Demodex spp. prevalence among senile cataract cases undergoing surgery.

Abstract

Purpose : It is unclear whether Demodex spp. infestation and blepharitis could lead to surgical complications in cataract cases undergoing surgery. Demodicosis is age-dependent and a prevalent comorbid condition among this population. However, there are conflicting reports regarding its prevalence, ranging from 51% – 95%. Here, we estimated the prevalence of Demodex spp. among patients undergoing cataract surgery and its association with postoperative complications.

Methods : We performed a cross-sectional study of 150 senile cataract cases undergoing surgery from an ophthalmology center in Mexico City. For our exposure of interest (Demodex spp. infestation), we performed eyelash epilation (eight in total per patient) and immediately instilled 20 µL of 10% potassium hydroxide. We diagnosed demodicosis by direct microscopic examination. Additionally, we estimated the infestation index by taking the ratio of the absolute count of Demodex spp. for each sampled eyelash.

Results : We assessed 150 patients. Our population was aged (~68 ± 12.3 years), and men and women were equally distributed. The crude prevalence of Demodex spp. is 67.3% (95% CI 58.5 - 74.0). There was no significant change in demodicosis proportion between males and females. There was a significant marginal linear change in BMI but was lost when stratifying by WHO categories. The proportion of postoperative complications was not significantly different between Demodex spp. infested and not infested cases.

Conclusions : The prevalence of Demodex spp. in our population is 67.3%. Our results suggest BMI might influence demodicosis prevalence similar to age. Further studies, particularly among Hispanic are warranted.

This is a 2020 ARVO Annual Meeting abstract.