Hypertransaminasemia in non-cirrhotic critically-ill patients

Hypertransaminasemia - acute elevation of alanine aminotransferase and aspartate aminotransferase - is prevalent in non-cirrhotic adults admitted to the intensive care unit (ICU) and often signals extra-hepatic pathophysiology rather than intrinsic liver disease. To synthesise contemporary evidence on aetiology-driven diagnosis, management and emerging biomarkers of hypertransaminasemia in critically ill patients. We performed a structured search of PubMed, EMBASE and CENTRAL (January 2010-June 2025). The search was restricted to full-text articles that were published in English in peer-reviewed journals. Hypoxic liver injury is the leading cause of hypertransaminasemia in non-cirrhotic ICU patients and is characterized by a ≥ 50% alanine aminotransferase/aspartate aminotransferase fall within 72 hours after haemodynamic stabilisation. Idiosyncratic drug-induced liver injury remains uncommon yet explains about 13% of acute liver-failure cases in Western registries. Sepsis-associated liver injury presents mainly as conjugated hyperbilirubinaemia with modest transaminase rise, whereas parenteral-nutrition-associated liver disease is dominated by cholestasis after > 2 weeks of parenteral feeding. Early optimisation of macro-/micro-circulation, rational deprescribing of hepatotoxins, rapid source control of infection and prompt transition to enteral nutrition are outcome-modifying interventions across all phenotypes. In the ICU, aminotransferase elevation should be interpreted as a dynamic biomarker of systemic distress. A pattern-recognition algorithm integrating clinical context, enzyme kinetics and novel biomarkers (glutamate dehydrogenase, microRNA-122, high-mobility group box-1) can expedite aetiology-specific therapy and deserves prospective validation.