohoni et al. (2015) 10 27/M Nil Dengue NS1 and IgM positive Nil Normotensive Headache, blurring of vision Lymphocytic pleocytosis (85% lymphocytes), glucose 73 mg/dl, protein 102mg/dl Dengue IgM positive MRI: Symmetrical gyral hyperintensities in bilateral parieto-occipital regions on T2W/FLAIR Supportive treatment Recovered Nguyen et al.(2018) 11 55/F Nil Dengue NS1 positive Nil Normotensive Seizure AMS Slurred speech Cell count of 7 /ul, protein 4.4g/dl, Dengue IgM + ve, Dengue PCR -ve MRI: Bilateral symmetrical high signal on T2W/FLAIR over periventricular and deep cerebral white matter Steroids, AEDs Recovered Sawant et al. (2020) 12 10/F Nil Dengue NS1 positive Yes, respiratory distress and hypotension, DIC Hypertensive Seizure No red or white blood cell, protein 22.8 mg/dl, Dengue PCR -ve MRI: Symmetric cortical and subcortical hyperintensities over bilateral frontal, parietal, temporal and occipital parenchyma Antihypertensives; AEDs Recovered Biswas et al. (2024) 13 20/F 37weeks pregnant Dengue NS1 positive, IgM positive Yes, respiratory distress, hypotension, DIC Hypotensive AMS, vision loss, seizure Nil MRI: Cortico-subcortical T2W/FLAIR hyperintense areas in posterior parietal and occipital regions, cerebellum. AEDs Supportive treatment Death; Intrauterine death Sarkar et al. (2018) 14 68/F Nil Dengue NS1 positive, IgM positive Yes, hypotension Hypotensive AMS, seizure Cell count of 15/ul ( lymphocytic), protein 179 mg/dl MRI: T2W/FLAIR hyperintensities in bilateral parieto-occipital cortex with subcortical white matter AEDs Recovered Marakwad et al. (2022) 15 8/F Nil Dengue NS1 positive Nil Hypertensive Headache, seizure Nil MRI: Asymmetrical non enhancing areas of T2W/FLAIR hyperintensities in left parietal region AEDs Anti-hypertensives Recovered Manya et al. (2021) 16 15/F Nil Dengue NS1 positive Yes, hypotension Hypotensive Seizure Nil MRI: Multiple non-enhancing near symmetrical patchy areas of T2W/FLAIR hyperintensities over cerebral and cerebellum AEDs and supportive treatment Recovered Kour et al. (2023) 17 22/F 9months pregnant Dengue NS1 positive, IgM positive Nil Normotensive AMS, blurring of vision with hemianopia Nil CT: Bilateral occipital and parietal cortex white matter hypodensities AEDs and supportive treatment Recovered Kaur et al. (2022) 18 8/F Nil Nil Yes, hypotension Hypotensive Headache, seizure Nil MRI: T2W/FLAIR hyperintensities in subcortical regions of bilateral parieto-occipital lobes AEDs and supportive treatment Recovered Cheo et al. (2021) 19 15/M Nil Dengue NS1 positive; Dengue PCR: DENV2 Yes, compensated shock, respiratory distress Normotensive AMS Nil CT: Hypodensities at bilateral occipital regions and semiovale, predominantly white matter Supportive treatment Recovered Chaudhuri et al. (2023) 20 68/F Nil Dengue NS1 positive, IgM positive Yes, hypotension Hypotensive Seizure, AMS, blurring of vision Elevated protein, normal glucose and cell count MRI: Symmetrical hyperintensities in the parieto-occipital subcortical white matter Supportive treatment Recovered MAHMED. (2023) 21 28/F 32weeks pregnant Dengue NS1 positive Nil Normotensive Seizure, AMS White blood cell 3/mm3, protein 20mg/dl, glucose 40mg/dl MRI: Symmetrical parieto-occipital, fronto-parietal subcortical white matter hyperintensities AEDs, supportive treatment Recovered In our patient, differentiation between dengue encephalopathy, dengue encephalitis, PRES and ischemic stroke were particularly challenging due to overlapping clinical and radiological features. Altered mental status developed during the early dengue recovery phase and was initially attributed to delirium related to acute illness and environment factor. Subsequent neuroimaging and CSF evaluation revealed findings that could not be explained by a single diagnosis. The detection of anti DENV-IgM in the CSF supported dengue encephalitis, although the absence of CSF pleocytosis and negative CSF dengue PCR were atypical. These findings may reflect late-phase disease with reduced viral burden in the CSF or limitations in the assay sensitivity; and normal CSF cellularity has been well described in dengue encephalitis. Concurrently, MRI demonstrated bilateral parieto-occipital vasogenic edema consistent with PRES despite the absence of classical triggers such as severe hypertension, autoimmune disease, or exposure to immunosuppressant. Additional atypical features- including radiological asymmetry, intracranial hemorrhage, and concurrent watershed and middle cerebral artery territory infract- further suggested that multiple overlapping pathological processes contributed to patient’s neurological presentation. The pathophysiological mechanisms linking DENV infection to PRES-like manifestations remain poorly understood. Classical PRES is thought to arise from failure of cerebral autoregulation during acute blood pressure fluctuations or from toxin/cytokine-mediated endothelial dysfunction leading to blood-brain barrier disruption and vasogenic edema [ 7 , 8 ] . In dengue infection, severe plausible but unproven mechanisms could be