Leprosy mimicking autoimmune diseases: a case series

Area of Science:

• Infectious Diseases
• Rheumatology
• Dermatology

Background:

• Leprosy, caused by Mycobacterium leprae, is a chronic granulomatous disease.
• Musculoskeletal and systemic non-specific symptoms (fever, fatigue, myalgia) can lead to misdiagnosis as autoimmune conditions.
• Leprosy can present with symptoms overlapping those of arthritis, vasculitis, and collagenosis.

Observation:

• A case series from 2019-2023 identified six patients initially investigated for autoimmune diseases who were diagnosed with leprosy.
• Patients presented with inflammatory polyarthritis, diffuse lesions, recurrent fever, arthralgia, and Raynaud's phenomenon.
• Diagnostic confirmation involved clinical evaluation, serum markers, and histopathological analysis of skin biopsies for acid-fast bacilli.

Findings:

• Six patients initially suspected of having autoimmune diseases were confirmed as leprosy cases.
• Clinical presentations included polyarthritis, skin lesions, fever, arthralgia, and Raynaud's phenomenon, mimicking rheumatologic conditions.
• Histopathological analysis of skin biopsies confirmed Mycobacterium leprae infection.

Implications:

• Physicians should consider infectious etiologies, specifically leprosy, in the differential diagnosis of suspected autoimmune diseases.
• Histopathological examination of skin biopsies is essential for accurate leprosy diagnosis.
• Early and accurate diagnosis of leprosy prevents misdiagnosis and inappropriate treatment of autoimmune conditions.