Tuberculous empyema.

Tuberculous empyema represents a chronic, active infection of the pleural space that contains a large number of tubercle bacilli. It is rare compared with tuberculous pleural effusions that result from an exaggerated inflammatory response to a localized paucibacillary pleural infection with tuberculosis. The inflammatory process may be present for years with a paucity of clinical symptoms. Patients often come to clinical attention at the time of a routine chest radiograph or after the development of bronchopleural fistula or empyema necessitatis. The diagnosis of tuberculous empyema is suspected on computed tomography imaging by finding a thick, calcific pleural rind and rib thickening surrounding loculated pleural fluid. The pleural fluid is grossly purulent and smear positive for acid-fast bacilli. Treatment consists of pleural space drainage and antituberculous chemotherapy. Problematic treatment issues include the inability to re-expand the trapped lung and difficulty in achieving therapeutic drug levels in pleural fluid, which can lead to drug resistance. Surgery, which is often challenging, should be undertaken by experienced thoracic surgeons.