Case of arthritis secondary to leprosy

Leprosy is a chronic granulomatous infectious disease, which is caused by Mycobacterium leprae. High numbers of people are still affected by this disease in some of the developing countries however, it is rarely seen in non-endemic regions. Cutaneous and neurological manifestations are the common and classical presentations of leprosy. Musculoskeletal involvement is the third most common manifestation but is less frequently reported. Joint involvement can present as acute symmetrical polyarthritis or chronic polyarthritis resembling rheumatoid arthritis. Leprosy can also present with tenosynovitis, either isolated or associated with arthritis.

We report a case of 29-year-old man who developed tenosynovitis and acute symmetrical polyarthritis including small joints of hands and feet three weeks after appearance of typical cutaneous lesion of leprosy. Patient improved with steroid and anti leprosy treatment. Patient had another acute episode with symmetrical polyarthritis four months later while on treatment.

In the modern era, there is increase movement of population from developing countries to developed countries, it is likely that patient suffering from leprosy with arthritis may present to rheumatology clinic in those countries where leprosy is not endemic. Exact pathogenesis for musculoskeletal manifestations is still not fully known. Our patient presented with symmetrical polyarthritis, enthesitis and systemic involvement, which was secondary to lepra reaction. Having good knowledge of musculoskeletal manifestation of leprosy, will help narrow differential diagnosis and will prevent unnecessary diagnostic workup.

Leprosy can present with different rheumatologic manifestation including tenosynovitis and acute symmetrical polyarthritis. Type 2 lepra reaction (Erythema nodosum leprosum ENL) can present with systemic manifestation and can involve skin, nerves, joints, kidneys and liver.