SARS-CoV-2 viral persistence based on cycle threshold value and liver injury in patients with COVID-19

Wong, Grace Lai-Hung; Yip, Terry Cheuk-Fung; Wong, Vincent Wai-Sun; Tse, Yee-Kit; Hui, David Shu-Cheong; Lee, Shui-Shan; Yeoh, Eng-Kiong; Chan, Henry Lik-Yuen; Lui, Grace Chung-Yan

BACKGROUND: Liver injury in patients with COVID-19 is common and prognostic. Direct viral tropism of SARS-CoV-2 for angiotensin-converting enzyme 2 receptors in hepatocytes may be one of the mechanisms of liver injury. We aimed to determine the role of viral persistence of SARS-CoV-2, based on cycle threshold (Ct) value, in liver injury in COVID-19. METHODS: This was a territory-wide retrospective cohort study of all public hospitals in Hong Kong. Laboratory-confirmed COVID-19 were identified. Serial liver biochemistries and Ct value of SARS-CoV-2 RNA were analyzed. RESULTS: We identified 7,622 COVID-19 patients (mean age 47 years, 48.2% male) diagnosed from 24 March to 1 January 2021 who had serial liver biochemistries and Ct values. 1,363 (17.9%) COVID-19 patients had ALT/AST elevations with two temporal patterns – early (within first 14 days from symptom onset) and late (after 14 days from symptom onset). COVID-19 patients with ALT/AST elevations had a lower Ct value at admission (23 vs. 25; P<0.001), day 5 (24 vs. 26; P<0.001) and day 20 (31 vs. 32; P<0.001) after admission, compared to those without ALT/AST elevations. COVID-19 patients with ALT/AST elevations had a longer duration from first positive to first negative RT-PCR of SARS-CoV-2 (13 vs. 9 days; P<0.001). ALT/AST elevation and presence of diabetes were the independent risk factors of viral persistence. CONCLUSIONS: Liver injury in COVID-19 is linked to a higher SARS-CoV-2 viral load during the early phase of infection, signifying a possible direct viral injury to liver. Prolonged viral persistence of SARS-CoV-2 is associated with liver injury.