1591. The Impact of Pretransplant Respiratory Virus Infection in Pediatric Hematopoietic Cell Transplant Recipients

Abstract Background Respiratory virus infections (RVIs) in adult hematopoietic cell transplant (HCT) candidates have been shown to impact posttransplant outcomes; however, there are few studies pediatric patients. We sought evaluate the role of specific viruses and location viral infection on post HCT outcomes. Methods evaluated allogeneic recipients receiving myeloablative conditioning from 3/2010–3/2018. All patients had a multiplex PCR for RVIs prior HCT, regardless symptoms. Delaying was recommended when feasible RSV, parainfluenza, metapneumovirus, adenovirus, influenza, but not routinely human rhinovirus (HRV) endemic coronaviruses. utilized Cox proportional hazards models progression lower respiratory disease (LRD) linear regression days alive out hospital (DAOH) by 100 HCT. Results Of 310 conditioning, 133 (43%) were positive RVI before Baseline characteristics notable differences age, recipient CMV serostatus, delayed (Table 1). The most common HRV (97, 73%) 81 (61%) symptomatic at time detection. Most URI (92%) 11 LRD (3 proven, 8 possible). In univariate analysis, as type associated with fewer DAOH preHCT (with without symptoms) trended towards (Figure 1a). When adjusted lymphocyte count, source, regimen, both showed trend DAOH, no significant association found 1b,c). Twenty progressed after same RVI; factors, including delay transplant, reduced LRD. (A) Univariable (B) Multivariable type, (C) symptom composite. Conclusion this single center study, increased hospitalization multivariate models. Larger multicenter needed provide timely evaluation adequate statistical power definitively determine versus treatment strategies. Disclosures Yae-Jean Kim, MD, PhD, Janssen: Grant/Research Support|Korean Society Pediatric Infectious Diseases: Support|Ministry Trade, Industry Energy: Support|MSD: Support chikara Ogimi, Horiba: payment lecture Michael J. Boeckh, MD Allovir: Advisor/Consultant|Amazon: Support|Ansun Biopharma: Support|EvrysBio: Advisor/Consultant|Gates Ventures: Support|Gilead Sciences: Advisor/Consultant|Gilead Support|GlaxoSmithKline: Advisor/Consultant|GlaxoSmithKline: Support|Helocyte: Advisor/Consultant|Janssen: Support|Kyorin Pharmaceuticals: Advisor/Consultant|Merck: Support|Moderna: Advisor/Consultant|Moderna: Support|Regeneron: Support|ReViral: Advisor/Consultant|Symbio: Advisor/Consultant|Takeda: Support|Vir Biotechnology: Advisor/Consultant|Vir Janet A. Englund, Astra Zeneca: Advisor/Consultant|Astra Support|Meissa Vaccine: Support|Pfizer: Support|SanofiPasteur: Advisor/Consultant Alpana Waghmare, Support|Devarra Therapeutics: DSMB|Kyorin Pharmaceutical: Advisor/Consultant|Pfizer: Support|Vir/GSK: Support.