Browse the corpus
Walk the Even Hospital Database by book and chapter — the raw source passages that ground Ask, DDx, and the rest.
2 passages
The bowel, which is composed of the small and large intestines, is vital to life as it absorbs nutrients necessary for all body functions. It is essential to understand the embryology of the bowel as errors in development serve as the basis for many congenital diseases. The gastrointestinal tract divides into the foregut, midgut, and hindgut. The foregut forms the esophagus, stomach, pancreas, and the duodenum up to the ampulla of Vater. The midgut forms the distal duodenum, jejunum, ileum, cecum, ascending colon, and proximal two-thirds of the transverse colon. Finally, the hindgut forms the distal one-third of the transverse colon, descending colon, sigmoid colon, and the rectum.[1] This article will focus on the development of the midgut and hindgut and explore developmental abnormalities that may occur during this process.
The complexity of bowel formation allows for many areas in which there can be errors in development. These errors manifest as the following diseases[11][12][9][13]: Malrotation - the midgut does not undergo proper rotation which predisposes to midgut volvulus. Volvulus - bowel twists around its mesentery, causing bowel obstruction. Persistent Vitelline Duct - the vitelline duct connection to the umbilicus remains patent resulting in enteric drainage. Meckel Diverticulum - this condition is a remnant of the vitelline duct attached by a fibrous stalk to the umbilicus, which can cause bowel obstruction or bleeding if ectopic gastric tissue is present in the diverticulum. Omphalocele - This represents a failure of the herniated midgut to return to the abdominal cavity. Hirschsprung Disease - this is the failure of neural crest cell migration, which impairs relaxation of the bowel, creating an obstruction. Imperforate Anus - the cloaca fails to perforate, and thus the rectum leads into a blind pouch. Intestinal Atresia - discontinuous bowel thought to be due to disruptions in a segment of bowel blood flow Gastrointestinal duplications are very rare pathologies, with a response in the population of 4 to 18% regarding the colon. It is not always readily identifiable in the pediatric period, with symptoms such as colic and constipation.