Hirschsprung Disease: Symptoms, Causes & Treatment in Children

What Is Hirschsprung Disease?

Hirschsprung disease is a congenital condition where nerve cells (ganglion cells) are missing from part of the large intestine, typically the rectum and lower colon. Without these nerve cells, the affected bowel segment cannot relax and push stool through, causing severe constipation or complete bowel obstruction. It affects approximately 1 in 5,000 newborns.

Hirschsprung disease, also known as congenital aganglionic megacolon, is a birth defect that affects the nerves in the walls of the intestine. During normal fetal development, nerve cells called ganglion cells develop throughout the intestine from the mouth all the way down to the anus. These nerve cells control the rhythmic muscle contractions that move food and waste through the digestive system.

In children with Hirschsprung disease, this nerve cell development stops before reaching the end of the intestine. The section without nerve cells cannot relax and contract normally, creating a functional blockage. Stool cannot pass through this segment, leading to backup and severe constipation or complete obstruction.

The condition is named after Harald Hirschsprung, a Danish physician who first described it in 1886 after observing two infants who died from severe constipation. Today, with early diagnosis and surgical treatment, most children with Hirschsprung disease go on to live normal, healthy lives.

Why Does Hirschsprung Disease Occur?

Hirschsprung disease occurs when ganglion cells fail to migrate completely along the developing intestine during the first 12 weeks of pregnancy. Normally, these nerve cells travel from the top of the digestive tract all the way to the anus. In Hirschsprung disease, this migration stops prematurely, leaving a segment of bowel without the nerve cells needed for normal function.

The exact cause of this incomplete migration is not fully understood, but researchers have identified several genes that play a role. The RET gene is the most commonly affected, found in about 50% of familial cases and 15-20% of sporadic cases. Mutations in other genes including GDNF, EDNRB, and SOX10 have also been identified.

How Much of the Intestine Is Affected?

The length of affected bowel varies significantly between patients. Understanding the extent of aganglionosis is important because it affects treatment approach and long-term outcomes.

In most cases (approximately 80%), only the rectum and lower part of the colon (sigmoid colon) are affected, spanning about 15-20 centimeters. This is called "short-segment" Hirschsprung disease and typically has the best outcomes after surgery. When a longer portion of the colon is involved, it's called "long-segment" disease. In rare cases, the entire colon or even part of the small intestine may lack nerve cells.

What Are the Symptoms of Hirschsprung Disease?

The hallmark symptom in newborns is failure to pass meconium (first stool) within 48 hours of birth. Other symptoms include abdominal distension (swollen belly), vomiting (often green-colored), and refusal to feed. Older infants may show chronic constipation, failure to thrive, and explosive diarrhea after rectal examination.

Hirschsprung disease symptoms can vary depending on the child's age and the length of affected bowel. However, the condition typically presents in the newborn period because the intestinal obstruction prevents normal bowel function from the start of life. Understanding these symptoms is crucial for early diagnosis and treatment.

Symptoms in Newborns

Most babies with Hirschsprung disease show symptoms within the first few days of life. The most important early sign is failure to pass meconium, the dark, sticky first stool that healthy newborns typically pass within 24-48 hours after birth. When a baby doesn't pass meconium within this timeframe, it raises suspicion for Hirschsprung disease or other intestinal problems.

As stool backs up behind the blocked segment, the abdomen becomes progressively more distended. The belly appears swollen and feels tight to the touch. This distension can become quite pronounced and uncomfortable for the baby. Vomiting often follows, and the vomit may be green or yellow (bile-stained), indicating intestinal obstruction.

Additional newborn symptoms include:

• Feeding difficulties: Babies may refuse to feed or feed poorly due to abdominal discomfort
• Irritability: Increased fussiness from abdominal pain and discomfort
• Explosive stool after rectal examination: When a doctor inserts a finger or instrument into the rectum, it may be followed by an explosive release of gas and stool
• Failure to gain weight: Poor feeding and intestinal problems prevent normal weight gain

Symptoms in Older Infants and Children

Some children, particularly those with very short-segment disease, may not be diagnosed until later in infancy or even childhood. These children typically present with chronic, severe constipation that doesn't respond well to standard treatments. Parents often describe that their child needs help to have bowel movements, such as stimulation with thermometers or suppositories.

