Primary biliary cholangitis (PBC) - formerly known as primary biliary cirrhosis - is a chronic, slowly progressive autoimmune liver disease. PBC mainly affects women (90%) and, typically, is diagnosed between the ages of 35 - 60. It is characterized by inflammation and destruction of small bile ducts, accompanied by fibrosis (excess fibrous connective tissue) and eventually cirrhosis (extensive scarring of the liver). Another key feature is the presence of specific anti-mitochondrial antibodies in the blood in over 90% of the patients.
Epidemiology
PBC is a relatively rare disease and occurs worldwide. The incidence and prevalence in various countries and regions differ considerably and have been reported to vary from 0.33 to 5.8 and and 1.91 to 40.2 cases per 100 000 inhabitants, respectively.
Symptoms
Many PBC patients do not experience any symptom at diagnosis or during the course of the disease and are diagnosed after the finding of abnormal liver tests at screening or testing for other conditions. However, a significant proportion of patients do have symptoms that can markedly influence the quality of life. The most common symptoms are fatigue and itching.
Treatment
Ursodeoxycholic acid (UDCA) is the standard treatment for PBC and is required to be life-long. This therapy is virtually free of adverse effects. UDCA has been proven to be effective at improving liver biochemistry markers, delaying histological progression, and improving liver transplant-free survival. Unfortunately, approximately 30-40% of patients have suboptimal response and would therefore be candidates for additional treatments as they are at continued risk for disease progression and complications of PBC. Patients without complete biochemical response to UDCA still benefit from UDCA, emphasizing its importance as first-line therapy for all patients with PBC. In 2016, obeticholic acid (OCA) obtained FDA approval and became the first available therapeutic agent for PBC since the introduction of UDCA with pruritus being a common side effect of OCA. Fibrates (bezafibrate and fenofibrate) have been also studied in PBC and have shown promising findings, in particular bezafibrate. Bezafibrate has been shown to improve liver biochemistry, hinder liver stiffness progression and improve pruritus and fatigue.