Cystic Fibrosis and the Digestive System
How does CF affect the digestive system?
Children with cystic fibrosis (CF) have a protein in their cells that doesn't work
right. The protein is called CFTR (the cystic fibrosis transmembrane regulator). CFTR
controls the flow of water and certain salts in and out of the body's cells. As the
movement of salt and water in and out of cells changes, mucus becomes thickened.
In the digestive system, CF mainly affects the pancreas. The pancreas is an organ
that puts out (secretes) certain substances. They help with digestion and control
the body's blood sugar levels.
The abnormality in CFTR makes the pancreas secretions become thick. The thickened
secretions can block the ducts in the pancreas. This blockage causes a drop in the
amount of digestive enzymes the pancreas puts out. Because of this, a child with CF
has trouble absorbing fats, some proteins, and fat-soluble vitamins A, D, E, and K.
The problems with the pancreas can get very severe. Some of the hormone cells in the
pancreas can be destroyed. This may lead to glucose intolerance and type 1 diabetes.
About 35 out of 100 people with CF get CF-related diabetes in their 20s. And more
than 40 out of 100 people with CF get CF-related diabetes after age 30.
Because of CF's effects on the digestive system, a child with CF may have these symptoms:
Frequent, bulky, greasy stools
A rare condition where the end part of the bowels comes out of the anus (rectal prolapse)
A bowel blockage caused by a baby's thick and sticky first bowel movement (meconium
Fat in the stools
Poor weight gain and growth
The child may also have bloating, flatulence, belly pain, and watery diarrhea caused
by too much bacteria.
The liver may also be affected. A small number of children may actually develop liver
disease. Symptoms of liver disease may include: