BasophilsBasophil count
The rarest white cells, involved in allergic and inflammatory reactions.
Basophils are the least numerous white blood cells. They carry granules of histamine and other mediators, which they release during allergic and inflammatory responses.
It matters relatively little on a routine panel, precisely because the numbers are so small that ordinary variation dominates. A persistently raised count is occasionally a clue to a marrow disorder.
In practice a basophil result outside the range on a single count, with everything else normal, is usually not pursued on its own.