A Rare Occurrence of Lepra Type II Reaction in Pure Neuritic Leprosy: A Case Report

A Rare Occurrence of Lepra Type II Reaction in Pure Neuritic Leprosy: A Case Report | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report A Rare Occurrence of Lepra Type II Reaction in Pure Neuritic Leprosy: A Case Report Nardos Asfaw, Adane Mekonnen Gebrewold This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7895735/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 20 Jan, 2026 Read the published version in BMC Infectious Diseases → Version 1 posted 11 You are reading this latest preprint version Abstract Background: Pure neuritic leprosy (PNL) is an uncommon clinical form of leprosy characterized by nerve involvement without skin lesions, making diagnosis challenging. Type II lepra reaction (erythema nodosum leprosum, ENL) is rarely associated with PNL. Case Presentation: We report a 39-year-old male from Harar, Ethiopia, who presented with a 10-month history of progressive numbness, tingling, and weakness in the left hand. Clinical examination revealed thickened and tender ulnar nerve, sensory loss, hypothenar atrophy, and clawing of the ring and little fingers. Nerve conduction studies confirmed severe ulnar neuropathy, and ear-lobe biopsy demonstrated paucibacillary leprosy, establishing the diagnosis of PNL with Grade II disability. The patient was started on standard WHO multidrug therapy (MDT). After three weeks, he developed fever, arthritis, and tender supraorbital nodules consistent with Type II lepra reaction. He was managed with corticosteroids, physiotherapy, and continuation of MDT. Systemic symptoms subsided, though neurological deficits persisted. Conclusion: This case highlights the diagnostic challenges of PNL in the absence of skin lesions and the rare occurrence of Type II lepra reaction in this form. Early recognition, integration of advanced diagnostic tools, and timely physiotherapy are crucial to minimize disability in endemic settings. Type II reaction Pure neuritic leprosy Erythema nodosum leprosum Ethiopia Figures Figure 1 Figure 2 1. Introduction Pure neuritic leprosy (PNL) roughly accounts for 4–10% of all leprosy cases globally. It is a distinct clinical form of leprosy where nerve involvement occurs without the typical skin lesions or the presence of the leprosy bacillus in skin smears, making its diagnosis challenging. ( 1 )The global prevalence of leprosy is declining, though high numbers of new cases annually reported from countries like the democratic republic of Congo and Ethiopia. Ethiopia is the second most affected country in Sub-Saharan Africa (SSA), after the Democratic Republic of Congo. Annually, 4000–4500 new cases were diagnosed at health facilities between 2004 and 2010. ( 2 ) Pure neuritic Leprosy is less commonly reported in some parts of the world such as Africa. ( 3 ) A Type II reaction, also known as Erythema Nodosum Leprosum (ENL) is an immune-mediated inflammatory complication that can occur during or after treatment of leprosy that presents with systemic symptoms like Fever, malaise, arthritis and Painful nodules. This phenomenon is more commonly seen in Virulent lepromatous(LL) and Borderline Lepromatous (BL) cases and it is less common in Pure neuritc presentation which are a small subset of the total case. A type II reaction in patients with Pure neuritic leprosy (PNL) is extremely rare making diagnosis challenging. Although Ethiopia has a substantial number of Leprosy cases, PNL remain s a challenging form to detect. Recognizing and managing such cases require high index of suspicion and a multidisciplinary approach to prevent long- term disability. We present a rare case of PNL complicated by Type II Lepra reaction in an Ethiopian patient. Emphasizing the diagnostic and therapeutic challenges associated with this unusual presentation 2. Case Report Case Presentation A 39-year-old male ex-sergeant from Harar, Ethiopia, presented with a 10-month history of numbness and tingling along the ulnar aspect of the left upper limb, accompanied by progressive weakness of grip strength. There was no history of trauma, systemic illness, drug exposure, or family history of neurological disorders. No skin lesions were evident at presentation. Clinical examination revealed a thickened and tender left ulnar nerve with complete sensory loss to temperature and touch in its distribution. The left hand showed hypothenar atrophy and clawing of the ring and little fingers. No hypopigmented or erythematous skin lesions suggestive of leprosy were identified. Diagnostic Work-Up Nerve conduction study (NCS): Severe asymmetric axonal sensory-motor neuropathy of the left ulnar nerve. Slit-skin smear: Negative. Ear-lobe biopsy: Demonstrated paucibacillary leprosy. Blood tests (CBC, ESR, CRP): Non-specific inflammatory findings. Ultrasound