Hirschsprung Disease

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Hirschsprung disease (hd) is a congenital disease involving the large intestine whereas there is inadequate motility of a part, or in rare cases (5%), all of the intestine. During the normal, development of the fetus, nerve cells known as ganglion cells migrate from the neural crest to the large intestine (colon). In hd, the migration is not complete resulting in the absence of these ganglion cell and inadequate motility of that part of the colon. The absence of ganglion cells results in a persistent over-stimulation of nerves in the affected portion of the colon, resulting in contraction and lack of (food propelling motion). In most cases of hd, the affected segment of the colon includes the distal colon and the rectum. This results in the inability of the rectum internal sphincter to relax. When the rectal sphincter can’t relax, stool cannot pass through to the outside of the body. This disorder is four times more common in males, than in females. The incidence is 1 in 5000 live births. This condition can be problematic in that it results in mechanical obstruction, constipation, vomiting, and a distended abdomen (stomach / intestine swelling), to name a few.

Clinical Manifestations

Newborn period: failure to pass meconium stool within 24-48 hours after birth, refusal to eat, bilious (green-colored) vomitus, and abdominal distention.

Infancy: failure to thrive, constipation, explosive, watery diarrhea and vomiting, fever, and ill in appearance.

Childhood: constipation, malnourished appearance, ribbon-like, foul smelling stools, a palpable, fecal mass, and visible persistalsis.

Diagnosis

In addition to the subjective findings, diagnosis is verified with the assistance of a barium enema and anus -rectum manometric (pressure measuring) exam. The diagnosis is ultimately confirmed by the finding of a rectal biopsy, which will reveal the absence of the ganglion cell.

Treatment

Most cases of hd will require surgical intervention in contrast to medical management with frequent enemas. Surgery consists of removing the portion of the intestine that lacks the ganglion cells. The procedure known as the soave endorectal pull-through consists of pulling the end of the normal colon through the muscular sleeve of the rectum and connecting them. This will relieve the obstruction, restore normal intestine motility and preserve the function of the external anal sphincter. If only a small portion of the intestine is involved a procedure known as an anal-rectal myomectomy may be performed. If the disease is not diagnosed early, a portion of the intestine may become enlarged due to the constipation and obstruction. If this is the case, the condition may have to be corrected in two stages with stage one involving a colostomyand the removal of the diseased portion of the colon. Stage two would involve reconnecting the two ends of the colon.

Prognosis

After the surgical procedure, some children may experience incontinence (loss of bowel control) and anal stricture (narrowing). Further treatment may include bowel retraining and anal dilatation therapy. Constipation may continue to be a problem and will require management by your pediatrician.