A Rheumatoid Arthritis-Like Presentation in Multibacillary Leprosy with Concurrent Erythema Nodosum Leprosum

Leprosy is a chronic infectious disease caused by a Mycobacterium leprae (M.leprae), continues to be a diagnostic challenges because of its rarity and diverse clinical manifestations. Classic erythema nodosum leprosum (ENL) typically presents in patients with preexisting borderline lepromatous or lepromatous leprosy. This case report discusses the atypical presentation of ENL in a 69-year-old woman who experienced intermittent crops of red nodules with fever, accompanied by glove and stocking anesthesia, joint deformities without clinical evidence of classic multiple symmetrical papulonodular lesions of lepromatous leprosy. The initial diagnosis of rheumatoid arthritis, followed by treatment with Disease-modifying antirheumatic drugs, failed to provide symptom relief, leading to further investigation. Biopsy results and slit skin smears confirmed multibacillary leprosy with necrotizing suppurative vasculitis, and special stains confirmed the presence of M. leprae. Multidrug therapy was initiated, resulting in an initial improvement in symptoms. This case report emphasizes the importance of considering leprosy with erythema nodosum leprosum in the differential diagnosis for patients presenting with rheumatoid arthritis-like symptoms, particularly in atypical clinical manifestations and when there is no response to standard treatments.