Clinical features and mechanism of liver injury in patients with mild or moderate coronavirus disease 2019.

Background And Aim: We aimed to identify clinical features that suggest that coronavirus disease 2019 (COVID-19) should be a differential diagnosis in patients presenting with a chief complaint of fever and abnormal liver function.

Methods: We retrospectively studied the presence or absence of abnormal liver function in 216 patients diagnosed with mild-moderate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between February and September 2020.

Results: Abnormal liver function was observed in 51 patients with mild-moderate COVID-19. The median peak aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were 57.5, 75.5, and 332.5 U/L, respectively. The median number of days from symptom onset to peak AST, ALT, and LDH were 8.5, 9, and 8.5, respectively. The median peak LDH/AST ratio was 9.0. Low lymphocyte-to-white blood cell ratio and elevated LDH were found to be independent contributing factors for intensive care unit (ICU) admission on a multivariate analysis.

Conclusions: AST-predominant AST/ALT/LDH elevation peaking 8-9 days after symptom onset and not accompanied by elevated alkaline phosphatase or gamma-glutamyl transferase may be a useful clinical feature for differentiating COVID-19 from other diseases. Since the median LDH/AST ratio was 9.0, it seems that the abnormal liver function caused by SARS-CoV-2 is an indirect damage to liver cells due to elevated cytokine levels caused by liver-infiltrating lymphocytes. SARS-CoV-2 infection should be considered in patients presenting with a chief complaint of fever and liver injury; those with a high lymphocyte-to-white blood cell ratio or and a high LDH/AST ratio may be admitted to the ICU.