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Peripheral Blood Progenitor Cell Collection by Large-Volume Leukapheresis in Low-Weight Children

1998; Mary Ann Liebert, Inc.; Volume: 7; Issue: 1 Linguagem: Inglês

10.1089/scd.1.1998.7.63

2168-6556

Miguel Ángel Díaz, Adrián Alegre, Ana Benito, M. Villa, Luís Madero,

Hematological disorders and diagnostics

Large-volume leukapheresis (LVL), defined as the processing of at least three blood volumes in a single session for peripheral blood progenitor cell (PBPC) collection, was performed in 32 small children weighing ≤25 kg, aged 10 months to 8 years, with a variety of malignancies. Harvesting of PBPC was started after 4 days of cytokine (G-CSF, 12 μg/kg s.c.) alone. Procedures were performed using a continuous flow blood cell separator (COBE Spectra). The automated program of lymphocytapheresis was modified to achieve a collection rate of 0.9 ml/min. The extracorporeal line was primed with a unit of a packed red blood cells before the procedure. Acid citrate dextrose (ACD) was used as anticoagulant with an ACD inlet ratio of 1:14 and an ACD infusion rate of 1.1 ml/min/L of total blood volume. The inlet flow ranged between 6 and 35 ml/min (median 20 ml/min). A total of 37 apheresis procedures were performed (median 1, range 1-3). In 84% of patients, a single apheresis yields the minimum number of PBPC cells required for transplantation. No consistent side effects were observed, and LVL was well tolerated by children. A median of 7.7 x 108 kg MNC, 5.4 x 106/kg CD34+, and 6.2 x 104/kg CFU-GM per apheresis were harvested. Patients with neuroblastoma had a significantly lower yield than other patients. To date, 27 patients have been transplanted after myeloablative treatment, and rapid and sustained engraftment was achieved in all cases. The number of CD34+ cells infused was highly correlated with engraftment kinetics. LVL can be safely and easily performed in small children, allowing adequate PBPC collection for transplantation with rapid hematologic recovery.