A modern approach to tuberculous pericarditis.
The human immunodeficiency virus (HIV) epidemic has been associated with an increase in all forms of extrapulmonary tuberculosis including tuberculous pericarditis. Tuberculosis is responsible for approximately 70% of cases of large pericardial effusion and most cases of constrictive pericarditis in developing countries, where most of the world's population live. However, in industrialized countries, tuberculosis accounts for only 4% of cases of pericardial effusion and an even smaller proportion of instances of constrictive pericarditis. Tuberculous pericarditis is a dangerous disease with a mortality of 17% to 40%; constriction occurs in a similar proportion of cases after tuberculous pericardial effusion. Early diagnosis and institution of appropriate therapy are critical to prevent mortality. A definite or proven diagnosis is based on demonstration of tubercle bacilli in pericardial fluid or on histologic section of the pericardium. A probable or presumed diagnosis is based on proof of tuberculosis elsewhere in a patient with otherwise unexplained pericarditis, a lymphocytic pericardial exudate with elevated biomarkers of tuberculous infection, and/or appropriate response to a trial of antituberculosis chemotherapy. Treatment consists of 4-drug therapy (isoniazid, rifampicin, pyrazinamide, and ethambutol) for 2 months followed by 2 drugs (isoniazid and rifampicin) for 4 months regardless of HIV status. It is uncertain whether adjunctive corticosteroids are effective in reducing mortality or pericardial constriction, and their safety in HIV-infected patients has not been established conclusively. Surgical resection of the pericardium is indicated for those with calcific constrictive pericarditis or with persistent signs of constriction after a 6 to 8 week trial of antituberculosis treatment in patients with noncalcific constrictive pericarditis.