Abstract:AIM:To investigate the compositional and structural differences in the ocular surface microbiota of patients with primary pterygium during the progressive and stationary stages, and to identify key microbial biomarkers associated with pterygium progression.
METHODS: A cross-sectional study design was adopted. Patients with progressive pterygium(PPG group), stationary pterygium(SPG group), and age- and sex-matched healthy volunteers(HCG group)were enrolled. Conjunctival swabs were collected from the affected eye(or the healthy eye in controls)of each participant. 16S rRNA gene amplicon sequencing of the V3V4 region was performed. The analytical workflow encompassed rarefaction curve analysis, Alpha/Beta diversity analyses, ASV analysis. LEfSe analysis and the Kruskal-Wallis H test were used to screen differential microbiota.
RESULTS: Final enrollment included 28 patients(28 eyes)in each group: PPG(11 males, 17 females; mean age 60.54±8.44 y), SPG(10 males, 18 females; mean age 61.82±10.21 y), and HCG(12 males, 16 females; mean age 64.07±7.27 y). No significant differences were found among the three groups in baseline characteristics(all P>0.05). The number of valid sequences and the rarefaction curves confirmed sufficient sequencing depth. Alpha/Beta diversity analyses showed no statistically significant differences among the three groups(all P>0.05), indicating that the overall structure of the ocular surface microbiota was relatively stable. LEfSe analysis(LDA score>3.0)revealed that the Propionibacteriales, the Propionibacteriaceae, the Cutibacterium and the Comamonadaceae were significantly enriched in the PPG group. Following Kruskal-Wallis H tests with Bonferroni correction for multiple comparisons, the relative abundances of Propionibacteriales, Propionibacteriaceae, and Cutibacterium were significantly higher in PPG group than in the HCG group(all PSymbol|@@0.05), but did not differ significantly between the PPG and SPG groups(all P>0.05). The abundance of Comamonadaceae was significantly higher in SPG group than in HCG group(PSymbol|@@0.05), whereas PPG group not differ from either group(all P>0.05).
CONCLUSION: Cutibacterium, the representative genus of the propionibacterial group, tends to be enriched in eyes with progressive pterygium, indicating a potential association between this genus and pterygium progression.