Peripheral blood stem cell apheresis in low-weight children: A single centre study

Abstract

Peripheral blood stem cell transplantation (PBSCT) is now widely used in both malignant and non-malignant hematologic diseases as a treatment strategy. Using this approach, a controversial group of donors is children weighing 20 kg or less. The aim of this study was to evaluate results of allogeneic and autologous PBSCT and also the efficacy of our suggested alternative method for a custom prime in cell harvesting of this group. All the participants' demographic and laboratory data were collected before apheresis. A total of 37 individuals participated in this study of which 12 and 25 of them were categorized in autologous and allogeneic groups respectively. For the apheresis procedure, a central venous access was used as well as the custom prime method with some changes. Apheresis details, as well as CD34 and CD3 cell counts in the allogeneic and autologous groups, were calculated. In this study, 91.9% (N = 34) of all individuals achieved the minimal amount of cells for PBSCT (2 × 10⁶ CD34⁺ cells/kg) in one session. On the other hand, 12% (N = 3) of donors in the allogeneic group achieved the minimal threshold in 2 apheresis sessions. During the leukapheresis a total processed blood volume/total blood volume ratio (TPBV/TBV) was calculated as 4.64 ± 1.06 and 5.18 ± 0.73 fold in the allogeneic and autologous groups respectively. The mean of harvested CD34 cells in allogeneic and autologous groups was 5.28 ± 3.47 × 10⁶ and 3.57 ± 2.9 × 10⁶ cells/kg respectively. Likewise, in the allogeneic group, the mean of the harvested CD3 cell count was 339 ± 141 × 10⁶/kg. Also, the median day of white blood cell (WBC) engraftment was 14 and 13 for allogeneic and autologous groups respectively. Furthermore, the median day of platelet engraftment was 19.5 for both allogeneic and autologous groups. Among the recipients of the allogeneic group, acute graft versus host disease (aGVHD) was detected in 56% (N = 14) of patients and this was also correct for chronic GVHD. Taken together, it was shown, despite the probable complications of peripheral blood stem cell apheresis in donors weighing less than 20 kg; that it is possible to perform this procedure without any complication during the leukapheresis.

Keywords: Apheresis; Low weight children; Peripheral blood stem cell; Transplantation.