Tuberculous tenosynovitis and ulnar bursitis of the wrist.

Tuberculous infection of the hand is a rare form of extrapulmonary tuberculosis that, left untreated, can cause serious joint and tendon damage. We report the case of a 65-year-old male patient who presented with an insidious flexor weakness of the fifth finger but without any history of trauma. Magnetic resonance imaging revealed a partial tear of the fifth finger flexor tendon with a fluid collection in the tendon sheath and in the flexor compartment along the ulnar side. Under ultrasound guidance, this fluid collection was aspirated and analyzed for Mycobacterium tuberculosis using polymerase chain reaction. The assay was positive for the microorganism, confirming the diagnosis of tuberculous tenosynovitis and ulnar bursitis of the wrist. The early suspicion and diagnosis of this extrapulmonary disease facilitated anti-tuberculous chemotherapy and helped avoid a hasty injection of corticosteroid.