Other symptoms in older children include:

• Chronic abdominal distension: A persistently swollen belly
• Poor weight gain or failure to thrive: The child doesn't grow as expected
• Malnutrition: The body cannot absorb nutrients properly when the intestine is obstructed
• Ribbon-like stools: Very thin stools when stool does pass
• Explosive diarrhea: Paradoxically, some children have explosive watery stools

When Should You Seek Medical Care?

Seek immediate medical evaluation if your newborn hasn't passed stool within the first 48 hours of life, or if your baby has a distended abdomen, green vomiting, or refuses to feed. For older children, consult a doctor for severe constipation that doesn't respond to standard treatment. Enterocolitis (fever, bloody diarrhea, distended abdomen) is an emergency.

Early recognition and diagnosis of Hirschsprung disease is essential for preventing serious complications. Parents and caregivers should be aware of the warning signs that require medical evaluation.

Contact Your Healthcare Provider Immediately If:

• Your newborn hasn't passed stool within 48 hours of birth
• Your baby has a swollen, distended abdomen
• Your baby is vomiting green or yellow fluid
• Your baby refuses to feed or is feeding very poorly
• Your older child has severe constipation that doesn't improve with dietary changes and laxatives

Seek Emergency Care Immediately If:

• Your child has a very distended, tight abdomen with signs of pain
• Your child has fever along with abdominal distension
• Your child has bloody, foul-smelling diarrhea and appears unwell
• Your child is lethargic, difficult to arouse, or not responsive
• Your child has signs of severe dehydration (no wet diapers, sunken eyes, no tears)

How Is Hirschsprung Disease Diagnosed?

Diagnosis involves a contrast enema X-ray showing a narrowed segment with dilated bowel above it, followed by rectal suction biopsy (the gold standard) confirming absence of ganglion cells. Anorectal manometry may be used to measure nerve reflexes. The biopsy definitively confirms the diagnosis by showing missing nerve cells and increased nerve fibers.

Diagnosing Hirschsprung disease requires a combination of clinical evaluation, imaging studies, and tissue analysis. When a doctor suspects Hirschsprung disease based on symptoms, they will order specific tests to confirm the diagnosis and determine the extent of affected bowel.

Initial Evaluation

The diagnostic process begins with a thorough medical history and physical examination. The doctor will ask about the timing of your child's first stool, feeding history, and any symptoms of constipation or abdominal distension. During the physical exam, the doctor will carefully feel the abdomen for distension and may perform a digital rectal examination. In Hirschsprung disease, this examination often triggers an explosive release of stool and gas.

Blood tests and urine tests may be ordered to assess the child's overall health and look for signs of infection or electrolyte imbalances. However, these tests cannot diagnose Hirschsprung disease; they help evaluate the child's condition and rule out other problems.

Contrast Enema (Barium Enema)

A contrast enema is usually the first imaging study performed when Hirschsprung disease is suspected. During this test, a liquid contrast material is gently inserted into the rectum through a small tube. X-ray images are then taken as the contrast fills the colon.

In Hirschsprung disease, the X-rays typically show a characteristic "transition zone" where the narrowed, aganglionic segment meets the dilated, normal bowel above it. The narrowed segment appears smaller because it cannot relax, while the bowel above it is stretched from accumulated stool. However, this transition zone may not always be visible, especially in newborns or children with total colonic involvement.

Rectal Biopsy: The Definitive Test

Rectal biopsy is the gold standard for diagnosing Hirschsprung disease. This test involves taking a small tissue sample from the rectal wall to examine under a microscope. There are two main approaches:

• Rectal suction biopsy: This can often be done at the bedside without anesthesia in young infants. A small suction device removes tiny tissue samples from the rectal mucosa and submucosa. The baby may be given sugar water (sucrose solution) for comfort during the procedure.
• Full-thickness rectal biopsy: This surgical procedure requires anesthesia and takes a larger, deeper tissue sample. It's typically reserved for cases where suction biopsy results are inconclusive or when more tissue is needed.

