Correlation of platelet counts with Coronavirus Disease 2019 outcome in the second wave at a tertiary care center

Abstract

Background: A novel coronavirus, severe acute respiratory syndrome coronavirus 2, was first identified in December 2019 as the cause of a respiratory illness designated coronavirus disease 2019 (COVID-19). Laboratory parameters particularly the inflammatory markers such as D-dimer, C-reactive protein, ferritin, and others have been studied extensively and have been applied in categorizing the disease severity as well. However, studies regarding the role of platelet counts in the disease pathophysiology are limited. Aims: (1) To assess platelet counts in COVID-19 patients, (2) To correlate platelet counts with clinical outcome of COVID-19 patients. Materials and Methods: The present study was conducted on 200 patients admitted to ESIC MC and PGIMSR MODEL HOSPITAL, Bengaluru, during the study period from August 2020 to July 2021. Data were collected from case files of patients presenting to the Department of General Medicine Triage and COVID Ward/intensive care unit at ESIC Bangalore, fulfilling the inclusion criteria. Results: The mean platelet counts of the patients admitted with COVID-19 are 2.18 ± 1.32 × 105/mm3. Platelets among those who were discharged were 2.16 ± 1.09 × 105/mm3 and those among those who died was 1.71 ± 0.56 × 105/mm3. This difference was statistically significant with a P = 0.03. We also see that the lymphocyte counts are 14.03 ± 10.75% among those who were discharged and 10.13 ± 5.89% among those who succumbed to death. Conclusion: The present study concludes that COVID-19 patients with thrombocytopenia and lymphopenia are at increased risk of mortality. Hence, platelet count and lymphocyte count can be taken as prognostic indicators of COVID-19.