**Incomplete intestinal fistula** (non-occlusive fistula, incomplete, imperfect, marjoram) is a disease characterized by the release of intestinal contents onto the skin or mucous membranes through defects in the intestinal wall. The general name for this pathology is fistula (false), fistula. Incomplete intestinal fistulas – 25% of cases of all intestinal fistulas. A fistulous tract (intestine, mucous membrane, skin) is formed either along the course of an ulcer of the small intestine (most often the rectum), or at the point of bending, turning of the small intestine, or in the ileocecal section of the intestine (rarely). Possible in case of disturbances in the formation of the fetal body, after cystic intestinal dysontogenesis of congenital origin (megaintestine, megasigma), as well as in patients with malnutrition or massive postpartum intestinal paresis. A common cause of intestinal fistula formation is helminthic invasion of the small intestine, anaerobic