Diagnostic value of neutrophil to lymphocyte ratio to rule out chronic obstructive pulmonary disease exacerbation from acute heart failure in the emergency department

INTRODUCTION: This study was performed to determine whether neutrophil-lymphocyte ratio (NLR) optimizes the differential diagnosis of acute chronic obstructive pulmonary disease (COPD) exacerbation and acute heart failure (AHF) in patients admitting to the emergency department (ED) with dyspnoea. MATERIAL AND METHODS: The study group included 241 patients (135 males and 106 females) who were admitted to the ED with a complaint of dyspnoea between January 2016 November 2018 and were hospitalized with diagnosis of acute COPD exacerbation or AHF. RESULTS: White blood cell count, neutrophil, haemoglobin, haematocrit, NLR, and C-reactive protein values in patients with COPD exacerbation were significantly higher compared to those with AHF (p < 0.05). The largest areas under the ROC curve were obtained with NLR. The cut-off value for NLR was 9.39, with a sensitivity of 71% and a specificity of 61%. CONCLUSIONS: In conclusion, the NLR has diagnostic value to the conventional clinical assessment in patients with acute dyspnoea at ED, especially with acute COPD exacerbation requiring inpatient management. This may be an additional tool during the differential diagnosis of dyspnoea for emergency physicians in hospitals without advanced laboratory facilities.