Definition
Definition
Hirschsprung's disease, also known as congenital intestinal aganglionosis, is a rare genetic disorder of the digestive system that manifests in childhood.
It is due to the lack of migration of certain cells that allow the transmission of information at the colon level. This results in chronic and significant constipation in its form, manifesting in adults.
Symptoms
Symptoms
Symptoms of Hirschsprung's disease include:
- This pathology can be revealed from birth by significant bloating of the abdomen, the newborn not evacuating its meconium (first stools passed after birth).
- More generally, the affected child has rare, extremely hard stools that are very difficult to pass, sometimes alternating with episodes of diarrhea (a sign of inflammation of the small intestine and colon,enterocolitis).
- Stool stagnates above the rectal ampulla (the segment between the rectum and the anus). Thus, upon palpation, the abdomen is swollen, but a rectal examination finds no fecal matter in the rectal ampulla. These two signs are characteristic of the disease.
- Percussion of the abdomen (gently tapping with a finger) produces a louder sound than normal. This reflects distension of the intestine due to gas accumulation.
- Since there are several levels of Hirschsprung's disease, the symptoms will vary depending on the degree of involvement.
- It can sometimes be revealed simply by forms of chronic constipation, that is to say more or less stubborn, lingering constipation, which can be complicated by obstruction of the intestine, and sometimes even inflammation of the intestine, leading to what is called a acute enterocolitis.
- A child's growth delay can sometimes guide the diagnosis.
Pathophysiology
Hirschsprung's disease is a disease congenital due to the partial or total absence of nerve ganglia, whose role is to allow the proper functioning of the muscles of the intestine (and more particularly of the colon).
These lymph nodes are located inside the wall of the intestine, in areas called Meissner and Auerbach plexusThis disease, which mainly occurs in newborns and infants between 3 and 5 months old, affects:
- Le colon (large intestine).
- Le sigmoid (last part of the colon, before the rectum).
- Le right (segment located between the colon and the anus).
Epidemiology
Its frequency is approximately 1 case per 5000 births. It affects 4 out of 5 boys.
It occurs during pregnancy and reflects an embryological malformation: in fact, the nerve cells intended to colonize the intestinal wall do not migrate from their place of production (called the neural crest).
Medical exam
Additional examination
Additional examinations are:
- L'electromyography : is a test that records the spontaneous electrical activity of a muscle or nerve. It is used to differentiate a disorder of psychological origin from an organic attack. Thanks to recordings of the small intestine and colon, it is possible to study the movements of digestive peristalsis. Electromyography is performed either in a doctor's office or in a hospital consultation. It does not require any special preparation.
- La manometry : is the study of pressures inside the digestive tract. It also allows for the identification and study of digestive motility abnormalities. This examination involves inserting several balloons into the rectum, connected to a pressure recording device.
Cause
Cause
The absence of Meissner and Auerbach plexus results in the absence of peristalsis, which is the set of muscular contractions allowing the progression of the contents inside a hollow organ. Concerning the digestive tract, it is the progression of food from the mouth (more precisely from the pharynx) to the rectum. This physiological phenomenon, also called digestive motility, is a spontaneous mechanism of the digestive tract. Without peristalsis, the mixing of food and the absorption of nutrients, that is, the elements contained in food, are impossible.
Hirschsprung's disease causes significant abdominal distension. When stool and gas reach the part of the intestine lacking the Meissner and Auerbach plexuses, they no longer move forward. This results in an increase in volume (dilation) of this part of the intestine. There are different degrees of severity of the disease depending on the number of missing plexuses. The more the affected area is lacking, the more severe the problems are. Fortunately, in the majority of cases, this area lacking lymph nodes is limited to the colon sigmoid (terminal part of the colon, preceding the rectum).
Treatment
Treatment
The treatment of Hirschsprung's disease consists of introducing a probes in the rectum, or to perform small enemas cautious. This is intended to allow the stool to pass, but this technique is not effective in all cases.
In cases where this medical treatment is ineffective, what is called a colotomy [and not a colostomy (with an S) which is the creation of an artificial anus by connecting a portion of the colon to the skin]. This technique consists of making a surgical opening of the colon wall, thus allowing its exploration. It sometimes allows the discovery of anomalies, but also the removal of small benign tumors such as polyps, which protrude inside the intestinal cavity. During intestinal obstruction, the colotomy allows the decompression and evacuation of the colon. However, this technique presents some dangers, in fact, due to the high risk of dissemination of microbes that it entails, and it requires special precautions for its realization, which must be done in very good aseptic conditions. colotomy is recommended until final correction.
When the entire colon is affected, a colostomy is then necessary.
Lileocolostomy is a surgical operation that involves connecting the terminal part of the small intestine to the colon. This operation allows the continuity of the digestive tract to be restored after a partial removal (in this example, part of the colon). After this removal of the pathological portion of the colon, the segment of l'ileum is attached to the remaining segment of colon, with wire, or staples. Ileocolostomy does not generally have any consequences on the functioning of the digestive tract. The operation can be performed from six months, if the child's general condition allows it. Some surgeons believe that an intervention of this type can be performed earlier. When the entire colon is affected, it is the ileum normally innervated, which must be brought to the level of the rectum, or even the anus. The aim is to remove the intestinal areas no longer containing plexus de Meissner et d'Auerbach, and to connect the normally functioning intestines to the terminal part of the digestive tract, that is to say the rectum if it has plexus "in working order", if not to the anus.
Evolution
Premature
Complications of Hirschsprung's disease include:
- The most formidable is l'enterocolitis, who is inflammation of the mucous membranes of the small intestine and colon. It can be:
- Infectious : caused by a parasite, virus or bacteria, it can be due to the ingestion of contaminated food or transmission between individuals. It is characterized by liquid, bloody diarrhea, vomiting, severe abdominal pain. Fever is not systematic.
- Bacterial : caused by a bacterium which destroys the mucous membrane (Shigella, Salmonella or Yersinia), and by intestinal or digestive tuberculosis (mainly in immunocompromised patients and/or those with AIDS).
- viral : it mainly affects children and heals spontaneously (except in immunocompromised patients and/or those with AIDS, in whom it can cause serious lesions).
- Parasitic : most frequently due toamoebiasis, and at giardiasis.
- Inflammatory : and non-infectious. It is essentially the Crohn's disease (chronic inflammatory disease).
- La sepsis, that is to say an invasion of the blood by bacteria pathogens.