[Frequency of the appearance of Demodex sp. in various patient and age groups].

Demodex folliculorum and Demodex brevis are acari that can be found in hair follicles and sebaceous glands of the skin, especially on face of humans. In this study, Demodex sp was investigated in regard to allergic diseases, age and gender. A total of 197 patients (117 with rosacea, 29 with akne vulgaris, and 51 with allergic diseases) were examined using the standardized skin surface biopsy (SSSB) and 97 out of 197 (49.23%) cases were found to be positive by the Inonu University Medical Faculty Department of Parasitology. There was no significant difference between mite positivity and negativity between the genders, while a higher rate of Demodex sp. was found in patients with rosacea and a lower rate in patients under 20 years old (p0,005). As a result, patients over 20 years old, especially those with rosacea, must be investigated for Demodex sp.