Large volume leukapheresis in small children: safety profile and variables affecting peripheral blood progenitor cell collection.

Large volume leukapheresis (LVL) has been proposed as a simplified single-apheresis approach to collect the target number of CD34(+) cells. We retrospectively analyzed results of LVL in cytokine-mobilized patients weighing less than 20 kg to evaluate adverse events and variables affecting the yield. The only major adverse event recorded was transient and reversible systolic hypotension (three episodes). All the other adverse events were mild and did not require treatment. In multivariate analysis leukocyte count (P=0.001) and younger age (P=0.009) affected the CD34(+) cell number in the peripheral blood before apheresis. The number of CD34(+) cells before the apheresis was the only variable affecting CD34(+) cell yield in multivariate analysis (P=0.0001). In all, 77% of patients achieved the target CD34(+) cell dose of 2 x 10(6)/kg in their first apheresis. Recruitment was seen in 72% of the procedures, and this was related to the total blood volume processed (P=0.0005).