Increased overall and bacterial infections following myeloablative allogeneic HCT for patients with AML in CR1

Abstract

Presumably, reduced-intensity/nonmyeloablative conditioning (RIC/NMA) for allogeneic hematopoietic cell transplantation (alloHCT) results in reduced infections compared with myeloablative conditioning (MAC) regimens; however, published evidence is limited. In this Center for International Blood and Marrow Transplant Research study, 1755 patients (aged ≥40 years) with acute myeloid leukemia in first complete remission were evaluated for infections occurring within 100 days after T-cell replete alloHCT. Patients receiving RIC/NMA (n = 777) compared with those receiving MAC (n = 978) were older and underwent transplantation more recently; however, the groups were similar regarding Karnofsky performance score, HCT-comorbidity index, and cytogenetic risk. One or more infections occurred in 1045 (59.5%) patients (MAC, 595 [61%]; RIC/NMA, 450 [58%]; P = .21) by day 100. The median time to initial infection after MAC conditioning occurred earlier (MAC, 15 days [range, <1-99 days]; RIC/NMA, 21 days [range, <1-100 days]; P < .0001). Moreover, the rate of any infection per patient-days at risk in the first 100 days (infection density) after alloHCTwas greater for the MAC cohort (1.21; 95% CI, 1.11-1.32; P