of ulnar nerve: Marked thickening with altered fascicular pattern consistent with leprosy neuropathy. A final diagnosis of pure neuritic leprosy (PNL) with Grade II disability was made. Treatment and Clinical Course The patient was initiated on standard WHO MDT for multibacillary leprosy: Dapsone 100 mg daily; Clofazimine 50 mg daily and 300 mg monthly; Rifampicin 600 mg monthly. After three weeks, the patient developed fever, malaise, arthritis, and tender supraorbital nodules consistent with Type II lepra reaction (ENL). Management of Lepra Reaction He was treated with prednisolone 40 mg daily (tapered), amitriptyline 25 mg nightly for neuropathic pain, and physiotherapy. MDT was continued. Response to Treatment Systemic symptoms subsided following corticosteroid therapy. Physiotherapy improved joint mobility and prevented deformities, but sensory loss and clawing persisted. During steroid tapering, the patient experienced recurrence of ENL symptoms with supraorbital nodules and arthritis. 3. Discussion Pure neuritic leprosy is a distinct clinical form of leprosy where nerve involvement occurs without the typical skin lesions and is an uncommon and diagnostically challenging form of Hansen’s It is known that PNL is uncommon and has been reported only in 1.5% to 8.1% of leprosy patients. However, recent Indian studies have shown a greater incidence of PNL amongst the leprosy cases diagnosed ranging from 5.5% to 18% disease. ( 4 ) It is defined by nerve involvement in the absence of clinically evident skin lesion. The absence of cutaneous manifestation makes diagnosis challenging. Clinical suspicion, careful neurological examination, and nerve palpation are therefore essential in endemic regions. The occurrence of a Type II Lepra reaction (Erythema nodosum Leprosum) is rare and unexpected form of reaction but clinically significant specifically in Pure neuritic leprosy. In a histopathological study of skin and nerve biopsies in 17pure neuritic leprosy patients at Karigiri, India, seven (41.2%) were classified in the lepromaous group and 10(58.8%) in non-lepromatous group,( 5 ) our case reported here is grouped under non lepromatous group based on the ear lobe biopsy which showed paucibacillary result our patient later developed Type II Reaction (ENL) while on treatment which is more typically associated with multibacillary disease. There are only limited number of case reports documented on Type II lepra reaction in the context of PNL. A case reported from India in 2020, on a 30year old male with PNL with nerve involvement and negative slit skin smears showed lepromatous neuritis which later during MDT the patient developed ENL (Type II reaction) which was treated successfully with steroids and thalidomide.( 6 ) Our case aligns with the earlier report, demonstrating that ENL can occur even in the absence of overt cutaneous involvement. The patient's clinical history and absence of skin lesions fulfilled the criteria for PNL; however, the onset of ENL—with classical features such as painful nodules, fever, and systemic symptoms—prompted further diagnostic workup. In contrast to our case, there was a report of an adult female diagnosed with pure neuritic leprosy, who later developed Type I reaction in the form of neuritis, pedal edema and appearance of erythematous and edematous new skin lesion over the cheek and type I reaction was confirmed by histopathology.( 7 ) In comparison to previously reported case, this report contributes further evidence that ENL can be an evolving feature of PNL challenging conventional classifications. This support that leprosy exists on a dynamic immunopathological spectrum and that clinicians must remain vigilant for systemic manifestations most importantly during treatment. The case is more unusual compared to the limited PNL and type II reaction reports since the patient developed recurrence of symptoms of reaction while on steroid tapering.. 4. Conclusion This case demonstrates the difficulties in diagnosing and treating pure neuritic leprosy, especially when a type II lepra response complicates the case. In endemic areas, the lack of cutaneous manifestations frequently causes delays in diagnosis, highlighting the significance of strong clinical suspicion and comprehensive neurological assessment. Type II reactions must be promptly identified and appropriately managed to avoid irreversible nerve damage and impairment. This paper highlights the necessity of early intervention, multidisciplinary care and long term follow up in order to guarantee the best possible results for patients with such presentation 5. Recommendations Early referral for specialized diagnostic evaluation in suspected PNL cases. Incorporation of high-resolution ultrasound (HRUS), PCR, and serological testing in diagnostic algorithms. Regular monitoring for lepra reactions during MDT, even in atypical forms. Early initiation of physiotherapy and occupational therapy to prevent disability. Development of community-based rehabilitation programs for social and functional reintegration. 