Etiology and diagnosis of neonatal conjunctivitis.

Chlamydia trachomatis was isolated from the most inflamed eye of 13 of 107 (12%) infants with neonatal purulent conjunctivitis and from none of 100 healthy infants (p less than 0.01). Staphylococcus aureus was recovered from 49 (46%) inflamed eyes and from 8 (8%) healthy eyes (p less than 0.01). Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis, Escherichia coli and Klebsiella pneumoniae were isolated from very few infants with conjunctivitis but not from controls. No organisms could be recovered from 23 (22%) infants with conjunctivitis and from 60 (60%) healthy infants (p less than 0.01). The incidence of neonatal purulent conjunctivitis was 107 (2%), of 5,924 births. Eyes infected with C. trachomatis were significantly more inflamed than eyes from which S. aureus or no organisms could be isolated. Furthermore, conjunctival "pseudomembranes" were associated with C. trachomatis. The age at onset of the chlamydial conjunctivitis was higher compared to the age at onset of conjunctivitis in which S. aureus or no organisms were isolated.