Liver

Liver disease is the third leading cause of death among people with cystic fibrosis (CF) and there is a wide spectrum of liver disease among people with CF. However, only 5-10 percent of people with CF develop severe liver disease that may significantly impact their life outcomes.

The liver has many roles. It is used to break down fats, to store glycogen, to render defunct blood cells and to ‘clean’ the circulatory system. 

The liver breaks down and processes medications (e.g. antibiotics) ingested by an individual. It also produces digestive bile that is crucial for the digestion of certain foods.

The genetic defect that causes CF leads to problems with the drainage of bile out of the liver via the bile ducts and gallbladder. Scarring of the liver (fibrosis) can develop, and in severe cases, this can lead to cirrhosis.

If the cirrhosis progresses it can adversely affect functioning of the liver as well as cause increased pressure in the blood vessel flowing into the liver leading to the development of enlarged blood vessels (varices) and splenic enlargement. This is known as portal hypertension and can be linked with risk of bleeding from the gut. In some people with CF, liver transplantation may be required.

Adults with CF may also be at risk of developing cancer affecting the bile ducts (cholangiocarcinoma). Some cases have been reported, however the evidence that its prevalence in people with CF is greater than the general population is currently weak. 

Unfortunately, no screening guidelines are currently available.

There is currently no evidence-based medication that prevents or treats liver disease in CF. Ursodeoxycholic acid (UDCA), a bile acid that helps the body digest fats, is a commonly used therapy but evidence to support its benefit has been unconvincing. 

To minimise and avoid other potential forms of liver disease, it is recommended to minimise alcohol intake and ensure your immunisation status is up to date.

The role and impact of CFTR modulators on liver disease in CF is currently being investigated.