How does CF affect the digestive
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 ileus)
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: