Intussusception: A Comprehensive Guide

Overview

Intussusception (in-tuh-suh-SEP-shun) is a serious condition in which part of the intestine slides into an adjacent part of the intestine. This "telescoping" often blocks food or fluid from passing through and cuts off the blood supply to the affected part of the intestine. It can lead to tearing of the intestine (perforation), infection, and death of bowel tissue.

Intussusception is the most common cause of intestinal obstruction in children younger than 3 years old. It's rare in adults, accounting for only about 5% of all cases of intestinal obstruction in adults. The condition affects approximately 1 in 1,200 babies before their first birthday, with about 60% of cases occurring between 4 and 10 months of age. Boys are affected more often than girls, with a ratio of about 3:2.

Key facts:

• Most common in infants and young children
• Peak incidence between 5 and 7 months of age
• About 1,500 cases per year in the United States
• 90% of cases occur in children under 2 years old

Sources: Mayo Clinic, National Institutes of Health

Symptoms

The classic symptoms of intussusception come and go, with periods of severe symptoms followed by periods with few or no symptoms. The most common signs and symptoms include:

Primary Symptoms

• Severe abdominal pain: The pain is typically sudden, intense, and colicky (comes in waves). Infants may draw their knees to their chest and cry loudly when the pain strikes.
• Blood and mucus in stool: Often described as "currant jelly" stool because of its appearance - a mixture of blood and mucus with a dark red color.
• Vomiting: May start as non-bilious (without bile) but can progress to bilious (greenish) vomiting as the obstruction continues.

Other Common Symptoms

• Abdominal swelling or distension
• Lethargy or extreme tiredness
• Diarrhea
• Fever (may indicate bowel tissue death or perforation)
• Lump in the abdomen (the intussuscepted portion may be felt by a doctor)
• Signs of dehydration (dry mouth, sunken eyes, decreased urine output)

Symptoms in Older Children and Adults

While rare in older children and adults, intussusception can occur. Symptoms may be less specific and can include:

• Chronic abdominal pain
• Nausea and vomiting
• Weight loss
• Gastrointestinal bleeding
• Change in bowel habits

Sources: Johns Hopkins Medicine, Centers for Disease Control and Prevention

Causes and Risk Factors

Causes in Children

In most childhood cases (about 90%), the cause of intussusception is unknown (idiopathic). However, several conditions are associated with intussusception:

• Viral infections: Some viruses, particularly adenovirus, may trigger intussusception. The rotavirus vaccine (RotaTeq) has been associated with a small increased risk.
• Anatomical abnormalities: Such as Meckel's diverticulum, polyps, or tumors (though these are rare in children).
• Recent abdominal surgery
• Cystic fibrosis
• Hench-Schönlein purpura (a condition that causes inflammation of blood vessels)

Causes in Adults

In adults, intussusception is usually caused by an underlying medical condition that serves as a "lead point" for the telescoping to occur. Common causes include:

• Tumors: Both benign (like lipomas) and malignant (like lymphomas or colorectal cancers)
• Adhesions (scar tissue from previous surgeries)
• Meckel's diverticulum
• Inflammatory bowel disease (Crohn's disease or ulcerative colitis)
• Celiac disease
• Recent abdominal surgery

Risk Factors

• Age: Most common between 6 months and 3 years
• Sex: Males are more commonly affected
• Recent viral infection
• Abnormal intestinal formation at birth (such as malrotation)
• Family history (though most cases are not inherited)
• Rotavirus vaccination: The risk is very small (about 1 extra case per 20,000-100,000 vaccinated infants)

Sources: NIH - Intussusception, World Health Organization

Diagnosis

Diagnosing intussusception requires a combination of medical history, physical examination, and imaging tests. Early diagnosis is crucial to prevent serious complications.

Medical History and Physical Examination

The doctor will ask about symptoms and perform a physical exam, which may reveal:

• A sausage-shaped mass in the abdomen
• Abdominal tenderness
• Signs of dehydration or shock in severe cases
• Blood in the stool (detected by rectal examination)

Imaging Tests

• Abdominal ultrasound: The preferred initial test. It's non-invasive and can show the "target sign" or "doughnut sign" characteristic of intussusception.
• Air or barium enema: Can both diagnose and sometimes treat intussusception. These tests show the obstruction and may help push the intestine back into place.
• Abdominal X-ray: May show signs of intestinal obstruction but is less definitive than ultrasound.
• CT scan: More commonly used in adults to identify the cause and location of intussusception.

Additional Tests

In some cases, especially in adults, additional tests may be needed to identify the underlying cause:

• Blood tests (complete blood count, electrolytes)
• Colonoscopy
• Biopsy of any suspicious tissue

Sources: Radiopaedia, UpToDate

Treatment Options

Intussusception is a medical emergency that requires prompt treatment to prevent serious complications. Treatment options depend on the severity, duration, and whether the intestine is damaged.

Non-Surgical Treatment (Enema Reduction)

In many cases, especially in children, intussusception can be treated without surgery using an enema. This procedure is both diagnostic and therapeutic.

