Our aim was to compare intrapleural streptokinase (SK) treatment and simple tube drainage in the treatment of children with complicated parapneumonic pleural effusion. A retrospective review of medical records included patient demographics, clinical presentation, biochemical and microbial studies of pleural effusion, radiographic evaluation of chest tube drainage, use of fibrinolytic agents and type of surgical intervention. During the 2.5-year period (1999-2002), 53 children (29 M, 24 F) with complicated parapneumonic effusions or empyema were identified. Closed tube drainage and antibiotic treatment were administered to patients with a diagnosis of complicated parapneumonic effusion (n = 24) until October 2000; after that time point, intrapleural streptokinase was added to this regimen (n = 29). The median age at the time of presentation was 2.5 years (range: 5 months-14.6 years). There were no significant differences in terms of clinical outcomes between the two groups. The average length of hospital stay was 19.1 +/- 5.5 and 21.9 +/- 11.2 days for the drainage and streptokinase groups, respectively; the time to afebrile state after admission was 5.8 +/- 4.1 and 7.6 +/- 7.5 days. The percentage of patients who eventually required surgical intervention was 8.3% for the drainage group and 20.6% for the streptokinase group. In conclusion, in the treatment of complicated parapneumonic effusions or empyema, the adjunctive treatment with intrapleural SK does not significantly reduce durations of fever, chest tube drainage and hospital stay, and the need for surgery, regardless of the stage of the disease, compared to simple closed tube drainage.