Infection-Related Mortality in Children Undergoing Hematopoietic Stem Cell Transplants at a Referral Center in Mexico
Authors: Pérez Rodrigo García , Aparicio Denisse Vaquera , Antolinez Valentine Jimenez , Bejarano Jose Iván Castillo , Miranda Samantha Rodríguez , Martínez Valeria Barrientos , Mariscal Alfredo Castillo , de Santos Abiel Mascareñas los 
Published: October 2024

Abstract

Background
Infections constitute a major cause of morbidity and mortality in patients undergoing hematopoietic stem cell transplantation (HSCT). In the pediatric population, infection-associated mortality rate ranging from 7% to 17% has been reported, depending on the type of HSCT, being lower in autologous transplants and higher in cases involving unrelated donors. Other factors related to HSCT that influence the clinical outcomes of these patients include the intensity of the conditioning regimen, the development of graft-versus-host disease (GVHD), cytotoxic and immunosuppressive effects of the medications used, the presence of disease activity prior to HSCT, length of hospital stay, and the use of intravascular devices, among many others.

Methods
All pediatric patients (under 16 years old) undergoing HSCT at the ‘Dr. José Eleuterio González’ University Hospital over a 55-month period (March 2019 – October 2023) were included. Clinical and epidemiological characteristics of the patients, mortality rate, and risk factors related to transplantation and infectious events (IEs) in these patients were recorded.

Results
A total of 75 patients who received HSCT were included, among them, 52 patients (69%) presented IEs. The mortality associated with IEs among these patients was 6% at day 30 and 12% at day 100, compared to 0% and 1.3% respectively in the non-IEs related deaths. The epidemiological characteristics, baseline diagnosis, donors and graft source are described in table 1. The average number of IEs in the associated mortality cases was 2.8 compared to 1.6 in the survival group. Among the mortality group (8 cases), 67% presented multiple infections and 33% single infections, with a 75% of them caused by viral infections. Regarding HSCT characteristics, in the group with IE-associated mortality, a higher proportion of haploidentical transplants, myeloablative conditioning regimens, lower use of total body irradiation, and a higher proportion of patients with detectable disease by flow cytometry prior to HSCT were observed compared to the survival group. Among non-infectious complications related to HSCT a lower frequency of acute GVHD grade I-II, a higher frequency of acute GVHD grade III-IV in the IE-associated mortality group was identified. Among the risk factors associated with hospital care, the IE-associated mortality group showed a higher use of central venous catheters, mucositis, systemic steroids, and pediatric intensive care unit stay compared to the survival group.

Conclusion
Pediatric patients undergoing HSCT present multiple risk factors that increase the incidence of infectious events and contribute to higher mortality rates. It is crucial to identify those factors related to adverse events and death to implement strategies that reduce exposure to these factors and improve the clinical outcomes.