Haematology audit of 801 COVID-19 patients' basics and beyond- Prospective observational study.

Background and Objective: COVID-19 has become a major health concern since 2020. Its clinical presentation varies from asymptomatic cases to cases with respiratory failure needing ICU management. It has created a huge burden on limited health care resources. We need better understanding of the pathogenesis and interplay between virus and other factors which decide outcome. We seek biomarkers to predict severe illness to offer better triaging of patients to provide hospital-based care to the patients at risk of severe illness. Material and Methods: We took 801 consecutive RT-PCR-positive COVID cases coming to our center. Their hematological work-up, such as complete blood count, peripheral smear, reticulocyte count, and G6PD activity, was tested. The pattern of hematological abnormalities was assessed across disease severity groups to identify predictors of severe illness from basic investigation. Also, the interplay between iron deficiency and possible hemoglobinopathy trait and COVID was explored. Results Discussion and Conclusion: We found old age, male gender, diabetes, neutrophilia, lymphopenia, monocytopenia, and eosinopenia at presentation to be associated with moderate to severe illness and may help in triaging with other inflammatory and radiological parameters. We found thrombocytosis rather than thrombocytopenia as a predictor of severe illness. Our preliminary findings suggest the need to explore the protective role of hemoglobinopathy traits and iron deficiency against severe COVID illness.