Lymphocytopenia and neutrophil-lymphocyte count ratio predict bacteremia better than conventional infection markers in an emergency care unit.
Crit Care. 2010 Oct 29;14(5):R192
Authors: de Jager CP, van Wijk PT, Mathoera RB, de Jongh-Leuvenink J, van der Poll T, Wever PC
ABSTRACT: INTRODUCTION: Absolute lymphocytopenia has been reported as a predictor of bacteremia in medical emergencies. Likewise, the neutrophil-lymphocyte count ratio (NLCR) has been shown a simple promising method to evaluate systemic inflammation in critically ill patients. METHODS: We retrospectively evaluated the ability of conventional infection markers, lymphocyte count and NLCR to predict bacteremia in adult patients admitted to the Emergency Department with suspected community-acquired bacteremia. C-reactive protein (CRP) level, white blood cell (WBC) count, neutrophil count, lymphocyte count and NLCR were compared between patients with positive blood cultures (n=92) and age and gender matched patients with negative blood cultures (n=92) obtained upon Emergency Department admission. RESULTS: Significant differences between patients with positive and negative blood cultures were detected with respect to CRP level (176 +/- 138 mg/l (mean +/- SD) versus 116 +/- 103 mg/l, respectively; p-value 0.042), lymphocyte count (0.8 +/- 0.5 x 10e9/l versus 1.2 +/- 0.7 x 10e9/l; p-value < 0,0001) and NLCR (20.9 +/- 13.3 versus 13.2 +/- 14.1; p-value < 0,0001) but not regarding WBC count and neutrophil count. Sensitivity, specificity, positive and negative predictive values were highest for the NLCR (77.2%, 63.0%, 67.6% and 73.4%, respectively). Area under the receiver operating characteristic curve was highest for the lymphocyte count (0.73; confidence interval: 0.66-0.80) and the NLCR (0.73; 0.66-0.81). CONCLUSIONS: In an emergency care setting, both lymphocytopenia and NLCR are better predictors of bacteremia than routine parameters like CRP level, WBC count and neutrophil count. Attention to these markers is easy to integrate in daily practice and without extra costs.
PMID: 21034463 [PubMed - as supplied by publisher]