Justin cried loudly and drew his tiny legs up to his chest as his bewildered parents tried to soothe him. Their 7-month-old had been colicky before, but this was something new — his crying was more urgent, his mood much more irritable. Justin's dad noticed that his son's small belly was distended, and when it was time to change the baby's diaper, he suspected that something was wrong.

After speaking with Justin's doctor, Justin's dad bundled him up and took him to the emergency department, where he was diagnosed with and successfully treated for intussusception, the most common abdominal emergency affecting children under 2 years old.

About Intussusception

Intussusception occurs when one portion of the bowel slides into the next, much like the pieces of a telescope. When this occurs, it can create a blockage in the bowel, with the walls of the intestines pressing against one another. This, in turn leads to swelling, inflammation, and decreased blood flow to the part of the intestines involved.

Intussusception:

• occurs most often in babies between 5 and 10 months of age (80% of cases occur before a child is 24 months old)
• affects between 1 and 4 infants out of 1,000
• is more common in boys than in girls

Signs and Symptoms

Infants and children with intussusception have intense abdominal pain, which often begins very suddenly and causes loud, anguished crying causing the child to draw the knees up. The pain is usually intermittent, but recurs and may become stronger. As the pain eases, the child may stop crying for a while and seem to be feeling better.

Other symptoms may include:

• abdominal swelling or distention
• vomiting
• vomiting up bile, a bitter-tasting yellowish-green fluid
• passing stools (or poop) mixed with blood and mucus, known as currant jelly stool
• grunting due to pain

As the illness progresses, a child may become progressively weaker and may develop a fever and appear to go into shock. Some babies will only have the symptom of drowsiness when they have intussusception.

Causes

In infants, the causes of intussusception are unknown. Because it is seen most often in spring and fall, though, some theories suggest a possible connection to the kinds of viruses that kids catch during these seasons, including upper respiratory infections.

In some cases, intussusception may follow a recent bout of gastroenteritis (or "stomach flu"). Bacterial or viral gastrointestinal infections may cause swelling of the infection-fighting lymph tissue that lines the intestine, which may result in pulling one part of the intestine into the other.

In kids younger than 3 months or older than 5 years, intussusception is more likely to be caused by an underlying condition such as enlarged lymph nodes, a tumor, or blood vessel abnormality in the intestines.

Diagnosis and Treatment

The doctor will perform a physical exam on the child, paying special attention to the abdomen. Sometimes the doctor can feel the part of the intestine that's involved, which is swollen and tender and often described as a "sausage-shaped mass."

Symptoms like repeated episodes of pain, drawing up the legs, vomiting, drowsiness, and passing stools with blood and mucous are meaningful in helping the doctor reach a diagnosis. The doctor also will ask take a medical history by asking parents about the child's symptoms and past health, the family's health, any medications the child is taking, any allergies the child has, and other issues.

If the doctor thinks intussusception may responsible, a pediatric surgeon will be consulted to examine the child and be available if surgery is required. The doctor might order an abdominal X-ray, which may or may not show a blockage in the intestines. An ultrasound also might be done to help make the diagnosis. If the child appears very ill, suggesting damage to the intestine, the surgeon may opt to take the child immediately to the operating room to correct the bowel obstruction.

A special kind of an enema that contains either air or barium is used to both diagnose and treat a suspected intussusception. During an air contrast enema, a small soft tube is placed in the rectum and air is passed through the tube. The air travels into the intestines and outlines the bowels on the X-rays. If intussusception is present it shows the doctors the telescoping piece in the intestine. At the same time, the pressure of the air unfolds the bowel that has been turned inside out and instantly cures the blockage. Barium is a liquid mixture that is used in place of air and works in the same way to fix the blockage.

The radiologist usually decides which test is most appropriate to perform. Both procedures are very safe and usually well tolerated by the child, although there is a very small risk of infection or bowel perforation (a hole in the intestines). There's a 10% risk of recurrence, which usually occurs within 72 hours following the procedure.

If the air or barium enema procedures aren't successful or the child is too ill to attempt the enema, the child will undergo surgery. Enemas are less successful in older children, who are more likely to require surgery to treat intussusception. Surgeons will try to fix the obstruction but if too much damage has been done, that part of the bowel will be removed.

After treatment, a baby will be kept in the hospital and given intravenous feedings until able to eat and have normal bowel function. Some babies may be given antibiotics to prevent infection.

Complications

If left untreated, intussusception can cause severe complications, which are directly related to the amount of time that passes from when the intussusception occurred until it's treated.

Most infants who are treated within the first 24 hours recover completely with no problems. Further delay increases the risk of complications, which include irreversible tissue damage, perforation of the bowel, infection, and death.

When to Call the Doctor

Intussusception is a medical emergency. If you're concerned that your child has some or all of the symptoms of intussusception, such as repeated crampy abdominal pain, vomiting, drowsiness, or passing of currant jelly stool, call your doctor or emergency medical services immediately.

The outcome for most infants with intussusception is very good, and with early treatment, complications are much less likely to develop.

Do not delay, though — in many cases, early diagnosis will mean a child can be successfully treated without surgery.

Reviewed by: Kate M. Cronan, MD
Date reviewed: January 2011
Originally reviewed by: Thom Lobe, MD