Mild AST elevation as an early sign of COVID-19 severity in a multicenter Madrid cohort

Introduction: liver enzyme elevation has been reported in SARS-CoV-2 disease (COVID-19) in heterogeneous cohorts, mainly from China. Comprehensive reports from other countries are needed. In this study, we dissect the pattern, evolution, and predictive value of such abnormalities in a cohort from Madrid, Spain. Methods: a retrospective study with a prospective 14-day follow-up of 373 patients with confirmed COVID-19 in five Madrid hospitals, including 50 outpatients. A COVID-19 severe course was defined as the need for mechanical ventilation. Results: a total of 33.1 % of hospitalized patients showed baseline AST elevation and 28.5 % showed ALT elevation, compared with 12 % and 8 % of outpatients (p <= 0.001). Baseline AST, ALT and GGT levels correlated with LDH and C-reactive protein (CRP) levels (r <= 0.598, p < 0.005). AST elevation was associated with other severity markers such as male sex, lymphopenia, and pneumonia on X-Ray (p < 0.05 for all). ALP and bilirubin levels were rarely increased. Patients with elevated baseline AST showed a progressive normalization of this enzyme and an increase in ALT and GGT levels. Patients with normal baseline AST showed a flattened evolution pattern with levels within the range. Patients with a severe course of COVID-19 more frequently showed elevated baseline AST than those with a milder evolution (54.2 % vs. 25.4 %, p < 0.001). Age, AST and CRP were independent risk factors for a severe course of COVID-19. Conclusion: mild liver enzyme elevation is associated with COVID-19 severity. Baseline AST is an independent predictor of severe COVID-19 course, and tends to normalize over time. ALT and GGT show a late elevation.