Epidemiological study of bacterial neonatal conjunctivitis in Imam Hossein, Resalat and Shahid Akbar Abadi hospitals, Tehran, 2001-2

The present study was performed to determine the epidemiological characteristics of bacterial neonatal conjunctivitis in three hospitals (Imam Hossein, Resalat and Shahid Akbar Abadi) from 2001 to 2002.

This descriptive study was conducted on all 3140 neonates, born in the aforementioned hospitals, between January 2001 and September 2002. Having obtained a written consent, initial data was collected by asking mothers and referring to the hospital records. Then, for cases with conjunctivitis, samples were obtained by sterile swab from inferior cul de' sac and conjunctival discharges, for direct smears, Gram and Geimsa stains, and also for culturing on blood agar, chocolate agar and thioglycolate media. Additionally, specimens were sent to Health Faculty of Tehran University for chlamydial study by direct immunofluorescent (DIF). On discharge mothers were requested to return with their babies in case of any abnormal ophthalmologic signs. In addition, they were contacted by telephone so that no infant with eye problem should be missed. Finally, data were analyzed by descriptive statistics.

Of 3140 neonates, 1699 (54.1%) were male. 170 neonates had presented with signs of conjunctivitis (5.4%), of these, 82 (48%) had negative culture. The remaining positive cultures were as below: 26(15%) coagulase negative staphylococcus, 23(13.5%) staphylococcus epidermis, 13(8%) E. coli and 10(6%) staphylococcus aureus. Of 170 samples, 10(6%) were positive for Chlamydia, among which, 6 were culture positive for bacteria and 4 were reported as DIF positive.

Regarding the previously reported prevalence of neonatal conjunctivitis (1.64% to 66.5%) the prevalence of 5% in our study shows an acceptable result. Gram positive cocci were the most frequent type of microbial infections. It should be kept in mind that the results of bacterial cultures were negative in 48% of neonates despite positive signs of conjunctivitis. The lower rate of chlamydial neonatal conjunctivitis in our society as compared to western countries may be dues to lower prevalence of sexually transmitted infections in our country.