Demodex Infestation Found in 9 of 10 Eye Clinic Patients Using 2-Minute Technique

Demodex mites were found in the eyelashes of 94% of patients examined with a simple diagnostic technique at a standard ophthalmic practice, according to a study published online in the journal Clinical Ophthalmology.

“While infestations of Demodex are often easy to treat once identified, they often go undiagnosed since their symptoms are similar to other causes of eye irritation,” wrote corresponding author Fleur Goezinne, MD, PhD, of Eyescan Rijswijk in the Netherlands, and study coauthors. The study involved 173 patients recruited from a single outpatient ophthalmology clinic who, after a standard ophthalmic consultation, were examined for Demodex mites. Using an ophthalmic microscope, researchers looked for cylindrical dandruff and collarettes around the base of the eyelashes. Upon the removal of any cylindrical dandruff and collarettes found, researchers used tweezers to manipulate the eyelashes to reveal Demodex mites.

Among 106 patients included in the analysis, 94% had Demodex infestation. It took an average 2 minutes and 20 seconds to identify the first Demodex mite. Researchers identified an average three mites per hair shaft, according to the study.

The presence of Demodex mites significantly correlated with the presence of cylindrical dandruff, which was found in a total 92% of patients, the study showed. Collarettes were found in 58% of patients and blepharitis in 14% of patients.

“Our results suggest that Demodex mites are widespread in the eyelashes of eye clinic patients, and that eye doctors can use a simple and quick technique to diagnose Demodex infestation in their patients,” researchers wrote. “We propose that ophthalmologists and optometrists should consider using this diagnostic technique in patients with signs and symptoms of Demodex infestation.”

Reference

Boel C, Westerveld E, Kloos D, Goezinne F. Refining the diagnostic technique to determine prevalence of Demodex mites in eyelash hair follicles within standard ophthalmic practice: a single-center outpatient clinical study. Clin Ophthalmol. 2023;17:2027-2036. doi:10.2147/OPTH.S407898