Epidemiology and outcomes of invasive aspergillosis among pediatric immunocompromised patients: A 12-year single-center experience

Invasive aspergillosis (IA) remains a common cause of mortality in pediatric immunocompromised populations. Much of our knowledge of IA stems from adult literature. We conducted a retrospective evaluation of cases of proven or probable IA, defined according to the 2019 EORTC/MSG criteria, in patients with underlying immunocompromising conditions at Boston Children's Hospital from January 1, 2007 to January 1, 2019. We estimated survival curves over 12 weeks using the Kaplan-Meier method for all-cause mortality, and we used univariate Cox proportional hazards modeling to evaluate for mortality risk factors. We identified 59 cases, 29% with proven and 71% with probable IA. Pulmonary IA was the most common presentation (78%). The median age at diagnosis was 11 years (range, 0.5-28). Hematopoietic cell transplantation (HCT) was the most frequent predisposing underlying condition (41%). Among affected patients, 44.8% were neutropenic and 59.3% were lymphopenic at diagnosis. The 12-week all-cause mortality rate was 25.4%; HCT recipients comprised the majority of deaths (9/15) with a hazard ratio of 2.47 [95% CI, 0.87-6.95]. No patients with congenital immunodeficiencies (n = 8) died within 12 weeks of IA diagnosis. Other risk factors that were significantly associated with mortality included mechanical ventilation at diagnosis, intensive care unit stay, and lymphopenia; treatment with an Aspergillus-active azole was associated with decreased mortality. In conclusion, our study found that in pediatric immunocompromised hosts, IA is associated with a high 12-week all-cause mortality rate, with a particular impact on the HCT population. Lay abstract: This study explores the epidemiology, outcomes and predictors of mortality of invasive aspergillosis (IA) at a high-volume pediatric center for immunocompromised hosts. Much of our understanding of pediatric IA is extrapolated from the adult literature. Our study found that IA is associated with a high 12-week all-cause mortality rate, with a particular impact on the hematopoietic cell transplantation study cohort.