Pretransplant predictors and posttransplant sequels of acute kidney injury after allogeneic stem cell transplantation.

Acute kidney injury (AKI) is a common complication after allogeneic stem cell transplantation (SCT). Although various risk factors for AKI have been reported, the influence of pretransplant comorbidity on the incidence of AKI has not been well investigated. We performed a retrospective analysis of 207 consecutive patients undergoing myeloablative or nonmyeloablative SCT between 2001 and 2009, using the hematopoietic cell transplantation-specific comorbidity index (HCT-CI) as a representative of pretransplant comorbidities. According to Risk, Injury, Failure, Loss, and End-stage kidney disease (RIFLE) criteria, 158 patients (76.3%) developed AKI, and 92 patients (44.4%) developed severe AKI (RIFLE class I or class F) within 100 days after SCT. The cumulative incidence of severe AKI within 100 days in patients with an HCT-CI score 0, 1-2, and ≥3 was 21.3%, 48.8%, and 73.9%, respectively. In multivariate analysis, the HCT-CI was independently associated with severe AKI (HCT-CI 1-2: adjusted hazard ratio [HR] 2.42, P < .01; HCT-CI ≥3: adjusted HR 4.69, P < .01). In a landmark analysis, patients with severe AKI had a lower 3-year overall survival (OS) (39.3% versus 61.4%, P < .01), and a higher 3-year nonrelapse mortality (NRM) (40.8% versus 5.6%, P < .01) than those without AKI. Multivariate analysis showed that severe AKI was a significant risk factor for worse OS (HR: 2.10, P = .01) and NRM (HR: 6.15, P < .01). Thus, it is important to assess the HCT-CI to predict the incidence of AKI, which is a strong indicator of worse prognosis after SCT.