Extrapulmonary Tuberculosis: Pathophysiology and Imaging Findings.

Extrapulmonary tuberculosis (TB) represents approximately 15% of all TB infections. It is difficult to diagnose on the basis of imaging characteristics and clinical symptoms, and biopsy is required in many cases. Radiologists must be aware of the imaging findings of extrapulmonary TB to identify the condition in high-risk patients, even in the absence of active pulmonary infection.