Select from the menu above to compare the normal bile flow to the bile flow with CF. Normal: Bile flow of the liver into the small intestine aids digestion. With CF: Thick bile in CF patients blocks the bile ducts in the liver.

Abnormal Function
CF affects the liver and gallbladder, resulting in abnormal bile production. This bile is dehydrated and more acidic than normal bile, reducing its flow into the small intestine. Because the acidic contents can not be neutralized, the lining of the small intestine may be damaged. Dehydrated bile can concentrate in the gallbladder---producing gallstones---which can cause cholecystitis, an inflammation of the gallbladder marked by pain, fevers, nausea, and vomiting. When this occurs, surgical removal of the gallbladder may be required. Occasionally, gallstones can obstruct the ducts of the pancreas and cause pancreatitis. Mucus obstructed bile ducts in the liver can also impair absorption of nutrients, and lead to liver damage. The result may be hepatic  steatosis, or “fatty liver,” characterized by accumulation of fats in the liver, found in up to 60 percent of CF patients.

Cirrhosis and Portal Hypertension
About five percent of adult CF patients suffer cirrhosis of the liver, a serious complication caused by the formation of dense fibrous tissue and resulting in the destruction of liver cells. Focal biliary cirrhosis is caused by plugging of liver bile ducts by dehydrated mucus and bile. This obstruction leads to inflammation and eventually fibrosis of the ducts, further impairing the release of bile and overall liver function. Eventually, several areas of the liver may be affected. 

Repeated scarring and fibrosis of the ducts affects liver blood flow, a condition known as portal hypertension. Unable to accommodate the increased volume, blood is redirected to other blood vessels. Consequently, these vessels become engorged, dilated, and prone to life-threatening bleeding. As portal hypertension worsens, blood supply to the liver is compromised, leading to liver failure. Then, toxic substances normally removed by the liver remain in the bloodstream, causing confusion, coma, and eventually death.

Physical examination of the liver and spleen should be performed at each clinic visit. Yearly liver function tests should be obtained, including tests for causes of elevated liver enzymes, such as drugs, toxins, and infections.  Radiographic tests can identify mechanical obstruction of the liver ducts or gallbladder, changes of the liver suggesting cirrhosis, and fatty changes suggesting steatosis. Therapy for liver disease should include nutritional support, preventive interventions, and management of complications.

Severe CF liver disease can lead to cirrhosis or scarring in the liver. The liver enlarges and there is increased blood pressure in the liver that causes the spleen to enlarge as well.