Poncet's Disease-A Rare Complication of Tuberculosis: A Case Report

Objectives We present a rare case of Poncet's disease, a sterile reactive arthritis associated with active tuberculosis (TB), mimicking seronegative spondyloarthritis in a young diabetic male. We aim to highlight the diagnostic challenges and emphasize the importance of considering Poncet's disease in patients with inflammatory arthritis, especially in the context of subclinical TB. Methods We present a detailed case report of a 28-year-old male with poorly controlled diabetes mellitus type 2 [glycated hemoglobin (HbA1c) 13.9%] who presented with a 3-week history of bilateral ankle pain, swelling, and redness. The pain progressed to involve multiple small joints of the hands, wrists, elbows, and knees, significantly impacting his mobility, with no history of trauma, fever, rash, or urinary symptoms. Physical examination revealed tenderness and swelling in the affected joints with limited range of motion. Laboratory investigations showed an elevated erythrocyte sedimentation rate (ESR) of 74 mm/hour and C-reactive protein (CRP) of 104 mg/L. Chest X-ray revealed bilateral hilar lymphadenopathy, and computed tomography (CT) scan confirmed multiple enlarged lymph nodes in the mediastinum and bilateral hilar regions, suggestive of pulmonary TB. Despite the absence of acid-fast bacilli in bronchoalveolar lavage (BAL), the clinical presentation, imaging findings, exclusion of other causes of reactive arthritis, and a dramatic response to anti-TB therapy within days of initiation strongly supported the diagnosis of Poncet's disease. The patient completed 6 months of anti-TB therapy and achieved complete resolution of joint pain and swelling, regaining his full range of motion. Results The patient's symptoms, including joint pain, swelling, and inflammatory markers, significantly improved within weeks of starting anti-TB therapy. Serial CRP and ESR readings showed a downward trend, confirming the response to treatment. Conclusion This case report highlights the importance of considering Poncet's disease in the differential diagnosis of seronegative spondyloarthritis, particularly in patients with underlying TB. A high index of suspicion and prompt initiation of anti-TB therapy can lead to rapid improvement in symptoms and prevent unnecessary investigations and potentially harmful immunosuppressive medications.