In what ways does cystic fibrosis affect the digestive system?

L.

Cystic fibrosis (CF) is an inherited disorder that affects the secretion of fluid and mucus by various organs in the body. This abnormality leads to malfunction of these organs and severe problems because of lung disease. Most patients are diagnosed in infancy or childhood, but it is not unusual for milder cases to be detected later in the teenage years.

As you mention, CF often affects the gastrointestinal tract. The most common effect is pancreatic disease. This is because of the abnormality in secretion of fluids from the pancreatic duct. The pancreas develops cysts and becomes scarred, leading to poor digestion and absorption of foods. As a result, diarrhea is a common symptom. In some cases, the diarrhea may not be apparent, but the child does not grow as expected according to growth charts. This is often a clue to the diagnosis.

Another digestive disorder associated with CF is meconium ileus. This condition, seen just after birth, refers to intestinal obstruction due to fetal stool (meconium). This blockage occurs because meconium is abnormally thick in infants with CF. Meconium ileus may require procedures, such as enemas, to loosen up the thick stool. Other causes of intestinal obstruction are also seen in CF patients later in life.

Patients with CF are also at risk of developing rectal prolapse. This is because of the large volumes of stool, combined with high abdominal pressure due to chronic coughing from lung disease. This may improve when the pancreatic dysfunction is treated with oral pancreatic enzyme therapy, leading to lower volume of stools. CF can also be complicated by liver disease such as fatty deposition and cirrhosis. This may be due in part to dysfunction in bile flow because of the problems with fluid secretion mentioned. Finally, gallstones and gallstone complications are more frequently seen with CF.