Unusual aetiology of persistent back pain in a patient with multiple myeloma: infectious discitis.

A 47 year old man with multiple myeloma presented with persistent back pain caused by infectious discitis. Aspiration of the affected vertebral disc space was carried out, guided by computed tomography, and microbiological examination of the aspirate revealed Staphylococcus aureus and Mycobacterium tuberculosis. Antituberculous and antistaphylococcal antibiotic treatment resulted in a dramatic clinical response with complete resolution of the vertebral abscess. Detailed radiological and microbiological investigations are necessary to diagnose unusual causes of chronic bone pain such as discitis or infectious bone disease in patients with multiple myeloma.