Hirschsprung's Disease
Also known as . . . Hirschsprung disease, megacolon, congenital megacolon
What is it?
During normal embryonic development, nerves cells develop in the layers of the
intestinal tract. The nerve cells begin their development in the upper part of the
intestinal tract nearest the mouth and migrate all the way to the lower part if the
intestinal tract near the anus. Hirschsprung’s disease occurs when the specialized
nerve cells, called ganglion cells, fail to complete their normal migration for the entire
length of the bowel during fetal development. In Hirschsprung’s disease, normal nerve
cells are not found in the rectum and for variable lengths of intestine above the rectum.
The affected intestine lacks the normal nerve signals to allow it to relax and move
intestinal contents through it. The consequence of the abnormal innervation is abnormal
intestinal function that ranges from complete intestinal obstruction to problems with
constipation. Hirschsprung’s disease can impair growth and development, and in some
cases, lead to life-threatening intestinal infection.
Diagnosis and treatment
In an infant, failure to pass a bowel movement (meconium) within the first 48
hours of life first suggests Hirschsprung’s disease. Cases diagnosed later in life
usually present with severe constipation. If Hirschsprung’s disease is suspected,
tests are used to confirm the diagnosis. A barium enema may be performed. In
Hirschsprung’s disease, a "transition zone" is seen where the normal bowel
meets the bowel with abnormal nerve cells. Another test, performed in older patients, is
anorectal manometry. This test measures the ability of the anal sphincter muscles to relax
properly, which does not occur in Hirschsprung’s disease. The barium enema and
manometry tests may not be conclusive. The best test for the diagnosis of
Hirschsprung’s disease is a biopsy of the rectal lining. This procedure can be
performed at the bedside or in the office in infants. The procedure involves taking
several small pieces of the rectal lining to be examined for the presence or absence of
ganglion cells. The absence of ganglion cells in these specimens confirms the diagnosis of
Hirschsprung’s disease.
Patients diagnosed with Hirschsprung’s disease require an
operation. The abnormal portion of the bowel (usually rectum and lower colon) is removed
and intestine with normal nerve cells is brought down and attached just above the anus.
Using an incision in the abdomen, or more recently, minimally invasive/laparoscopic
techniques, the surgeon will mobilize the large intestine from the point at which normal
nerve cells are present so that it can be brought to the level of the anus. Then, working
just inside the anus, the surgeon removes the abnormal bowel and brings down the normal
bowel in place of the old. The operations for Hirschsprung’s disease are referred to
as "Pull-through procedures," because the normal intestine is "pulled
through" the pelvis. The operation requires 1-3 days in the hospital. Usually, the
operation can be completed in one stage with no need for a colostomy. In some cases, such
as an extremely long segment of abnormal bowel or if serious infection is present, a
temporary colostomy may be created, which is reversed at a later operation.
Glossary of Terms
Ganglion cells: the specialized nerve cells responsible for the relaxation of the
bowel musculature; the absence of these cells on biopsy diagnoses Hirschsprung’s
disease
Suction rectal biopsy: the procedure performed on infants with
suspected Hirschsprung’s disease; a small biopsy probe is introduced into the
patient’s rectum, allowing removal of a small piece of the rectal lining
Enterocolitis: the most feared complication of Hirschsprung’s
disease; this intestinal infection, can occur either prior to or after correction of the
condition; symptoms include abdominal distention, explosive, foul-smelling diarrhea, and
lethargy; left untreated, the condition can rapidly progress to overwhelming infection and
death
Colostomy: a procedure in which the colon is brought out onto the skin
of the abdomen, such that bowel contents are collected in a pouch or bag, instead of
passing through the anus
Meconium: the first bowel movement passed by a newborn infant; usually
occurring within the first forty-eight hours after birth.
Physician's Who Treat Hirschsprung's Disease
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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