Background and study aims: COVID-19 has spread around the globe in short span of time. We have been working as team to observe the pandemic since it hits our country and have been observing the different demographic, hematologic and inflammatory mediators that affect the outcome of the disease. To facilitate the clinicians working in isolation units and COVID-ICU, we tried to determine the clinical sensitivity of different hematological indices to predict the severity and mortality in COVID-19.
Patients and Method: We did a cross sectional study covering 182 patients, 112(61.53%) males and 70(38.46%) females, who were tested COVID-19 positive in two tertiary care hospitals of Khyber Pukhtunkhwa (Qazi Hussain Ahmed Medical Complex Nowshera & Hayatabad Medical Complex Peshawar). Hematological markers were assessed for their diagnostic and prognostic values. Independent t-test was used in groups with different outcome (discharged satisfactorily vs expired) regarding hemoglobin concentration, neutrophil to lymphocyte ratio (NLR), absolute neutrophilic count (ANC) and platelet count.
Receiver operating characteristics (ROC) curve was used as statistical tool to determine the relationship of clinical sensitivity and specificity of different hematological indicators to predict the worst outcome in COVID-19.
Results: A statistically significant difference (p < 0.05) exists between the groups (discharged satisfactorily vs Expired) regarding NLR, ANC and platelet count. NLR is most reliable hematological prognostic indicator in COVID-19 to predict mortality/worst outcome with an area under curve (AUC) of 0.68 on ROC. The clinical sensitivity of hematological markers on ROC curve was: Hb%<11g/dl (59.1%), TLC>7.2k (75.9%), ANC >3.9% (86.2%), ALC1.8 (93.1%) and PLT Conclusion: The clinical sensitivity as measured by AUC for hematological markers i.e. NLR, ANC and platelet count is statistically significant and an abnormally elevated levels of hematological markers indicate the severity of the disease. Likewise leukocytosis, neutrophilia and lymphopenia, with high NLR and low platelet count are worst prognostic markers in COVID-19.