A method for distinguishing erythroblasts from
bacteria by automated
hematology analyzers, such as, for example, the
CELL-DYN® 4000 automated
hematology analyzer and the
CELL-DYN®
Sapphire™ automated
hematology analyzer. Bacterial cells scatter light and fluoresce differently than do red blood cells, white blood cells,
erythroblast nuclei, and platelets. Signals generated by
bacteria are distinguishable from those of erythroblasts because the signals generated by
erythroblast nuclei are sufficiently unique that
erythroblast nuclei can be distinguished from signals generated by
bacteria. Signals generated by platelets, lysed
red blood cell ghosts, and other
cell debris are blocked by the triple-trigger circuitry of the
hematology analyzer, because all of the signals generated by
noise are below the AND / OR thresholds.
Algorithm(s) in the
software of the
system detect and count signals generated by bacteria by means of the location and the shape of the signals generated by bacteria and calculate the concentration of bacteria per unit of
body fluid. In addition, certain body fluids, such as, for example,
synovial fluid, can be pretreated with a
viscosity reducing agent for a short period of time to reduce the
viscosity of the
body fluid prior to analyzing a sample of the
body fluid by an automated
hematology analyzer.