This paper presents a statistical analysis of 37 patients with empyema treated at the Children's Hospital, Washington, D. C., from Jan. 1, 1943 to April 1, 1948, with observations on the etiology, diagnosis, therapy and complications of the disease. The criteria used in selecting cases for this study were the presence of purulent pleural fluid and positive bacteriologic findings resulting from culture of this fluid, either during life or on postmortem examination. The diagnosis was made on autopsy specimens in eight instances; two of the deaths having followed surgical procedures. Those cases having no bacteriologic proof and those following traumas or the aspiration of foreign bodies are excluded from the series. The right pleura was involved in 21 instances (56.7 per cent), the left pleura in 13 instances (35 per cent) and both pleurae in three instances (8 per cent).
During this period of five years and three months, the