Significance of Hematological Parameters and Biochemical Markers in Severe Forms of Covid-19
Authors:   IOSUD University Ovidius Constanta, Doctoral School of Applied Sciences in Biology/ Biochemistry, VOICULESCU Anne–Lise Mihaela ,   Medical Center “Unirea”, ANGHEL Andreea ,   Faculty of Medicine, University Ovidius Constanta, GURGAS Leonard ,   Faculty of Medicine, University Ovidius Constanta, ROSOIU Natalia ,   IOSUD University Ovidius Constanta, Doctoral School of Applied Sciences in Biology/ Biochemistry; Faculty of Medicine, University Ovidius Constanta; Titular Member of the Academy of Romanian Scientists
Published: October 2022

SARS-CoV-2 is a new virus that affects the human population, about which not all the details are known, and for which the research is ongoing. Several common in vitro diagnostic tests have been implicated in the unfavorable progression of COVID-19, providing potentially important prognostic information. According to some synthesis studies, the progressively low values of the lymphocyte / leukocyte ratio, and progressively increased of the neutrophil / lymphocyte and neutrophil / platelets ratios, correlate with the more severe evolution of COVID-19. The existence of a number of lymphocytes <20% on day 10-12 indicates a pre-severe condition, and a number of <5% on days 17-19 indicates a critical one. D-dimers are the most important prognostic element in monitoring patients with severe forms of COVID-19. Elevated levels of D-dimers compared to the reference biological interval observed at hospitalization of patients with COVID-19 and their marked increase, up to 3-4 times the initial value, were associated with increased mortality, which probably reflects the activation of coagulation in infection / sepsis, cytokine storm and imminent organ failure. Increasing ALT values by more than 5 times the reference biological interval increased the risk of mortality of patients with COVID-19 by seven times. High levels of AST compared to the biological reference range were observed in both patients with non-severe COVID-19 disease as well as in a double the number of patients with severe disease. The value of serum creatinine at hospitalization is a predictor of the death of hospitalized patients for COVID-19. More frequent measurements of serum creatinine are recommended in the management of COVID-19 to improve the early detection of renal lesions in patients with COVID-19. At patients confirmed with COVID19, elevated levels of highly sensitive troponin I (hs-cTnI) were observed during hospitalization, and more than 50% of those who died had a significantly higher concentration of hs-cTnI compared to the biological interval of reference. Hyperferritinemia has been associated with an increased severity of COVID-19 disease, because of elevated ferritin levels compared to the reference biological range, the so-called "cytokine storm" is developed which can be fatal for half of COVID-19 patients, especially for the elderly. Lactate dehydrogenase (LDH) has been associated with altered outcomes in patients with viral infections. In an American study (n = 1532 COVID-19 patients), the association between elevated LDH levels (that were measured as soon as possible after hospitalization ) and the severity of the disease in patients with COVID-19 was assessed. Elevated LDH levels were associated with a 6 fold increase in the chance of developing severe symptoms and a 16 fold increase in mortality in patients with COVID-19. C-reactive protein (CRP) is part of the acute phase plasma proteins. COVID-19 increases CRP. This seems to correlate the severity and prognosis of the disease. Studies have found low levels of PCR in patients who do not require oxygen therapy (mean 11 mg / L,) compared to patients who have become hypoxemic (mean 66 mg / L).