Neutrophil-to-lymphocyte ratio as an alternative to chest CT for assessing disease severity in COVID-19: evidence from a resource-limited setting

Abstract

Background: The COVID-19 pandemic created enormous challenges worldwide and also placed considerable burden on Bangladesh’s healthcare system, economy, and social structure. Chest CT scanswereidentified as a key diagnostic and prognostic tool, however, in resource-limited settings, cheaper and more accessible alternativesisrequired. Neutrophil-to-lymphocyte ratio (NLR), an inflammatory marker, may be a potential prognostic marker for morbidity and mortality of COVID-19 patients.This study aimed to evaluate the NLR as a cost-effective prognostic marker for COVID-19 severity and mortality by assessing its correlation with CT findings in a resource-limited setting.

Methods: This was an observational retrospective study carried out in Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh, between May 2020 and July 2021 among 237 patients with COVID-19 who fulfilled both inclusion and exclusion criteria. Hematological (neutrophil lymphocyte ratio and inflammatory indicators) and HRCTsererity was also evaluated. MannWhitney U test, Spearman correlation and ROC curve were used to analyse data using SPSS version 21.0 and p value < 0.05 was taken as significant.

Results: Among 237 patients, 165 (69.9%) were males and most patients (23.2%) were aged 51–60 years.Diabetes mellitus (20.6%)and hypertension (18.5%) were the most common comorbidities. Positive correlation of CT severity with inflammatory markers (CRP, ferritin, and D-dimer; rho = 0.434, 0.446, 0.425 respectively) was observed with p < 0.001 for each. An NLR cut-off of ³4.9 demonstrated 78% sensitivity and 75.3% specificity for predicting severe CT findings on ROC analysis.

Conclusion: An NLR³4.9, together with high ferritin, CRP, and D-dimer levels, may predict disease severity in COVID-19 patients and may offer a cost-effective prognostic alternative in resource-limited settings where CT imaging is unavailable or contraindicated.

BIRDEM Med J 2026; 16(2): 87-91