Immune-mediated liver injury following COVID-19 vaccination: A systematic review

Immune-mediated liver injury (ILI) following coronavirus disease 2019 (COVID-19) vaccination is not well-characterized. Therefore, we systematically reviewed the literature on ILI after COVID-19 vaccination. We searched PubMed, Cochrane, Ovid, Embase, and gray literature to include articles describing ILI following COVID-19 vaccination. Reports without confirmatory evidence from liver biopsy were excluded. Descriptive analysis, and study quality were reported as appropriate. Of the 1,048 articles found, 13 (good/fair quality; 23 patients) were included. Studies were primarily from Europe (n = 8), America (n = 2), Asia (n = 2), or Australia (n = 1). Patients were predominantly females (62.5%) of age 55.3 years (49.1-61.4), with an antecedent exposure to Moderna messenger RNA (mRNA)-1273 (47.8%), Pfizer-BioNTech BNT162b2 mRNA (39.2%), or ChAdOx1 nCoV-19 vaccine (13%). Pre-existing comorbidities (69.6%) were common, including liver disease in 26.1% and thyroid disorders in 13% of patients. About two-thirds of the patients were on concurrent medications (paracetamol, levothyroxine, statins, and non-steroidal anti-inflammatory drugs). Jaundice was the most common symptom (78.3%). Peak bilirubin, alanine aminotransferase, and alkaline phosphatase levels were 10.8 (6.8-14.8) mg/dl, 1,106.5 (757.0-1,702.5) U/L, and 229 (174.6-259.6) U/L, respectively. Histological findings were intense portal lymphoplasmacytic infiltrate with interface hepatitis. Steroids were used in 86.9% of patients, and complete response, recovering course, and death were reported in 56.5%, 39.1%, and 4.3% of patients, respectively. ILI following COVID-19 vaccination is rare. The diagnosis is established on temporal correlation, biochemical findings, and histopathology. Prognosis is excellent with corticosteroids. Causality establishment remains a challenge.