LAUSR

Background: Chronic Urticaria is a common disorder which is defined by recurrent occurrence of wheals and sometimes angioedema. It has a notable influence on the patients' quality of life. Regulation of the immune system is one of the important roles of the gut microbiota. The effect of dysbiosis considering some members of gut microbiota in patients with chronic urticaria has been demonstrated in our previous study. Objective: Comparing the frequency and bacterial load of Lactobacillus, Bifidobacterium, and Bacteroides between patients with chronic urticaria and healthy controls. Methods: 20 patients with chronic urticaria and 20 age and sex matched healthy individuals were included in the present study. Stool samples were analyzed for determining the frequency and bacterial load of Lactobacillus, Bifidobacterium, and Bacteroides genera. Results: There were no significant differences among the frequencies of detectable Lactobacillus, Bifidobacterium, or Bacteroides in stool samples of patients with chronic urticaria and healthy controls. The relative amounts of Lactobacillus and Bifidobacterium were significantly higher in fecal samples from controls compared to patients with chronic urticaria (P=0.038 and 0.039, respectively). Conclusion: It is the first study on the implication of Lactobacillus, Bifidobacterium, and Bacteroides genera as gut microbiota members in patients with chronic urticaria. HIGHLIGHTSDysbiosis may have a critical role in developing of chronic urticaria(CU).The load of Lactobacillus in stool of controls is higher than CU patients.The load of Bifidobacterium in stool of controls is higher than CU patients.A decrease in Bifidobacterium and Lactobacillus load may result in developing CU.