Clinical Significance Of The Predominant Bacterial Strains And Demodex On Rosacea

Objective: To understand the relationship between demodex and bacteria infection in rosacea;investgate bacteria flora in the lesions of the patients with rosacea and antibiotic resistance of bacteria from patients with rosacea.Methods: The skin samples from the lesion and the neighboring regions in 60 rosacea patients were collected for assay.The skin samples was used to detect demodex on the nasal part and frontal region; sebum and tissue on face was scraped and cultured to examine bacteria .The comparative study was also made by matching the 60 skin samples from normal controls. The data were analysed by statistics.Results: It was found that 48(80 %)of 60 cases with rosacea were infected by demodex , the positive rate was higher when compared with the normal controls.The isolation rate of bacteria in rosacea group was higher than that normal .the most common bacteria isolated was Gram - positive bacteria, including staphylococcus Epidermidis. S.sarophyticus and S. Aureus . the most common anaerobe isolated was propionibacterium. Generally,they were in the state of the sub-clinical inefetion. The clinical inefetion usually happened when the human body resistance for baeteria was decreased.the human body resistance for baeteria may decreased when demodex infection was found in rosacea .In all of the bacterium, the resistant rate to Roxithromycin and Metronidazole was 39.2 % and 99.6%.The rate to Chloromycetin was the lowest(28.9%).Conclusion :Demodex and bacteria infection in rosacea are important facor inducing rosacea.The bacteria not often detected in the face were not also discovered,and a positive correlation was not observed between the demodex and bacteria infection (P > 0.05).The most sensitive antibiotics for the baeteria of rosacea is Chloromycetin.