A typical tuberculosis of the wrist joint and flexor-extensor tendon sheaths: A case report

Rationale: Tuberculous tenosynovitis and arthritis of the wrist are a rare condition that are frequently misdiagnosed due to their nonspecific clinical, serological, and radiological presentations, which often mimics other diseases such as pigmented villonodular synovitis (PVNS). This case highlights the critical diagnostic challenges and the importance of maintaining a high index of suspicion for tuberculosis (TB) in atypical musculoskeletal presentations. Patient concerns: One patient presented with chronic wrist pain, swelling, and significantly restricted mobility of the wrist and fingers. Diagnoses: Preoperative TB-specific serological test results (γ-interferon N, P, and T) were negative. Wrist imaging (radiography, computed tomography, and magnetic resonance imaging) revealed synovial hyperplasia, bony destruction, and extensive tenosynovitis affecting both extensor and flexor tendon sheaths beyond the carpal tunnel. Chest computed tomography suggested pneumoconiosis with possible pulmonary TB, leading to a respiratory consultation that could not exclude pulmonary TB infection. The leading preoperative diagnosis was PVNS. Intraoperative frozen section during initial arthroscopy also supported PVNS. However, open surgery discovered distal radioulnar joint instability and extensive bone destruction, which were inconsistent with PVNS. The definitive diagnosis of tuberculous granulomatous inflammation was confirmed postoperatively by histopathological examination of paraffin-embedded sections. Interventions: The patient underwent initial arthroscopic exploration followed by open surgery. Postoperatively, the patient was received standard quadruple anti-TB drug therapy (isoniazid, rifampicin, pyrazinamide, and ethambutol). Outcomes: During follow-up, the patient demonstrated significant symptomatic relief and functional improvement after surgical intervention and the initiation of anti-TB chemotherapy. Lessons: This case underscores that wrist TB can closely mimic PVNS in terms of clinical, radiological, and even intraoperative frozen section findings. Key factors that should raise suspicion for TB include preoperative imaging showing bone destruction, the presence of concurrent pulmonary TB lesions, and intraoperative findings of severe bone or joint damage that are atypical for PVNS. Definitive diagnosis depends on comprehensive histopathological examination. Maintaining a high clinical suspicion is essential to avoid misdiagnosis and ensure appropriate treatment.