enhanced monosomy X in female patients and an enhanced Y chromosome loss in male patients, have been described and might well explain the greater female predisposition to develop PBC.An association of a greater incidence of PBC at latitudes more distant from the Equator is similar to the pattern seen in multiple sclerosis.Typical disease onset is between 30 and 60 years, though cases have been reported of patients diagnosed at the ages of 15 and 93. Prevalence of PBC in women over the age of 45 years could exceed one in an estimated 800 individuals. History
The first report of the disease dates back 1851 by Addison and Gull, who described a clinical picture of progressive jaundice in the absence of mechanical obstruction of the large bile ducts. Ahrens et al. in 1950 published the first detailed description of 17 patients with this condition, and coined the term "primary biliary cirrhosis". In 1959, Dame Sheila Sherlock reported a further series of PBC patients and recognised that the disease could be diagnosed in a precirrhotic stage and proposed the term "chronic intrahepatic cholestasis" as more appropriate description of this disease, but this nomenclature failed to gain acceptance, and the term "primary biliary cirrhosis" lasted for decades. In 2014, to correct the inaccuracy and remove the social stigmata of cirrhosis, as well as all the misunderstanding, disadvantages, and discrimination emanating from this misnomer in daily life for patients, international liver associations agreed to rename the disease "primary biliary cholangitis", as it is now known.
Liver chemistries usually improve within a few weeks of starting UDCA, and 90% of any benefit is observed after 6–9 months of therapy. Liver chemistries should be re-evaluated after 1 year of treatment. UDCA is usually continued lifelong. Up to 40% of people do not respond to treatment with UDCA. Patients with PBC who have an inadequate response to UDCA or those few (less than 3%) who are intolerant to UDCA are candidates for second-line therapies. Obeticholic acid (OCA) is FDA-approved for the treatment of PBC in individuals intolerant or unresponsive to UDCA. OCA is a farnesoid X receptor  agonist, and results in increased bile flow (choleresis). OCA is started at 5 mg daily, and liver chemistries should be rechecked after 3 months of treatment. If the liver chemistries remain elevated, then the dose of OCA may be increased to 10 mg per day. The most common side effect of OCA is pruritus. Fibric acid derivatives, or fibrates, are agonists of the peroxisome proliferator activator receptor (PPAR), a nuclear receptor involved in several metabolic pathways. While fibrates are approved for the treatment of hypertriglyceridemia, they exert anticholestatic effects and have been studied for the treatment of PBC. Among the fibrates, bezafibrate and fenofibrate, PPAR-alpha selective agonists, have been extensively studied as therapeutic agents because of their potential ability to decrease bile acid synthesis and bile acid-related hepatic inflammation. A randomized, controlled trial in 2018 showed its efficacy in patients with inadequate response to UDCA.