proposed, including marked blood pressure fluctuations exceeding cerebral autoregulatory capacity, and exaggerated inflammatory cytokine responses increasing vascular permeability and endothelial dysfunction [ 6 , 11 ] . In addition, dengue viral factors such as non-structural protein 1 (NS1) have been shown to interact with endothelial surfaces and disrupt the endothelial glycocalyx, potentially exacerbating vascular leakage [ 1 , 16 ] . These observation are mainly derived from experimental studies [ 6 , 22 ] , and the exact mechanisms in human dengue-associated PRES remain uncertain. Dengue-associated PRES should therefore been interpreted within the recognized PRES spectrum, with dengue related inflammation, cytokine release and endothelial injury acting as potential precipitating factors. The strength of this case lies in its comprehensive clinical findings, CSF analysis, serial neuroimaging, and longitudinal follow-up, allowing a complete assessment of overlapping dengue-related neurological processes. As similar as most reported cases of dengue-associated PRES, the diagnosis relied on clinical-radiological-CSF features and disease evolution rather than pathological confirmation. This case adds to the limited literature on dengue-associated PRES and emphasizes the need to consider overlapping neurological processes in patient with dengue-related CNS presentations, particularly in elderly whose manifestations may be atypical. List of Abbreviations DENV, dengue virus CNS, central nervous system PRES, posterior reversible encephalopathy syndrome AMS, altered mental status CSF, cerebrospinal fluid CT, computed tomography MRI, magnetic resonance imaging MCA, middle cerebral artery EEG, electroencephalogram MMSE, Mini-Mental State Examination AEDs, Antiepileptic drugs DIC, Disseminated Intravascular Coagulation NS1, non-structural protein 1 T2W, T2-weight FLAIR, fluid-attenuated inversion recovery Declarations Ethical approval and consent to participate This case report was reviewed by the DSRB of NCID, Tan Tock Seng Hospital, NHG, which determined that formal ethical review and approval were not required for single-patient case reports. Consent to participant was therefore not applicable. Clinical Trial Clinical trial number: not applicable Consent for publication Written informed consent was obtained from the patient’s legally authorized representative for the publication of this case report and any accompanying images. Availability of data and material The data supporting the findings of this study are available within the article. Competing interests The authors declare that they have no competing interests. Funding The authors received no specific funding for this work. Authors’ contributions D.D.R: Conceptualization, manuscript writing, literature review W.K: Manuscript writing, literature review S.S.R/ M.Q.W.P : Clinical management of the patient and manuscript review Y.S.L: Manuscript editing, final approval of the manuscript Acknowledgements Not applicable. References Trivedi S, Chakravarty A. Neurological Complications of Dengue Fever. Curr Neurol Neurosci Rep. 2022;22(8):515–29. 10.1007/s11910-022-01213-7 . Carod-Artal FJ, Wichmann O, Farrar J, Gascón J. 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12:48:07","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":81015,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8433772/v1/90a29aa58892253077ffc11c.html"},{"id":100685469,"identity":"4896800f-54a8-4584-bb52-f697da484bbb","added_by":"auto","created_at":"2026-01-20 12:54:11","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":64005,"visible":true,"origin":"","legend":"\u003cp\u003ea) MRI brain with contrast: Confluent areas of T2 hyperintensities over deep and subcortical white matter bilaterally in the parieto-occipital lobes, more pronounced on the left, extending to the left temporal and left frontal lobes. There is possible cortical involvement.\u003c/p\u003e\n\u003cp\u003eb) Multiple scattered small foci of restricted diffusion over left deep white matter, including the left corona radiata, left parietal and left occipital lobes, consistent with acute infarcts in the deep watershed territory and left MCA territory.\u003c/p\u003e\n\u003cp\u003ec) MRI brain with contrast (2months after initial MRI): The confluent white matter T2 hyperintensities with mild mass effect previously seen in bilateral parieto-occipital, left temporal and left frontal lobes show interim resolution.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8433772/v1/dc7be1684d34ad1132b8011c.jpg"},{"id":103252216,"identity":"57cb41a0-9c98-4e89-8e28-dbfc267ce082","added_by":"auto","created_at":"2026-02-23 16:13:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":715916,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8433772/v1/483c21b5-905b-40db-9aa5-378ecd175738.