Hematological and biochemical parameters as diagnostic and prognostic markers in SARS-COV-2 infected patients of Pakistan: a retrospective comparative analysis

Objectives: This study was conducted to investigate alteration in blood parameters and their association with the presence, severity, and mortality of COVID-19 patients as the data on hematological abnormalities associated with the Pakistani COVID-19 patients is limited.

Methodology: A double-centered, hospital-based comparative retrospective case study was conducted, to include all the admitted patients (n = 317) having COVID-19 Polymerase chain reaction (PCR) positive. The control group (n = 157) tested negative for COVID-19.

Results: Of 317 admitted cases, the majority were males n = 198 (62.5%). Associated comorbidities, lower lymphocytes, platelets, and higher White blood cells, neutrophil, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were found in COVID-19 cases as compared to healthy controls (p < 0.001 for all). The biochemical parameters of cases including Ferritin, D-Dimer, CRP, IL-6, LDH, ALT, AST, and APTT also showed a statistically significant difference compared with standard values (p < 0.001 for all). However, their comparison with a severity level of the severe and non-severe groups showed significance for WBCs, neutrophils, NLR (p < 0.001 for all), and PLR (p = 0.06) only. Receiver operating characteristic curve analysis showed that NLR had the highest area under curve (0.84) followed by 1/lymphocyte (0.82), neutrophils (0.74), PLR (0.67),1/platelets (0.68) and WBC's (0.65). Comparison of cases and controls with recommended cut-off values derived from sensitivity and 1-specificity was also done (p < 0.001).

Conclusion: Monitoring all the hematological and biochemical parameters including novel hemograms NLR, PLR can aid clinicians to identify potentially severe cases at early stages and initiate effective management in time which may reduce the overall mortality of COVID-19 patients.