Safety and efficacy of autologous mononuclear cell and stem cell apheresis in very low‐weight children—Experience at a single center

Abstract

Background: Apheresis in children with low body weight is technically limited by their tolerance of the extracorporeal blood volume. Study design and methods: This paper presents a single-center experience with 23 procedures in 12 children with weights between 5.2 and 9.5 kg using the Spectra Optia mononuclear cell (MNC) protocol with blood priming. Results: The average procedure duration was 158 minutes, and the median processed blood volume was 316 mL/kg. The white blood cell (WBC), platelet (PLT), and hemoglobin (HGB) values showed a downward trend with increased volume of processed blood. The post-apheresis HGB concentration was increased in all procedures due to initial priming with packed red blood cells (PRBCs), but this effect disappeared at a level of~400 mL of processed blood/kg. The median volume of the cellular product was 36 mL, the WBC count was 153 K/μL, the hematocrit (HCT) was 1.5%, the PLT count was 602 K/μL, the WBC collection efficacy (CE2) was 13.2%, and the PLT CE2 was 9.5%. The median CD34+ CE2 was 28%, and interpolation of the CD34+ CE2 yielded a Y-intercept value of 32%.Higher pre-collection CD34+ counts resulted in higher CD34+ yields. No correlation was found between the pre-collection CD34+ results and CD34+ CE2. CONCLUSION: The analyzed data demonstrated the feasibility and safety of apheresis in very low-weight children. The laboratory abnormalities were asymptomatic and citrate toxicity was mild. Visual control of clogging with manual adjustment of the citrate infusion rate is important to reduce exposure to citrate. K E Y W O R D S apheresis, low-weight, pediatric

Prevention of hypokalaemia and hypomagnesaemia following peripheral stem cell collection – a prospective cohort study

“…Also for magnesium, a decline across both procedure types and patient groups has been reported. The ionized magnesium dropped by 30–56% [5, 8–12], whereas the effect on total magnesium was significantly smaller (<12%) [5, 8, 9, 12]. In the present study, only plasma total magnesium was measured, and an approximate 16% decline was seen in subjects not receiving magnesium prophylaxis.…”

Peripheral blood stem cells collection by apheresis in very low‐weight children with malignant diseases—A single center experience

“…The small number of patients and apheresis sessions in our sample does not allow us to establish reliable predictors of collection efficacy. Factors such as the underlying pathology, the presence of metastases, the chemotherapy regimen and patients' weight may be potential predictors, 2,20,[24][25][26] but prospective studies with a larger sample size are needed to address this issue. Multicenter studies, involving several countries, could possibly overcome the paucity of includable patients.…”

“…Hematopoietic stem cell transplantation (HSCT) involves hematological and immunological reconstitution and is a therapeutic option in the treatment of children with malignant and non-malignant diseases. 1,2 The challenge of pediatric peripheral blood stem cell (PBSC) collection is multifactorial. The increased occurrence of side effects and the greater complexity associated with extracorporeal blood volume (EBV), venous access placement and management of anticoagulation are some of the main players in this conundrum.…”

“…Within this group, low-weight children pose a bigger challenge once there is a small number of patients and, therefore, little experience. 2 This work thus aims to increase the current knowledge in this area, presenting the 15-year experience of a Portuguese center in PBSC collection in very low-weight children.…”

“…Hematopoietic stem cell transplantation (HSCT) involves hematological and immunological reconstitution and is a therapeutic option in the treatment of children with malignant and non‐malignant diseases 1,2 …”