The clinical features are those of pericarditis with effusion, and the most common causes of hemorrhagic pericarditis are metastatic carcinoma and tuberculosis. An effusion of this size is sufficient to produce some cardiac tamponade that diminishes cardiac output; the paradoxical drop in pressure (more than 10 mm Hg) is called pulsus paradoxus and can be caused by pericarditis and by tamponade. Candida is a rare cardiac infection in immunocompromised individuals. Coxsackieviruses are known to cause myocarditis. Group A streptococci are responsible for rheumatic fever; in the acute form, rheumatic fever can lead to fibrinous pericarditis, and in the chronic form, it can lead to serous effusions from congestive heart failure. Staphylococcus aureus is most often a cause of infective endocarditis.