Human demodicidosis in Sfax area (Tunisia)

: Demodicidosis is an ectoparasitosis, common to humans and many mammals. It is caused by the proliferation of a mite Demodex sp in the pilosebaceous follicles. Its pathogenic role remains controversial. The aim of our study was to report epidemiological and clinical particularities of cases of demodicidosis diagnosed in our region. Over a period of nine years (January 2000 to December 2008), 427 cases of demodicidosis were diagnosed. 73.2% of cases were blepharitis and 26.8% of cases were facial dermatosis. The mean age was 44 years. Women were slightly more affected (56%) than men. Among 787 chronic blepharitis, 243 cases were due to Demodex sp (30.9%). They were treated with yellow oxide of mercury (Ophtergine® 1%). In the face, this mite has been isolated from erythematous and pruritic papulopustular lesions, and their distribution was as follows: cheeks (22.1%), forehead (13.4%), and nose (11.5%). The diagnosis was confirmed by parasitological examination of scales showing more than 5 Demodex sp/cm(2) and response to treatment with metronidazole (Flagyl®) for three months. Currently, there were a large number of arguments for the incrimination of Demodex sp in pathogenesis of dermatosis and blepharitis. Dermatologists and ophthalmologists must therefore think to this mite. The density of Demodex sp found by parasitological exam is a determining factor in establishing an anti-Demodex treatment whose effectiveness is a further argument for the diagnosis.