Definition
Hirschsprung’s disease is a rare congenital disease. It occurs with a frequency of about 1 : 3. 000 – 5.
000 affected newborns. The disease manifests itself in the gastrointestinal tract. In one part of the intestine, nerve cells and nerve cell bundles (ganglia) are missing.
This is known as aganglionosis. In addition to the intestine, the inner sphincter muscle, which is responsible for stool continence, is also affected by the lack of nerve cells. Due to the lack of nerve cells in bowel segments, the stool can no longer be transported towards the anus by undulating muscle movements (peristalsis), so that the intestinal contents stool accumulates in front of the diseased bowel segment, because the muscles of the affected area can no longer relax, resulting in a narrowing.
Hirschsprung’s disease usually only affects the large intestine, only very rarely can the small intestine also be affected. In about three quarters of cases, the sigmoid colon and rectum are affected, i.e. the two end sections of the colon. In less than ten percent of patients, the entire colon is affected.
The symptoms are more pronounced in these patients. The disease occurs in newborns or infants. Only in very few cases can it also manifest itself in adulthood. This is usually the case when the affected nerve-free section of the intestine is only very short and therefore of little importance.
Causes
Hirschsprung’s disease is caused by a disturbed embryonic development, which occurs during the fourth to twelfth week of pregnancy. The nerve cells (ganglia) cannot migrate into the nerve plexus of the so-called plexus myentericus, which is normally located within the muscles of the intestinal wall. To compensate for the missing immigration of the nerve cells into the intestinal wall, a nerve plexus in the intestine is connected upstream, which increases the release of the messenger substance acetylcholine.
Acetylcholine causes an increased activity of the intestinal muscles, so that the permanent tension (spasticity) of the intestinal muscles associated with the disease develops. In any case, a genetic component plays a role in the disease. The disease can be inherited autosomal-dominantly and autosomal-recessively. However, there are also many children who do not carry any of the typical gene mutations and in whom the disease has not been passed on via inheritance. If parts of the unborn child’s intestine are insufficiently supplied with blood or if a viral infection occurs, this can also be the trigger of the disease.