Abstract:

Objective To explore the application value of confocal laser scanning microscopy（CLSM） for detection of facial Demodex mites. Methods One hundred and twenty patients without basic diseases visiting the Department of Dermatology of the Third Xiangya Hospital for papules, pustules, erythema, and scales and suspected to have facial demodicosis were selected. Basic information and types of facial lesion were recorded. CLSM was performed to examine Demodex infection. Twenty patients with positive infection as indicated by CLSM were randomly selected for further verification with microscopy. Results Among the 120 patients, 59 were positive for facial demodicosis as indicated by CLSM, with a detection rate of 49.2%, 61.1% of males and 39.4% of females. The 20 patients with further microscopic examination were all diagnosed as Demodex folliculorum infection. Among the 120 patients, the Demodex detection rate showed a trend of increase with age, with the highest rate （72.7%, 16/22） in the group of 40-49 years［P<0.05 versus the 21.1% （4/19） in the group of 10-19 years and the 37.8% （14/37） in 20-29］. In addition, there was a significant difference in the percentage of patients with ＜5 mites and ≥5 mites in area of 4 mm×4 mm between type I （mainly erythema and scales）（80.6%, 29/36; 19.4%, 7/36, respectively; P<0.01） and type II lesions （mainly papules and pustules） （52.2%, 12/23; 47.8%, 11/23, respectively; P>0.05）（P<0.05）. Conclusion CLSM is an efficient technique for detecting facial Demodex, and is advantageous as it offers in-situ, noninvasive, painless, real-time and dynamic detection.

Key words: Confocal laser scanning microscopy, Demodicosis, Demodex folliculorum