What is Hirschsprung's disease?
Hirschsprung's
disease (HD) is a disease of the large intestine (colon). It
usually occurs in children and results in a blockage of the
intestine so that stool cannot pass through. Some children with HD
can't have bowel movements at all, and the stool creates a blockage
in the intestine. If HD is not treated, stool can fill up the large
intestine, causing serious problems such as infection, bursting of
the colon, and even death. HD occurs five times more often in boys
than it does in girls. HD occurs in 1 out of every 5,000 births. It
is sometimes associated with inherited diseases such as
Down's syndrome.
How does HD cause constipation?
Normally, muscles
in the large intestine push stool to the anus, where stool leaves
the body. The intestine's ability to push is enabled by nerve
cells in the intestine called ganglion cells. A person with HD does
not have these nerve cells in part of the large intestine, creating
the problems associated with the disease. Sometimes these nerve
cells are missing from only a few centimeters but they can also be
missing from long segments of the large intestine.
For people with HD, the healthy muscles of the intestine push
the stool until it reaches the part of the intestine without the
nerve cells. At this point, the stool stops moving. New stool then
begins to collect behind it.
Sometimes the ganglion cells are missing throughout the whole
large intestine and even parts of the small intestine. When the
diseased section of the intestine reaches or includes the small
intestine, it is called long-segment disease. When the diseased
section includes only part of the large intestine, it is called
short-segment disease.
What causes HD?
HD develops before a child is born.
Normally, nerve cells grow in the baby's intestine soon after the
baby begins to develop in the womb. These nerve cells grow down
from the top of the intestine all the way to the anus. With HD, the
nerve cells stop growing before they reach the end.
It is unclear why the nerve cells stop growing; however, there
is no evidence that it is caused by the mother's actions or
activities while she is pregnant.
What are the symptoms of HD?
Symptoms of HD usually
show up in very young children. Sometimes, however, they don't
appear until the teenage years or adult life. The most common
symptoms include:
- Failure to pass meconium (contents of the fetal intestine)
shortly after birth
- Failure to pass first stool within 24 to 48 hours after
birth
- Constipation
- Abdominal swelling
- Vomiting
- Watery diarrhea (in newborns)
- Poor weight gain
- Slow growth (in children under 5 years)
- Malabsorption