AIM: To study the composition of ocular surface microflora in patients with pterygium and to explore the correlation between ocular surface microflora and pterygium.

METHODS: Primary pterygium patients were collected from September 2018 to January 2019 in our hospital. The pterygium group consisted of 26 eyes with pterygium and the control group consisted of 9 normal eyes. We used Miseq PE301+8+8+301 platform to measure the sequences of the both ends of bacterial 16S rDNA V3-V4 region. Analyze and compare the structure and composition of microbial flora on normal ocular surface and pterygium ocular surface. WILCOX test(rank sum test)was used for statistical methods.

RESULTS: A total of 1 837 OUTs were obtained from the two groups. Alpha diversity analysis showed that the species diversity of the normal control group was higher than that of the pterygium group. At the same time, the dominant flora of the two groups were similar. Corynebacterium, Staphylococcus, Streptococcus, Propionibacterium and other Gram-positive bacteria were the main constituents, followed by Gram-negative bacteria. Corynebacterium increased in pterygium group.

CONCLUSION: The diversity of ocular surface species decreased in pterygium group, and the abundance of Corynebacterium in ocular surface flora increased significantly in pterygium patients. Corynebacterium may participate in the regulation of ocular surface immune status, and affect the occurrence and development of pterygium.