Gastro: Hirschsprung's Disease Flashcards
What is Hirschsprung’s Disease?
is a form of megacolon that occurs when part or all of the large intestine or parts of the gastrointestinal tract have no ganglion cells and cannot function.
What ends up happening?
Enlarged colon with collapse rectum and no innervation of large intestine.
Swollen area can lead to Perforation.
? That effected area cannot relax and pass stool through the colon.
vomiting, explosive stools, abb swollen, lots of gas and bloody diarrhea.
What cause’s the disease?
During normal prenatal development, cells from the neural crest migrate into the large intestine (colon) to form the networks of nerves called the myenteric plexus (Auerbach plexus) (between the smooth muscle layers of the gastrointestinal tract wall) and the submucosal plexus (Meissner plexus) (within the submucosa of the gastrointestinal tract wall).
But now this does not happen and nerves are incomplete to regulate the activity of the colon.
This is considered congenital (birth defect)
Where does the constriction occur?
75% with history of this disease will be in the siegmoid colon, rectum. In effect have no good peristalsis. That part is collapsed and restricted, stretched to make TOXIC mega colon. When we have thin stretched walls, we will have Damage by stretching intestine.
8% have entire colon effected.
Enlarged section is found proximally while narrowed anganglionic section is found distally
what is the most severe symptom in children?
How prevalent is the disease?
Constipation
1 out of 5000 live births, More boys than girls, 10% is familial.
How do we diagnose?
We take Incisional Biopsy to see damage, before surgery. From collapse part, the border, and up the plenic sphincter. We will remove damage area from good intestine. If worse, will remove whole intestine and use pouch from small intestine.
Definitive diagnosis is made by suction biopsy (gold standard of diagnosis) of the distally narrowed segment. also anorectal manometry
What is the norm for infant defecation?
90% of babies pass their first meconium within 24 hrs and 99% within 48 hours.
What are early signs?
typically diagnosed shortly after birth, it may develop in adulthood because of presence of megacolon. Baby fails to pass the first stool (meconium) within 48 hours of dilvery. Some cases are diagnosed later, into childhood. Fecal retention.
Aganglionosis is the abscene of ganglin nerve cells mainly her ein the intestinal tract. What happens because of this abscence?
cells results in persistent over stimulation of nerves in affected area.
Duhamel-ikeda procedure
uses a surgical stapler to connect the good and bad bowel.
Describe the process of Reversible Colostomy
The first stage of treatment used to be a reversible colostomy. In this approach, the healthy end of the large intestine is cut and attached to an opening created on the front of the abdomen. The contents of the bowel are discharged through the hole in the abdomen and into a bag. Later, when the patient’s weight, age, and condition are right, the “new” functional end of the bowel is connected with the anus.
