Leprosy in a rheumatology setting: a challenging mimic to expose

Abstract

Leprosy can manifest arthritis both as a complication and a comorbid disorder and can be a challenging differential diagnosis in rheumatology practice due to several common features. Uncommonly, it may present as acute severe 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 rheumatoid factor and antinuclear antibody were often false positive. Several patients of RA were on long-term supervised methotrexate. Rheumatologists should be aware of this clinical mimic to avoid errors in diagnosis and management.

Leprosy in the rheumatology clinic: an update on this great mimic

“…The natural course of the condition is 1–2 weeks, but recurrences are common. ENL has been more commonly described from rheumatology units than type 1 reaction …”

Rheumatic and other musculoskeletal manifestations and autoantibodies in childhood and adolescent leprosy: significance and relevance

“…Significant MSK articular involvement is predominantly found in lepromatous forms and lepra reactions, which are somewhat less observed among pediatric cases. 9,10 Single hypo-aesthetic skin lesions, paucibacillary forms and low skin smear positivity (acid fast bacillus) appear to be hallmark of childhood cases.…”

“…9---14 The extent is largely influenced by the geographical and endemic factors and study sites; it varies considerably. 9,10,13 It is second to cutaneous and neurological manifestations http both in non-reactionary and reactionary states. Most of the MSK studies in leprosy are from Brazil and India (Table 2).…”

“…The author visited the source database of a case series report ( Table 2). 10 One case report found was that of a 19-year-old male (past history of skin psoriasis at 10 years of age) who was evaluated for an acute febrile onset of rheumatoid arthritis (RA)-like polyarthritis (seronegative for rheumatoid factor [RF]), atypical skin lesions, and a few suspicious nodules, and finally diagnosed erythema nodosum leprosum (ENL); around 1,700 rheumatic referral patients (children and adolescents) had been evaluated during the study period (1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013). A significant proportion of leprosy associated inflammatory arthritis examined by rheumatologists in leprosy clinic based study 9 was reported to closely resemble RA or spondyloarthritis (SSA).…”

“…14 To summarize, leprosy is the great mimic of the MSK-articular system and can present with protean manifestations requiring a high index of clinical suspicion to make a correct and timely diagnosis. 10,12 It is well known that leprosy patients can be flooded with antibodies. From a rheumatological perspective, it is important to recognize false positive AAb; these include RF, ANA, antibody to anti-citrullinated cyclic peptides (a-CCP), antibody to anti-neutrophilic cytoplasmic antigens (ANCA), and antiphospholipid antibodies (APL)/anti-cardiolipin antibodies (ACL).…”