Demodex folliculorum infestations in common facial dermatoses: acne vulgaris, rosacea, seborrheic dermatitis

Abstract Background: Demodex mites are found on the skin of many healthy individuals. Demodex mites in high densities are considered to play a pathogenic role. Objective: To investigate the association between Demodex infestation and the three most common facial dermatoses: acne vulgaris, rosacea and seborrheic dermatitis. Methods: This prospective, observational case-control study included 127 patients (43 with acne vulgaris, 43 with rosacea and 41 with seborrheic dermatitis) and 77 healthy controls. The presence of demodicosis was evaluated by standardized skin surface biopsy in both the patient and control groups. Results: In terms of gender and age, no significant difference was found between the patients and controls (p > 0.05). Demodex infestation rates were significantly higher in patients than in controls (p = 0.001). Demodex infestation rates were significantly higher in the rosacea group than acne vulgaris and seborrheic dermatitis groups and controls (p = 0.001; p = 0.024; p = 0.001, respectively). Demodex infestation was found to be significantly higher in the acne vulgaris and seborrheic dermatitis groups than in controls (p = 0.001 and p = 0.001, respectively). No difference was observed between the acne vulgaris and seborrheic dermatitis groups in terms of demodicosis (p = 0.294). Study limitations: Small sample size is a limitation of the study. The lack of an objective scoring system in the diagnosis of Demodex infestation is another limitation. Conclusion: The findings of the present study emphasize that acne vulgaris, rosacea and seborrheic dermatitis are significantly associated with Demodex infestation. Standardized skin surface biopsy is a practical tool in the determination of Demodex infestation.

Investigation of Demodex folliculorum frequency in patients with polycystic ovary syndrome

Abstract: Background: Background: Demodex mites are acari that reside in the pilosebaceous unit of the skin and have been associated with skin disorders. Objective: The objective of this study was to investigate the prevalence of Demodex folliculorum (D. folliculorum) mites in polycystic ovary syndrome patients as well as to examine the relationship between Demodex infestation and the presence of acne and oily or dry skin types in polycystic ovary syndrome patients. Methods: 41 polycystic ovary syndrome patients and 47 non-polycystic ovary syndrome control subjects were enrolled in the study. polycystic ovary syndrome was diagnosed according to the revised 2003 ESHRE/ASRM polycystic ovary syndrome Consensus Workshop Group diagnostic criteria. Microscopic examination of D. folliculorum mites was carried out by standardized skin surface biopsy. The result was considered positive when there were more than 5 mites per cm2. Results: D. folliculorum was positive in 53.7% of the polycystic ovary syndrome patients and 31.9% of the non-polycystic ovary syndrome group (p=0.052). Demodex positivity was significantly associated with acne (p=0.003) and oily skin (p=0.005) in the polycystic ovary syndrome patients but not in the controls. Study limitation: Our study is limited by the relatively small number of subjects and the observational nature of the study design. Conclusion: Demodex mites might have a role in acne pathogenesis in patients with polycystic ovary syndrome. Anti-Demodex treatment may increase the response to treatment of acne. Further studies are indicated.