Incidence of celiac disease autoimmunity and associations with maternal tuberculosis and pediatric Helicobacter pylori infections in 4-year-old Ethiopian children followed up in an HLA genotyped birth cohort

The epidemiology of Helicobacter pylori infection has changed with improvements in sanitation and methods of eradication. We performed a systematic review and meta-analysis to evaluate changes in the global prevalence of H pylori infection.

Celiac disease is a major public health problem worldwide. Although initially it was reported from countries with predominant Caucasian populations, it now has been reported from other parts of the world. The exact global prevalence of celiac disease is not known. We conducted a systematic review and meta-analysis to estimate the global prevalence of celiac disease.

The incidence of autoimmune diseases has been steadily rising. Concomitantly, the incidence of most infectious diseases has declined. This observation gave rise to the hygiene hypothesis, which postulates that a reduction in the frequency of infections contributes directly to the increase in the frequency of autoimmune and allergic diseases. This hypothesis is supported by robust epidemiological data, but the underlying mechanisms are unclear. Pathogens are known to be important, as autoimmune disease is prevented in various experimental models by infection with different bacteria, viruses and parasites. Gut commensal bacteria also play an important role: dysbiosis of the gut flora is observed in patients with autoimmune diseases, although the causal relationship with the occurrence of autoimmune diseases has not been established. Both pathogens and commensals act by stimulating immunoregulatory pathways. Here, I discuss the importance of innate immune receptors, in particular Toll-like receptors, in mediating the protective effect of pathogens and commensals on autoimmunity.