- Flashcards
What are the developmental anomalies related to the intestines?
Atresia, Stenosis, Duplication of Bowel, Omphalocele, Gastroschisis, Malrotation, Meckel’s diverticulum
These are congenital defects affecting the structure and function of the intestines.
Define atresia in the context of intestinal disorders.
The complete failure of development of the intestinal lumen
Atresia can occur in any segment of the intestine.
What is stenosis?
Narrowing of the intestinal lumen with incomplete obstruction
It may affect any segment of the intestine.
What is Meckel’s diverticulum?
A blind tubular pouch present in 2% of the population resulting from failure of involution of the proximal vitelline duct
It is usually located in the distal ileum and may contain gastric or colonic mucosa.
What are the symptoms of Meckel’s diverticulum?
Generally asymptomatic, but may lead to intestinal bleeding or symptoms resembling acute appendicitis
Bacterial overgrowth may lead to vitamin B deficiency.
What is Hirschsprung disease?
A birth defect where some nerve cells are missing in the large intestine, causing problems with passing stool
It occurs in 1 in 5000 to 8000 live births and is more frequent in males.
What genetic mutations are associated with Hirschsprung disease?
Inactivating mutations in RET genes and RET ligands
50% of familial cases are linked to these mutations.
What happens in the aganglionic segment of Hirschsprung disease?
It lacks both the Meissner and Auerbach myenteric plexuses
This causes functional obstruction and progressive distention of the proximal colon.
What are the complications of Hirschsprung disease?
Superimposed enterocolitis, fluid and electrolyte disturbances, perforation of the distended colon
These complications can be serious and require prompt medical attention.
What is acquired megacolon?
A condition characterized by the abnormal dilation and lengthening of the colon in the absence of an organic disease
It can occur due to various factors including Chagas disease and toxic megacolon.
What causes acquired megacolon?
Chagas disease, organic obstruction by a neoplasm or inflammatory stricture, toxic megacolon complicating ulcerative colitis
It is often a functional psychosomatic disorder.
What is the usual location of Meckel’s diverticulum?
In the distal ileum, 80 cm proximal to the ileocecal valve
It is always located on the antimesenteric border.
True or False: Malrotation is caused by improper embryologic rotation of the gut.
True
It increases the risk for twisting off the blood supply to the intestine.
Fill in the blank: The condition where abdominal musculature fails to form, leading to herniation of abdominal contents is called _______.
Omphalocele
This results in the formation of a ventral membranous sac.
What is the primary effect of Hirschsprung disease on the colon?
Functional obstruction and progressive distention of the proximal colon
The affected segment is usually not distended.