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Dengue Encephalitis with Posterior Reversible Encephalopathy Syndrome-Like pattern: A Case Report from Singapore and Literature Review","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eDengue is hyperendemic in Singapore, with more than 13,000 cases reported in 2024. Dengue virus (DENV) infection typically presents with acute onset of fever, rashes, myalgia, arthralgia and lethargy, and severe disease may be complicated by hemorrhagic shock. Historically, dengue virus was considered to be non-neurotropic virus\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e, however, a recent review estimated that neurological manifestations occur in 0.5\u0026ndash;21% of hospitalized dengue cases\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e, including dengue encephalopathy, dengue encephalitis, immune-mediated syndromes, neuromuscular dysfunctions and neuro-ophthalmic disorders\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e, particularly in DENV-2 and DENV-3 infections\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe neuropathogenesis of dengue remains poorly understood, and likely mechanisms include direct central nervous system (CNS) invasion, immune-mediated injury and metabolic alterations\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Neuroinflammation and cytokine activation may contribute to blood-brain disruption\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. While dengue encephalitis is increasingly recognized, posterior reversible encephalopathy syndrome (PRES) has been rarely reported in association with dengue infection\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Although both conditions may present with altered mental status (AMS) or focal neurological deficits, they are considered distinct entities with different cerebrospinal fluid (CSF) and neuroimaging characteristics. Nevertheless, co-occurrence of those entities may occur in the setting of dengue related systemic inflammation and capillary leak, which may result in overlapping clinical and radiological features.\u003c/p\u003e \u003cp\u003eHere, we report a 90-year-old woman with DENV-3 infection who developed dengue encephalitis with PRES-like neuroimaging changes, and concurrent ischemic stroke. To our knowledge, this is the oldest reported case of dengue-associated PRES-like neurological involvement. This case highlights that dengue encephalitis may co-exist with PRES or present with PRES-like imaging findings even in the absence of classical risk factors such as severe hypertension, autoimmune disease or immunosuppressive therapy. It also emphasizes the importance of considering dengue-related neurological complications in the elderly patients, in whom AMS is often misattributed to delirium.\u003c/p\u003e"},{"header":"CASE PRESENTATION","content":"\u003cp\u003eA 90-year-old Chinese woman with a history of hypertension, bilateral knee osteoarthritis, and erosive gastritis was admitted for five days of tactile fever, myalgia and reduced oral intake. She had previously been independent in daily activities but had developed mild amnestic cognitive impairment over the preceding months.\u003c/p\u003e \u003cp\u003eOn admission which was day 5 of illness, she was febrile and lethargic. Blood pressure was 163/71mmHg at supine and 145/65mmHg while seated. Physical examination was unremarkable and there were no dengue warning signs. Initial laboratory investigations showed a white blood cell count of 3.6 x 10\u003csup\u003e9\u003c/sup\u003e/L, hemoglobin of 11.9 g/dL, hematocrit of 36.6%, platelets count of 60 x 10\u003csup\u003e9\u003c/sup\u003e/L, and mildly elevated aspartate aminotransferase of 91 U/L. Dengue NS1 performed on day 4 of illness at a private clinic was positive, while IgM and IgG were negative, which suggested primary dengue virus infection. Her creatinine was elevated at 131 µmol/L, for which low-volume intravenous fluid was administered to mitigate acute kidney injury.\u003c/p\u003e \u003cp\u003eOn day 6 of illness, her hematocrit rose to 42.4% (a 15.8% increase), and platelet count further dropped to 21 x 10\u003csup\u003e9\u003c/sup\u003e/L, consistent with\u003c/p\u003e \u003cp\u003esignificant plasma leakage.\u003c/p\u003e \u003cp\u003eOn day 7, although platelet count and hematocrit had begun to improve, suggesting entering into the early dengue recovery phase, she developed persistent altered mental status. Ward staff noticed disorientation and abnormal behaviour, including smearing of stool.\u003c/p\u003e \u003cp\u003eA delirium workup -including vitamin B12, folate, thyroid function, renal function and electrolytes, liver function, HIV and syphilis serology- was unremarkable. Non-contrast computed tomography (CT) of the brain on day 8 of illness showed bilateral parieto-occipital vasogenic edema. Subsequent magnetic resonance imaging (MRI) of the brain revealed confluent T2W/FLAIR (fluid-attenuated inversion recovery) hyperintensities with petechial hemorrhages in the bilateral parieto-occipital lobes (more prominent on the left), extending into the left temporal and frontal lobes. Mild leptomeningeal enhancement and additional parenchymal signal changes were also observed. Small acute infarcts were noted in the deep watershed and left middle cerebral artery (MCA) territories due to severe stenosis of the left internal carotid artery (Fig.