Background: Chronic inflammatory diseases are the long-term response of the organism to any stimulus. Crohn's (CD) and Celiac (CeD) diseases are among chronic inflammatory diseases, and both cause chronic inflammation in the intestines. Both diseases are caused by polygenic, environmental, and lifestyle risk factors. Inflammation can perpetuate disease and cause it to become chronic. For this reason, CD and CeD that choose the intestine as the target organ may trigger each other. Although the relationship between these diseases is widely mentioned in the literature, scanty knowledge and research have been done on the immune mechanisms of these inflammatory diseases.