Evaluating the Pediatric Ocular Surface Microbiome
Kara M. Cavuoto; Anat Galor; Ta C. Chang; Julia D. Rossetto; Eduardo Alfonso; Darlene Miller
Bascom Palmer Eye Institute
Introduction: Bacteria play an important role in maintaining health throughout the human body, including the ocular surface. Although other body surfaces have been extensively studied, relatively little is known about the ocular microbiome in children. Traditional culture fails to reveal the diversity of the ocular surface microbiome; however, newer technologies that utilize bacterial genetic material may be useful.
Methods: Prospective, cross-sectional study using culture and 16S sequencing.
Results: 50 patients with an average age of 37 months (range 1-168 months) were enrolled. 47 eyes of 30 patients had a positive culture. The average age differed between culture positive and negative patients (43 vs 29 months), however was not statistically significant (p=0.19). Prior surgery did not correlate with culture growth (p=0.71). Of the 52 total isolates, Coagulase negative Staphylococcus was the most common (18/52). With 16S sequencing, Staphylococcaceae and Streptococcaceae were dominant, followed by Corynebacteriaceae and Actinomycetaceae. Older children had significantly greater diversity of the ocular surface microbiome than younger children (p=0.03). No differences were found in the observed or Shannon Diversity Index between children without prior surgery compared to unilateral or bilateral surgery (p=0.58-1.00) or right and left eyes regardless of surgery status (p=0.67-1.00).
Discussion: 16S sequencing revealed a greater variety of microbes in the ocular surface microbiome than traditional culture. Older age correlated with a more diverse microbiome. Ocular surgery does not permanently alter the microbial composition.
Conclusion: 16S sequencing is a useful tool in evaluating the complexity of the ocular surface microbiome in children, identifying a wider diversity of microbes than culture-based techniques.
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