OBJECTIVE: We compared leukocyte counts obtained by cytometric analysis and Fuchs-Rosenthal (FR) chamber counting in different proportions of lymphocytes (Lym%) suspensions and cerebrospinal fluid (CSF). DESIGN AND METHODS: UF-100 (UF) was evaluated. For preparation of cell suspensions, gradient density centrifugation method was used. RESULTS: The regression equation for UF and FR chamber counting of the cell suspensions was y=0.88x+18.8 WBC/microL (r=0.832, n=106). For a few high Lym% samples, markedly underestimated WBC counts were obtained by UF. CONCLUSIONS: Underestimated WBC count is due not to systematic error but to random error. Counts of the "other" population by UF may be useful for detection of underestimated samples.
OBJECTIVE: We compared leukocyte counts obtained by cytometric analysis and Fuchs-Rosenthal (FR) chamber counting in different proportions of lymphocytes (Lym%) suspensions and cerebrospinal fluid (CSF). DESIGN AND METHODS: UF-100 (UF) was evaluated. For preparation of cell suspensions, gradient density centrifugation method was used. RESULTS: The regression equation for UF and FR chamber counting of the cell suspensions was y=0.88x+18.8 WBC/microL (r=0.832, n=106). For a few high Lym% samples, markedly underestimated WBC counts were obtained by UF. CONCLUSIONS: Underestimated WBC count is due not to systematic error but to random error. Counts of the "other" population by UF may be useful for detection of underestimated samples.