The lactate dehydrogenase to lymphocyte ratio in evaluating the prognosis of patients with severe COVID-19

Abstract

Inflammatory biological parameters are altered in patients with COVID-19 depending on its severity. The objective of our study is to find a score to assess the prognosis of patients with severe COVID-19. This is a retrospective study of patients with severe COVID-19 hospitalized in the intensive care units of Ibn Sina Hospital in Rabat. The study involves a total of 197 patients. The biological parameters were collected and evaluated in order to recognize the factors of poor prognosis of severe COVID-19. In our cohort, 133 patients died (67.51%) and had a higher average age (p <0.001). A statistically significant correlation was found in this group of patients for procalcitonin (p =0.005), lactate dehydrogenase (p =0.02) and ferritin (p=0.017). The lactate dehydrogenase/lymphocyte ratio (LLR) had the highest accuracy among the calculated combined scores. The LLR AUC was 0.628 (95% CI: 0.549-0.708) and the optimal cut-off value was 341, which gave a sensitivity of 91% and a specificity of 84%. The LLR is a good predictor of the poor prognosis of patients with severe COVID-19.