040. LEPROSY: UNUSUAL CAUSE OF SERONEGATIVE SYMMETRICAL INFLAMMATORY POLYARTHRITIS OF RHEUMATOID TYPE

Abstract

Background: Leprosy is an infectious disease caused by Mycobacterium leprae that involves the skin and peripheral nerves. It is an important health concern in certain areas. Early diagnosis and treatment are critical for preventing lifelong disability. Inflammatory polyarthritis is an unusual presenting symptom. Nasal discharge from untreated patients frequently contains large numbers of bacilli with high risk of transmitting the disease. Methods: We report the case of a Nepali lady, who presented with rheumatoid arthritis like picture. Results: Our patient is a 32 years old married Nepali lady, who works in a kindergarten and who was previously healthy. She presented with joint pain and swelling involving hands, wrists, feet and knees of two weeks duration with early morning stiffness. She reported no constitutional symptoms or anything to suggest connective tissue disease. She came from Nepal nine months ago. She looks well. She had pitting edema of hands and feet with a pit dark skin with inability to make a full fist. There is tenderness and swelling of wrists, MCP joints, PIP joints, MTP joints, ankles and knees. We also noticed faint erythematous, non-blenching, non-itchy macular lesions which involves face, neck and chest with no sensory loss over the lesions. There is no lymphadenopathy. Investigations: hemoglobin 8.5 mg/dl with normal WBC and platelets. Inflammatory markers raised with ESR 66, CRP 208 mg/L. U&Es, LFTs, Urine dipstick, hand X-rays were all normal. Virology screen: Parvovirus-B19 IgG Positive (IgM negative). ACCP, RF, ANA and ENA were Negative. Patient was initially treated as case of possible viral arthritis with naproxen, but with no response. Another possible diagnosis thought to be early RA, but as the history was short; we refrained from starting her on DMARDs. We also did not give her steroid as she is from Nepal and our policy is to exclude infection in such cases. We did a skin biopsy for her unexplained rash. Later on the histopathology confirmed leprosy. It showed several foci of superficial and deep epithelioid granulomata with focal extension into the subcutaneous fat and around nerves. Wade-Fite, ZN and silver stain revealed a large number of bacilli with a more diffuse histiocytic infiltrate consistent with leprosy. Immunofluorescence studies were negative. Patient was sent to the infectious disease clinic for leprosy treatment. Conclusion: Leprosy is very unusual cause of arthritis mimicking RA. High index of suspicion to exclude unusual infection including Leprosy is essential for patients coming from areas endemic with such diseases. Clinicians should look carefully for clues such as skin rash that may lead to the correct diagnosis.