Today’s lecture focused on the diagnosis of primary biliary cirrhosis (PBC), a non-supperative inflammatory condition of the small caliber bile ducts. It is thought to be caused by a genetic predisposition, followed by an environmental insult. No pathogen has been indicted thus far; some studies suggest that proximity to a federal waste dumping site has an association.
There were many interesting insights provided. In many cases, PBC is preceeded by a positive AMA; the patient will be asymptomatic and have normal LFT. There is no stellar evidence to recommend treatment at this subclinical stage, but if histologic activity can be proven, ursodiol at 12-15 mg/kg is indicated. Additionally, first degree female relatives should be screened for PBC with an AMA, as up to 20% will have the diagnosis.
There was much discussion about treatment protocol. Colchicine 0.6mg BID is a second line agent that can be started if the alkaline phosphatase does not normalize over the course of 9-12 months. Remember that colchicine is notorious for causing GI side effects. Typically, ursodiol and chochicine are enough to prevent progression to liver failure. However, if the bilirubin rises above 3, this is a sign that the liver will likely progress to liver failure, and transplantation evaluation is indicated.
As a rescue therapy, methotrexate (MTX) was recommended. Methotrexate has well known side effects, from bone marrow toxicity, hepatotoxicity and pneumonitis, but the presenter of this lecture shared a very benign track record with this drug and refractory PBC. It should only be considered, in my opinion, when the stage of disease is advanced, and particularly when MTX has a second indication like another rheumatologic disease.