6. Limitation:- This case report has several constraints that should be recognized, the first one is the lack of diagnostic resources prevented us from conducting early confirmatory tests therefore the diagnosis relied primarily on clinical basis. This report focuses on a single case, the findings cannot be extrapolated to all patients with pure neuritic leprosy. Declarations Informed Consent Written informed consent was obtained from the patient for publication of this case report. Ethical Consideration The case report was prepared in accordance with international ethical guidelines for clinical case reporting. Authorship All authors contributed to patient management, data collection, and manuscript preparation. All have approved the final version. Author Contribution All authors contributed to patient management, data collection, and manuscript preparation. All have approved the final version. Acknowledgement We would like to thank the patient for his cooperation and consent to share his case for academic purposes. We also acknowledge the healthcare staff involved in his diagnosis and management. References Sharma VK, Malhotra AK. Leprosy: Classification and clinical aspects. In: Valia RG, Valia AR, editors. IADVL Text Book of Dermatology. 3rd ed. Mumbai: Bhalani Publishing House; 2008. pp. 2032–69. Global leprosysituation. 2010. Wkly Epidemiol Rec. 2010;85(35):337–48. Rao PN, Suneetha S. Pure neuritic leprosy: Current status and relevance. Indian J Dermatol Venereol Leprol. 2016;82:252–61. Kale K, Gadgil NM, Chaudhari C. Pure Neuritic Leprosy : A Series of Three Cases. Indian J Lepr. 2020;92:125–30. Pannikar VK, Arunthathi S, Chacko CJ, Fritschi EP. A clinico-pathological study of primary neuritic leprosy. Lepr India. 1983;55:212–21. Fernandes E, Pai VV, Shukla P, et al. Pure neuritic leprosy with Type 2 reaction. Indian J Lepr. 2020;92:57–61. Pathak R, Agrawal S, Paudyal P. Rare occurrence of lepra type 1 reaction in pure neuritic leprosy: A case report. Clin Case Rep. 2021;9:e04324. https://doi.org/10.1002/ccr3.4324 . Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 20 Jan, 2026 Read the published version in BMC Infectious Diseases → Version 1 posted Editorial decision: Revision requested 19 Nov, 2025 Reviewers agreed at journal 18 Nov, 2025 Reviews received at journal 18 Nov, 2025 Reviewers agreed at journal 17 Nov, 2025 Reviews received at journal 12 Nov, 2025 Reviewers agreed at journal 05 Nov, 2025 Reviewers agreed at journal 05 Nov, 2025 Reviewers invited by journal 05 Nov, 2025 Editor assigned by journal 31 Oct, 2025 Submission checks completed at journal 30 Oct, 2025 First submitted to journal 30 Oct, 2025 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Introduction","content":"\u003cp\u003ePure neuritic leprosy (PNL) roughly accounts for 4\u0026ndash;10% of all leprosy cases globally. It is a distinct clinical form of leprosy where nerve involvement occurs without the typical skin lesions or the presence of the leprosy bacillus in skin smears, making its diagnosis challenging. (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)The global prevalence of leprosy is declining, though high numbers of new cases annually reported from countries like the democratic republic of Congo and Ethiopia. Ethiopia is the second most affected country in Sub-Saharan Africa (SSA), after the Democratic Republic of Congo. Annually, 4000\u0026ndash;4500 new cases were diagnosed at health facilities between 2004 and 2010. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) Pure neuritic Leprosy is less commonly reported in some parts of the world such as Africa. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eA Type II reaction, also known as Erythema Nodosum Leprosum (ENL) is an immune-mediated inflammatory complication that can occur during or after treatment of leprosy that presents with systemic symptoms like Fever, malaise, arthritis and Painful nodules. This phenomenon is more commonly seen in Virulent lepromatous(LL) and Borderline Lepromatous (BL) cases and it is less common in Pure neuritc presentation which are a small subset of the total case.\u003c/p\u003e\u003cp\u003eA type II reaction in patients with Pure neuritic leprosy (PNL) is extremely rare making diagnosis challenging. Although Ethiopia has a substantial number of Leprosy cases, PNL remain s a challenging form to detect. Recognizing and managing such cases require high index of suspicion and a multidisciplinary approach to prevent long- term disability.