Comparison of CD34-positive cells enumeration using ADAMII image-based fluorescence cell counter with fluorescence flow cytometry

Objectives The gold standard method of CD34+ cells counting is based on fluorescence flow cytometry. Previous studies showed that image-based immunofluorescence cell counting could be suitable for enumerating CD34+ cells. We compared CD34+ cell counting with both methods using samples obtained from mobilized peripheral blood (MPB) and leukapheresis bags (LB). Methods Samples were obtained from MPB (n=74) and LBs (n=41). Flow cytometry CD34+ cell enumeration was performed according to the ISHAGE single-platform protocol. CD34+ cell enumeration with ADAMII device was performed following manufacturer’s instructions. Spearman rank correlation coefficient (r s ) and bias study were performed. Bland–Altman analysis was performed to plot the bias. Results A statistically significant strong positive linear correlation was observed between both methods (r s >0.9 and p<0.001). In the bias analysis, CD34+ cell count (×10 3 /mL) was statistically higher with flow cytometry method when compared with ADAMII method (95 % CI of the mean bias from 49.86 to 287.9) in LB samples but CD34+ cell count was not statistically higher with flow cytometry method when compared with ADAMII method (95 % CI of the mean bias from −2.20 to 5.25) in MPB samples. Conclusions ADAMII showed a statistically significant strong positive linear correlation with flow cytometry when analyzing CD34+ cell counts obtained from MPB and LB samples. In the bias study, however, CD34+ cell counts were statistically higher with flow cytometry when compared with ADAMII method in samples obtained from LBs. Future studies will be necessary to examine the possibility of inappropriate clinical decisions resulting from an inaccurate CD34+ cell count.