Etiological features of bacterial keratitis in patients with diabetes mellitus
Background. The purpose was to study etiological features of bacterial keratitis in patients with type 1 diabetes mellitus. Materials and methods. The analysis was performed on the basis of survey data of 62 patients with bacterial keratitis and type 1 diabetes mellitus and 43 individuals with bacterial keratitis without diabetes mellitus of the corresponding age (control group). In addition to standard ones, ophthalmic methods included fluorescein test, anterior segment optical coherence tomography, non-contact corneal aesthesiometry, bacteriological examination: culture from the conjunctival cavity to dense nutrient media (5% blood agar and medium for sterility control), microscopic examination of conjunctival smear with Romanowsky-Giemsa and Pappenheim stain. Results. Etiological features of bacterial keratitis were found in patients with diabetes mellitus: Gram-positive microflora was the causative agent 1.5 times more often, and Gram-negative — 3.1 times less often than in patients without diabetes mellitus from the control group (p < 0.05). In addition, Staphylococcus epidermidis was the causative agent of bacterial keratitis in patients with diabetes mellitus 1.9 times more often, and Pseudomonas aeruginosa — 6.3 times less often than in patients of the control group (p < 0.05). Conclusions. There are etiological features of bacterial keratitis in patients with diabetes mellitus, namely predominance of the Gram-positive microflora among the pathogens due to Staphylococcus epidermidis.