(758) Primary Immune Deficiency and Hematopoietic Cell Transplant in U.S. Children From 2000 to 2019

Introduction: Primary Immune deficiency disorders (PID) in pediatrics when underrecognized or left untreated have
high morbidity and mortality. Transplantation [Bone Marrow (BMT), Stem cell (SCT), or cord blood (CBT)]
can be curative. This study aimed to describe the prevalence and outcomes of transplantation and their
trends in patients with PID.

Methods: A retrospective analysis of Kids’ Inpatient Database from 2000 to 2019 was performed. Hospitalized
children < 20 years were selected using ICD 9 and 10 diagnosis and procedure codes. Univariate and
multivariable analyses were performed for inferential statistics. Trend analysis was performed to
evaluate the prevalence of PID in all hospital discharges and the rate of transplantation among PID
discharges for the study duration.

Results: Of 48,419,107 hospitalized children from 2000-2019, 54,154 had PID (prevalence: 1.1 per 1000
discharges and 8.9 per 100,000 population). Out of these PID cases, 1133 (2%) children received
transplantation. During the study period, the prevalence of PID increased from 0.3 to 2.8 per 1000
(p < 0.001) and the rate of transplantation increased from 0.8% to 2.1% (p < 0.001). The majority of
children who underwent transplantation were Toddlers (25.7%). The types of transplants performed
included BMT (33.1%), SCT (54.1%), and CBT (14.9%), and types of immune disorders included, B cell
disorders (49.9%), T cell disorders (16.1%), Combined immunodeficiency (4.5%), neutrophil disorders
(2.2%), and unspecified (27.3%). The overall mortality rate for transplanted patients was 7.7%. There
was a decreasing trend in mortality in children who were transplanted (p=0.0004). On regression
analysis the mortality was higher with the need for invasive mechanical ventilation (IMV) (50.9%,
OR=25.9, 95%CI: 14.7-45.5) and with the presence of septic shock (32.8%, OR=3.8, 95%CI: 1.5-9.8),
fungal infection (18.5%, OR=2.2, 95%CI: 1.1-4.2), and graft vs. host disease (15.0%, OR=2.1, 95%CI: 1.2-
45.5).

Conclusions: This nationwide study reveals an increase in transplantation rates and a simultaneous decrease in
transplant-associated hospital mortality among children with PID from 2000 to 2019. We report various
types of PID that underwent transplantation during this time, alongside identifying the factors
associated with mortality.