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.

Abstract Background: Psoriasis is a chronic immune-mediated inflammatory skin disease that is associated with cardiovascular comorbidities. Objectives: The objective of this retrospective study is to assess the C-reactive protein, monocyte-to-high-density-lipoprotein ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio as inflammatory markers in patients with psoriasis and to search for a relationship between these parameters and psoriasis severity, as defined by the psoriasis area and severity index. Methods: There were 94 patients with psoriasis and 118 healthy controls enrolled in the study. The C-reactive protein, monocyte-to-high-density-lipoprotein ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio values of two groups were retrospectively evaluated. Results: Statistically significant differences were observed in terms of C-reactive protein, monocyte-to-high-density-lipoprotein ratio, neutrophil-to-lymphocyte ratio and monocyte-to-lymphocyte ratio between the patient and control groups (p = 0.001, p = 0.003, p = 0.038, and p = 0.007, respectively). Positive correlations were found between the psoriasis area and severity index and the values of C-reactive protein, monocyte-to-high-density-lipoprotein ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio (r: 0.381; p < 0.01, r: 0.203; p < 0.05, r: 0.268; p < 0.01, r: 0.374; p < 0.01, r: 0.294; p < 0.01, respectively). Study limitations: The small sample size and the retrospective design of the study are limitations. Conclusion: Elevated C-reactive protein, monocyte-to-high-density-lipoprotein ratio, neutrophil-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio were significantly associated with psoriasis. A positive correlation between C-reactive protein and monocyte-to-high-density-lipoprotein ratio leads to the suggestion that monocyte-to-high-density-lipoprotein ratio might be a reliable parameter in psoriasis during the follow-up. The relationship between the diasease and inflammatory parameters might provide early detection of cardiovascular morbidities in psoriasis patients.