General information
After birth, a newborn baby should wean off meconium within the first 24-48 hours. Meconium is the first bowel movement of the newborn and is also known in common parlance as child-spittle because of its black-greenish color. Meconium does not actually represent a proper bowel movement, but is a waste product of dead epithelial cells, bile, and swallowed hair and skin cells that have accumulated in the functionless intestine during pregnancy.
In the quite rare case of a meconium ileus, the newborn child’s intestinal obstruction is caused by thickened and putty-like meconium, which clogs and sticks together the intestine. A meconium ileus occurs mainly in patients with cystic fibrosis (cystic fibrosis), but can also occur in other diseases of the newborn. A very similar clinical picture is the meconium grafting syndrome (or pseudomeconium ileus), but newborns with a meconium graft syndrome are healthy in the majority of cases.
Symptoms
Newborns affected by a meconium ileus are conspicuous by a lack of meconium. Since the newborn’s intestine is blocked by the meconium, but the newborn now begins to produce proper bowel movements due to the feeding of breast milk, the abdomen becomes increasingly distended by the accumulation of stool and air. A common symptom is vomiting of the food supplied, as it can no longer be absorbed and processed by the already congested intestine.
A complication of the meconium ileus is a perforation of the intestine, which virtually “bursts” under the pressure of the meconium. As a result, a dangerous meconium peritonitis develops, which is manifested by fever, a distended and reddened abdomen (belly) and sudden severe illness of the newborn. A perforated meconium ileus must always be treated surgically
Causes
Almost 10% of newborns with cystic fibrosis (cystic fibrosis) have a meconium ileus after birth, but 90% of newborns with meconium ileus have cystic fibrosis. Cystic Fibrosis is therefore the most common cause of a meconium ileus. In cystic fibrosis, an autosomal recessive genetic mutation on chromosome 7 causes the malfunction of the CFTR chloride transporter.
Due to this malfunction, the secretion of chloride is disturbed in most organs (e.g. lung, intestine, pancreas), which leads to a thickening of these secretions. Hirschsprung’s disease is another cause: In this disease, which is also called congenital aganglionosis, there is no supply of nerve cells to the colon over a variable distance from the anus. Due to the lack of innervation of the last section of the intestine, this section is dysfunctional and cannot transport the meconium, which leads to the meconium ileus.
The hypoplasia of the left colon (large intestine) is another common cause of a meconium ileus and describes a functional disorder of the last section of the large intestine, which can be completely cured by repeated enemas of contrast medium. In favorable cases, a problem-free intestinal passage is possible after four to six months. In 50% of the cases the hypoplasia of the left colon is associated with a (gestational) diabetes of the mother.
Rare causes of a meconium ileus are atresia (congenital obstruction) of the intestine, which can occur at any height. An underfunction of the thyroid gland of the newborn can also lead to a meconium ileus due to the missing or insufficient impulse of thyroid hormones on the control of intestinal function. An important differential diagnosis of real meconium ileus is the so-called meconium graft syndrome, which can occur in newborns with only low intestinal motility (intestinal movement) and relatively late food intake.
In the affected newborns, the intestine is simply still too sluggish to transport the meconium and the late intake of food also stimulates activity late in life. Most newborns with a meconium graft syndrome are completely healthy, but should still be examined for serious diseases such as Hirschsprung’s disease or cystic fibrosis. If the mother has received magnesium sulfate (in laxatives) or opiates (strong painkillers) during pregnancy, this can lead to a delayed release of meconium.
Cystic fibrosis is a genetic disease. It is characterized by a reduced secretion of individual glands. Due to the dysfunction, the secretions in the intestine are much tougher and slimier than in healthy people.The meconium becomes viscous and sticky. Cystic fibrosis is the most common cause of a meconium ileus and should always be clarified when diagnosing an ileus.