\u0026nbsp;1a, b).\u003c/p\u003e \u003cp\u003eElectroencephalogram (EEG) showed continuous diffuse slow activity with absence of normal background rhythm. CSF analysis revealed 19 red blood cells/µL, \u0026lt; 1 nucleated cell/µL and mildly elevated protein at 0.48 g/L. CSF Dengue IgM and IgG were positive while dengue PCR was negative. Serum dengue PCR confirmed DENV-3 serotype. Additional CSF studies including tetraplex PCR, FilmArray meningitis/encephalitis panel, cytology, and flow cytometry were negative.\u003c/p\u003e \u003cp\u003eShe was transferred to the neurology ward and managed as dengue encephalitis with a PRES-like imaging pattern and concurrent ischemic stroke. Aspirin and atorvastatin were initiated, and a nasogastric tube was inserted due to poor oral intake. After one month of hospitalization, she was discharged to a nursing facility.\u003c/p\u003e \u003cp\u003eAt 2-month follow-up, repeat MRI of the brain demonstrated near-complete resolution of prior white matter changes and leptomeningeal enhancement (Fig.\u0026nbsp;1c). At two years, she maintained independent, ambulant, but had significant cognitive impairment with a Mini-Mental State Examination (MMSE) score 9, consistent with Alzheimer's dementia. She was initiated on donepezil.\u003c/p\u003e"},{"header":"DISCUSSION AND CONCLUSIONS","content":"\u003cp\u003eNeurological complications following DENV infection are increasingly recognized and encompass a heterogenous spectrum of clinical and radiological manifestations, mediated by either direct virus neuro-invasion or immune-related injury. Dengue encephalopathy and encephalitis are the most commonly described entities\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e, while posterior reversible encephalopathy syndrome has emerged as a rare but increasingly reported neurological presentation in recent years. Importantly, these syndromes are not mutually exclusive, and may have overlapping clinical, radiological, and CSF features, which complicate the diagnosis and management. Our case described an elderly patient with DENV3 infection presenting with multiple neurological syndromes- dengue encephalitis, PRES-like neuroimaging changes, and concomitant ischemic stroke- illustrating the challenges of attributing neurological manifestation to a single pathological process within the spectrum of dengue-related central nervous system involvement.\u003c/p\u003e\u003cp\u003eDengue encephalopathy is generally attributed to systemic or metabolic disturbances- such as hepatic failure or renal failure, electrolytes imbalance, or shock –and is typically associated with normal CSF\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e. In contrast, dengue encephalitis is believed to result from direct viral invasion of the brain and commonly manifests with altered mental status, seizures or focal neurological deficits\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. The diagnosis is confirmed by detection of DENV in the CSF, including NS1 antigen, dengue PCR or anti-DENV IgM\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. However, CSF pleocytosis is inconsistently present, and normal CSF cellularity has been shown in more than half of dengue encephalitis cases\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e, highlighting the limitations of existing diagnostic definitions\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e .\u003c/p\u003e\u003cp\u003ePosterior reversible encephalopathy syndrome is a clinical-radiological entity characterized by acute or subacute neurological symptoms- including encephalopathy, confusion, headache, visual disturbances and seizure- associated with neuroimaging findings of bilateral symmetrical vasogenic edema predominantly involving the parieto-occipital regions\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. PRES is classically associated with severe hypertension, renal failure, eclampsia, autoimmune diseases, or exposure to cytotoxic or immunosuppressive agents, particularly calcineurin inhibitors. Infection triggers, including COVID and Lyme neuroborreliosis, have also been reported\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. Beyond blood pressure dysregulation alone, endothelial dysfunction triggered by toxins or cytokines is increasingly recognized as a key contributor to PRES pathophysiology\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. With appropriate management, neurological and radiological recovery are usually favourable.