Primary purulent bacterial pericarditis due to Streptococcus intermedius in an immunocompetent adult: a case report

BACKGROUND: Acute purulent bacterial pericarditis is of rare occurrence in this modern antibiotic era. Primary involvement of the pericardium without evidence of underlying infection elsewhere is even rarer. It is a rapidly progressive infection with high mortality. We present an extremely rare case of acute purulent bacterial pericarditis in an immunocompetent adult patient with no underlying chronic medical conditions. CASE PRESENTATION: A 33-year-old previously healthy white man presented with the complaints of chest pain and dyspnea. He was diagnosed as having acute pericarditis and was discharged home on indomethacin. Over a period of 2 weeks, his symptoms worsened gradually and he was readmitted to our hospital. He was found to have large pericardial effusion with cardiac tamponade. An urgent pericardiocentesis was done with drainage of 550 ml of purulent material. Cultures grew Streptococcus intermedius confirming the diagnosis of acute purulent bacterial pericarditis. No other focus of infection was identified on imaging workup suggesting primary infection of the pericardium. His clinical course was complicated by development of constrictive pericarditis for which he underwent surgical pericardiectomy. He received a total of 7 weeks of intravenously administered antibiotics with complete clinical recovery. CONCLUSIONS: Acute purulent bacterial pericarditis, although rare, should always be kept in mind as a possible cause of pericarditis. Early recognition and prompt intervention are important for a successful outcome.