CASE BASED REVIEW Leprosy in a rheumatology setting: a challenging mimic to

Abstract Leprosy can manifest arthritis both as a complica-tion and a comorbid disorder and can be a challenging differ-ential diagnosis in rheumatology practice due to several common features. Uncommonly, it may present as acute se-vere polyarthritis with skin lesions and neurological deficit or a digital vasculitis and gangrene. We demonstrate this profile in a retrospective case series analysis of 33 patients (13 females, median age 55 years) in a community-based clinic setting over the period 1998–2012; an electronic search of case records of 41,000 patients was carried out. Rheumatoid arthritis (RA) coexisted in seven patients (three lepromatous, two tuberculoid, and two polyneuritic). Serological rheuma-toid factor and antinuclear antibody were often false positive. Several patients of RAwere on long-term supervised metho-trexate. Rheumatologists should be aware of this clinical mimic to avoid errors in diagnosis and management