Evaluation of patients with positive anti-mitochondiral antibody and normal alkaline phosphatase levels for primary biliary cholangitis

Primary Biliary Cholangitis (PBC) is a chronic cholestatic liver disease typically diagnosed by elevated cholestatic liver enzymes and a positive anti-mitochondrial antibody (AMA) test. The clinical importance of AMA positivity in patients with normal cholestatic liver enzymes is unclear. The aim of this study was to determine the relationship between PBC and AMA positivity detected in individuals with normal cholestatic enzyme levels. The files of patients with AMA and/or AMA-M2 positivity between 2009 and 2018 and whose alkaline phosphatase (ALP) levels were below upper limit of normal (ULN) at initial admission were retrospectively analyzed. The ALP levels were normal in all patients. All patients had AMA positivity demonstrated by indirect immunofluorescence (IIF) or AMA-M2 positivity demonstrated by ELISA. A total of 16 patients underwent liver biopsy and seven (43.75%) showed changes consistent with those with PBC. A total of 12 patients were diagnosed with PBC and were treated and followed up with this diagnosis. People with AMA positivity and normal cholestasis enzyme levels are closely associated with PBC. Some of these patients were diagnosed with PBC as a result of biopsy and some were diagnosed by clinical and laboratory findings during follow-up.. The patients with an AMA titration of 1/20 were not associated with PBC. In our study, results similar to the studies confirmed by biopsies were obtained. In this regard, there is a need for prospective and retrospective studies with longer follow-up periods.

Keywords: primary biliary cholangitis, alkaline phosphatase.