A chronological study of the bacterial pathogen changes in acute neonatal bacterial conjunctivitis in southern China

Background: The aim of the project is to retrospectively study the changes in bacterial pathogens in acute neonatal bacterial conjunctivitis from 2002 to 2016 in Southern China. The results may provide the guidance for drug choice for acute neonatal bacterial conjunctivitis. Methods: Secretion specimens for bacterial culture were taken from 485 cases with clinically diagnosed acute bacterial neonatal conjunctivitis. Bacterial pathogens were detected by Gram staining and subsequent bacterial culture. Results: From the analysis of the bacterial pathogens in 485 cases of acute neonatal conjunctivitis patients from 2002 to 2016 in Southern China, there is an overall trend of decreasing detection of Gram-positive bacteria and increasing detection of Gram-negative bacteria from the conjunctival sac secretions. Gram-positive bacteria in the bacteria-positive samples dropped year by year from 82.6% in 2002 to 72.4% in 2016. Accordingly, the ratio of Gram-negative bacteria increased from 17.4% in 2002 to 27.6% in 2016. Of note, despite the overall trend, there was a significant increase in detection of Gram-positive bacteria and decrease in detection of Gram-negative bacteria from 2011 to 2012. Among the Gram-positive bacteria, there is a trend of increasing percentage of the opportunistic pathogens ( an similar to 60% increase in Staphylococcus epidermidis and Staphylococcus saprophytic) and decreasing percentage of Staphylococcus aureus (similar to 30% decrease) and hemolytic streptococcus (similar to 20% decrease) in the last 15 years. The main Gram-negative bacterium is Neisseria gonorrhoeae. Overall, there is a change in the pattern of bacterial species in acute neonatal bacterial conjunctivitis in Southern China in the last 15 years. Conclusion: Our study provides a trend analysis of the bacterial pathogens in the conjunctival sac secretions of the acute neonatal bacterial conjunctivitis patients in Southern China in recent years. This data could provide useful information regarding the treatment options for neonatal bacterial conjunctivitis.