Lymphocyte-to-C-reactive protein ratio may serve as an effective biomarker to determine COVID-19 disease severity

Abstract

Objectives We aimed to evaluate the ability of lymphocyte-C-reactive protein ratio (LCR) to discriminate between different levels of severity of COVID-19 disease. Methods This retrospective observational single-center study was performed on 61 confirmed (PCR positive) COVID-19 patients between March and June 2020. The study population was separated into three groups: mild/moderate (n=24), severe (n=25) and critically ill (n=12). The optimal cut-off values of the LCR and neutrophil-to-lymphocyte ratio (NLR) in discriminating between patients with different severity levels were calculated by applying the receiver operating curve (ROC) analysis. Results At baseline, the LCR decreased significantly across the three severity groups (mild/moderate > severe > critically ill). ROC analysis showed that a mean LCR of 43.21 was the cut-off value which best discriminated patients with the critically ill disease from severe patients (sensitivity: 84% and specificity: 69%). The discriminative performance of LCR (ROC AUC 0.820) was better than that of NLR (0.751) in this regard. LCR, unlike NLR was able to distinguish severe patients from mild/moderate patients, with a cut off value of 458.19 (sensitivity: 80% and specificity: 45%). Conclusion LCR was observed to be able to distinguish COVID-19 infected patients of different severity (mild/moderate, severe and critically ill) and was superior to NLR in this regard.

Combination of cycle threshold time, absolute lymphocyte count and neutrophil:lymphocyte ratio is predictive of hypoxia in patients with SARS-CoV-2 infection

“…While a high lymphocyte:CRP ratio has also been proposed as an adverse prognostic factor in COVID-19, the non-specific nature of CRP may affect the routine applicability of this parameter. 45 …”

Diagnostic and prognostic significance of the lymphocyte/C-reactive protein ratio, neutrophil/lymphocyte ratio, and D-dimer values in patients with COVID-19

“…Elevated CRP level is also observed in patients having COVID-19 (Aktas, 2021). Studies have shown that the correlation of lymphocyte/CRP ratio with clinical severity is superior to NLR in COVID-19 patients (Bal et al, 2021;Lagunas-Rangel, 2020). Similar to CRP, elevated D-dimer value is a typical phenomenon in patients with COVID-19 (Wang et al, 2011).…”

“…The prognostic and diagnostic association of these parameters with COVID-19 remains unclear (Bal et al, 2021;ElshazliI et al, 2020). The present study compared the lymphocyte/CRP ratio (LCR), NLR, neutrophil count, MPV, PLT, neutrophil, CRP, and D-dimer values in patients with COVID-19 and a non-COVID-19 control group.…”

“…CRP is present in very low levels or even absent in healthy individuals. Significantly elevated CRP levels are observed in conditions such as infection and trauma (Bal et al, 2021).…”

Prognostic accuracy of inflammatory markers in predicting risk of ICU admission for COVID-19: application of time-dependent receiver operating characteristic curves

“…Although previous studies have shown that most patients with COVID-19 (nearly 80%) have initially mild or moderate disease and a favorable clinical outcome, others experience severe or critical illness. 2 Early diagnosis of these patients is crucial to decrease admissions to the intensive care unit (ICU) as well as the length of hospitalization, mortality rate, and hospital costs. 3 , 4 Cytotoxicity caused by the causative agent, SARS-CoV-2, in pulmonary endothelial cells and the consequences of severe inflammatory outcomes can cause serious and even life-threatening illness.…”