Acute life-threatening cardiovascular toxicity with umbilical cord blood infusion: the role of dextran

Risk factors for acute kidney injury in pediatric patients after hematopoietic stem cell transplantation: a systematic review and meta-analysis

BACKGROUND

Risk factors for acute kidney injury (AKI) in pediatric patients after hematopoietic stem cell transplantation (HSCT) remain controversial.

OBJECTIVES

This study aimed to identify risk factors for AKI following HSCT in the pediatric population.

DATA SOURCES

PubMed, Embase, Web of Science, Cochrane Library, and Scopus databases were searched from inception to February 8, 2023.

STUDY ELIGIBILITY CRITERIA

Studies meeting the following criteria were included: (1) The study was a case-control, cohort study, or cross-sectional design, (2) the study was performed among pediatric and young patients aged 21 years or younger undergoing HSCT, (3) the study measured at least one related factor for AKI after pediatric HSCT, (4) the study included a sample of at least ten patients, and (5) original articles published in English in peer-reviewed scientific journals.

PARTICIPANTS AND INTERVENTIONS

Children who were undergoing pediatric HSCT.

STUDY APPRAISAL AND SYNTHESIS METHODS

We assessed the quality of the included studies and analyzed them with a random-effect model.

RESULTS

Fifteen studies with a total of 2,093 patients were included. All were cohort studies of high quality. The overall pooled incidence of AKI was 47.4% (95%CI 0.35, 0.60). We found significant associations between post-transplant AKI in pediatric patients and unrelated donor [odds ratio (OR) = 1.74, 95% confidence interval (CI) 1.09-2.79], cord blood stem cell transplantation (OR = 3.14, 95%CI 2.14-4.60), and veno-occlusive disease (VOD)/sinusoidal obstruction syndrome (SOS) (OR = 6.02, 95%CI 1.40-25.88). Other controversial factors such as myeloablative conditioning (MAC), acute graft vs. host disease (aGVHD), and the use of calcineurin inhibitors (CNI) were not found to be related to AKI after pediatric HSCT.

LIMITATIONS

Results were limited mainly by heterogeneity in the characteristics of patients and transplantation.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Posttransplant AKI in children is a common complication. Unrelated donors, cord blood stem cell transplantation, and VOD/SOS might be risk factors for AKI after pediatric HSCT. Further large-scale studies are still needed to draw firm conclusions.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42022382361 A higher resolution version of the Graphical abstract is available as Supplementary information.

Evaluation of DMSO dextrose as a suitable alternative for DMSO dextran in cord blood cryopreservation

BACKGROUND AND OBJECTIVES

Umbilical cord blood is considered an alternative source of hematopoietic stem cells. Standard banking procedures use 50/55% DMSO in dextran 40 for cryopreservation and dextran-based solutions for thawing, however, due to the potential risk of crystallization of dextran, dextran 40 approved for clinical use has become limited or unavailable. This affects cryopreservation and thawing procedures. Carbohydrates, in particular sucrose, trehalose and glucose, have been shown to be effective in reducing cell damage during dehydration and have cryoprotective potential. We aim to study a 50/55% DMSO in 5% dextrose cryopreservation solution as an alternative to DMSO dextran.

MATERIALS AND METHODS

Eighteen samples were divided into two aliquots and cryopreserved, one using standard solution and the other with DMSO dextrose experimental solution. Both aliquots were thawed and diluted with PBS or saline. Total nucleated cells counts, 7-AAD viability of CD45⁺ cells and recovery of CD34⁺ viable cells were assessed on thawed samples and compared between pair of aliquots.

RESULTS

No differences were observed in the total nucleated cells recovery between cryopreservation solutions, however, higher viability and CD34⁺ viable cells recoveries were observed using the experimental solution.

CONCLUSION

Results showed that DMSO dextrose cryopreservation solution had better results than the standard solution when thawed in an isotonic solution. This indicates that DMSO dextrose is probably a better alternative for direct infusion or when dextran thawing solutions are unavailable. Viability of CD45⁺ cells and recovery of CD34⁺ viable cells have positive correlation with engraftment, highlighting the relevance of the optimization of the cryopreservation and thawing process.

