Afebrile pneumonia associated with chlamydial infection in infants less than 6 months of age: initial results of a three year prospective study.

During the year 1986-1988, 112 infants younger than 6 months of age with the diagnosis of afebrile pneumonia were studied at Chulalongkorn Hospital, Bangkok, Thailand. Thirty cases (26.78%) were caused by Chlamydia trachomatis. The clinical and laboratory findings which differed significantly from pneumonia caused by other organisms included longer duration of symptoms (greater than 1 week), younger age of onset (less than 12 weeks), history of conjunctivitis after birth, no wheezing detected, white blood cell count greater than or equal to 10,000 cells/microliters with eosinophilic count greater than or equal to 300 cells/microliters and reticulonodular infiltration on the chest x-ray.