HIRSCHSPRUNG’S DISEASE

Hirschsprung’s disease is a congenital anomaly that affects the rectum and the last part of the colon and results in not being able to adequately emptystool. This occurs when some of the nerve cells (ganglia) that are normally located in the intestinal wall do not form properly during fetal development.

Under normal conditionsganglioncells control the muscle the intestinal wallto create peristaltic intestinal movements, advancing gas and feces in its lumen.

Children with Hirschsprung’s disease do not have ganglion cells in the rectum or final part of the large bowel (aganglionic colon), and as a result, peristaltic movements are reduced ormissing and relaxation of the muscles does not occur. Therefore, gas and feces have great difficulty to pass through the affected segment and accumulate in the intestinal tract.This can result in partial or complete obstruction of the bowel and mayeven lead to rupture (bowel perforation). In some cases, a bacterial infection may developcalled enterocolitis or occasionally toxic megacolon.

Hirschsprung’s disease occurs in 1:5.000 live births and is more common in boys (4: 1 male to female ratio).About 80% of patients with Hirschsprung’s disease have no family history. However, if a parent has Hirschsprung’s disease, their child has 1% chance of suffering from it too. If a family has a child with Hirschsprung’s disease, the chance of having another child with it is between 3%and12%.

Sixty-four percent of children are being diagnosed during the first three months of life and 80% by the end of the first year. However, a small percentage of patients (8%) can be diagnosed much later. This usually concerns cases of ultra-short segment congenital megacolon (aganglionic section <5 cm) that can be easily remain undiagnosed.

CLASSIFICATION - TYPES

Hirschsprung’s disease is classified according to the extent of the affected colon (aganglionic – without ganglion cells) into:

Ultra-short segment (2-3%): absence of ganglion cells in the last 2 to 3 cm of the rectum
Orthosigmoid or shortsegment (70-80%): absence of ganglion cells in the rectum and sigmoid (the last part of the colon)
Long segment (10-20%): absence of ganglion cells in 1/3 of the colon
Total colonic aganlionosis (7-8%): it is characterized by the absence of ganglion cells along the entire colon.

COEXISTING DISEASES

Down Syndrome, Smith-Lemli-Opitz, Shah-Waardenburg, Cartilage-hair hypoplasia, Congenital hypoventilation (“Ondine curse”) syndrome
Urogenital diseases
Cardiovascular diseases
Cleft lip and palate
Microcephaly
Micrognathism
Hydrocephalus
Delayed growth
Mental retardation
Autism

DIAGNOSIS

Almost all children with Hirschsprung’s disease are diagnosed during the first 2 years of life and half of these children before the age of 1. However, a small number are diagnosed much later in childhood or adulthood.

The diagnosis of Hirschsprung’s disease will be suspectedby the clinical presentation, and laboratory tests (imaging, manometry). However, the diagnosis is confirmed by the histopathological examination of a rectal biopsy.

80% of children with Hirschsprung’s disease develop symptoms in the first 6 weeks of life. Newborns affected by this disease usually develop symptoms during the first48 hours of life. However, some children may not have symptoms for several months or even years.

CLINICALPRESENTATION

Hirschsprung’s disease in infancy manifests itself in 70-80% of patients with abdominal distension, bilious vomiting and delayed passage of meconium, as well as “explosive” diarrhea that follows phases of constipation. In 30% of newborns it manifests with severe enterocolitis (acute abdominal distension, explosive foul-smelling diarrhea with blood, respiratory distress and tachycardia. It can rarely cause bowel rupture and peritonitis.

In infancy the disease manifests with chronic constipation, small stools like pellets (like goat feces), colic-like abdominal pain, progressive abdominal distention and palpable fecal masses. Constipation usually begins with the introduction of cow’s milk feeding after cessation of breastfeeding. This happens because during breastfeeding stools are relatively liquid and pass more easily through the affected part of the intestine. Rarely, severe enterocolitis may occur in infancy, with diarrhea, fever, abdominal distention, electrolyte disturbances, edema, and hypoproteinemia.

In preschool and older children, the disease is manifested by chronic constipation, lower frequency of stool passage, abdominal distension, palpable stool masses, failure to thrive, anemia and in a small percentage with clinical manifestations of intestinal obstruction.

LABORATORY TESTS

Abdominal x-ray: This test is the first step in assessing the patient and it will demonstrate intestinal obstruction. However, it does not establish a definitive diagnosis of Hirschsprung’s disease.

Contrastenema: This test uses a combination of abdominal x-ray with contrast enema. The contrast allows betterdemonstration of the intestine on the X-ray and is the most useful imaging test for the diagnosis of Hirschsprung’s disease.

Rectal manometry: It measures the pressure of the rectum and anus by determining whether the anorectal reflex is present.

Histopathology. The histopathological diagnosis of Hirschsprung’s disease with rectal biopsy is necessary and imperative to document the disease, before the surgeon proceeds with surgical treatment. Tissues can be obtained in two ways.

Suction biopsy of the rectal mucosa and submucosa is performed with a special forceps (Noblett). It’s advantages over full-thickness biopsy are that it does not require general anesthesia, hospitalization, surgery, nor complicated preoperative or postoperative care, hasfew complications and is technically easy. This is the investigation of choice to confirm the diagnosis in the neonatal period.
Full thickness rectal biopsy. If suction biopsy does not provide safe conclusions, then a full-thickness biopsy is performed under general anesthesia in the operating room.

