Epidemiology and outcomes of marked elevations of alanine aminotransferase >1000 IU/L in an Australian cohort

Abstract

Background and Aim Marked elevations of alanine aminotransferase (ALT) are caused by a limited number of underlying pathologies, including hepatic ischemia, drugs/toxins, viral hepatitis, and—rarely—autoimmune hepatitis. The aim of this study was to determine the relative incidence of pathologies resulting in ALT greater than 1000 IU/L and factors predicting clinical outcomes in an Australian cohort. Methods A retrospective cohort study of all adult patients with ALT levels greater than 1000 IU/L between January 2013 and December 2015 was conducted at a large teaching hospital network in Australia. Multivariable logistic regression analysis was used to determine predictors of etiology and mortality. Results There were 287 patients identified with ALT levels greater than 1000 IU/L. The most common causes were ischemia (44%), drugs/toxins (19%), biliary obstruction (16%), and viral hepatitis (7%). Independent predictors of a diagnosis of ischemic hepatitis included (adjusted odds ratio; 95% confidence interval): hypotension (29.2; 8.2–104.7), chronic obstructive pulmonary disease (COPD) (20.2; 2.8–145.3), coronary artery disease (12.9; 1.7–98.9), congestive cardiac failure (7.8; 1.2–49.2), diabetes mellitus (7.4; 1.6–33.9), metabolic acidosis (6.2; 2.0–19.4), gamma‐glutamyltransferase < 135 IU/L (5.1; 1.5–17.6), and albumin <34 g/L (3.4; 1.1–11.0). Independent risk factors for all‐cause 28‐day mortality included: septic shock (14.7; 4.3–50.7), metabolic acidosis (7.3; 2.5–21.3), history of COPD (5.4; 1.6–17.8), cardiogenic shock (4.3; 1.6–11.7), prothrombin time ≥ 20 s (3.7; 1.5–9.2), and age ≥ 65 years (3.0; 1.3–7.2). Conclusions Ischemic hepatitis was the most common cause of ALT levels greater than 1000 IU/L and was associated with high mortality.

Keywords

• alanine aminotransferase
• alanine transaminase
• ischemic hepatitis