Sedimentation characteristics of leucocytes can predict bacteraemia in critical care patients.
BACKGROUND
Early detection of blood stream infection can be lifesaving, but the results of blood cultures are not usually available before 24 hours after blood sampling. An earlier indication would lead to the initiation of immediate and adequate antibiotic treatment with obvious advantages for the patient.


OBJECTIVE
To evaluate the ability of leucocyte count, serum procalcitonin (PCT) concentration, erythrocyte sedimentation rate (ESR), and leucocyte antisedimentation rate (LAR) in predicting the blood culture results in critical care patients.


METHODS
39 consecutive patients with their first febrile episode were investigated prospectively. LAR was determined as the percentage of leucocytes crossing the midline of a blood column upward during one hour of gravity sedimentation. The relevance of the different variables was estimated by likelihood ratio tests and area under receiver operating characteristic curves (AUC).


RESULTS
23 patients had positive blood culture results and 16 negative. LAR was significantly higher in bacteraemic patients than in non-bacteraemic patients (p = 0.001), but leucocyte count, ESR and PCT level failed to show significant differences. Leucocyte count, PCT, and ESR yielded low discriminative values with the AUCs of 0.66, 0.64, and 0.52, respectively. LAR provided a likelihood ratio of 3.6 and an AUC of 0.80 (95% confidence interval, 0.64 to 0.95) (p = 0.002).


CONCLUSIONS
The simple LAR test can predict blood culture results and support urgent treatment decisions in critical care patients in their first febrile episode.
Bogar
L
L
Department of Anaesthesiology and Critical Care, University of Pecs, Hungary. bogar@clinics.pote.hu
Molnar
Z
Z
Kenyeres
P
P
Tarsoly
P
P
D000328:Adult; D000368:Aged; D019540:Area Under Curve; D016470:Bacteremia / Q000097:blood / Q000175:diagnosis*; D001799:Blood Sedimentation; D002116:Calcitonin / Q000097:blood; D015740:Calcitonin Gene-Related Peptide; D002465:Cell Movement; D003422:Critical Care; D005260:Female; D005334:Fever / Q000097:blood / Q000382:microbiology*; D006801:Humans; D007958:Leukocyte Count; D007962:Leukocytes / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood; D012680:Sensitivity and Specificity
C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide