A Retrospective Study into Etiology, Clinical Outcomes and Prognostic Factors of Severe Acute Liver Injury in Hong Kong

Chan Ka Yan Gloria*, Tsang Woon Choy Steven

Background: Severe Acute Liver Injury (ALI) contributes to significant morbidity and mortality in hospitalized patients. Early recognition, identification and treatment of the underlying cause are necessary for better outcome. This study aimed to investigate the common causes of severe elevation of Alanine Aminotransferase (ALT) in Chinese patients admitted to hospital in Hong Kong, and also to determine the clinical outcomes and prognostic factors associated with the ALI.

Methods: This was a retrospective, single center cohort study conducted in a regional hospital between January 2017 and December 2019. Patients’ data admitted with ALT ≥ 1000 U/L were retrieved from the Department of Pathology data base. Their baseline clinical demographics, laboratory profiles and the etiology of ALI were analyzed. The primary outcome was all cause 30-day mortality. Independent predictors for mortality were also assessed.

Results: A total of 313 patients were analyzed. The most common causes of severe ALI in our study were ischemic hepatitis (52.1%), biliary pathology (19.2%), viral hepatitis (14.1%) and drug induced liver injury (6.4%). The overall 30-day mortality rate was 43.1%. Ischemic hepatitis (OR 40, 95% CL 5.1-315.2, p<0.001) and hepatitis due to infiltrative liver disease (OR 26, 95% CI 1.8 – 367.7, p=0.002) were associated with higher mortality. Each etiology shows a distinct clinical and biochemical profile.

Conclusion: Ischemic hepatitis was the leading cause of severe ALI and was associated with high mortality. Early diagnosis and prompt treatment would be essential. Biliary pathology was not an uncommon cause of marked ALT elevation in Hong Kong and should gain its recognition in the differential diagnosis.