RESUMO
Background: Demodex mites can lead to various skin disorders, from non-specific dermatitis to conditions that mimic other diseases, making it challenging to diagnose accurately. Additionally, it has been reported that Demodex mites can cause skin conditions such as perioral dermatitis, pustular folliculitis, pityriasis folliculorum, blepharitis, and rosacea. Due to conflicting studies, there is a debate regarding the link between Demodex mites and acne vulgaris. This study aims to determine the prevalence of Demodex mites on the faces of individuals with acne vulgaris, acne with nonspecific facial dermatitis, and healthy facial skin to clarify the association. Materials and Methods: This observational case-control study involved 120 participants aged 18-37: 40 individuals with acne vulgaris only, 40 with acne and nonspecific facial dermatitis, and 40 healthy controls. The same dermatologist examined and diagnosed all participants to ensure accuracy before being grouped. The Standardized Skin Surface Biopsy (SSSB) method was used to detect Demodex mites in all three study groups. Furthermore, additional samples were collected randomly from acne lesions using the Superficial Needle Scraping (SNS) method in the two acne groups. Results: The study found no significant difference in Demodex prevalence and high Demodex density rate between patients with only acne vulgaris and the control group (p>0.05). However, acne patients with nonspecific facial dermatitis had a higher rate of Demodex prevalence and high Demodex density rate than the only acne vulgaris and control group (p<0.05). The clinical symptoms of nonspecific facial dermatitis in acne patients strongly associated with Demodex mites are patchy red, dry, scaly skin, roughness, insect bite-like papules, and flushing. Conclusion: Demodex prevalence and high Demodex density rate are not associated with acne vulgaris. Still, it is associated with acne and nonspecific facial dermatitis, particularly in patients with patchy redness, dry, scaly skin, roughness, insect bite-like papules, and flushing.