Confirmation of Hirschsprung’s disease is done with a special pathological processing of tissue obtained by biopsy(histological, histochemical and immunohistochemical), in specialized laboratories.

TREATMENT

Almost all children with Hirschsprung disease will require surgery known as “pull-through”.

Endorectal pull-through and Duhamel surgery are the most widely used surgical procedures. At present, there is no evidence to support the superiority of one of the two techniques in terms of surgical complications or long-term bowel function. The latest guidelines state that each center should perform the procedure they are most familiar with, including follow-up, and management of postoperative complications.

Timing of the operation is determined individually foreach case. There is a possibility to perform the main restorative surgical procedure in a single stage, without colostomy. However, this depends on various factors such as early diagnosis and the length of the aganglionic bowel. In most cases this is not possible and when the patient cannot empty his bowel with enemas, and has a significantly enlarged bowel, a stomais judged necessary.

The stomais temporary and is placed in the part of the intestine that is functioning normally and the child can eat and thrive. The main operation is performed in a second stage with simultaneous closure of the stoma.

All patients receive careful postoperative care in the days following their operation. In the long term somepatients may experience constipation, diarrhea or fecal incontinence after surgery. For this reasons follow-up is needed and some patients require treatment with a combination of diet, medication, and enemas.

Few complex patients require further management for longer periods of time. These patients benefit from the BOWEL MANAGEMENT PROGRAM.

POSTOPERATIVE CARE

The immediate postoperative period after pull through surgery is usually without complications. Postoperative pain is managed, feeding is started immediately after bowel mobilization and parents can be by their children’s side during hospitalization. The length of stay depends on eachindividual case. During the operation, absorbable sutures are used and no intervention is required to remove them.

After the main operation and the closure of the colostomy that are performed simultaneously, the patient has many soft or even watery stools for a short period of time. This can cause skin irritation around the anus (diaper rash). Within a few weeks of surgery, bowel movements subside in frequency and become harder in texture.

Then the number of bowel movements normally decreases, and most patients will experience some degree of constipation. After about 6-12 months, depending on eachindividual patient, bowel movements usually return to normal. However, some children may have problems in the longer term.

That is the reason why all patients who have undergone anorectal surgery need postoperative follow-up for bowel habits for a significant period of time depending on the type and severity of the malformation, and patients response to treatment.

Our team will work closely with you to improve these problems.

PROBLEMS OF BOWEL FUNCTION(FUNCTIONAL DISORDERS) THAT MAY EXIST AFTER THE REHABILITATION OF HIRSCHSPRUNG’S DISEASE - TREATMENT

A significant number of patients with Hirschsprung’s disease, even after their rehabilitation, may experience problems such as constipation, stool incontinence.

Even technically excellent surgery does not ensure a perfect bowel function. This of course depends on many factors: severity of the anomaly, ength of the aganglionic gut, timing of surgery, dilatation of the proganglionic gut, motility disorders, and others.

In some cases, these problems are minor and easy to treat. Occasionally, when they are significant and affect the control of bowel movements, they create psychological difficulties in social adjustment and need a long term support of a team of specialized medical, nursing, and psychologyteams.

Some patients may experience pseudo-diarrhea due to overfilling (severe constipation). These patients have a dilated megarectum, which is the cause of their symptoms.

Approximately 90% of these patients, with the BOWEL MANAGEMENT PROGRAM, finally have satisfactory control of defecation. Of these, about 30% will eventually undergo surgical removal of the distended bowel with positive functional results.

Children who have undergone pull through surgery may gain control of bowel habits and sensation of the urge to defecate slower compared to unaffected children.

A small number of children have a negative behavior related to the defecation process. This is due either to insufficient training or to psychosomatic inhibitions resulting from pain experiences, poor enema performance, etc. Education for continence should begin at three or four years of age. If the child is still using a diaper, unlike other children of their age, the care team will help address the problem.

In other children the type of congenital megacolon (total aganglionic bowel, etc.) may not allow them to have full control of bowel movements and urgencies for defecation or may present with severe constipation.

These problems are addressed withthe implementation of a BOWEL MANAGEMENT PROGRAM, which includes a combination of diet, medication, enemas, physiotherapy, psychological support and/or other measures resulting in the improvement or restauration of bowel disorders.

The results are encouraging, as it seems that many children show an improvement both in their constipation and continence.

During the BOWEL MANAGEMENT PROGRAM bowel function is monitored on a daily basis.

When patients are clean during the day for three consecutive days, the treatment is considered successful and the program is adopted for a daily routine by the patient and his family.

In case the patient continues to experience problems despite the efforts through the “Bowel Management Program” a permanent colostomy or an appendicostomy for administration of the enemas (Malone operation) is proposed.

Addressing disorders of bowel function in patients with Hirschsprung’s disease is a difficult and important part of their treatment.

In order to improve the quality of life of these patients, the cooperation of the patient and parents with the responsible physician and a multidisciplinary team of our center (pediatric surgeons – urologists, pediatric gastroenterologists, specialized nurses, nutritionists, psychologists, physiotherapists)with individualized criteria, results in the improvement and successful management of these disorders.

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