BACKGROUND: We analyzed late fatal infections (LFI) in allogeneic stem cell transplant (HCT) recipients reported to the Center for International Blood and Marrow Transplant Research.
METHODS: We analyzed the incidence, infection types and risk factors contributing to LFI in 10336 adult and 5088 pediatric subjects surviving ≥2 years after first HCT without relapse.
RESULTS: Among 2245 adult and 377 pediatric subjects who died, infections were a primary or contributory cause of death in 687(31%) and 110(29%) subjects, respectively. At 12 years post-HCT cumulative incidence of LFIs was 6.4 % (95% confidence interval[CI]:5.8-7.0%) in adults as compared with 1.8% (95%CI:1.4-2.3%) in pediatric subjects, p<0.001. In adults, the two most significant risks for developing LFI were increasing age (20-39, 40-54 and ≥ 55 vs 18-19 years) with hazard ratio (HR) of 3.12 (95%CI:1.33-7.32), 3.86 (95%CI:1.66-8.95) and 5.49 (95%CI:2.32-12.99) and a history of chronic GVHD (cGVHD) with ongoing immunosuppression 2 years post-HCT as compared to no history of GVHD with HR 3.87 (95%CI:2.59-5.78), respectively. In pediatric subjects, the three most significant risks for developing LFI were a history of cGVHD with (HR 9.49, 95%CI:4.39-20.51) or without (HR 2.7,95%CI:1.05-7.43) ongoing immunosuppression 2 years post-HCT as compared to no history of GVHD, diagnosis of inherited abnormalities of erythrocyte function as compared to diagnosis of acute myeloid leukemia (AML) (HR 2.30, 95%CI:1.19-4.42) and age >10 years (HR 1.92, 95%CI:1.15-3.2).
CONCLUSION: This study emphasizes the importance of continued vigilance for late infections after HCT and support strategies aimed to decrease the risk of cGVHD.