P-7 LIVER INJURY AFTER COVID-19 VACCINATION COMPARED TO POST-INFLUENZA VACCINES: RETROSPECTIVE COHORT STUDY

INTRODUCTION AND OBJECTIVES: Cases suggestive of immune-mediated acute hepatitis following SARS-CoV-2 vaccination have been reported. The risk of liver injury after Covid-19 vaccination is unknown. This study aimed to estimate the cumulative incidence of liver injury within 90 days after the Covid-19 vaccine, defined as the occurrence of AST and/or ALT increases at least two times the limit of normal or ALP increases at least x 2. To compare with an active comparator group (influenza vaccine). MATERIALS AND METHODS: Retrospective cohort study. We analyze a consecutive sample of adult patients vaccinated with Covid-19 vaccines (Sputnik, AstraZeneca/Oxford, Covishield, or Sinopharm) between January 1 and May 30, 2021, and a historical control group vaccinated with influenza between March 1 and July 30, 2019. Qualifying labs were collected as part of routine clinical care or the development of symptoms. RESULTS: From a total of 29,918 subjects who received the Covid-19 vaccine in 2021 and 24,753 who received the Influenza vaccine in 2019, 130 and 148 patients, respectively, were excluded because of previously altered liver function tests or known hepatic disease. Both groups were comparable in age (73 years old (IQR 65-80), p=0.125) and gender (67% were females). In the Influenza group were more dysmetabolic and immunosuppressed patients. A total of 269 and 273 patients, respectively, presented altered liver function tests within 90 days post-vaccination. The cumulative incidence of liver injury was 4.6 per 1,000 (95% CI 3.9-5.5) for Covid-19 and 5.1 per 1,000 (95%CI 4.3-6.1) for Influenza (p=0.453). Although, two patients from the COVID group had a more severe injury, with hyperbilirubinemia, development of autoantibodies and requirement of steroids for disease control. CONCLUSIONS: The occurrence of events was similar in subjects vaccinated with Covid-19 compared to the control group. Acute hepatitis characteristics arising after the COVID-19 vaccine needs to be further clarified.