Multibacillary Leprosy With Accelerated Progression: A Case Report of an Atypical Clinical Presentation and Therapeutic Approach.

Leprosy, or Hansen's disease, remains a public health concern, especially in endemic regions and among migrant populations. This case involves a patient from Venezuela living in Peru who initially presented with fever, weight loss, and respiratory symptoms without radiological findings. Physical examination revealed multiple erythematous nodules, hypopigmented macules, and thickened peripheral nerves. A skin smear confirmed multibacillary leprosy. The patient began standard multidrug therapy and showed gradual improvement. However, by the third month, he developed erythema nodosum leprosum (type 2 reaction), which was successfully treated with thalidomide without interrupting the main regimen. Follow-up showed complete resolution of skin lesions and neurological recovery. This case highlights an atypical presentation of multibacillary leprosy mimicking a respiratory infection. It emphasizes the importance of clinical suspicion in non-endemic areas with high migration rates. Early diagnosis and treatment are key to preventing permanent complications. Strengthening epidemiological surveillance and comprehensive care are essential for effective control of Hansen's disease.