ABSTRACT
Introduction Cytokine storm is central in the pathobiology of Coronavirus disease 2019 (COVID-19). The pro-inflammatory state and hypoxia disrupt erythropoiesis leading to alterations in red cell distribution width (RDW) and hematocrit. Platelet production increases alongside its destruction, inviting newly formed immature platelets into the circulation. Thus, the platelet distribution width (PDW) and mean platelet volume (MPV) are also affected. The study's objective is to analyze these indices and C-reactive protein (CRP) to elucidate prognostic insights in COVID-19 patients at the time of admission. Methodology This study was a retrospective cross-sectional study conducted at Chigateri General Hospital, attached to JJM Medical College, Davangere, over two months, July and August of 2020. Patients falling under categories B and C according to the interim guidelines issued by the Ministry of Health and Family Welfare, Government of India were enrolled in this study. Patients requiring mechanical ventilation and those with a prior diagnosis of malignancy were excepted from the study. Results The study population comprised a total of hundred patients. Seventy-five patients survived the disease and were discharged; twenty-five patients succumbed to the viral illness. The mean age of survivors (43.0 +/- 13.6 years) was significantly lesser than that of non-survivors (59.1 +/- 11.5 years) (p <0.001). RDW was significantly different among survivors (p=0.002); PDW and CRP were lower among the deceased (p=0.05 and p=0.10, respectively). Cut off values for RDW as 15%, CRP as 67 mg/l, and PDW as 17% were significantly associated with mortality. Hematocrit and MPV were not significantly associated with mortality. RDW has a sensitivity of 92% and a negative predictive value of 95% in predicting mortality. Discussion RDW showed a significant association with increased mortality. Impaired cell-mediated immunity at the onset of infection is responsible for rapid progression to moderate or even severe COVID disease. Since the investigations in our study were ordered at the time of admission, it may lead us to believe that higher RDW is associated with a better patient outcome. Lower C-reactive protein levels are associated with higher mortality. CRP is a non-specific marker for inflammation. Raised CRP is customarily an indicator of acute inflammation. Notwithstanding, the raised CRP may be an indicator of baseline immune response in early COVID infection. High PDW shows a significant association with increased mortality. The pathobiology of change in platelet indices in COVID-19 patients is presumably multifactorial: infection of the bone marrow; autoimmune platelet destruction; platelet sequestration. Conclusion Red cell distribution width, platelet distribution width, and C-reactive protein are useful early predictive markers of mortality in COVID-19. Although serial investigations would provide a better picture, these indices at admission can gauge the clinical outcome early in the disease. As there is still a lot to be understood about the natural history of COVID-19, our study aims to propose relatively inexpensive indices of mortality that can aid efficient management.
ABSTRACT
Background and objective Neutrophils are primarily responsible for activating the immune system, and systemic inflammation destroys CD4+ T lymphocytes and increases suppressor CD8+ T lymphocytes, thereby leading to an increased neutrophil-to-lymphocyte ratio (NLR). An increase in the apoptosis of lymphocytes leads to lymphopenia and elevated thrombopoietin (THPO) promotes megakaryocyte production. The reflections of these inflammatory changes can be vital in gauging the progression of the disease. This study aimed at examining the prognostic value of normal and derived neutrophil-to-lymphocyte, lymphocyte-to-monocyte, platelet-to-lymphocyte, and mean platelet volume (MPV)-to-platelet count ratios in patients with coronavirus disease 2019 (COVID-19). Methodology This was a retrospective cross-sectional study conducted in the wards of Chigateri General Hospital, Davangere for a period of two months. Complete blood count was ordered for all patients at the time of admission along with confirmation of the disease by reverse transcription-polymerase chain reaction (RT-PCR). Results The final study population consisted of 100 patients. The mean age of patients who survived (43 years) was significantly lower than the mean age of non-survivors (59.1 years), with a p-value of <0.001. NLR was raised in 60% of the population and was significantly higher in patients who survived the disease, with a p-value of 0.004. The platelet-to-lymphocyte ratio (PLR) also followed a similar trend with a p-value of 0.017. Even though the lymphocyte-to-monocyte ratio (LMR) also mimicked the trend, the statistical association was not significant (p-value: 0.09). The derived NLR and MPV-to-platelets ratios were not found to be significantly associated with mortality in this study. Discussion Younger patients had better clinical outcomes in our study population compared to the geriatric age group. A significant correlation between LMR and mortality was observed when a cut-off of 2.5 was considered as a differentiating benchmark. Conflicting trends were observed in NLR and PLR in our study; however, LMR was in accordance with most other studies. The phase that a patient is in with regard to the natural history of the disease also influences the blood cell ratios. Nonetheless, all three ratios can be used as crucial screening and prognostic tools as they are readily available with the help of a complete hemogram. This is an investigation modality that is widely accessible even in remote areas and resource-limited settings. Conclusion These hematological ratios can facilitate in categorizing the disease severity and progression in patients, thereby enabling us to make appropriate and informed clinical decisions. Since the second wave of the novel coronavirus is on the verge of arrival, it is imperative to channel resources for the patients early in their disease course to ultimately prevent complications and reduce mortality.