Neutrophil volume distribution width: a new automated hematologic parameter for acute infection.

CONTEXT: The number of band forms and immature neutrophils increases during acute bacterial infection. However, the determination of band counts and other neutrophil morphologic changes, such as the presence of toxic granulation, toxic vacuolization, and Dohle bodies in the cytoplasm, is labor intensive and time consuming, as it requires manual examination by an experienced medical technologist.

OBJECTIVE: To investigate the value of the neutrophil volume distribution width (NDW), generated by VCS technology of the Coulter LH 750 hematology analyzer, as an additional predictor of acute infection.

DESIGN: Total white blood cell count, percentage of neutrophils, and NDW data from 70 patients with positive blood cultures for bacteria and from 35 age-matched control subjects were retrospectively analyzed.

RESULTS: A significant increase in the NDW was observed in the bacteremic patients compared with the controls (24.7 +/- 4.5 vs 19.0 +/- 1.5; P < .001). Such increase was observed even in patients with white blood cell counts less than 11,000/microL (23.0 +/- 5.6 vs 19.0 +/- 1.5; P < .001) or with percentages of neutrophils less than 85% (24.0 +/- 4.9 vs 19.0 +/- 1.5; P < .001). The more dramatic increases were seen in patients with leukocytosis (25.7 +/- 3.2, P < .001) or with neutrophilia (25.9 +/- 3.4, P < .001). Using an NDW cutoff of 23, a 100% specificity and a 69% sensitivity were achieved.

CONCLUSIONS: As a quantitative parameter, the NDW has potential for use as an additional indicator for diagnosing acute infection.