Acute Kidney Injury and the Risk of Mortality in Children Undergoing Hematopoietic Stem Cell Transplantation

Abstract

Acute kidney injury (AKI) is a well-documented complication of pediatric hematopoietic stem cell transplantation (HSCT). Dialysis after HSCT is associated with a lower overall survival (OS); however, the association between less severe AKI and OS is unclear. We retrospectively studied 205 consecutive pediatric HSCT patients to determine the incidence and impact of all stages of AKI on OS in pediatric HSCT recipients. We used the peak pRIFLE grade during the first 100 days to classify AKI (ie, R = risk, I = injury, F = failure, L = loss of function, E = end-stage renal disease) and used the modified Schwartz formula to estimate glomerular filtration rate. AKI was observed in 173 of 205 patients (84%). The 1-year OS rate decreased significantly with an increasing severity of pRIFLE grades (P < .01). There was no difference in the OS between patients without AKI and the R/I group. Regardless of the dialysis status, stages F/L/E had significantly lower rates of OS compared with patients without AKI or R/I (P < .01). There was no difference in OS among patients with dialysis and F/L/E without dialysis (P = .65). Stages F/L/E predicted mortality independent of acute graft-versus-host disease, gender, and malignancy. The OS of children after HSCT decreases significantly with an increasing severity of AKI within the first 100 days post-transplant. Although our data did not show an increased risk of mortality with stages R/I, stages F/L/E predicted mortality regardless of dialysis. Prevention and minimization of AKI may improve survival after pediatric HSCT.

Keywords: Acute kidney injury; Chronic kidney disease; Mortality; Pediatric hematopoietic stem cell transplantation.

Figure 1

1-year OS by severity of acute kidney injury Abbreviations: AKI – acute kidney injury; R/I – risk and injury; F/L/E – failure, loss and end-stage renal disease P value of < 0.01 indicates that at least one of the groups is statistically different from others Pairwise comparison: No AKI versus R/I – p value 0.22 F/L/E with dialysis versus F/L/E without dialysis – p value 0.65 No AKI plus R/I versus F/L/E with and without dialysis – p value < 0.01

Figure 2

1-year mortality rate by the lowest estimated glomerular filtration rate within the first 100 days posttransplant

Figure 3

1-year mortality rate by the lowest estimated glomerular filtration rate within the first 100 days posttransplant (Allogeneic recipients)

Figure 4

1-year mortality rate by the lowest estimated glomerular filtration rate within the first 100 days posttransplant (Autologous recipients)