Tuberculous Spondylitis Caused by Intravesical Bacillus Calmette-Guerin Therapy.

A 74-year-old man underwent intravesical bacillus Calmette-Guerin (BCG) therapy for bladder cancer and later presented with lower left back pain. Magnetic resonance imaging of the spine showed high signal intensity, diagnosed as a cystic lesion in the epidural and bilateral intestinal psoas muscle. A computed tomography-guided needle biopsy and histological examination revealed bacteria from the family Mycobacteriaceae, and Mycobacterium bovis was identified using multiplex polymerase chain reaction. If lower back pain appears in a patient who has undergone BCG therapy, it is necessary to test for tuberculous spondylitis. In addition, QuantiFERON is useful for the differential diagnosis of M. bovis BCG infection.