Clinical characteristics of antimitochondrial antibody-positive patients at a safety net health care system in Arizona

Abstract

Background and aimsTo assess whether aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (AP) levels can predict the diagnosis of primary biliary cholangitis (PBC) or any other diagnoses and whether PBC occurs either simultaneously or independently of other liver diseases among antimitochondrial antibody (AMA)-positive patients.MethodsDemographic and clinical variables were assessed in 90 AMA-positive patients with and without liver biopsies. These patients were further categorised as having a diagnosis of PBC, overlap syndrome or ‘not established with a diagnosis of PBC’. Receiver operating characteristic curves were constructed to determine the thresholds of liver enzymes that predict these three diagnoses.ResultsThe 48 patients with liver biopsies were more frequently female and had significantly higher AP levels compared with the non-liver biopsy group. Based on liver biopsy findings, 12, 12 and 22 patients were assigned a diagnosis of PBC, overlap syndrome with autoimmune hepatitis and PBC and ‘not established diagnosis of PBC’, respectively. Seven of 12 patients classified as PBC had AP level of ˂200 IU. AST, ALT and AP levels were significant predictors of a diagnosis of overlap syndrome compared with the rest of the patients; however, these tests were not discriminatory between diagnoses of PBC and ‘not established with PBC’. Findings of fatty liver and bile duct injury on liver biopsies were not significantly associated with any liver test pattern.ConclusionsAs the liver test pattern did not correlate with the liver biopsy findings of PBC or other non-PBC diagnoses in AMA-positive patients at risk for other disease, a liver biopsy and/or non-invasive liver assessment along with serum liver tests should be interpreted to complete liver evaluation.

Evaluation of classical and novel autoantibodies for the diagnosis of Primary Biliary Cholangitis-Autoimmune Hepatitis Overlap Syndrome (PBC-AIH OS)

“…The presence of elevated ALT is suggestive of underlying hepatocellular injury and IgG is an indicator of predominant plasma cell infiltration of the liver; both characteristic of AIH [ 39 , 40 ]. Our findings of elevated ALT as a predictor of PBC-AIH OS are congruent with findings from a recent study [ 41 ]. However, unlike this study, we did not identify AP, AST, or total bilirubin as being predictive of PBC-AIH OS.…”

Poor performance of anti-mitochondrial antibodies for the diagnosis of primary biliary cholangitis in female Colombian patients: A single-center study

“…Even though AMA are the antibodies classically related to PBC, there is evidence that most patients with positive AMA do not have PBC findings in liver biopsy[ 26 , 27 ]. More than half of PBC cases in our sample were AMA-negative, much higher than in prior reports (5%-18%)[ 28 ].…”