Respiratory syncytial virus is the most common pathogen causing lower respiratory tract infection in infants. Respiratory syncytial virus infection is also associated with a number of extrapulmonary manifestations, including the cardiac system. Pericardial effusion, however, is a very rare occurrence with respiratory syncytial virus infection. We report a very young infant with respiratory syncytial virus bronchiolitis whose clinical course was associated with pericardial effusion, treated conservatively.