\u003c/p\u003e\u003cp\u003eWe present a rare case of PNL complicated by Type II Lepra reaction in an Ethiopian patient. Emphasizing the diagnostic and therapeutic challenges associated with this unusual presentation\u003c/p\u003e"},{"header":"2. Case Report","content":"\u003cp\u003e\u003cstrong\u003eCase Presentation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA 39-year-old male ex-sergeant from Harar, Ethiopia, presented with a 10-month history of numbness and tingling along the ulnar aspect of the left upper limb, accompanied by progressive weakness of grip strength. There was no history of trauma, systemic illness, drug exposure, or family history of neurological disorders. No skin lesions were evident at presentation.\u003c/p\u003e\n\u003cp\u003eClinical examination revealed a thickened and tender left ulnar nerve with complete sensory loss to temperature and touch in its distribution. The left hand showed hypothenar atrophy and clawing of the ring and little fingers. No hypopigmented or erythematous skin lesions suggestive of leprosy were identified.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiagnostic Work-Up\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eNerve conduction study (NCS): Severe asymmetric axonal sensory-motor neuropathy of the left ulnar nerve.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eSlit-skin smear: Negative.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eEar-lobe biopsy: Demonstrated paucibacillary leprosy.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eBlood tests (CBC, ESR, CRP): Non-specific inflammatory findings.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eUltrasound of ulnar nerve: Marked thickening with altered fascicular pattern consistent with leprosy neuropathy.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eA final diagnosis of pure neuritic leprosy (PNL) with Grade II disability was made.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTreatment and Clinical Course\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe patient was initiated on standard WHO MDT for multibacillary leprosy:\u003c/p\u003e\n\u003cp\u003eDapsone 100 mg daily; Clofazimine 50 mg daily and 300 mg monthly; Rifampicin 600 mg monthly.\u003c/p\u003e\n\u003cp\u003eAfter three weeks, the patient developed fever, malaise, arthritis, and tender supraorbital nodules consistent with Type II lepra reaction (ENL).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eManagement of Lepra Reaction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHe was treated with prednisolone 40 mg daily (tapered), amitriptyline 25 mg nightly for neuropathic pain, and physiotherapy. MDT was continued.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResponse to Treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSystemic symptoms subsided following corticosteroid therapy. Physiotherapy improved joint mobility and prevented deformities, but sensory loss and clawing persisted. During steroid tapering, the patient experienced recurrence of ENL symptoms with supraorbital nodules and arthritis.\u003c/p\u003e"},{"header":"3. Discussion","content":"\u003cp\u003ePure neuritic leprosy is a distinct clinical form of leprosy where nerve involvement occurs without the typical skin lesions and is an uncommon and diagnostically challenging form of Hansen\u0026rsquo;s It is known that PNL is uncommon and has been reported only in 1.5% to 8.1% of leprosy patients. However, recent Indian studies have shown a greater incidence of PNL amongst the leprosy cases diagnosed ranging from 5.5% to 18% disease. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) It is defined by nerve involvement in the absence of clinically evident skin lesion.\u003c/p\u003e\u003cp\u003eThe absence of cutaneous manifestation makes diagnosis challenging. Clinical suspicion, careful neurological examination, and nerve palpation are therefore essential in endemic regions.\u003c/p\u003e\u003cp\u003eThe occurrence of a Type II Lepra reaction (Erythema nodosum Leprosum) is rare and unexpected form of reaction but clinically significant specifically in Pure neuritic leprosy.\u003c/p\u003e\u003cp\u003eIn a histopathological study of skin and nerve biopsies in 17pure neuritic leprosy patients at Karigiri, India, seven (41.2%) were classified in the lepromaous group and 10(58.8%) in non-lepromatous group,(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) our case reported here is grouped under non lepromatous group based on the ear lobe biopsy which showed paucibacillary result our patient later developed Type II Reaction (ENL) while on treatment which is more typically associated with multibacillary disease.\u003c/p\u003e\u003cp\u003eThere are only limited number of case reports documented on Type II lepra reaction in the context of PNL.