About Intestinal Malrotation

An intestinal obstruction is a blockage of the digestive tract that prevents the proper passage of food. Some intestinal obstructions are present at birth, while others are caused by such problems as hernias, abnormal scar tissue growth after an abdominal operation, and inflammatory bowel disease (IBD).

Malrotation is twisting of the intestines (or bowel) caused by abnormal development while a fetus is in utero, and can cause obstruction. Malrotation occurs in 1 out of every 500 births in the United States.

Some children with intestinal malrotation are born with other associated conditions, including:

• other defects of the digestive system
• heart defects
• abnormalities of other organs, including the spleen or liver

Some kids with malrotation never experience complications and are never diagnosed. But most develop symptoms during infancy, and the majority are diagnosed by 1 year of age. Although surgery is required to repair malrotation, most kids will go on to grow and develop normally after treatment.

How It Can Happen

The small and large intestines are the longest part of the digestive system. If stretched out to their full length, they would measure more than 20 feet long by adulthood, but because they're folded up, they fit into the relatively small space inside the abdomen.

Malrotation occurs when the intestines don't position themselves normally during fetal development and aren't attached inside properly as a result. The exact reason this occurs is unknown.

When a fetus develops in the womb, the intestines start out as a small, straight tube between the stomach and the rectum. As this tube develops into separate organs, the intestines move into the umbilical cord, which supplies nutrients to the developing embryo.

Around the 10th week of pregnancy, the intestines move from the umbilical cord into the abdomen. When they don't properly turn after moving into the abdomen, malrotation occurs.

Malrotation in itself may not cause any problems. However, it can lead to other complications:

• Bands of tissue called Ladd's bands may form, obstructing the first part of the small intestine (the duodenum).
• In a condition called volvulus, the bowel twists on itself, cutting off the blood flow to the tissue and causing the tissue to die. The symptoms associated with volvulus, including pain and cramping, are often what lead to the diagnosis of malrotation.
• Obstruction caused by volvulus or Ladd's bands is a potentially life-threatening problem. The bowel can stop functioning and intestinal tissue can die from lack of blood supply if an obstruction isn't recognized and treated. Volvulus, especially, is an emergency situation, with the entire small intestine in jeopardy.

Signs and Symptoms

One of the earliest signs of malrotation and volvulus is abdominal pain and cramping caused by the inability of the bowel to push food past the obstruction. When infants experience this cramping they may:

• pull up their legs and cry
• stop crying suddenly
• behave normally for 15 to 30 minutes
• repeat this behavior when the next cramp happens

Infants also may be irritable, lethargic, or have irregular stools.

Vomiting is another symptom of malrotation, and it can help the doctor determine where the obstruction is located. Vomiting that happens soon after the baby starts to cry often means the obstruction is in the small intestine; delayed vomiting usually means the blockage is in the large intestine. The vomit may contain bile (which is yellow or green in color) or may resemble feces.

Additional symptoms of malrotation and volvulus may include:

• a swollen abdomen that's tender to the touch
• diarrhea and/or bloody stools (or sometimes no stools at all)
• irritability or crying in pain, with nothing seeming to help
• rapid heart rate and breathing
• little or no urine because of fluid loss
• fever

Diagnosis

If volvulus or another intestinal blockage is suspected, the doctor will examine your child and then may order X-rays, a computed tomography (CT) scan, or an ultrasound of the abdominal area.

The doctor may use barium or another liquid contrast agent to see the X-ray or scan more clearly. The contrast can show if the bowel has a malformation and can usually determine where a blockage is located.

Adults and older kids usually drink barium in a liquid form. Infants may need to be given barium through a tube inserted from the nose into the stomach, or sometimes are given a barium enema, in which the liquid barium is inserted through the rectum.

Treatment

Treating significant malrotation almost always requires surgery. The timing and urgency will depend on the child's condition. If there is already a volvulus, surgery must be performed right away in order to prevent damage to the bowel.

Any child with bowel obstruction will need to be hospitalized. A tube called a nasogastric (NG) tube is usually inserted through the nose and down into the stomach to remove the contents of the stomach and upper intestines. This keeps fluid and gas from building up in the abdomen. The child may also be given intravenous (IV) fluids to help prevent dehydration and antibiotics to prevent infection.

During the surgery, which is called a Ladd procedure, the intestine is straightened out, the Ladd's bands are divided, the small intestine is folded into the right side of the abdomen, and the colon is placed on the left side.

Because the appendix is usually found on the left side of the abdomen when there is malrotation (normally, the appendix is found on the right), it is removed. Otherwise, should the child ever develop appendicitis, it could complicate diagnosis and treatment.

If it appears that blood may still not be flowing properly to the intestines, the doctor may perform a second surgery within 48 hours of the first. If the bowel still looks unhealthy at this time, the damaged portion may be removed.

If the child is seriously ill at the time of surgery, an ileostomy or colostomy will usually be performed. In this procedure, the diseased bowel is completely removed, and the end of the normal, healthy intestine is brought out through an opening on the skin of the abdomen (called a stoma). Fecal matter passes through this opening and into a bag that is taped or attached with adhesive to the child's belly.

In young children, depending on how much bowel was removed, the ileostomy or colostomy is often a temporary condition that can later be reversed with another operation.

The majority of these surgeries are successful, although some kids have recurring problems after surgery. Recurrent volvulus is rare, but a second bowel obstruction due to adhesions (scar tissue build-up after any type of abdominal surgery) could occur later.

Children who require removal of a large portion of the small intestine can have too little bowel to maintain adequate nutrition (a condition known as short bowel syndrome). They may be dependent on intravenous nutrition for a time after surgery (or even permanently if too little intestine remains) and may require a special diet afterward.

Most kids in whom the volvulus and malrotation are identified early, before permanent injury to the bowel has occurred, do well and develop normally.

If you suspect any kind of intestinal obstruction because your child has bilious (yellow or green) vomiting, a swollen abdomen, or bloody stools, call your doctor immediately, and take your child to the emergency room right away.

Reviewed by: J. Fernando del Rosario, MD
Date reviewed: February 2011