Demodex folliculorum Infestation in Meibomian Gland Dysfunction Related Dry Eye Patients

Yiran Hao; Xiaoyu Zhang; Jiayu Bao; Lei Tian; Ying Jie

doi:10.3389/fmed.2022.833778

Demodex folliculorum Infestation in Meibomian Gland Dysfunction Related Dry Eye Patients

Front Med (Lausanne). 2022 Feb 24:9:833778. doi: 10.3389/fmed.2022.833778. eCollection 2022.

Authors

Yiran Hao^{1

2}, Xiaoyu Zhang^{1

2}, Jiayu Bao^{1

2}, Lei Tian^{1

2

3}, Ying Jie^{1

2}

Affiliations

¹ Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
² Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
³ Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University & Capital Medical University, Beijing, China.

Abstract

Objective: To report the influence of Demodex folliculorum (D. folliculorum) infestation in patients with meibomian gland dysfunction (MGD) related dry eye and the associations of the infestation with MGD related dry eye.

Methods: Eyelashes (three from the upper eyelid and three from the lower eyelid) from 119 eyes of 119 patients diagnosed with MGD related dry eye were examined under a light microscope. There were 68 eyes of 68 patients with MGD related dry eye and D. folliculorum infestation (Demodex positive group) and 51 eyes of 51 patients without infestation (Demodex negative group). All patients completed an Ocular Surface Disease Index (OSDI) questionnaire and underwent tests for dry eye and MGD. The tests included fluorescein tear breakup time (TBUT), corneal fluorescein staining, Schirmer I test (SIT), lid margin abnormalities, meibum expression assessment, and meibomian gland dropout.

Results: The scores for OSDI, corneal fluorescein staining, lid margin abnormalities, meibum expression, and meibomian gland dropout were significantly higher (all P < 0.05), while TBUT was significantly shorter in the Demodex positive group compared to the Demodex negative group (P = 0.020). The SIT values did not significantly differ between groups. Chalazion was significantly more prevalent in the Demodex positive group. The number of D. folliculorum was positively correlated with all three MGD parameters (P ≤ 0.035), OSDI; corneal fluorescein scores, and it was inversely correlated with BUT. The correlation for SIT was R ² = 0.075 (P = 0.064).

Conclusion: Demodex folliculorum infestation is possibly one of the key contributors in the pathogenesis of MGD related dry eye, and a higher prevalence of chalazion was found in D. folliculorum infected patients. The possible causal role of D. folliculorum infestation needs to be further studied.

Keywords: Demodex folliculorum infestation; chalazion; dry eye; lid margin abnormality score; meibomian gland dropout; meibomian gland dysfunction; meibum expression.