Primary biliary cholangitis is an autoimmune disease of the liver , caused by a defect in the immune system, whereby T lymphocytes attack the cells of the small bile ducts, a dense network of canaliculi located inside the liver that continuously transports the bile produced (through the small bile ducts, the bile reaches the intestine where it carries out its function in the digestion of fats and some vitamins and in the elimination of some toxic products in the feces).
Primary biliary cholangitis (PBC) is more common in women and, if left untreated, can progress to cirrhosis of the liver and cause irreversible damage to the organ.
Professor Ana Lleo De Nalda , hepatologist at the Humanitas Medical Care Premuda clinic in Milan and head of the Center for Autoimmune Liver Diseases at the IRCCS Istituto Clinico Humanitas in Rozzano, talks to us about it.
What causes primary biliary cholangitis?
Many studies in recent years have investigated the cause of the disease. To date, however, a single causative agent has not yet been identified. Available data show that some genetic factors, such as female sex, as well as some environmental factors, such as previous infections, may play a role in triggering PBC.
Primary biliary cholangitis: what are the symptoms?
Initially, primary biliary cholangitis may present no symptoms and patients are diagnosed only after an abnormal test result.
However, a significant number of patients experience insidious symptoms, such as:
· itching
· tiredness
· dry mouth or eyes
Symptoms attributable to liver failure tend to appear only when the inflammation becomes more aggressive and the liver is irreversibly damaged, and are characterised by:
· jaundice of both the skin and the sclera
· swelling of ankles and feet
· accumulation of fluid in the abdomen
· fatty deposits in the skin, especially around the eyes and eyelids, and on the hands, feet, elbows, and knees.
What consequences can primary biliary cholangitis have?
In addition to liver cirrhosis, the main consequences of this disease are: portal hypertension and, in the worst cases, liver cancer.
How is primary biliary cholangitis diagnosed?
Primary biliary cholangitis is diagnosed through blood tests that evaluate liver function and the presence of specific antibodies , such as anti-mitochondrial antibodies (often also associated with an increase in IgM concentrations), or some rare types of antinuclear antibodies.
Other in-depth tests are:
· abdominal ultrasound
· elastography (performed using an ultrasound probe similar to the one used for ultrasound).
In specific cases, especially in patients with negative autoantibodies, a liver biopsy may be necessary. In advanced cases, an abdominal CT scan with contrast may also be necessary.
How can primary biliary cholangitis be treated?
The first-line treatment for primary biliary cirrhosis is ursodeoxycholic acid at a dose of 13–15 mg/kg/day . For patients who do not respond to treatment after 12 months, a second-line therapy is available: obeticholic acid . Other drugs, such as fibrates, can also be used in patients with pruritus. To evaluate the effectiveness of the therapy, we use biochemical parameters (alkaline phosphatase levels), which are easy to obtain and non-invasive (a blood test is sufficient).
The data at our disposal clearly demonstrate that early diagnosis, timely therapy at appropriate dosages, and normal alkaline phosphatase values are associated with an excellent prognosis.
In rare severe cases where the liver disease is decompensated and there are particularly high bilirubin values, a liver transplant may be proposed .
To relieve symptoms, such as itching or vitamin deficiency, a number of medications and supplements are available. It’s very important to assess bone health with a bone mineral density scan and targeted blood tests because osteoporosis is common in patients with PBC .
Can primary biliary cholangitis be prevented?
Primary biliary cholangitis is a disease that cannot be prevented. However, it is important to limit the onset of other liver diseases (the most common being steatohepatitis) by leading a balanced lifestyle, including a healthy diet rich in whole grains, fruits, and vegetables, and low in salt, fat, and alcohol (the latter should be completely eliminated if diagnosed), and engaging in regular physical activity.