The pathologist examines the biopsy tissue looking for two key findings: absence of ganglion cells (nerve cells) and increased nerve fiber bundles. The presence of both findings confirms the diagnosis of Hirschsprung disease. Special staining techniques, including acetylcholinesterase staining and calretinin immunohistochemistry, help identify the nerve cell abnormalities.

Anorectal Manometry

Anorectal manometry is a specialized test that measures pressure and reflexes in the rectum and anal sphincter. In normal individuals, stretching the rectum causes the internal anal sphincter to relax—this is called the rectoanal inhibitory reflex (RAIR). In Hirschsprung disease, this reflex is absent because the nerve cells that coordinate this response are missing.

While this test can support the diagnosis, it's not always reliable in very young infants and cannot replace biopsy for definitive diagnosis. It's most useful in older children or when the diagnosis is uncertain.

Additional Testing

Once Hirschsprung disease is diagnosed, additional tests may be recommended:

• Cardiac ultrasound (echocardiogram): To check for associated heart defects
• Kidney ultrasound: To check for urinary tract abnormalities
• Genetic testing: To identify any genetic mutations and assess familial risk
• Evaluation for associated syndromes: Particularly Down syndrome and other conditions

How Is Hirschsprung Disease Treated?

Treatment is surgical removal of the affected bowel segment (pull-through surgery). Before surgery, bowel irrigations with saline help decompress the intestine. Some very ill children may need a temporary colostomy first. After surgery, children typically stay in hospital for several days. Most children have excellent long-term outcomes, though some bowel difficulties may persist during childhood.

The only effective treatment for Hirschsprung disease is surgery to remove the section of bowel that lacks nerve cells. However, the timing and approach to surgery depend on the child's overall condition, the extent of disease, and whether complications are present.

Pre-Surgical Management: Bowel Irrigation

Before surgery, most children with Hirschsprung disease need bowel irrigations (also called rectal washouts) to decompress the intestine and prevent complications. This involves inserting a soft catheter into the rectum and gently flushing warm saline solution into the bowel, then allowing the fluid and stool to drain out.

Parents are taught to perform these irrigations at home, typically several times per day. The procedure helps:

• Remove accumulated stool and gas
• Reduce abdominal distension
• Prevent enterocolitis
• Allow the bowel to decompress before surgery
• Improve the child's nutritional status

Learning to perform bowel irrigations can feel overwhelming for parents at first, but healthcare teams provide thorough training and support. Having two caregivers learn the technique is helpful, as irrigations may be needed multiple times daily until surgery.

Definitive Surgery: Pull-Through Procedure

The definitive surgical treatment for Hirschsprung disease is called a "pull-through" procedure. The goal is to remove the aganglionic (nerve-free) segment of bowel and connect the healthy, normally-innervated bowel directly to the anus, preserving anal sphincter function for continence.

Several surgical techniques exist, and the choice depends on the surgeon's experience and the child's specific situation:

• Soave procedure: The mucosa (inner lining) of the aganglionic segment is removed, and healthy bowel is pulled through the remaining muscular sleeve and connected near the anus.
• Duhamel procedure: The healthy bowel is brought down behind the aganglionic rectum and a side-to-side connection is made, leaving some of the original rectum in place.
• Swenson procedure: The entire aganglionic segment is removed close to the anus, and healthy bowel is directly connected to the anal canal.
• Transanal pull-through: A minimally invasive approach where the entire operation is performed through the anus, avoiding abdominal incisions in many cases.

Today, many pull-through surgeries are performed using minimally invasive techniques (laparoscopic or transanal approaches), which can reduce recovery time and complications. The surgery is typically performed under general anesthesia, and children usually stay in the hospital for several days to a week afterward.

Staged Approach: When a Colostomy Is Needed

Some children are too ill for immediate pull-through surgery. This may occur if the child has severe enterocolitis, bowel perforation, or is critically unwell. In these cases, a staged approach is used:

First stage: A colostomy is created. The surgeon brings healthy bowel through an opening in the abdominal wall, creating a stoma where stool drains into an external pouch. This diverts stool away from the obstructed segment and allows the child to recover.

Second stage: Once the child has recovered and grown, typically after several weeks to months, the definitive pull-through surgery is performed. The colostomy is reversed, and the healthy bowel is connected to the anus.

