Infectious mimics of rheumatoid arthritis.

Rheumatoid arthritis (RA) can have various infectious mimics. As immunosuppressive agents used in treatment can aggravate the underlying infections, correct diagnosis of RA and ruling out infections is important. Numerous viral infections (Parvovirus B19, Hepatitis B, Hepatitis C, Chikungunya and other alphaviruses, human immunodeficiency virus (HIV) and various other viruses), mycobacterial infections (Poncet's disease, tubercular septic arthritis, and leprosy), bacterial arthritis, brucellosis and Lyme disease are among common infections that mimic RA. Widespread travel and tourism, especially to exotic areas, high risk sexual behavior and widespread use of immunosuppressive and chemotherapeutic agents has led to numerous outbreaks of infections in areas where these infections were never reported before. Hence, rheumatologists all over the world should be familiar with musculoskeletal manifestations of infections. History of travel, comorbid fever, skin rash, genital ulcers, urethral discharge, the consumption of unpasteurized milk, lymphadenopathy, tenosynovitis, low platelet count, and positive Mantoux test can offer potential diagnostic clues. Serological testing, cultures, specific radiological signs and deoxyribonucleic Acid (DNA) amplification techniques often aid in diagnosis. Treatment mainly consists of antimicrobial agents, analgesics, and nonsteroidal anti-inflammatory drugs (NSAIDs). However, immunosuppressive agents including steroids and disease modifying anti-rheumatic drugs (DMARDs) are needed occasionally in different refractory and prolonged illnesses. Most of the times, episodes of arthritis are self-limiting and respond to treatment of underlying cause. However, few infections like Chikungunya and Lyme's disease can lead to chronic arthritis as well.