Pure neural leprosy or amyloid neuropathy? systematic review and clinical case report

Abstract

Objective: To review the literature, including a clinical case discussion with suspicion of pure neural leprosy and final diagnosis of amyloid neuropathy. Methods: The study was conducted on May 28, 2020. A systematic review of the literature was conducted, with searches in PubMed, Medline, Lilacs and BVS MS using the descriptors: neuritic leprosy, pure neural leprosy, primary neural leprosy, pure neuritic leprosy, amyloid polyneuropathy, amyloid neuropathies, amyloid polyneuropathy. Clinical trials, cohorts, cross-sectional, clinical cases and case studies, published in Portuguese, English or Spanish between 2010 and 2020 were included. Then, a case report with an initial suspicion of pure neural leprosy was presented. Laboratory tests, electroneuromyography, ultrasound and biopsy of the sural nerve were requested. Results: 23 scientific texts were included. No publications with the two themes together were found. Diagnosis of pure neural leprosy and the possibility of using auxiliary resources were the most prominent themes in the studies. In the clinical case, the patient’s electroneuromyography showed sensitive and motor polyneuropathy of lower limbs, symmetrical, of moderate intensity, of the mixed type (axono- demyelinating), sensitive and axonal. Ultrasonography of the sural nerve revealed changes in the contour of the deep fibular nerves and biopsy of the sural nerve demonstrated the accumulation of amorphous eosinophilic material in the nerve path and Congo red staining showed birefringence of the deposit in applegreen under polarized light. The final diagnosis was amyloidotic neuropathy. Conclusion: Clinical diagnosis was amyloidotic neuropathy. Diagnosis of pure neural leprosy in endemic areas of Brazil is a challenge for the health system.