The neutrophil-lymphocyte count ratio in patients with community-acquired pneumonia.
OBJECTIVE
The neutrophil-lymphocyte count ratio (NLCR) has been identified as a predictor of bacteremia in medical emergencies. The aim of this study was to investigate the value of the NLCR in patients with community-acquired pneumonia (CAP).


RESULTS
Consecutive adult patients were prospectively studied. Pneumonia severity (CURB-65 score), clinical characteristics, complications and outcomes were related to the NLCR and compared with C-reactive protein (CRP), neutrophil count, white blood cell (WBC) count. The study cohort consisted of 395 patients diagnosed with CAP. The mean age of the patients was 63.4 ± 16.0 years. 87.6% (346/395) of the patients required hospital admission, 7.8% (31/395) patients were admitted to the Intensive Care Unit (ICU) and 5.8% (23/395) patients of the study cohort died. The NLCR was increased in all patients, predicted adverse medical outcome and consistently increased as the CURB-65 score advanced. NLCR levels (mean ± SD) were significantly higher in non-survivors (23.3 ± 16.8) than in survivors (13.0 ± 11.4). The receiver-operating characteristic (ROC) curve for NLCR predicting mortality showed an area under the curve (AUC) of 0.701. This was better than the AUC for the neutrophil count, WBC count, lymphocyte count and CRP level (0.681, 0.672, 0.630 and 0.565, respectively).


CONCLUSIONS
Admission NLCR at the emergency department predicts severity and outcome of CAP with a higher prognostic accuracy as compared with traditional infection markers.
Department of Emergency Medicine and Intensive Care, Jeroen Bosch Ziekenhuis, 's-Hertogenbosch, The Netherlands. p.de.jager@jbz.nl
Cornelis P C
CP
de Jager
Peter C
PC
Wever
Eugenie F A
EF
Gemen
Ron
R
Kusters
Arianne B
AB
van Gageldonk-Lafeber
Tom
T
van der Poll
Robert J F
RJ
Laheij
D000368:Aged; D019540:Area Under Curve; D002097:C-Reactive Protein / Q000032:analysis; D017714:Community-Acquired Infections / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007958:Leukocyte Count / Q000379:methods*; D018655:Lymphocyte Count / Q000379:methods*; D008875:Middle Aged; D009426:Netherlands; D009504:Neutrophils / Q000166:cytology*; D011014:Pneumonia / Q000097:blood*; D011446:Prospective Studies; D012372:ROC Curve
D002097:C-Reactive Protein