• Air enema: Air is pumped into the colon through the rectum. The pressure often pushes the intussuscepted portion back into place. This is the most common method.
• Barium or contrast enema: Similar to air enema but uses liquid contrast. Less commonly used now due to potential complications.

Success rate: About 80-90% for children when performed within 24 hours of symptom onset. The procedure is typically done under sedation or anesthesia.

Surgical Treatment

Surgery is required if:

• The enema treatment fails
• The intestine is perforated
• There are signs of dead bowel tissue (gangrene)
• The child is very ill (shock, perforation, peritonitis)
• In most adult cases (due to likely underlying cause)

Surgical options include:

• Manual reduction: The surgeon gently pushes the intussuscepted portion back into place.
• Bowel resection: If the intestine is damaged, the affected portion is removed, and the healthy ends are sewn together.
• Laparoscopic surgery: Minimally invasive approach that may be used in some cases.

Post-Treatment Care

• Hospital observation: Typically 24-48 hours to monitor for recurrence (which happens in about 5-10% of cases).
• Intravenous fluids: To treat or prevent dehydration.
• Pain management: Appropriate pain relief medications.
• Follow-up imaging: To ensure the intussusception hasn't returned.

Treatment in Adults

Adults almost always require surgery because there's usually an underlying cause (like a tumor) that needs to be addressed. The specific surgical approach depends on the cause and location of the intussusception.

Sources: NIH - Intussusception Treatment, Mayo Clinic

Living with Intussusception

After successful treatment, most children recover completely with no long-term effects. However, there are some considerations for daily management and follow-up.

Recovery Tips

• Follow medical advice: Attend all follow-up appointments and complete any prescribed treatments.
• Monitor for recurrence: Be aware of the symptoms and seek immediate care if they return.
• Hydration and nutrition: Ensure adequate fluid intake and a balanced diet to support recovery.
• Pain management: Use prescribed pain medications as directed.
• Rest: Allow time for recovery, especially after surgery.

Dietary Considerations

After treatment, your doctor may recommend:

• Gradually reintroducing foods, starting with clear liquids, then soft foods, and finally regular diet.
• Avoiding foods that may cause constipation or gas initially.
• Breastfeeding or formula feeding can typically resume after recovery in infants.

Activity

• Avoid strenuous activities or heavy lifting for several weeks after surgery.
• Gradually increase activity levels as tolerated and as advised by your doctor.
• For children, normal play can usually resume once they feel well, but contact sports should be avoided until cleared by a doctor.

Emotional Support

Intussusception can be stressful for both children and parents. Consider:

• Talking to a counselor or therapist if anxiety persists.
• Joining support groups for parents of children with similar conditions.
• Explaining the condition to older children in age-appropriate terms to reduce fear.

Sources: HealthyChildren.org, National Institute of Diabetes and Digestive and Kidney Diseases

Prevention

Since the cause of most childhood intussusception is unknown, there's no sure way to prevent it. However, some general measures may help reduce risk:

General Prevention Tips

• Stay updated on vaccinations: While the rotavirus vaccine has a small associated risk, the benefits of vaccination outweigh the risks. The vaccine prevents many cases of severe diarrhea which can lead to complications.
• Practice good hygiene: Regular handwashing can help prevent viral infections that might trigger intussusception.
• Monitor diet: Ensure a balanced diet with adequate fiber to maintain healthy bowel movements.
• Stay hydrated: Proper hydration supports overall digestive health.

For Adults

Since adult intussusception is often caused by underlying conditions, early detection and management of these conditions may help:

• Regular screenings for colorectal cancer as recommended
• Managing inflammatory bowel disease effectively
• Prompt evaluation of any persistent abdominal symptoms

Sources: CDC - Vaccines, WHO - Vaccines

Complications

If left untreated, intussusception can lead to serious, life-threatening complications. Even with treatment, some complications may arise.

Immediate Complications

• Dehydration: From vomiting and inability to keep fluids down.
• Shock: Due to severe dehydration or infection.
• Peritonitis: Inflammation of the abdominal lining due to perforation.
• Sepsis: A life-threatening response to infection that can occur if bacteria enter the bloodstream through a perforated intestine.

Bowel-Related Complications

• Bowel obstruction: Complete blockage preventing food, fluid, and gas from moving through.
• Bowel ischemia: Reduced blood flow leading to tissue damage.
• Necrosis: Death of bowel tissue due to lack of blood supply.
• Perforation: A tear or hole in the intestine that can lead to infection.

Long-Term Complications

• Short bowel syndrome: If a large portion of intestine is removed, it can lead to malnutrition and digestive problems.
• Recurrence: Intussusception can come back, especially if there's an underlying cause.
• Adhesions: Scar tissue from surgery that can cause future bowel obstructions.

Complications in Adults

Adults are more likely to have underlying conditions that can lead to additional complications, such as:

• Spread of cancer if a malignant tumor is the cause
• Complications from inflammatory bowel disease
• Higher risk of bowel resection and associated complications

Sources: NIH - Complications of Intussusception, Mayo Clinic

When to Seek Emergency Care

Sources: American Academy of Pediatrics, Mayo Clinic