What is meconium ileus?
Meconium ileus, a serious condition in newborn babies in which the intestines are blocked by the infant’s first stool, often needs surgical intervention and usually indicates the child will struggle with the congenital disease cystic fibrosis throughout their lives.
Meconium ileus is intestinal obstruction caused by thick, congealed meconium (baby’s first stool), which does not get evacuated after the birth of a baby.
Cystic fibrosis is an inherited disorder caused by a genetic mutation which causes thickening of the mucus and primarily affects the respiratory tract and pancreatic function. Cystic fibrosis leads to hardening of meconium and prevents its evacuation.
Meconium ileus may be:
- Simple meconium ileus: Simple obstruction in the small intestines resulting in dilatation of the bowel above the obstruction, and bowel wall thickening.
- Complicated meconium ileus: Intestinal obstruction complicated by conditions such as intestinal twisting, perforation and infection.
How is meconium ileus treated?
If the newborn has abdominal distension or other symptoms of meconium ileus, the initial medical treatment involves:
- Initiation of resuscitation of the infant
- Administration of IV fluids
- Gastric decompression by removing the gas in the digestive tract
- Administration of antibiotics
- Imaging test to evaluate the cause for abdominal distension
- Meglumine diatrizoate enema
A diagnosis of a simple meconium ileus is most often treated with an enema, though some infants may require surgery. The administration of enema involves the following steps:
- Prepare the infant with adequate hydration, supplemental electrolytes and antibiotics.
- Administer enema with meglumine diatrizoate (Gastrografin), a water- soluble substance that softens the meconium, and also acts as a contrast medium for continuous X-ray (fluoroscopy) to monitor the process.
- Continue hydration with IV fluids.
- Monitor the baby closely for the next few hours.
- Administer additional enemas if required, until the meconium is completely evacuated.
- Imaging tests to confirm complete evacuation of the meconium.
- Administer supplemental pancreatic enzymes after obstruction is cleared, usually within 48 hours, if the baby is diagnosed with cystic fibrosis.
Potential complications of Gastrografin include:
- Perforation of the bowel
- Hypovolemic shock (shock from loss of fluids, which must be carefully monitored and managed with supplemental IV fluids)
- Ischemia (reduced blood supply to the tissues)
When is surgery indicated for meconium ileus?
Surgical treatment is indicated if the newborn has complicated meconium ileus, with one or more of the following conditions:
- Persistent abdominal distension
- Enlarging abdominal mass
- Volvulus (twisting of a loop of intestine)
- Atresia (malformation of intestine)
- Necrosis (tissue death)
- Perforation
- Meconium peritonitis (inflammation of peritoneum, the abdominal membrane) and pseudocyst formation from the spillage of meconium through the perforation
What are the surgical treatments for meconium ileus?
Surgical treatments for meconium ileus are individualized for each infant. A pediatric surgeon performs the surgery with the baby under general anesthesia.
Preparation
Prior to a surgical procedure
- The infant undergoes imaging tests
- The neonatal care team
- Administers IV fluids and antibiotics
- Performs gastric decompression
Procedure
The surgical treatments for meconium ileus may involve one or more of the following procedures:
- Enterostomy: A procedure to make one or more openings (stomas) in the abdomen to insert small tubes into the intestine. The tubes are used to irrigate, decompress the bowel, and also for feeding. The tubes are removed once the obstruction is completely cleared.
- Resection: Removal of the affected portion of the intestine.
- Anastomosis: Anastomosis is a procedure to connect the severed ends of the bowel after a resection.
- Transplantation: Intestinal and/or liver transplantation because of cystic fibrosis associated liver damage.
Post-procedure
After surgery, the baby’s hydration and electrolyte requirements are managed carefully. Infants who have surgery for simple meconium ileus with cystic fibrosis may receive breast milk or formula milk, pancreatic enzymes and vitamins.
Babies who have a complex surgical procedure for complicated meconium ileus may receive diluted, pre-digested infant formula through the tube, until they are able to feed orally. Pancreatic enzymes are administered orally after the baby starts oral feeding.
Complications
In addition to surgical risks such as wound infection and bleeding, complications from surgical procedures for meconium ileus include the following:
- Excessive fluid and sodium loss in infants who undergo removal of a significant portion of the intestines.
- Adverse effects on the development of the colon and the growth of beneficial bacteria in the colon below the stoma, which is nonfunctional until the enterostomy tubes are removed.
- Excessive gastric acid in the shortened intestines can cause malabsorption of nutrients (short bowel syndrome).