Diabetic Retinopathy Affects Intraocular Microbiome For Patients With Diabetes

The intraocular microbiome differs between people with diabetes mellitus with and without diabetic retinopathy, according to research published in Ophthalmology and Therapy.

Researchers conducted a prospective controlled pilot study to compare the microbiome in the aqueous humor and gut of people with diabetes mellitus with and without diabetic retinopathy.

The study included a total of 12 people who underwent intraocular surgery: 4 healthy control participants, 4 individuals with diabetes mellitus without diabetic retinopathy, and 4 individuals with diabetes mellitus and diabetic retinopathy. Aqueous humor samples were collected during surgery, and stool samples were obtained in the perioperative period. The researchers assessed gut and aqueous humor samples using ribosomal RNA gene sequencing.

The researchers observed minor differences at the phyla level among the 3 groups, but found 3 distinct clusters with discriminatory genera on heat map analysis. They found genera-level clustering was more apparent for intraocular than gut microbiome. 

The researchers also identified genera unique to the eye or the gut in people with diabetes mellitus and diabetic retinopathy. Additionally, they observed a consistent reduction in the abundance of anti-inflammatory bacteria in people with diabetes mellitus and diabetic retinopathy, compared to those with diabetes mellitus without diabetic retinopathy.

“Our preliminary results show that an intraocular microbiome exists in health and disease. Furthermore, dysbiosis of the aqueous humor has distinctive features compared with the gut,” the researchers explain.

Limitations included the small sample sizes and differences in baseline characteristics among the groups.

This article originally appeared on Ophthalmology Advisor