\u003c/p\u003e\u003cp\u003eA case reported from India in 2020, on a 30year old male with PNL with nerve involvement and negative slit skin smears showed lepromatous neuritis which later during MDT the patient developed ENL (Type II reaction) which was treated successfully with steroids and thalidomide.(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eOur case aligns with the earlier report, demonstrating that ENL can occur even in the absence of overt cutaneous involvement. The patient's clinical history and absence of skin lesions fulfilled the criteria for PNL; however, the onset of ENL\u0026mdash;with classical features such as painful nodules, fever, and systemic symptoms\u0026mdash;prompted further diagnostic workup.\u003c/p\u003e\u003cp\u003eIn contrast to our case, there was a report of an adult female diagnosed with pure neuritic leprosy, who later developed Type I reaction in the form of neuritis, pedal edema and appearance of erythematous and edematous new skin lesion over the cheek and type I reaction was confirmed by histopathology.(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eIn comparison to previously reported case, this report contributes further evidence that ENL can be an evolving feature of PNL challenging conventional classifications. This support that leprosy exists on a dynamic immunopathological spectrum and that clinicians must remain vigilant for systemic manifestations most importantly during treatment.\u003c/p\u003e\u003cp\u003eThe case is more unusual compared to the limited PNL and type II reaction reports since the patient developed recurrence of symptoms of reaction while on steroid tapering..\u003c/p\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThis case demonstrates the difficulties in diagnosing and treating pure neuritic leprosy, especially when a type II lepra response complicates the case. In endemic areas, the lack of cutaneous manifestations frequently causes delays in diagnosis, highlighting the significance of strong clinical suspicion and comprehensive neurological assessment. Type II reactions must be promptly identified and appropriately managed to avoid irreversible nerve damage and impairment. This paper highlights the necessity of early intervention, multidisciplinary care and long term follow up in order to guarantee the best possible results for patients with such presentation\u003c/p\u003e\n\u003ch3\u003e5. Recommendations\u003c/h3\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eEarly referral for specialized diagnostic evaluation in suspected PNL cases.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eIncorporation of high-resolution ultrasound (HRUS), PCR, and serological testing in diagnostic algorithms.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eRegular monitoring for lepra reactions during MDT, even in atypical forms.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eEarly initiation of physiotherapy and occupational therapy to prevent disability.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eDevelopment of community-based rehabilitation programs for social and functional reintegration.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cspan\u003e\u003cstrong\u003e6. Limitation:-\u003c/strong\u003e This case report has several constraints that should be recognized, the first one is the lack of diagnostic resources prevented us from conducting early confirmatory tests therefore the diagnosis relied primarily on clinical basis. This report focuses on a single case, the findings cannot be extrapolated to all patients with pure neuritic leprosy.\u003cbr\u003e\u003c/span\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eInformed Consent\u003c/h2\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication of this case report.\u003c/p\u003e\n\u003ch2\u003eEthical Consideration\u003c/h2\u003e\n\u003cp\u003eThe case report was prepared in accordance with international ethical guidelines for clinical case reporting.\u003c/p\u003e\n\u003ch2\u003eAuthorship\u003c/h2\u003e\n\u003cp\u003eAll authors contributed to patient management, data collection, and manuscript preparation. All have approved the final version.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eAll authors contributed to patient management, data collection, and manuscript preparation. All have approved the final version.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eWe would like to thank the patient for his cooperation and consent to share his case for academic purposes. We also acknowledge the healthcare staff involved in his diagnosis and management.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSharma VK, Malhotra AK. Leprosy: Classification and clinical aspects. In: Valia RG, Valia AR, editors. IADVL Text Book of Dermatology. 3rd ed. Mumbai: Bhalani Publishing House; 2008. pp. 2032\u0026ndash;69.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGlobal leprosysituation. 