Pretreatment neutrophil-to-lymphocyte ratio in peripheral blood was associated with pulmonary tuberculosis retreatment

The neutrophil-to-lymphocyte ratio (NLR) is a readily available biomarker associated with recurrence and survival in various diseases. The objective of this study was to investigate the relationship between NLR and pulmonary tuberculosis (PTB) retreatment. This was a case-control study that included 306 newly diagnosed cases of PTB in the clinical database of the Infectious Hospital of Wuxi from December 2009 to December 2011. Of the 306 patients, a total of 68 cases were followed up with TB retreatment. The remaining 238 PTB patients who completed anti-TB treatment and were cured without retreatment were selected as controls. According to the ROC curve, the best cut-off value of NLR was 2.53, with a sensitivity of 70.6% and a specificity of 45.4%. The NLR ≥ 2.53 before anti-TB treatment was associated with PTB retreatment (OR = 1.994, 95% CI: 1.116-3.564; adjusted OR (AOR) = 2.409, 95% CI: 1.212-4.788). The retreatment rates with NLR ≥ 2.53 and NLR < 2.53 were 27.1% and 15.5%, respectively, with a significant difference (log-rank test; = 0.010). Additionally, cavitation on chest X-ray (OR = 2.922, 95% CI: 1.654-5.411; AOR = 2.482, 95% CI: 1.230-5.007), history of smoking (OR = 2.202, 95% CI: 1.158-3.493; AOR = 2.321, 95% CI: 1.135-4.745) and age ≥ 60 (OR = 3.828, 95% CI: 1.626-9.015; AOR = 2.931, 95% CI: 1.122-7.653) were also associated with PTB retreatment. NLR ≥ 2.53 is predictive of PTB retreatment. Otherwise, initial cavitation on chest X-ray, history of smoking, and age of ≥ 60 are also risk factors for PTB retreatment.