VALUE of LABORATORY PARAMETERS in the CLINICAL MONITORING of PATIENTS with SARS-COV-2 INFECTION (COVID-19)

Background: Association between some analytical parameters and clinical evolution of patients infected by SARS-COV-2 is a controversial issue. Aims: Review the relationship between laboratory parameters and severity and/or lethality of the COVID-19. Methods: Observational, cross-sectional and retrospective study. Data obtained from electronic health record of patients over18 years of age admitted in our hospital, between March and May 2020 with suspected SARS-COV-2 infection. After descriptive statistical study, we did an inferential analysis using Mann-Whitney U test for independent samples, in order to verify association between the results of analytical parameters and the clinical severity (defined by hospitalization in conventional ward vs. intensive care units (ICU)) and/or lethality (alive vs. death at the end of the study). Results: 668 patients were included, 345 men (52%) and 323 women (48%), with a median age of 70 years. 80% of patients had previous comorbidities,10% were admitted to the ICU, and17% died. Differences were found in hematimetric parameter between the different groups: leukocytes (103/μl): 8.3 in ICU patients vs. 6.5 in those admitted to the ward;platelet count (103/μl) of182l in death patients vs. 223 in survivors;hemostasis parameters: D-dimer (DD) (μg/L) of1379 and1236 in deceased and admitted to the ICU respectively, compared to 734 and 786 in survivors and not admitted to ICU;and biochemical figures (increase in C-reactive protein (CRP), lactate dehydrogenase (LDH) or cardiac enzymes, the latter, especially, in patients who were deceased, with a median ultrasensitive troponin I (ng/L) of 34.75 vs. 7.1 in survivors. The differences were statistically significant (p value <0.01). Summary/Conclusion: Correlation exist between severity of infection and the increase in leukocytes, neutrophils, DD, CRP and LDH, and lymphopenia, in our sample. Decrease in the platelet count and the increase in cardiac enzymes were associated with an increased risk of mortality.