Association between Demodex and Severity of Meibomian Gland Dysfunction: A Case Study

Background: Dry eye disease is a prevalent condition affecting the ocular surface, leading to discomfort, inflammation and potential vision loss. Among its various causes, Meibomian Gland Dysfunction (MGD) and the presence of Demodex mites are notable contributors. Objective: This study aims to investigate the relationship between Demodex infestation and the severity of MGD. Methods: A total of 30 patients (60 eyes) treated at Thammasat Hospital were enrolled. Comprehensive eye examinations, including best-corrected visual acuity, slit-lamp biomicroscopy and meibomian gland assessment using the Keratograph 5 M, were performed. Eyelash samples were collected to detect Demodex presence under microscopy. Statistical analyses were conducted to explore correlations between Demodex detection, MGD severity, age and gender. Results: The mean age of participants was 59.83 ± 15.27 years. Demodex was detected in 21.7% of eyes, with a significant association found between age over 60 and Demodex presence (p = 0.028). No correlation was observed between Demodex detection and the severity of MGD, nor between Demodex presence and gender. Conclusions: This study indicates that while Demodex infestation is more prevalent in older patients, it does not correlate with the severity of meibomian gland dysfunction. Further research with larger sample sizes and advanced methodologies is warranted to better understand the interplay between Demodex and dry eye disease.