While having a colostomy can be challenging for families, it's sometimes the safest option for very sick children. Healthcare teams provide extensive education on stoma care before discharge.

Post-Operative Care and Recovery

After pull-through surgery, children typically experience frequent, loose stools—sometimes 10-20 bowel movements per day initially. This is normal and expected as the intestines adjust to the new anatomy. Parents should be prepared for frequent diaper changes and should protect the skin around the anus with barrier creams to prevent irritation and breakdown.

Recovery milestones include:

• First few days: Clear liquid diet, advancing to breast milk or formula as tolerated
• First few weeks: Very frequent stools (10-20+ per day), gradually decreasing
• First few months: Stool frequency decreases but remains higher than normal; skin care remains important
• First few years: Gradual improvement in bowel control and stool frequency

What Is Life Like After Hirschsprung Disease Surgery?

Most children with Hirschsprung disease grow and develop normally after surgery. However, many experience bowel difficulties during childhood including frequent stools, soiling, and constipation. Bowel function typically improves through childhood and adolescence. Adults with Hirschsprung disease generally have fewer problems than they did as children.

Following successful surgery, the vast majority of children with Hirschsprung disease go on to live normal, active lives. However, it's important for parents to understand that some ongoing bowel issues are common during childhood and usually improve over time.

Common Long-Term Challenges

While surgery cures the obstruction, it doesn't create a completely normal intestinal system. Many children experience some combination of the following issues during childhood:

• Frequent bowel movements: Children may need to use the toilet more often than their peers
• Fecal soiling (encopresis): Stool leakage into underwear, especially during the early years after surgery
• Constipation: Paradoxically, some children develop constipation that may require ongoing management
• Difficulty sensing the need to go: Reduced sensation in the rectum can make it harder to recognize when a bowel movement is coming
• Difficulty controlling bowel movements: Weakened sphincter control may lead to urgency or accidents

These challenges occur because the surgery, while life-saving, cannot fully replicate normal nerve and muscle function. The rectum's sensory function may be diminished, and the coordination between bowel and sphincter may not be perfect.

Strategies for Managing Bowel Function

Several approaches can help manage ongoing bowel issues:

• Regular toilet sitting: Establishing a routine of sitting on the toilet at consistent times (such as after meals) can help train the bowel
• Dietary management: Adequate fiber and fluid intake support healthy bowel function
• Medications: Laxatives or stool softeners may be needed for constipation; sometimes medications to slow the bowel are helpful for frequent stools
• Bowel management programs: Structured programs including enemas or irrigations can help children achieve social continence
• Biofeedback: This therapy can help older children learn to recognize and respond to bowel signals

Toilet Training

Children with Hirschsprung disease may take longer to achieve reliable toilet training than their peers. Starting toilet training early with regular toilet sitting can be beneficial. Using a child-sized potty or toilet seat with a footstool helps the child position their body properly for effective bowel movements.

It's important for parents to be patient and supportive during this process. Some children may need adaptive strategies or bowel management programs to achieve continence. Working with your healthcare team can help identify the best approach for your child.

Long-Term Outlook

The good news is that bowel function typically improves as children grow. Several factors contribute to this improvement:

• The pelvic floor muscles strengthen with age and development
• Children become more aware of their body's signals
• The intestines adapt over time to the new anatomy
• Children develop coping strategies and routines

By adolescence and adulthood, most individuals with Hirschsprung disease have significantly better bowel function than they did as young children. Many adults report minimal or no ongoing issues, though some may continue to experience occasional constipation or looser stools than average.

What Are the Complications of Hirschsprung Disease?

The most serious complication is Hirschsprung-associated enterocolitis (HAEC), a potentially life-threatening bowel inflammation. Other complications include bowel perforation, chronic constipation, fecal incontinence, and nutritional problems. Enterocolitis can occur before or after surgery and requires prompt treatment with bowel irrigation and antibiotics.

While most children with Hirschsprung disease do well with treatment, complications can occur both before diagnosis/surgery and in the long term. Understanding these potential problems helps parents recognize warning signs and seek appropriate care.

