Diagnosis of infective and inflammatory disorders by flow cytometric analysis of blood neutrophils.

The utility of neutrophil parameters provided by two flow cytometric hematologic analyzers (the H-1 and H6000, Technicon Instruments Corporation, Tarrytown, NY) was investigated for the diagnosis of infective and/or inflammatory disorders. The test population of 156 hospital patients was selected on the basis of a blood culture request. Positivity or negativity for infective and/or inflammatory disease was inferred from chart review. The parameters evaluated included the absolute neutrophil count, the lobularity index, and the left shift flag from the H-1, the percentage of high peroxidase cells from the H6000, the routine laboratory band count, and a reference band count. Significant intercorrelations were observed between these parameters. The diagnostic performance of the routine laboratory band count was significantly inferior to that of all other parameters. At equivalent points on their receiver operating characteristic curves, the diagnostic efficiencies of the remaining tests ranged from 61.5% for the lobularity index to 67% for the left shift flag and the percentage of high peroxidase cells. These differences were not significant statistically.