Abstract
Purpose :
Demodex is a vector for bacteria and the prevalence of bacteria on eyelids has shown to be correlated with Demodex presence. To understand type(s) and/or number of bacteria in those with Demodex blepharitis, the Pandora study evaluated the bacterial flora on the eyelid margin and conjunctival fornices in Demodex blepharitis (DB) and normal or non-Demodex blepharitis (non-DB) patients.
Methods :
This is a prospective, observational, multicenter study. Swabs were taken from the eyelid margin and conjunctival fornices of 24 patients with at least 10 collarettes (DB) and 11 patients who have no diagnosis of DB or other forms of blepharitis (patients without collarettes, or signs or symptoms consistent with blepharitis). By study completion, samples from a total of 60 DB patients and at least 40 non-DB patients will be collected. All eyelid/conjunctival swabs were sent for culture on blood, Chocolate and Sabouraud agar plates and gram stain.
Results :
Methicillin-resistant Staphylococcus epidermidis (MRSE) were isolated from 29% (7/24) of DB patients while only 2 out of 11 patients (18%) had MRSE in the non-DB group. More than one type of bacteria was found in 63% and 45% of the DB and non-DB patients, respectively. Staphylococcus epidermidis was the most isolated bacteria in both DB and non-DB eyelids but methicillin-sensitive coagulase negative Staphylococcus epidermidis was more commonly isolated in non-DB patients (45% vs 21%).
Conclusions :
These preliminary results suggest that more pathogenic (MRSE) and more bacterial strains are found in DB patients compared to normal patients. This signifies the importance of treating Demodex blepharitis to minimize the presence of pathogenic bacteria which can compromise outcomes in patients wearing contact lenses or undergoing refractive or cataract surgery. Larger sample size upon study completion will confirm these preliminary findings.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.