Eosinophil count and neutrophil-lymphocyte count ratio as prognostic markers in patients with bacteremia: a retrospective cohort study.
BACKGROUND
There is scarce evidence on the use of eosinophil count as a marker of outcome in patients with infection. The aim of this study was to evaluate whether changes in eosinophil count, as well as the neutrophil-lymphocyte count ratio (NLCR), could be used as clinical markers of outcome in patients with bacteremia.


METHODS
We performed a retrospective study of patients with a first episode of community-acquired or healthcare-related bacteremia during hospital admission between 2004 and 2009. A total of 2,311 patients were included. Cox regression was used to analyze the behaviour of eosinophil count and the NLCR in survivors and non-survivors.


RESULTS
In the adjusted analysis, the main independent risk factor for mortality was persistence of an eosinophil count below 0.0454·10(3)/uL (HR = 4.20; 95% CI 2.66-6.62). An NLCR value >7 was also an independent risk factor but was of lesser importance. The mean eosinophil count in survivors showed a tendency to increase rapidly and to achieve normal values between the second and third day. In these patients, the NLCR was <7 between the second and third day.


CONCLUSIONS
Both sustained eosinopenia and persistence of an NLCR >7 were independent markers of mortality in patients with bacteremia.
Department of Epidemiology and Health Services Evaluation, Hospital del Mar, Barcelona, España. MTerradas@hospitaldelmar.cat
Roser
R
Terradas
Santiago
S
Grau
Jordi
J
Blanch
Marta
M
Riu
Pere
P
Saballs
Xavier
X
Castells
Juan Pablo
JP
Horcajada
Hernando
H
Knobel
D000368:Aged; D016470:Bacteremia / Q000097:blood* / Q000175:diagnosis* / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D001772:Blood Cell Count; D015331:Cohort Studies; D004804:Eosinophils / Q000166:cytology*; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000166:cytology*; D011379:Prognosis; D012189:Retrospective Studies
D015415:Biomarkers