Is Neutrophil-lymphocyte ratio useful for differential diagnosis between pulmonary tuberculosis and bacterial community-acquired pneumonia.

Abstract

Differential diagnosis between pulmonary tuberculosis (PTB) and bacterial community-acquired pneumonia (CAP) is often challenging. The neutrophil-lymphocyte count ratio (NLR) has been demonstrated to be a useful biomarker for predicting bacteremia. We investigated the usefulness of the NLR for discriminating PTB from CAP in an intermediate tuberculosis burden country. Methods: Consecutive adult patients hospitalized for PTB (G1: n=105) and bacterial CAP (G2: n=80) from January 2014 to december 2016 were included. White blood cells (WBC) differential count, CRP and NLR were determined before treatment and were compared in G1 and G2. Exclusion criteria were conditions affecting WBC counts, absence of WBC differential count or CRP data, or change to other diagnosis during follow-up. Results: There was no differences between G1 and G2 according to gender, smoking and medical history. However, patients of G1 were younger (40.5±17 vs. 51±17; p Conclusion: NLR seems to be supportive in differentiation of PTB and BCAP. More studies on this issue are needed to determine optimal cut-off value for discriminating patients with pulmonary TB from patients with bacterial CAP.