The effect of sebum configuration to the density of demodex in patients with diabetes mellitus

Aim: Demodex spp. are ectoparasites living in pilosebaceous unites in humans that increase with age. They feed with host sebum. Demodex spp. effect commensal, mutual or parasitic according to the host immune status. Skin diseases that Demodex spp. cause are known as demodicosis or demodicidosis. Diabetes mellitus (DM) is a metabolic disorder which has various types and increasing incidence in the community. Skin symptoms, especially infections are frequent in diabetes mellitus. Immunity disorders are also occur in diabetes mellitus. Skin is a large organ that has important functions in human body. Its protective barier consists of sebum secretion, moisture and acid manto. In this study, we aimed to determine the density of Demodex spp. in patients with diabetes mellitus and the effects of skin sebum, moisture, pH levels and sebum configuration on this density.Material and Method: A total of 48 patients with DM as study group were included in the study. As first control group, 45 patients who have not DM but have demodicosis with Demodex spp./cm2 ?5 and as second control group, 40 individuals who have not DM and demodicosis were included in the study. The group of DM was seperated into two groups as Demodex spp.?5 and Demodex spp.<5 according to the density of Demodex spp./cm2. All the groups were questioned about age, sex, additional disease, smoking, alcohol usage and the type and duration of DM. Waist circumference, body fat percentage, fasting glucose, triglyceride, total cholesterol, HDL cholesterol, LDL cholesterol, VLDL cholesterol, HbA1c and C-peptide levels were recorded. The skin sebum, moisture and pH levels were measured in all the patient and control groups. Demodex spp. density was determined with standardized skin surface biopsy method. The sebum samples were taken from the forehead and HPTLC method was performed to these samples and then dansitometric analyses were applied to the HPTLC plates.Results: Demodex spp. were detected in 29% of DM patients. Demodex spp. were found especially on the cheeks. The skin sebum and moisture levels were low in all groups and there was no statistically significant difference between the groups (p>0.05). The skin pH levels were determined higher in demodicidosis group and this result was statistically significant (p<0.05). Cholesterol ester was significantly higher in demodicosis group as a result of sebum configuration (p<0.05).Conclusion: We found that Demodex spp. located on cheeks anymore and lived in more alkali environment. The density of Demodex spp. in DM was higher in comparison with many studies in the literature. But we think that further studies with larger groups are needed on this issue. Because of the increased cholesterol ester levels in demodicosis group on sebum confıguration, we consider that Demodex spp. consume cholesterol ester as a nourishment in sebum or, in another word, cholesterol ester may be a suitable growth medium for the proliferation of Demodex spp.