Unexpected acute renal injury after high-dose etoposide phosphate and total body irradiation in children undergoing hematopoietic stem cell transplantation

High-dose etoposide phosphate, a water-soluble prodrug of etoposide, may be used after total body irradiation (TBI) in pediatric allogeneic bone marrow transplantation for lymphoblastic leukemia. In a retrospective study of 21 children treated at the Nancy University Hospital (2000-2014), we identified unprecedentedly an unexpectedly high incidence (57%) of acute renal injury following etoposide phosphate infusion. Patients who developed renal function impairment experienced more severe mucositis but had outcomes similar to those who did not. No risk factors were identified. We speculate that the etoposide phosphate diluent, dextran 40, may have been the causative agent in these post-TBI renal toxicity cases.

Low rate of infusional toxicity after expanded cord blood transplantation

BACKGROUND AIMS

Umbilical cord blood (CB) is used with increasing frequency to restore hematopoiesis in patients with bone marrow transplant who lack a suitable human leukocyte antigen-matched donor. CB transplantation is limited by low cell doses and delays in neutrophil and platelet engraftment. CB progenitors expanded ex vivo before transplantation provide more rapid hematopoietic and immune reconstitution as well as less engraftment failure compared with unmanipulated CB. However, the safety of infusing double and ex vivo-expanded CB has not been systematically examined.

METHODS

We reviewed the immediate adverse events (AE) associated with the infusion of CB occurring within 24 hours in 137 patients enrolled in clinical CB transplant trials at the MD Anderson Cancer Center from February 2004 to May 2010. All patients received an unmanipulated CB unit followed by infusion of a second unmanipulated CB unit or a second CB unit expanded ex vivo with the use of cytokines in a liquid culture system or in mesenchymal stromal cell co-cultures.

RESULTS

A total of three grade 2 and two grade 3 infusion reactions occurred within 24 hours of CB transplantation. This resulted in an AE rate of 3.7%. The majority of AEs manifested as signs of hypertension. No association with patient age, sex, disease status, premedication, ABO compatibility or total infusion volume was observed. In summary, the incidence of infusion-related toxicities in patients who receive unmanipulated and ex vivo-expanded double CB transplantation is low.

CONCLUSIONS

We conclude that the infusion of unmanipulated followed by expanded CB products is a safe procedure associated with a low probability of inducing severe reactions.

Evaluation of a xeno-free protocol for long-term cryopreservation of cord blood cells

Cord blood is regarded as a powerful source for adult stem cells. Cord blood transplants have been used successfully to treat children and adults in autologous and allogeneic settings. Nevertheless, in many cases, the clinically relevant cell number (CD34+ cells and total leukocytes) is a limiting factor. To enable standardized cell banking and future in vitro expansion of adult stem/progenitor cells, elimination of serum, which inevitably differs from lot to lot and donor to donor, is highly desirable. Here, we demonstrate the feasibility of a xeno-free, chemically defined cryopreservation procedure for cord blood-derived cells over a period of 1 year. Cell recoveries with respect to retrieval of clinically relevant CD34+ cells, colony-forming units, and in vitro cultures of erythroid progenitor cells under standardized conditions were analyzed after 1 week or 1 year of cryopreservation and found to be very high and similar to the samples before freezing. The established xeno-free procedure is an important step toward using the full potential of adult stem cells from cord blood, enabling the elimination of serum-derived factors negatively influencing proliferation, differentiation, and survival of hematopoietic stem cells.

Lineage-specific chimerism analysis in nucleated cells, T cells and natural killer cells after myeloablative allogeneic hematopoietic stem cell transplantation

Background

Chimerism analysis is an important tool for assessing the origin of hematopoietic cells after allogeneic stem cell transplantation (allo-SCT) and can be used to detect impending graft rejection and the recurrence of underlying malignant or nonmalignant diseases.

Methods

This study included 24 patients who underwent myeloablative allo-SCT. DNA was extracted from nucleated cells (NCs), T cells, and natural killer (NK) cells, and the chimerism status of these cell fractions was determined by STR-PCR performed using an automated fluorescent DNA analyzer.

Results

Twenty-three out of the 24 patients achieved engraftment. Mixed chimerism (MC) in NCs, but not in T cells and NK cells, was significantly correlated with disease relapse. MC in all cell fractions was correlated with mortality. Ten patients (41.6%) developed extensive chronic GVHD. Six patients had MC in T cells, and 3 of them had chronic GVHD. Four patients with MC and relapse received donor lymphocyte infusion (DLI), and among them, 3 had secondary relapse. Further, the chimerism status differed among different cell lineages in 6 patients with myeloid malignancies.

Conclusion

The implications of MC in lymphocyte subsets are an important area for future research. Chimerism analysis in lineage-specific cells permits detection of relapse and facilitates the monitoring of therapeutic interventions. These results can provide the basic data for chimerism analysis after myeloablative SCT.