\u003c/p\u003e\u003cp\u003eDengue-associated PRES was first reported in a 27-year-old male with headache and blurred vision by Sohoni et al\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. Since then, 11 more cases have been documented, primarily from dengue-endemic regions\u003csup\u003e[\u003cspan additionalcitationids=\"CR12 CR13 CR14 CR15 CR16 CR17 CR18 CR19 CR20\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e–\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e. Our review of 12 reported cases (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) demonstrates several consistent features. Most patients were young and predominantly females (83.3%), aged 8 to 68 years old, with 3 cases occurring during the late pregnancy. Classical PRES risk factors- such as chronic hypertension, autoimmune diseases, or cytotoxic/immunosuppressive exposure- were largely absent. Seizures were the most common neurological manifestation, occurring in 75% of patients, followed by altered mental status (50%), headache, and visual disturbances (33.3%). Blood pressure profiles were heterogenous, with hypotension and normotension observed as frequently as hypertension. CSF analysis, performed in approximately half of the cases, revealed mostly pleocytosis or elevated protein levels, with dengue IgM detected in 2 cases. Neuroimaging, predominantly MRI, typically demonstrated bilateral T2W/FLAIR hyperintensities involving the parieto-occipital regions with cortical and subcortical involvement. Compared with classical PRES cohorts, dengue-associated cases appear more likely to occur in patients without pre-existing vascular risk factors and in the setting of severe dengue, suggesting a potentially distinct precipitating context. Outcomes were general favourable with supportive treatment, although maternal and fetal mortality has been reported.\u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" 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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of all reported cases of dengue PRES\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"11\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAuthor/\u003c/p\u003e \u003cp\u003eYear\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAge/sex\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue diagnosis\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFeatures of severe dengue\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eBlood\u003c/p\u003e \u003cp\u003epressure\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePRES symptoms\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCSF findings\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eBrain imaging\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003ePRES management\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSohoni et al. (2015)\u003csup\u003e10\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27/M\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 and IgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNormotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eHeadache, blurring of vision\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eLymphocytic pleocytosis (85% lymphocytes), glucose 73 mg/dl, protein 102mg/dl\u003c/p\u003e \u003cp\u003eDengue IgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Symmetrical gyral hyperintensities in bilateral parieto-occipital regions on T2W/FLAIR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eSupportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNguyen et al.(2018)\u003csup\u003e11\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNormotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeizure\u003c/p\u003e \u003cp\u003eAMS\u003c/p\u003e \u003cp\u003eSlurred speech\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCell count of 7 /ul, protein 4.4g/dl,\u003c/p\u003e \u003cp\u003eDengue IgM + ve, Dengue PCR -ve\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Bilateral symmetrical high signal on T2W/FLAIR over periventricular and deep cerebral white matter\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eSteroids, AEDs\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSawant et al. (2020)\u003c/p\u003e \u003cp\u003e\u003csup\u003e12\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes,\u003c/p\u003e \u003cp\u003erespiratory distress and hypotension, DIC\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypertensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNo red or white blood cell, protein 22.8 mg/dl,\u003c/p\u003e \u003cp\u003eDengue PCR -ve\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Symmetric cortical and subcortical hyperintensities over bilateral frontal, parietal, temporal and occipital parenchyma\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAntihypertensives; AEDs\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiswas et al. (2024)\u003c/p\u003e \u003cp\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37weeks pregnant\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive,\u003c/p\u003e \u003cp\u003eIgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, respiratory distress, hypotension, DIC\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAMS, vision loss, seizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Cortico-subcortical T2W/FLAIR hyperintense areas in posterior parietal and occipital regions, cerebellum.