Conjunctival Flora in Patients with Parkinson's Disease

Abstract

Purpose: To identify the conjunctival flora in patients with Parkinson's disease (PD) and compare it with the conjunctival flora of healthy subjects. Methods: One hundred six eyes of 106 patients with PD and 102 eyes of 102 age-matched healthy subjects were included in the study. All subjects had a detailed anterior segment examination, including eye blink rate and conjunctival cultures. Conjunctival cultures were taken with a sterile cotton-tipped dry swab without topical anesthesia. The culture samples were inoculated onto 5% sheep blood agar and chocolate agar, as well as brain heart infusion broth. The bacterial growth was evaluated in a quantitative manner as colony-forming units (CFU). All bacterial isolates were identified, and statistical analyses were performed by chi-square test to determine if there were differences in flora between PD and control groups. Results: Eighty-six (81.1%) of the 106 eyes in patients with PD and 73 (71.5%) of the 102 eyes in control group were found to have positive conjunctival cultures (p = 0.144). Coagulase-negative Staphylococcus was the most commonly isolated bacterial species in both groups, found in 45 (42.4%) and 49 (48%) of eyes in patients with PD and control group, respectively (p = 0.503). Among all bacterial isolates, only Staphylococcus aureus was found to be statistically different between the two groups, noted in 32 (30.1%) and 10 (9.8%) of eyes in patients with PD and control group, respectively (p = 0.001). Conclusions: Coagulase-negative Staphylococcus, Staphylococcus aureus, and Corynebacterium species were the most commonly isolated bacterial species in the PD group. Among all bacterial isolates, only Staphylococcus aureus was significantly higher in the conjunctival flora of patients with PD than in those in the control group.

Keywords:

• coagulase-negative Staphylococcus
• conjunctival flora
• eye blink rate
• Parkinson's disease
• Staphylococcus aureus