Prevalence of Demodex Folliculorum and Demodex Brevis in Patients with Blepharitis and Chalazion

Abstract

Purpose: Demodex folliculorum and Demodex brevis are common ectoparasites on skin that also can lead to blepharitis and chalazion. The aim of our study is to determine the prevalence of Demodex spp. in eyelashes of patients diagnosed with chronic blepharitis and chalazion. Methods: This study included 330 patients diagnosed with chronic blepharitis, 70 patients diagnosed with chalazion and 130 volunteers without any ocular problems. Patient eyelashes were examined under a light microscope at magnifications of × 40, × 100 and × 400. Demodex spp. were determined. Results: Parasite prevalence was significantly higher in blepharitis (75.5%) and chalazion groups (70%) compared to the control group (16.2%) (p <0.001). The prevalence of D. folliculorum in the blepharitis group and D. brevis in the chalazion group was found to be significantly higher compared to other groups (p <0.05). The average number of mites per eyelash was found to be significantly higher in patients with Demodex positive blepharitis (p = 0.001) and in chalazion patients (p = 0.047) than in the control group. It has been determined that mite positivity increases with age in blepharitis and control groups (p <0.05). In the group with blepharitis, it was found that mite positivity was significant in the presence of symptoms (p = 0.0001) and Demodex positivity decreased as the education level of individuals increased (p = 0.039). Conclusion: The results of the study show that Demodex acari infestations should be considered in chronic blepharitis and chalazion.

Eyelid Exfoliation Treatment Efficacy and Safety in Dry Eye Disease, Blepharitis, and Contact Lens Discomfort Patients: A Systematic Review

“…9,10 In addition, the presence of Demodex folliculorum mites on the eyelid margin is another known pathogenic risk factor for blepharitis. 11,12 A recent study by Akkucuk et al 13 reported that 75.5% of patients with blepharitis had Demodex folliculorum, which may be identified clinically by the pathognomonic sign of collarettes at the eyelash base. 14,15 As blepharitis progresses, meibomian gland dropout and cicatricial eyelid changes can occur.…”