Allogeneic hematopoietic stem cell transplantation in infants is associated with significant morbidity and mortality

BACKGROUND

Infants are subjected to hematopoietic stem cell transplantation (HSCT) due to malignant and non-malignant diseases. However, specific data concerning the outcome and transplantation-related complications in infants, as a separate age group, are limited. Our aim was to evaluate the impact of infancy on the outcome, toxicity, and complications after HSCT.

METHODS

We retrospectively analyzed data of 55 infants that underwent HSCT in our unit from May 1997 until February 2020, emphasizing on the probability of overall survival (OS) and the cumulative incidence (CI) of transplantation-related mortality (TRM) and complications.

RESULTS

We report a probability of OS of 61%, a CI of TRM at day 100 and 365 post transplantation of 22% and 30%, respectively, and additionally a CI of graft failure, acute graft-versus-host disease (GvHD), and infectious complications, 18%, 44%, and 39%, respectively. No statistically significant association was detected between the above mentioned parameters and diagnosis, the use of myeloablative or non-myeloablative/reduced toxicity conditioning regimens or the type of donor.

CONCLUSIONS

We conclude that HSCT in infancy is associated with significant mortality and morbidity. This is possibly attributed to endogenous, age-related factors. More specifically, infants may be at a higher risk of toxicities due to the immaturity of developing vital organs and the deficiency of the newly adopted immune system that predisposes them to infectious complications. The development of GvHD further augments the danger of infections, in a potential vice-versa relationship. Moreover, there are few data on pharmacokinetics of chemotherapy agents, making safe and efficacious drug administration hard.

A national study of antibiotic use in Greek pediatric hematology oncology and bone marrow transplant units

OBJECTIVE

We surveyed antimicrobials used in Greek pediatric hematology-oncology (PHO) and bone marrow transplant (BMT) units before and after an intervention involving education regarding the 2017 clinical practice guidelines (CPG) for the management of febrile neutropenia in children with cancer and hematopoietic stem-cell transplant recipients.

DESIGN

Antibiotic prescribing practices were prospectively recorded between June 2016 and November 2017.

INTERVENTION

In December 2017, baseline data feedback was provided, and CPG education was provided. Prescribing practices were followed for one more year. For antibiotic stewardship, days of therapy, and length of therapy were calculated.

SETTING

Five of the 6 PHO units in Greece and the single pediatric BMT unit participated.

PARTICIPANTS

Admitted children in each unit who received the first 15 new antibiotic courses each month.

RESULTS

Administration of ≥4 antibiotics simultaneously and administration of antibiotics with overlapping activity for ≥2 days were significantly more common in PHO units in general hospitals compared to children's hospitals. Use of at least 1 antifungal was recorded in ∼47% of the patients before and after the intervention. De-escalation and/or discontinuation of antibiotics on day 6 of initial treatment increased significantly from 43% to 53.5% (P = .032). Although the number of patients requiring intensive care support for sepsis did not change, a significant drop was noted in all-cause mortality (P = .008).

CONCLUSIONS

We recorded the antibiotic prescribing practices in Greek PHO and BMT units, we achieved improved prescribing with a simple intervention, and we identified areas in need of improvement.

Insights from the Greek experience of the use of Blinatumomab in pediatric relapsed and refractory acute lymphoblastic leukemia patients

Pediatric refractory or relapsed acute lymphoblastic leukemia (ALL) poses unique therapeutic challenges, with novel immunotherapy approaches offering potential cure opportunities. In this frame, the use of Blinatumomab may induce durable remissions, serving as a successful bridge to allogeneic hematopoietic stem cell transplantation (allo-HSCT). Herein, we retrospectively summarize the Greek experience on pediatric relapsed/refractory B-cell precursor ALL patients that were treated with Blinatumomab in a compassionate, off-label setting as an effort to achieve disease clearance and proceed to allo-HSCT. In our cohort of 9 patients, 6/9 (66.7%) responded to Blinatumomab, achieving complete morphological remission (CR) after the 1st cycle, while minimal/measurable residual disease (MRD)-negativity (<10-4) after the 1st cycle was achieved in 2/2 patients (100.0%) with prior CR. A successful bridge to HSCT was feasible in 5/9 patients (55.6%). Median relapse-free survival (RFS) was 3.0 months (range 0.5-21.4 months) and median overall survival (OS) was 8.7 months (range 1.4-47.1 months) for the whole pediatric cohort. There was a trend of prolonged survival among patients who achieved MRD response after the 1st Blinatumomab administration. MRD response (defined as the >=2-log reduction of MRD value before and after Blinatumomab administration), was associated with a median RFS/OS of 7.4/7.6 months, while lack of MRD response was associated with a median RFS/OS of 0.5/3.0 months, respectively. Novel therapeutic maneuvers, in order to overcome disease resistance, i.e. increased usage of Blinatumomab dose (45 μg/m2/day), combination with donor lymphocyte infusions (DLIs), use of other immunotherapy salvage approaches (inotuzumabozogamicin), are herein discussed. Additionally, the optimal number of Blinatumomab cycles, the CD19-negative relapses and lineage switch, are also addressed. Our data although referred to a limited, however refractory or relapsed and heavily pretreated number of patients, strongly suggest that Blinatumomab may well induce sustained remissions and serve as an effective bridge to HSCT. Whether immunotherapy combined with chemotherapy can outweigh the need for subsequent allo-HSCT, if incorporated into frontline high-risk ALL therapy, remains an optimistic issue to be verified in future randomized clinical trials.

Successful long-term hematological and immunological reconstitution by autologous cord blood transplantation combined with post-transplant immunosuppression in two children with severe aplastic anemia

aUCBT is a valuable curative option in pediatric patients with refractory idiopathic SAA and no available matched sibling or unrelated donors. Experience in the use of autologous cord blood units in patients with SAA is limited and private for-profit cord blood-banking programs are controversial. We report the successful treatment of two patients with SAA, aged 15 and 24 months, with autologous cord blood combined with immunosuppression. After conditioning with 200 mg/kg cyclophosphamide and ATG, 7.5 mg/kg, 32.2 × 10⁷ /kg, and 3.8 × 10⁷ /kg autologous cord blood nucleated cells were infused, respectively. One of our patients underwent transplantation after failure of IST. Both patients received post-transplant immunosuppression with cyclosporine for 12 months. They remain disease-free 6 years post-transplantation.