Leukocyte Cpd by in the Detection of Sarscov- 2 Pneumonia

ABSTRACT

Introduction: Leukocyte differential, present certain features in SARS-CoV2 infected patients neutrophilia, lymphopenia and morphology alterations, which could be useful for screening. Cell population data (CPD) are reported as part of leukocyte differentials by Sysmex XN analyze;they are morphometric parameters that characterize neutrophils, lymphocytes and monocytes and classify them according to their volume, granularity and their content in nucleic acids. CPD reflects in numbers the changes in morphology and activation status triggered by infections. We aimed to evaluate the predictive power of CPDs for the differential diagnosis of COVID19 versus non-COVID19 pneumonia. Method(s) The prospective, observational, multicenter study was conducted in 3 hospitals, including patients > 18 years admitted with the diagnosis community-acquired pneumonia in the period November 2019 - October 2020. Complete blood count were analyzed using Sysmex XN counters. Diagnosis of SARS-CoV-2 infection was done using real-time reverse transcriptionpolymerase chain reaction. Patients were divided into two groups (1) referral cohort in a hospital for the development of the model (2) the sample of two other hospitals for its validation. Multivariate logistic regression model has been developed for the detection of COVID patients. Robustness of the model has been evaluated by means of the area under the ROC curve and the calibration of the model. Statisticalsignificance p < 0.05. Result(s) 598 patients were recruited, 322 in the referral cohort and 276 in the validation group. The average age was 67.0 years (Standard Deviation 14.59 years ) and 61.49 % male. Neutrophil lymphocyte ratio, NE-WZ, LYY, LY-Z, LY-WX, LY- WY, MO- WY, MO-Z were included in the multivariate analysis, and presented a significant association for the differential diagnosis of SARS-CoV-2 infection with AUC of 0.84 (95% CI 0.82-0.92) in the referral cohort and 0.77 (0.69-0.85) in the validation cohort Conclusion(s) Leukocyte differential and CPDs could be very useful in the differential diagnosis of SARS-CoV-2 pneumonia and lead to a cheap and early diagnosis of the disease.