Neutrophil-to-lymphocyte ratios as easy-to-use biomarkers for the diagnosis of active tuberculosis in children and adolescents

Background: The diagnosis of active tuberculosis (ATB) in children and adolescents is limited by non-specific symptoms, paucibacillary infection, and the low sensitivity of traditional tools. These limitations can lead to delayed treatment and increased complications. Methods: This retrospective study recruited 1,080 participants. We performed receiver operating characteristic (ROC) curves to evaluate the diagnostic performance of logarithmic neutrophil-to-lymphocyte ratio (logNLR) for ATB infection. We employed logistic regression, restricted cubic spline (RCS), stratified, and interaction analyses to evaluate the association between logNLR and ATB infection. Results: (MTB) exposure, and participants with CD4+ T cell counts>414 cells/μL or CD8+ T cell counts>238 cells/μL (all P