\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs\u003c/p\u003e \u003cp\u003eSupportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eDeath;\u003c/p\u003e \u003cp\u003eIntrauterine death\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSarkar et al. (2018)\u003c/p\u003e \u003cp\u003e\u003csup\u003e14\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive, IgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, hypotension\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAMS, seizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCell count of 15/ul ( lymphocytic), protein 179 mg/dl\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: T2W/FLAIR hyperintensities in bilateral parieto-occipital cortex with subcortical white matter\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarakwad et al. (2022)\u003c/p\u003e \u003cp\u003e\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypertensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eHeadache, seizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Asymmetrical non enhancing areas of T2W/FLAIR hyperintensities in left parietal region\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs\u003c/p\u003e \u003cp\u003eAnti-hypertensives\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eManya et al. (2021)\u003c/p\u003e \u003cp\u003e\u003csup\u003e16\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, hypotension\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Multiple non-enhancing near symmetrical patchy areas of T2W/FLAIR hyperintensities over cerebral and cerebellum\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs and supportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKour et al. (2023)\u003c/p\u003e \u003cp\u003e\u003csup\u003e17\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9months pregnant\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive, IgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNormotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAMS, blurring of vision with hemianopia\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eCT: Bilateral occipital and parietal cortex white matter hypodensities\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs and supportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKaur et al. (2022)\u003c/p\u003e \u003cp\u003e\u003csup\u003e18\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, hypotension\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eHeadache, seizure\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: T2W/FLAIR hyperintensities in subcortical regions of bilateral parieto-occipital lobes\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs and supportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCheo et al. (2021)\u003c/p\u003e \u003cp\u003e\u003csup\u003e19\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15/M\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive;\u003c/p\u003e \u003cp\u003eDengue PCR: DENV2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, compensated shock, respiratory distress\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNormotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAMS\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eCT: Hypodensities at bilateral occipital regions and semiovale, predominantly white matter\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eSupportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChaudhuri et al. (2023)\u003c/p\u003e \u003cp\u003e\u003csup\u003e20\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive, IgM positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eYes, hypotension\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHypotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeizure, AMS, blurring of vision\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eElevated protein, normal glucose and cell count\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Symmetrical hyperintensities in the parieto-occipital subcortical white matter\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eSupportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMAHMED. (2023)\u003c/p\u003e \u003cp\u003e\u003csup\u003e21\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28/F\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32weeks pregnant\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDengue NS1 positive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNormotensive\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeizure, AMS\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eWhite blood cell 3/mm3, protein 20mg/dl, glucose 40mg/dl\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMRI: Symmetrical parieto-occipital, fronto-parietal subcortical white matter hyperintensities\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAEDs, supportive treatment\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRecovered\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e\u003cp\u003eIn our patient, differentiation between dengue encephalopathy, dengue encephalitis, PRES and ischemic stroke were particularly challenging due to overlapping clinical and radiological features. Altered mental status developed during the early dengue