Hirschsprung’s disease is caused by a defect in the innervation of part of the colon. It affects 1 in 5000 infants. Causes, symptoms, development, treatments, operation with Dr Caroline Chamond, pediatric surgeon.
There Hirschsprung’s disease, also called “megacolon”, corresponds to a form of severe constipation and is one of the most frequent diseases of the digestive tract. If it develops very early in pregnancy, it is most often diagnosed at birth and can be treated. Discovered with Dr Caroline Chamond, pediatric surgeon at the Estuaire private hospital in Le Havre.
To be taken very seriously, Hirschsprung’s disease affects approximately 1 in 5000 births. Also called the “congenital megacolon”, it affects the rectum, sometimes the entire colon and can extend to the small intestine. This is a lack of innervation of part of the colon. Normally, this contracts to move the stool from the beginning of the colon to the rectum, “it’s like a tube that moves like a snake”image Dr Caroline Chamond, pediatric surgeon in Le Havre. This contraction depends on the nerves. During the development of the embryo – between the 5th and the 8th week – the colon is put in place then the nerves are installed first by the right part of the colon and progress to the bottom of the rectum. From time to time, the movement stops. The part that has no nerves therefore does not work.
A child suffering from a classic form of Hirschsprung’s disease must be able, once operated, live long and normally, assures Dr. Chamond. On the other handif the entire colon is affected, life can be more complicated because it is necessary to recreate a reservoir from the intestines. “The child will have to undergo operations several timesmay have difficulty eating like the others. All treatments can have an impact on life expectancy.” Finally, if the entire intestine is affected by the disease, the child unfortunately cannot live.
The part of the device that does not work does not allow anything to pass: neither gases nor stools.. It is then necessary to imagine a rigid and completely blocked tube. “Everything that will accumulate before then cannot be evacuated”, says Dr. Chamond. This then widens the colon although the problem is, in most cases, the rectum. “In the majority of cases, we realize this within 48 hours of birth because newborns are supposed to pass meconium (the first stool) within the first 24 hours”, explains the pediatric surgeon. “When there is a delay in meconium, it puts us in the ear”. Sometimes Hirschsprung’s disease can go unnoticed for some time. “Some babies may have a bit of gas and stool at first when only a small part of the rectum is not functioning.”
In 20% of cases, it is a family genetic anomaly
The disease occurs early in the development of the embryo. In 20% of cases, it is a family genetic anomaly. But in 80% cases, we are witnessing a new malformation without any family history. “We don’t really understand the why and how. We simply manage to grasp the mechanism and identify the responsible gene which is, in the majority of cases, the RET gene found in the non-sex chromosomes 3 and 19″. details Caroline Chamond.
If the disease is not diagnosedthe child’s belly swells, his veins stand out, he eats little or even more. Intestinal infection can also pass into the blood: this is called a sepsis. The bowel can also perforate due to gas not escaping, leading to peritonitis. It is then necessary to go to the operating room, clean, wash, put the child on antibiotics and feed him through the veins. “If we do nothing at all, the child may die. The first weeks are those during which we must be very vigilant”, warns the surgeon.
When there are doubts at birth, the doctors perform a biopsy : “You have to take a small piece of the walls of the rectum. We do it either by natural means, without anesthesia, thanks to a specific forceps called the Sheye forceps, or we perform a surgical biopsy: we put the child to sleep and then we analyze the sample. explains the surgeon. This biopsy can confirm or rule out the presence of the disease. Secondly, if Hirschsprung’s disease is diagnosed, it is necessary to know how long it extends. For this, Dr. Chamond performs an enema: “On injects a contrast product into the anus then standard imaging takes a photo of the colon which highlights the transition zone between the part that works and the part that does not work”. It is possible that a diagnosis will be established late. The surgeon has, for example, already had the case of a six-year-old girl who had not been diagnosed before.
During an emergency when a child has an obstruction, there is two ways to evacuate gases and stools. Either by a enema called “nursing” : a probe is directly inserted into the anus for 10 to 15 cm and allows excrement to escape through the probe. The belly then deflates and the children are better able to eat. If the nursing is effective, the parents learn how to do it and the children can go home. If nursing is not effective, a stoma (pouch that collects the stool) is installed. It also helps to decompress the belly and the children can go home and keep it for several months.
The operation consider as soon as possibledepending on the weight of the child. “It is more comfortable to operate when they regain weight. If the nursing is effective, we can wait about three months.” The operation also depends on the form of the disease. If it is necessary to remove the entire colon, the stoma is left longer. THE The aim of the surgery is to remove the part without nerves and connect the healthy area at the anal margin. The pediatric surgeon wishes to point out that after the operation, the sphincter, whose role is to close the rectum to avoid incontinence, is not affected. Some children might have a little trouble being continent, re-educating the muscles, thanks to physiotherapy sessions, the children must be able to be clean and live like everyone else.
Thanks to Dr Caroline Chamond, pediatric surgeon at the Estuaire private hospital in Le Havre.