A 36-year-old man presented to our emergency department with a 6-month history of thoracic back pain. He was born in Ghana and moved to live in the United Kingdom 8 years ago.

Over the preceding 3 months, he had gradually developed symmetrical masses on either side of the thoracic spine (A and B). He denied any respiratory symptoms, fever, sweats or weight loss. On examination, he was afebrile and both masses were fluctuant but not tender or inflamed. Spinal movement was unrestricted and no features of spinal cord compression were present.

Blood tests showed a normal white cell count and differential, a C-reactive protein level of 180 mg/L (reference range, 0–4 mg/L), and an erythrocyte sedimentation rate of 64 mm/h (reference range, 0–15 mm/h). HIV serology was negative. Magnetic resonance imaging of the thoracic cord showed large, bilateral collections within the rectus spinae muscles extending between T3 and T10, and destruction of the spinous process of T5. There was also high signal in the facet joints at this level, suggesting an infection arising from them (C).

About 400 mL of pus was drained percutaneously; auramine staining showed this contained acid-fast bacilli. Fully sensitive Mycobacterium tuberculosis was subsequently cultured. Standard quadruple anti-tuberculous therapy was commenced, and percutaneous aspiration was repeated for re-accumulation of the collections.

The masses had resolved on clinical review after 3 months.

A

B

C