Extragastric infection of Helicobacter pylori and alopecia areata: a systematic review and meta-analysis

Alopecia areata is an autoimmune cutaneous disease, and the involved mechanism in its pathogenesis has not yet been properly identified. Based on the available evidences, the prevalence of alopecia areata is more common than other autoimmune disorders that caused by Helicobacter pylori infection such as autoimmune thyroiditis, psoriasis, celiac, and Sjogren's syndrome. In addition, previous published reports have shown that antibiotic therapy can cure alopecia areata. Hence, it seems that there is a probable relationship between infection with H. pylori and alopecia areata. In general, the main purpose of this study was to statistically evaluate the infection with this bacterium and its progression to alopecia areata. Because, the available documents had controversial results, we evaluated the data from 926 cases to investigate the relationship between infection with H. pylori and alopecia areata. According to our statistical analysis, we found that the incidence of H. pylori infection among alopecia areata cases is high, also our findings revealed that there is significant association between H. pylori infection and susceptibility to alopecia areata (odds ratio: 1.57; 1.19–2.05 with 95% confidence intervals). Based on the current results, H. pylori infection can be considered as a risk factor for alopecia areata development.