Tuberculous Pericarditis: Is It Contagious?

Tuberculous pericarditis is a condition where the pericardium, the double-layered sac around the heart, becomes infected with tuberculosis. In itself, isolated tuberculous pericarditis is generally not considered contagious. However, the potential for transmission depends largely on the source of the tuberculosis infection.

Understanding the Source of Infection

If the pericardial infection stems from a primary tuberculosis focus in the lungs or pleura, and the infection spreads via the bloodstream to the pericardium, then the condition may be associated with contagious tuberculosis. In such cases, the patient may also be actively shedding the bacteria through respiratory secretions, especially if pulmonary tuberculosis is present.

Demographics and Symptoms

Tuberculous pericarditis predominantly affects young adults, with a higher incidence in males. The onset is typically gradual, and symptoms may include fever, chest pain, cough, shortness of breath, loss of appetite, weight loss, fatigue, and night sweats.

Signs of Associated Pulmonary Tuberculosis

When the condition is accompanied by primary pulmonary tuberculosis, symptoms such as persistent cough and hemoptysis (coughing up blood) may be present. Key physical findings include tachycardia, and during the exudative phase of the disease, a pericardial friction rub may be audible. Approximately 40% to 50% of patients develop pleural effusion.

Cardiac Manifestations

Physical examination may reveal an enlarged cardiac dullness to percussion, distant heart sounds, and in cases of significant effusion, signs of cardiac tamponade. A classic triad known as Beck's triad—low blood pressure, muffled heart sounds, and jugular venous distention—can be indicative of severe pericardial involvement.

Diagnostic Approaches

Laboratory tests often show a positive tuberculin skin test. Early pericardiocentesis typically reveals a fibrinous and blood-tinged exudate. While white blood cell counts may be normal or slightly elevated, lymphocytic predominance is common. Although Mycobacterium tuberculosis can sometimes be identified in the fluid, the yield is generally low.

Advanced Diagnostic Tools

Pericardial biopsy may reveal caseating granulomas, which are characteristic of tuberculosis. Echocardiography is a valuable tool in confirming the presence of pericardial effusion and assessing its severity.