Children with recurrent pneumonia usually have an underlying cause for it. A report from the Hospital for Sick Children in Toronto (Abdullah F Owayed et al. Archives of Pediatrics and Adolescent Medicine 2000;154:190–4) is said to include the largest series of recurrent pneumonia in children so far described.

 A retrospective study of children admitted to the hospital between 1987–97 included 2952 with pneumonia, of whom 238 (8%) had recurrent pneumonia (at least two episodes within a year or three over any period of time). An underlying cause was found in 220 (92%) of these children. These causes had been known before the child developed pneumonia in 178 (81%) cases, was diagnosed at the time of the first episode of pneumonia in 25 (11%), and during or after a recurrence in 17 (8%). The most common underlying factor was oropharyngeal incoordination and aspiration (114 children (48%)). Almost half of these children had cerebral palsy. Their mean age at diagnosis of recurrent pneumonia was 6.3 years and all had pneumonia affecting more than one lung lobe. Other underlying problems were immune disorder (34), congenital heart disease (22), asthma (19), respiratory tract anomalies (18), and gastro-oesophageal reflux (13). No underlying cause was found in 18 children. Thirteen of the children with abnormal immune function had malignant disease, 10 had sickle cell disease, and five had HIV infection. Of the 17 children whose underlying problem was only diagnosed after recurrent pneumonia, seven had asthma, four had oropharyngeal incoordination and aspiration, three had gastro-oesophageal reflux, two had airway anomalies, and one had an immune disorder. (Children with cystic fibrosis were excluded from the series.)

 Children with recurrent pneumonia should be assessed with these findings in mind. Possible underlying causes will be suggested by clinical findings and the age of the child. In this series, bilateral interstitial pneumonia onx ray was suggestive of HIV infection.