Cystic fibrosis (CF) is most commonly thought of as a respiratory condition. But it affects more than just the lungs. It can cause functional problems for the reproductive and digestive systems and different organs including the liver, pancreas and gallbladder.1-3 Liver involvement is common, occurring in 30 to 50 percent of those with cystic fibrosis.4
CF is an inherited disease. It is characterized by problems in the body's salt and water balance in certain cells that cause a broad range of symptoms.3 Common ones include problems gaining weight, fatigue, nausea and other abdominal issues, gastrointestinal track bleeding, jaundice and pruritus (itching).2
Cystic fibrosis liver disease
There are many different kinds of liver disease that can develop in people with CF.1 The conditions can range from steatosis, an abnormal retention of fat (lipids) within a cell or organ and neonatal cholestasis, decreased bile formation and/or excretion in newborns, to cholelithiasis (gallstones) and cirrhosis (scarring).1 They are often referred to as cystic fibrosis-associated liver disease (CFLD).1
Liver problems are common issues that develop in CF. Many children with cystic fibrosis develop liver problems as they grow older.3 However, the reason liver problems develop – the pathophysiology - is not fully understood.1,2 Researchers think it may be related to errors in the CFTR protein which affects the movement of salt and water in and out of cells. When there is not enough fluid, the different secretions, like bile and mucus thicken.
When CF involves the liver and bile ducts there are often no symptoms. This is sometimes called “clinically silent”.1 But liver disease is the third leading cause of death among people with CF.1,2 Unfortunately, there is no available test to identify liver disease. However, there are some predictive factors that have been identified. These include age at the time of CF diagnosis, being male, having a history of bowel obstruction (meconium ileus) or digestive problems due to functional defects in the pancreas.2
What happens to the liver?
Bile produced by the liver gets stickier than normal in people with CF and can block small bile ducts. This damages and scars liver tissue. As the liver tries to heal itself, scar tissue continues to form, and makes it hard for the liver to function properly.3,5
An early diagnosis of cystic fibrosis liver disease is important because once clinical symptoms are present there is generally extensive and irreversible liver damage already.5 Therefore, screening for the detection of liver involvement in cystic fibrosis is essential if treatment has any chance at being effective.1
CFLD diagnosis
Clinical guidelines from the Cystic Fibrosis Foundation suggest the following tools for the screening and diagnosis of CFLD.1,2 They include a combination of clinical lab and imaging tests.5
- Regular clinical exam to check for physical symptoms in the liver and spleen
- Biochemical evaluation to look at liver enzyme activity
- Annual panel of liver blood tests
- Radiographic imaging including ultrasound
- Upper gastrointestinal endoscopy
CF-related cirrhosis
5-10 percent of people with CF will develop CF-related cirrhosis. It commonly develops in childhood, the median age at diagnosis is 10 years old.1 When the liver hardens from the scarring, and blood flow through the liver gets slower, pressure increases in the vein leading to the liver. This is called portal hypertension, and it can be identified by ultrasound.1,5 Other symptoms of CF cirrhosis include jaundice, blood clotting disorders, and abdominal swelling (ascites).2
No treatments are currently available to prevent CF cirrhosis or to slow its progression. Cirrhosis is considered a final and irreversible stage of liver disease and can lead to liver failure.2
Treatment for cystic fibrosis liver disease
Treating for CF liver disease will likely include a team of medical professionals including a pediatric or adult hepatologist (liver specialist), pulmonologist, a radiologist, dietician and possibly others depending on each patient’s needs.1
CFLD is often an early complication of cystic fibrosis. Therefore, doctors should check carefully for the presence of symptoms in the early years of the disease. A CF appropriate diet including fat-soluble vitamins can be helpful. Your healthcare team or nutritionist can help design a good food plan that considers any specific nutritional needs or dietary restrictions.1 Additionally, regular clinical management and medications along with nutritional changes can help to minimize other medical issues that can develop with CF liver disease.3