The most common cause of acute pericarditis is which?

• A. Viral infection
• B. Bacterial infection
• C. Autoimmune disease
• D. Uremia

Answer: (D)

Viral infection is the most common trigger for acute pericarditis. In most cases the illness is labeled idiopathic because no specific organism is recovered, but it’s presumed to be viral—typical culprits include enteroviruses like Coxsackie B. The inflammation of the pericardium causes the characteristic symptoms and exam findings: sharp, pleuritic chest pain that often improves when leaning forward, a pericardial friction rub, and ECG changes such as diffuse ST-segment elevation with PR-segment depression. Uremia can cause pericarditis, but it occurs in the setting of advanced renal failure and is less common than viral etiologies. Bacterial pericarditis is rare and usually presents with sepsis or purulent effusion, and autoimmune pericarditis occurs but is not the predominant cause in most patients.