Abstract
Purpose :
We have previously found that the ocular surface microbiome (OSM) can differ between each eye in approximately half of patients and healthy controls. In addition, we observed that the OSM was less diverse in patients with several ocular surface diseases (OSDs) compared to controls. However, longitudinal data has been lacking in these OSDs to understand the stability of the microbiome. We performed prospective, longitudinal observational studies to characterize the ocular surface microbiome OSM in OSDs.
Methods :
Sterile swabs were used to collect samples from each eye of patients. Sterile technique and multiple controls were used to assess contamination during DNA extraction, amplification and sequencing using V4 primers of the 16S rRNA gene. Concurrent use of topical antibiotics, steroids, and bandage contact lenses (BCLs) was documented.
Results :
Despite the low biomass of the ocular surface, we can detect a microbiome in ~50% of eyes sampled using sequencing. We observed that approximately half of patients had distinct microbiomes in each eye despite the eyes having similar diversity measures. In Steven’s Johnson Syndrome (SJS), there were 5 ocutypes (defined as distinct microbiome communities) with the ocutypes being dominated by Corynebacterium, Achromobacter, Stenotrophomonas, Staphlococcus or a diverse population with no dominant genera. The Corynebacterium and Staphylococcus ocutypes were observed in other OSDs as well. Human pathogens not previously associated with SJS that were found included Achromobacter, Stenotrophomonas and Sphingobacterium. Alpha diversity was lower in SJS and DED patients compared to healthy controls and GVHD patients. Next, we performed longitudinal analysis of SJS patients and observed several interesting patterns, however, only 14% of eyes showed a stable microbiome over several weeks.
Conclusions :
About half of patients had similar microbiomes in each eye. Microbiomes from OSDs had lower alpha diversity compared to controls. Longitudinal analysis has found that only 14% of eyes had a stable microbiome over time, suggesting global measurements for the microbiome, such as alpha diversity, may be more useful to define the OSM.
This is a 2021 ARVO Annual Meeting abstract.