Comparative analysis of the ocular surface microbiome in type-1, type-2 diabetes mellitus and healthy individuals

Ocular health greatly impacts the quality of life, and diabetes mellitus (DM) is a major cause of several visual diseases. Likewise, microbiomes have a pivotal role in eye health. The aim was to study the effect of DM, both type-1 (T1DM) and type-2 (T2DM) on the ocular microbiome.A total of 70 subjects were recruited for this study and divided into two main groups healthy nondiabetic (n = 18) and diabetic (28 T1DM and 24 T2DM). The ocular surface (OS) microbiome was more diverse in the healthy group than in the diabetic one. Taxonomic analysis revealed Proteobacteria as the main phylum (healthy nondiabetic 41.8%, T1DM 50.6%, and T2DM 52.5%), besides Streptococcus (healthy nondiabetic 16%, T1DM 26.75%, and T2DM 29.20%) and Paracoccus (healthy nondiabetic 17%, T1DM 34.85%, and T2DM 37.47%) as the main genera. No significant diversity was found between T1DM and T2DM on both phylum and genus levels; yet genera Brevundimonas and Leptotrichia were more significantly predominant in T1DM.Two pathogenic genera, Streptococcus and Paracoccus, were more predominant in the DM group than in the healthy one.