Chlamydia trachomatis and respiratory disease in infants.

Eleven infants under six months of age with respiratory symptoms and positive results of serological tests for Chlamydia trachomatis, including an infant from whom chlamydiae were isolate, are presented. The three distinct patterns of illness in these infants were a bronchitis with paroxysmal coughing, a bronchiolitis syndrome, and a diffuse afebrile pneumonia. We conclude that chlamydial respiratory disease should be considered in Australian infants with the described features. The diagnosis can be confirmed by immuno-fluorescence.