Abstract 11428: A Spot(s) Diagnosis: A Rare Cause of Effusive-Constrictive Pericarditis

Introduction: Effusive-constrictive pericarditis (ECP) is a rare cause of heart failure characterized by impaired cardiac filling due to pericardial compression. Cutibacterium acnes (C. acnes) is an indolent bacteria and uncommon cause of pericarditis, occurring predominantly in older, immunocompromised, and post-surgical patients. This report describes a rare case of ECP due to C. acnes in a young, immunocompetent male. Case Description: A 26 year old male with a history of acne treated with clindamycin wash presented with progressive dyspnea, orthopnea and lower extremity edema. Exam found a pericardial friction rub and knock, and Kussmaul sign. Electrocardiogram met low voltage criteria. Chest CT demonstrated bilateral pleural effusions, pericardial effusion, and ascites. Transthoracic echocardiogram showed a complex pericardial effusion with evidence of tamponade physiology. An emergent pericardial window was performed revealing thickened pericardium, pericardial adhesions, and 200 mL of sanguineous fluid. Pericardial biopsy was consistent with chronic fibrosing pericarditis. Tissue culture isolated C. acnes. Subsequent right heart catheterization confirmed constrictive physiology with diastolic equalization of intracardiac pressures and ventricular interdependence. Cardiac MRI noted intense pericardial enhancement, septal bounce, and biventricular fixation. Rheumatologic, HIV, viral hepatitis, EBV and CMV panels were negative. ESR was normal and CRP mildly elevated. The patient was treated with diuretics, colchicine, metoprolol, and antibiotics. Subsequent imaging showed marked improvement (Figure 1). Discussion: This case demonstrates that ECP due to C. acnes can occur in an immunocompetent patient without traditional risk factors or exposures. Since bacterial pericarditis is associated with a significant risk of mortality, it is important to have a high suspicion for this pathogen to avoid delay of appropriate treatment.