Clinical characteristics to identify the etiological diagnosis of hepatic injury in patients with alanine aminotransferase activities over 15 times the upper reference limit

Objective To investigate distinguishing clinical features that may be useful for etiological diagnosis of hepatic injury, including changes in alanine aminotransferase (ALT) and immunological markers of viral infection. Methods Seventy patients with initial baseline ALT that was greater than 15 times the upper limit of normal (15×ULN) were recruited to the study between January 2011 and December 2011.Hepatic function markers (bilirubin, ALT, prothrombin time, and alkaline phosphatase) were measured by standard biochemical assays and immunological markers of hepatitis virus [hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) and HEV and HBV DNA] were examined by immunoassays and quantitative PCR.Changes in ALT over several weeks were statistically analyzed for correlation with laboratory data. Results Among the inpatient study participants, 74.3% reacted with a single antibody, 5.7% reacted with two kinds of antibodies, and 20.0% reacted with no antibodies.There was no remarkable difference in laboratory data for these groups.However, ALT decreased in a logarithmic-linear manner in conjunction with the development of illness.In HEV-infected patients, the ALT levels decreased more rapidly. Conclusion Immunological markers of viral infection and changes in ALT can facilitate etiological diagnosis of patients with hepatic injury that present with 15 × ULN of ALT.