Do You Still Report Bands?
It was not very long ago that I heard “What’s the band count?” It seemed commonplace for surgeons to decide to operate on the basis of them. ED physician assistants and
doctors waited for them, too. And don’t get me started on pediatricians.
In the laboratory, we saw (and continue to see) enormous variation in counting and reporting band counts. Some of this is caused by statistical imprecision inherent with
100-cell differentials. However, there are significant differences in perception and no happy consensus of what a “band” is:
Bands are the same size or slightly smaller than metamyelocytes. The nucleus is centrally or eccentrically placed and indented to more than half the distance from the
farthest nuclear margin. The nucleus may appear in the shape of a band, sausage, letters C or U, or may be lobulated. If lobulated, the bridge or isthmus between the lobes
must be wide enough to have two distinct parallel dark margins with light nuclear material in between.
Can’t imagine why bench techs would play the is-it-or-isn’t-it game.
Automated accuracy has been moving labs away from reporting bands in recent decades. While an elevated band count represents a “shift to the left” (immature neutrophils),
it is a less specific indicator for infection than an absolute neutrophil count. It may be secondary to inflammation, tissue damage, neoplasms, metabolic abnormalities, etc.
This and the count’s ingrained imprecision have discouraged reporting bands.
As one 2002 article points out, “the clinical folklore of
the band persists despite little mention of its diagnostic utility in current textbooks. Textbooks in internal medicine, hematology, and laboratory medicine do not recommend
band counts for the diagnosis of infection, other than to mention that neutrophilia and left-shift typically accompany infection or inflammation.”
I wonder. Are bands still a useful part of the clinical picture? They are nonspecific but still markers of a left shift. I have a sense that in large enough numbers
they are a hint that something is happening but also that reporting them will mislead some physicians.
What about your lab? Do you still report bands?
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