recovery phase and was initially attributed to delirium related to acute illness and environment factor. Subsequent neuroimaging and CSF evaluation revealed findings that could not be explained by a single diagnosis. The detection of anti DENV-IgM in the CSF supported dengue encephalitis, although the absence of CSF pleocytosis and negative CSF dengue PCR were atypical. These findings may reflect late-phase disease with reduced viral burden in the CSF or limitations in the assay sensitivity; and normal CSF cellularity has been well described in dengue encephalitis. Concurrently, MRI demonstrated bilateral parieto-occipital vasogenic edema consistent with PRES despite the absence of classical triggers such as severe hypertension, autoimmune disease, or exposure to immunosuppressant. Additional atypical features- including radiological asymmetry, intracranial hemorrhage, and concurrent watershed and middle cerebral artery territory infract- further suggested that multiple overlapping pathological processes contributed to patient’s neurological presentation.\u003c/p\u003e\u003cp\u003eThe pathophysiological mechanisms linking DENV infection to PRES-like manifestations remain poorly understood. Classical PRES is thought to arise from failure of cerebral autoregulation during acute blood pressure fluctuations or from toxin/cytokine-mediated endothelial dysfunction leading to blood-brain barrier disruption and vasogenic edema\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. In dengue infection, severe plausible but unproven mechanisms could be proposed, including marked blood pressure fluctuations exceeding cerebral autoregulatory capacity, and exaggerated inflammatory cytokine responses increasing vascular permeability and endothelial dysfunction\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. In addition, dengue viral factors such as non-structural protein 1 (NS1) have been shown to interact with endothelial surfaces and disrupt the endothelial glycocalyx, potentially exacerbating vascular leakage\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e. These observation are mainly derived from experimental studies\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e, and the exact mechanisms in human dengue-associated PRES remain uncertain. Dengue-associated PRES should therefore been interpreted within the recognized PRES spectrum, with dengue related inflammation, cytokine release and endothelial injury acting as potential precipitating factors.\u003c/p\u003e\u003cp\u003eThe strength of this case lies in its comprehensive clinical findings, CSF analysis, serial neuroimaging, and longitudinal follow-up, allowing a complete assessment of overlapping dengue-related neurological processes. As similar as most reported cases of dengue-associated PRES, the diagnosis relied on clinical-radiological-CSF features and disease evolution rather than pathological confirmation. This case adds to the limited literature on dengue-associated PRES and emphasizes the need to consider overlapping neurological processes in patient with dengue-related CNS presentations, particularly in elderly whose manifestations may be atypical.\u003c/p\u003e"},{"header":"List of Abbreviations","content":"\u003cp\u003eDENV, dengue virus\u003c/p\u003e\n\u003cp\u003eCNS, central nervous system\u003c/p\u003e\n\u003cp\u003ePRES, posterior reversible encephalopathy syndrome\u003c/p\u003e\n\u003cp\u003eAMS, altered mental status\u003c/p\u003e\n\u003cp\u003eCSF, cerebrospinal fluid\u003c/p\u003e\n\u003cp\u003eCT, computed tomography\u003c/p\u003e\n\u003cp\u003eMRI, magnetic resonance imaging\u003c/p\u003e\n\u003cp\u003eMCA, middle cerebral artery\u003c/p\u003e\n\u003cp\u003eEEG, electroencephalogram\u003c/p\u003e\n\u003cp\u003eMMSE, Mini-Mental State Examination\u003c/p\u003e\n\u003cp\u003eAEDs, Antiepileptic drugs\u003c/p\u003e\n\u003cp\u003eDIC, Disseminated Intravascular Coagulation\u003c/p\u003e\n\u003cp\u003eNS1, non-structural protein 1\u003c/p\u003e\n\u003cp\u003eT2W, T2-weight\u003c/p\u003e\n\u003cp\u003eFLAIR, fluid-attenuated inversion recovery\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis case report was reviewed by the DSRB of NCID, Tan Tock Seng Hospital, NHG, which determined that formal ethical review and approval were not required for single-patient case reports. Consent to participant was therefore not applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eClinical trial number: not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient’s legally authorized representative for the publication of this case report and any accompanying images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data supporting the findings of this study are available within the article.\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.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors received no specific funding for this work.