The role of infectious mediators and gut microbiome in the pathogenesis of celiac disease.

Celiac disease (CD) is an immune disorder that is associated with gluten sensitivity in people who are genetically predisposed. In celiac disease, food containing gluten mounts inflammatory response that results in villous atrophy in small bowel and increased permeability. This disorder is not only related to complications in the small bowel, but also has association with manifestations outside the GI tract. Small bowel mucosal immunity, exposed to infectious agents, is affected by CD; therefore, it is likely that patients with untreated celiac disease are more susceptible to infectious diseases. It is possible that sensitivity to gluten increases in patients infected with infectious diseases, and consequently infection may trigger CD in susceptible individuals. It is likely that, due to reduced immunity following the loss of intestinal villi, viral, bacterial, and parasitic infections develop faster in celiac disease patients and systemic complication occur more frequently. In addition, increased permeability, changing the microbiota following the chronic inflammation of the small intestine and abnormal immunological reactions are associated with celiac disease. PubMed, Medline, Google scholar, SID, and Magiran were searched for full text articles published between 1999 and 2014 in Persian and English. The associated keywords were used, and papers, which described particularly the impact of infectious agents on celiac disease, were selected. In this review, we have focused on the role of infectious agents and gut microbiota in the pathogenesis of celiac disease.