Overcoming a “Probable” Diagnosis in Antimitochondrial Antibody Negative Primary Biliary Cirrhosis: Study of 100 Sera and Review of the Literature

Serum anti-mitochondrial antibodies (AMA) are the serological hallmark of primary biliary cirrhosis (PBC), yet up to 15% of PBC sera are AMA negative at routine indirect immunofluorescence (IIF) while being referred to as “probable” cases. The diagnostic role of PBC-specific antinuclear antibodies (ANA) remains to be determined. We will report herein data on the accuracy of new laboratory tools for AMA and PBC-specific ANA in a large series of PBC sera that were AMA-negative at IIF. We will also provide a discussion of the history and current status of AMA detection methods. We included IIF AMA-negative PBC sera (n = 100) and sera from patients with other chronic liver diseases (n = 104) th…