2010. Wkly Epidemiol Rec. 2010;85(35):337\u0026ndash;48.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRao PN, Suneetha S. Pure neuritic leprosy: Current status and relevance. Indian J Dermatol Venereol Leprol. 2016;82:252\u0026ndash;61.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKale K, Gadgil NM, Chaudhari C. Pure Neuritic Leprosy : A Series of Three Cases. Indian J Lepr. 2020;92:125\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePannikar VK, Arunthathi S, Chacko CJ, Fritschi EP. A clinico-pathological study of primary neuritic leprosy. Lepr India. 1983;55:212\u0026ndash;21.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFernandes E, Pai VV, Shukla P, et al. Pure neuritic leprosy with Type 2 reaction. Indian J Lepr. 2020;92:57\u0026ndash;61.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePathak R, Agrawal S, Paudyal P. Rare occurrence of lepra type 1 reaction in pure neuritic leprosy: A case report. Clin Case Rep. 2021;9:e04324. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/ccr3.4324\u003c/span\u003e\u003cspan address=\"10.1002/ccr3.4324\" 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":"Type II reaction, Pure neuritic leprosy, Erythema nodosum leprosum, Ethiopia","lastPublishedDoi":"10.21203/rs.3.rs-7895735/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7895735/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground: Pure neuritic leprosy (PNL) is an uncommon clinical form of leprosy characterized by nerve involvement without skin lesions, making diagnosis challenging. Type II lepra reaction (erythema nodosum leprosum, ENL) is rarely associated with PNL.\u003c/p\u003e\n\u003cp\u003eCase Presentation: We report a 39-year-old male from Harar, Ethiopia, who presented with a 10-month history of progressive numbness, tingling, and weakness in the left hand. Clinical examination revealed thickened and tender ulnar nerve, sensory loss, hypothenar atrophy, and clawing of the ring and little fingers. Nerve conduction studies confirmed severe ulnar neuropathy, and ear-lobe biopsy demonstrated paucibacillary leprosy, establishing the diagnosis of PNL with Grade II disability. The patient was started on standard WHO multidrug therapy (MDT). After three weeks, he developed fever, arthritis, and tender supraorbital nodules consistent with Type II lepra reaction. He was managed with corticosteroids, physiotherapy, and continuation of MDT. Systemic symptoms subsided, though neurological deficits persisted.\u003cbr\u003e\n\u003c/p\u003e\n\u003cp\u003eConclusion: This case highlights the diagnostic challenges of PNL in the absence of skin lesions and the rare occurrence of Type II lepra reaction in this form. Early recognition, integration of advanced diagnostic tools, and timely physiotherapy are crucial to minimize disability in endemic settings.\u003c/p\u003e","manuscriptTitle":"A Rare Occurrence of Lepra Type II Reaction in Pure Neuritic Leprosy: A Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-17 06:32:15","doi":"10.21203/rs.3.rs-7895735/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-11-19T08:30:23+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"293946258106564636058374412244655648504","date":"2025-11-18T21:57:24+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-18T05:04:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"94497254270975153143542792926188945433","date":"2025-11-18T04:59:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-12T08:20:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"66353503132524889744797011202757521886","date":"2025-11-05T07:31:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"179710272516808028514060434211880893989","date":"2025-11-05T07:18:51+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-05T07:11:07+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-31T07:01:12+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-30T18:51:18+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Infectious Diseases","date":"2025-10-30T18:48:54+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":"f85c8c2a-d814-4900-9f43-f4328dfbc0b2","owner":[],"postedDate":"November 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-01-26T16:06:58+00:00","versionOfRecord":{"articleIdentity":"rs-7895735","link":"https://doi.org/10.1186/s12879-026-12636-9","journal":{"identity":"bmc-infectious-diseases","isVorOnly":false,"title":"BMC Infectious Diseases"},"publishedOn":"2026-01-20 15:57:13","publishedOnDateReadable":"January 20th, 2026"},"versionCreatedAt":"2025-11-17 06:32:15","video":"","vorDoi":"10.1186/s12879-026-12636-9","vorDoiUrl":"https://doi.org/10.1186/s12879-026-12636-9","workflowStages":[]},"version":"v1","identity":"rs-7895735","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7895735","identity":"rs-7895735","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}