OCULAR SURFACE MICROBIOTA IN PEDIATRIC KERATOCONUS: A COMPARATIVE OBSERVATIONAL STUDY
DOI:
https://doi.org/10.32345/USMYJ.3(164).2026.59-65Keywords:
keratoconus; microbiota; dysbiosis; pediatrics; corneal diseases; biomarkersAbstract
Aim. To compare the ocular surface microbiota composition in pediatric patients with keratoconus (KC) and healthy age-matched controls, and to assess the relationship between microbial dysbiosis and disease progression.
Materials and methods. A comparative observational study was conducted at the National Children's Specialized Hospital "Ohmatdyt". Twenty pediatric patients were enrolled: 10 with confirmed keratoconus (KC group) and 10 healthy age-matched controls (non-KC group). Conjunctival swab samples were collected for standard microbiological culture. Microbial diversity, prevalence of opportunistic and commensal microorganisms, and age-related trends were assessed using Spearman correlation analysis.
Results. Patients with KC demonstrated ocular surface microbiota alterations characterized by increased prevalence of opportunistic bacteria (Pseudomonas aeruginosa 50%, Ralstonia pickettii 40%, Staphylococcus aureus – elevated) and reduced abundance of commensal flora (Staphylococcus epidermidis 20% vs 100% in controls; Corynebacterium spp. 20% vs 90% in controls). Spearman correlation revealed positive associations between age and Pseudomonas aeruginosa (ρ=0.86, p=0.006) and Staphylococcus aureus (ρ=0.62, p=0.027), and negative correlations with Staphylococcus epidermidis (ρ=−0.66, p=0.015) and Corynebacterium spp. (ρ=−0.60, p=0.025).
Conclusions. Pediatric patients with keratoconus exhibit distinct ocular surface microbial alterations that may be associated with ocular surface instability. The observed associations may serve as a basis for further research. However, the cross-sectional design and limited sample size do not allow causal inference or claims regarding microbiota profiling as a clinical biomarker without validation in larger prospective studies.
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