Seronegative Bilateral Symmetrical Inflammatory Polyarthritis: Think Twice Before Starting Immunosuppression

摘要

The most common cause of bilateral symmetrical polyarthritis in the small joints is rheumatoid arthritis. However, if seronegative arthritis is involved, it could be the case that other underlying causes need to be diagnosed. This is particularly important for those coming from or living in developing countries where infectious causes should always be considered. The case of a young Nepali woman is presented in this article. She was referred as a case of seronegative rheumatoid arthritis for DMARDs therapy but this was not the case due to her origin from Nepal and seronegativity for RF, Anti-ccp, and ANA as well as faint macular skin lesions over her face and upper extremities, which the patients are not aware of. Consequently, skin biopsy was carried out which subsequently confirmed that the infectious cause of her polyarthritis was leprosy.LEARNING POINTS class="unordered" style="list-style-type:disc">Bilateral symmetrical seronegative inflammatory arthritis of rheumatoid type is very common.However, when both RF and anti-ccp are negative, other possible secondary causes including infection should be considered, especially in patients from areas where disease is endemic.In this case lepromatous leprosy was the cause of the patient’s presumed rheumatoid arthritis and all her arthritis resolved after her leprosy had been treated. class="kwd-title">Keywords: Seronegative rheumatoid arthritis, leprosy class="head no_bottom_margin" id="__sec2title">INTRODUCTIONLeprosy (also known as Hansen's disease) is an infectious disease caused by Mycobacterium leprae that involves the skin and peripheral nerves. Leprosy is a significant global health concern in certain areas. Early diagnosis and a full course of treatment are critical for preventing lifelong neuropathy and disability.The prevalence of leprosy varies. The overwhelming majority of cases are found in developing countries. Of the 16 countries reporting more than 1000 new cases annually in 2009, the largest numbers of new cases were seen in India, Brazil, Indonesia, Bangladesh, and Nigeria. However, since international travel is increasing, patients with leprosy may present anywhere^[].The disease probably spreads via the respiratory route. Nasal discharge from untreated patients with lepromatous (multibacillary) disease frequently contains large numbers of bacilli^[].We report this case to raise awareness among general practitioners and rheumatologists of infectious causes, including leprosy, when dealing with patients from developing countries presenting with presumed seronegative rheumatoid arthritis as the two different conditions require totally different treatment.