Enterocolitis: The Most Serious Complication

Hirschsprung-associated enterocolitis (HAEC) is inflammation of the intestine that can occur in children with Hirschsprung disease. It's the leading cause of death and illness associated with the condition. Enterocolitis can occur before surgery (when the bowel is obstructed) or after surgery (due to residual abnormalities or strictures).

The condition develops when bacteria accumulate in the dysfunctional bowel, leading to overgrowth and toxin production. The intestinal lining becomes inflamed and damaged, which can progress to severe illness or even death if not treated promptly.

Symptoms of enterocolitis include:

• Fever
• Abdominal distension and tenderness
• Explosive, foul-smelling diarrhea (often bloody)
• Lethargy and poor feeding
• Dehydration
• Shock in severe cases

Treatment of enterocolitis involves:

• Frequent bowel irrigations to decompress the bowel and remove bacteria/toxins
• Intravenous antibiotics to fight infection
• Intravenous fluids for hydration
• Stopping oral feeding temporarily
• Hospitalization for monitoring and treatment

Some children are prone to recurrent episodes of enterocolitis. These children may need ongoing bowel irrigation programs and close monitoring.

Other Complications

Before or without surgery:

• Bowel perforation: The obstructed, distended bowel can develop a hole, leading to peritonitis (infection of the abdominal cavity)
• Severe malnutrition: Chronic obstruction prevents normal nutrient absorption
• Sepsis: Bacteria from the bowel can enter the bloodstream

After surgery:

• Anastomotic stricture: Scarring at the surgical connection site can cause narrowing and obstruction
• Anastomotic leak: The surgical connection can develop a hole, requiring additional surgery
• Residual aganglionosis: If some aganglionic bowel remains, symptoms may persist
• Chronic constipation: Ongoing difficulty with bowel movements
• Fecal incontinence: Inability to control bowel movements
• Perianal skin breakdown: From frequent stools irritating the skin

What Causes Hirschsprung Disease?

Hirschsprung disease is a congenital condition that develops during early pregnancy when nerve cells fail to migrate completely along the developing intestine. It has a genetic component, with several genes identified (especially RET gene). The condition is more common in males and is associated with Down syndrome in about 10% of cases.

Hirschsprung disease results from abnormal development of the enteric nervous system during the first trimester of pregnancy. Understanding the causes helps parents appreciate why the condition occurred and assess the risk for future children.

Embryological Development

During normal fetal development, specialized cells called neural crest cells migrate along the developing intestine, eventually becoming the ganglion cells that control bowel function. This migration begins around week 5 of pregnancy and normally reaches the anus by week 12.

In Hirschsprung disease, this migration stops prematurely, leaving the final portion of the intestine without ganglion cells. The reasons for this failed migration include genetic factors and possibly environmental influences, though the exact triggers are not fully understood.

Genetic Factors

Hirschsprung disease has a significant genetic component. Several genes have been identified that, when mutated, can cause or increase the risk of the condition:

• RET gene: The most commonly affected gene, found in about 50% of familial cases and 15-20% of sporadic cases. The RET protein is essential for the survival and migration of neural crest cells.
• EDNRB gene: Encodes a receptor that plays a role in nerve cell development
• EDN3 gene: Produces a protein that interacts with the EDNRB receptor
• GDNF gene: Produces a growth factor important for nerve cell survival
• SOX10 gene: Involved in neural crest cell development

The inheritance pattern is complex. Most cases occur sporadically (without family history), but when there is a family history, the risk for future children is increased. The risk is higher with long-segment disease than short-segment disease.

Associated Conditions

Hirschsprung disease occurs in isolation in most cases, but it can be associated with other conditions:

• Down syndrome (Trisomy 21): About 10% of children with Hirschsprung disease also have Down syndrome
• Waardenburg syndrome: A condition affecting pigmentation and hearing
• Congenital heart defects: Some children have associated heart abnormalities
• Urogenital anomalies: Kidney or urinary tract problems
• MEN2 (Multiple Endocrine Neoplasia type 2): Associated with certain RET mutations

Many pediatric surgical centers offer genetic counseling and testing for families affected by Hirschsprung disease. This can help identify any underlying genetic syndromes and provide information about risks for future pregnancies.