Six consecutive children with proven purulent pericarditis were treated with pericardial irrigation with streptokinase. Mean (SD) 861 (678) ml (range 240-2000) of thick purulent fluid was drained, and five children had complete clearance of the pus within 3-8 days. One child developed intrapericardial haemorrhage with a submitral pseudoaneurysm and underwent patch closure of the neck of the aneurysm as well as anterior pericardiectomy. Follow up of 13 to 30 months revealed no pericardial constriction.