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Abstract & Commentary
And the Bands Played On
By Stan Deresinski, MD, FACP , Clinical Professor of Medicine, Stanford, Associate Chief of Infectious Diseases, Santa Clara Valley Medical Center, is Editor for Infectious Disease Alert .
Synopsis: Physicians may not be able to rely upon their clinical laboratory to accurately report the neutrophil "band count."
Source: Geissal ED, Coffey T, Gilbert DN. Clinical importance of the failure to detect immature neutrophils by an automated hematology analyzer. Infect Dis Clin Pract. 2010; 18:374-378.
Knowledge of the presence of an increased proportion of band neutrophils (neutrophils with non-segmented nuclei) is believed by many clinicians to assist them in the diagnosis and management of some patients with suspected or known infection. Automated hematology analyzers, however, are not capable of providing a "band count." The identification of band neutrophils instead depends upon manual review of a blood smear. The need for such a review may be indicated as a result of the machine having detected a predetermined degree of abnormality, such as in the cell volume, cell number, or light scatter. This may be followed by a rapid visual scan of the smear and, then, if abnormalities are suggested by that review, by a more extensive examination with reporting, among other things, of the proportion of white blood cells (WBC) made up of bands and other earlier immature forms. Greissal and colleagues determined the overall sensitivity of this process in the detection of "bandemia" by comparing the proportion of smears with an increased proportion of band forms when processed with this screening procedure, or by routine visual examination of smears of all blood samples (i.e., the degree of sensitivity of flagging a possible abnormality by the automated analyzer).
In addition to other triggers, specimens were flagged if, in addition to other findings, the machine (Beckman Coulter LH 750) detected a total WBC <...