Acquired internal inter-intestinal fistulas in children are rare. Their cause may be acute intestinal perforation after surgery, or covered (not diagnosed) ulcer as a complication of NEC in deeply premature children. Of the 3 children with acquired internal inter-intestinal fistulas, 2 were operated on for congenital intestinal obstruction. After the operation, acute intestinal ulcers appeared. In a premature child, an inter-intestinal fistula arose against the background of NEC, which was treated conservatively. All the children were operated on, the inter-intestinal fistula was eliminated. 2 children are alive, 1 died after surgery (multiple organ failure).

Purpose - to determine the possibility of laboratory and endoscopic methods for the diagnosis of ischemic bowel disorders in children with ASIO. Material and methods. 40 children with ASIO underwent routine examinations, including ultrasound, abdominal x-rays, laparoscopy, and lactate (lactic acid). Results. It has been established that the lactate level and laparoscopic examination make it possible to diagnose ischemia with an accuracy in children with ASIO. Conclusion. Lactate levels and laparoscopy in children with ASIO are important factors in the diagnosis of intestinal ischemia.