Correlation between serum lactate dehydrogenase and stem cell mobilization

After observing a correlation between elevated serum lactate dehydrogenase (LDH) levels and good stem cell collections, retrospective data from 540 donors undergoing 650 stem cell apheresis procedures (87% autologous, 13% allogeneic) were studied to determine the correlation between preapheresis LDH levels and the absolute peripheral blood CD34+ cell count (PBCD34). PBCD34 (1-1611/mul; median 40) correlated modestly with leukocytes (0.5-118.2 x 10(9)/l; median 30.2) (r=0.16; P=0.00005) and poorly with platelets (16-660 x 10(9)/l; median 131) (r=0.02; P=0.69). The correlation between LDH (64-1664 IU/l; median 310) and PBCD34 was very strong (r=0.54; P<10(-48)). In multivariate regression analysis, serum LDH was the only factor correlating significantly with PBCD34. The correlation between serum LDH and PBCD34 was strong on the first day of collection (n=517; r=0.53; P<10(-37)), weakened on the second day (n=74; r=0.37; P=0.0009) and disappeared beyond day 2 (n=59; r=0.09; P=0.49). PBCD34 was significantly higher (median 53 versus median 11; P<0.00001) when LDH was elevated (n=511) compared to when LDH was normal (n=139). The relationship between serum LDH and PBCD34 was strong for autologous (r=0.54) as well as for allogeneic (r=0.41) collections. Our data suggest that it is reasonable to assume good stem cell mobilization and start apheresis if the LDH is elevated.