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eD.D.R: Conceptualization, manuscript writing, literature review\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eW.K:\u0026nbsp;Manuscript writing, literature review\u003c/p\u003e\n\u003cp\u003eS.S.R/ M.Q.W.P\u003cstrong\u003e:\u003c/strong\u003e Clinical management of the patient and manuscript review\u003c/p\u003e\n\u003cp\u003eY.S.L: Manuscript editing, final approval of the manuscript\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eTrivedi S, Chakravarty A. 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Lancet Child Adolesc Health. 2019;3(10):734\u0026ndash;41. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/S2352-4642(19)30205-6\u003c/span\u003e\u003cspan address=\"10.1016/S2352-4642(19)30205-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\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":"Case report, Dengue Virus Infection, Dengue encephalitis, Posterior Reversible Encephalopathy Syndrome, Neurological complications","lastPublishedDoi":"10.21203/rs.3.rs-8433772/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8433772/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eDengue is hyperendemic in Singapore and typically presents as an acute febrile illness. Neurological complications, such as dengue encephalitis and encephalopathy, are increasingly recognized; however, dengue-associated posterior reversible encephalopathy syndrome (PRES) remains rare.\u003c/p\u003e\u003ch2\u003eCase presentation\u003c/h2\u003e \u003cp\u003eWe report a 90-year-old woman with primary dengue virus serotype 3 infection who developed persistent altered mental status during the early recovery phase of illness. Neuroimaging revealed bilateral asymmetric parieto-occipital vasogenic edema with focal hemorrhage, together with small acute infarcts in the deep watershed and left middle cerebral artery territories. Cerebrospinal fluid analysis demonstrated mildly elevated protein without pleocytosis; dengue IgM and IgG were positive, while dengue PCR was negative. She was managed as dengue encephalitis with PRES-like neuroradiological features and concomitant ischemic stroke. Follow-up imaging at two months showed near-complete radiological resolution.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis case highlights two important considerations. First, altered mental status in elderly patients with dengue should not be attributed solely to delirium, and prompt neurological evaluation is essential. Second, dengue infection may be associated with overlapping neurological manifestations, including dengue encephalitis, PRES-like vasogenic edema and cerebral infarct. Recognition of such overlap is important for accurate diagnosis and management of dengue-related central nervous system involvement.\u003c/p\u003e","manuscriptTitle":"Dengue Encephalitis with Posterior Reversible Encephalopathy Syndrome-Like pattern: A Case Report from Singapore and Literature Review","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-20 10:54:32","doi":"10.21203/rs.3.rs-8433772/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-04T07:34:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-03T14:00:15+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-03T13:59:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-28T16:19:41+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"198961195364981633766417592972104185563","date":"2026-01-22T08:56:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"228949708903742646047793703825019120368","date":"2026-01-22T06:26:38+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-21T07:45:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"129368498742655728395749754747299355632","date":"2026-01-21T07:00:17+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-20T12:21:56+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"121167684902358047474411588220621851292","date":"2026-01-18T22:30:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"7186804238913513942068297508835206226","date":"2026-01-16T17:37:22+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-15T15:24:05+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-29T13:06:42+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-26T05:19:25+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-26T05:19:09+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Infectious Diseases","date":"2025-12-23T12:30:42+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":"dc19b99f-9360-488e-bbd4-d5791064d0fc","owner":[],"postedDate":"January 20th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-02-23T16:10:26+00:00","versionOfRecord":{"articleIdentity":"rs-8433772","link":"https://doi.org/10.1186/s12879-026-12920-8","journal":{"identity":"bmc-infectious-diseases","isVorOnly":false,"title":"BMC Infectious Diseases"},"publishedOn":"2026-02-21 15:59:49","publishedOnDateReadable":"February 21st, 2026"},"versionCreatedAt":"2026-01-20 10:54:32","video":"","vorDoi":"10.1186/s12879-026-12920-8","vorDoiUrl":"https://doi.org/10.1186/s12879-026-12920-8","workflowStages":[]},"version":"v1","identity":"rs-8433772","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8433772","identity":"rs-8433772","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}