Primary biliary cholangitis (PBC) is a rare but serious and severely limiting autoimmune liver disease. Diagnosis of PBC is complicated by the different diagnostic performance of different autoantibodies in different populations.

There are limited data on the performance of autoantibodies for PBC diagnosis among Hispanic/Latino populations.

To assess the diagnostic performance of anti-mitochondrial antibodies (AMAs), anti-nuclear antibodies (ANAs), anti-smooth muscle antibodies (ASMAs), plasma immunoglobulin (Ig) M and plasma IgG for the diagnosis of histologically-confirmed PBC among female Colombian patients.

We studied 43 PBC cases and 42 controls in whom PBC was ruled out. All antibodies were measured using immunofluorescence or enzyme-linked immunosorbent assay within 1 year of the index biopsy. A sensitivity analysis was performed using pathology + elevated alkaline phosphatase to define case-control status. Patients with viral or alcoholic hepatitis were excluded.

The sensitivity of ANA was only 44.2%, specificity was 76.2%. No individual antibody or antibody combination displayed an acceptable combination of sensitivity and specificity, but the combination of positive AMA and positive ASMA had a very high specificity. IgM had particularly high specificity and positive predictive value.

We found a remarkably high prevalence of AMA-negative PBC among female Colombian patients. IgM served not only as a marker of PBC, but also as a marker of liver fibrosis.

It is urgent to find a good marker for AMA-negative PBC, especially for Hispanic/Latino populations.