Renal function, evaluated as glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), was investigated in 187 pediatric patients who underwent allogeneic (n ¼ 169) or autologous bone marrow transplantation (BMT). Allogeneic BMT patients were divided into three groups: hematological malignancies, aplastic anemia and non-malignant diseases, whereas autologous patients constituted a fourth group. A total of 64% received total body irradiation (TBI) as conditioning therapy, and 50 healthy children served as controls. GFR and ERPF were normal before transplantation. After 1 year, both GFR and ERPF were significantly reduced. GFR had recovered slightly after 3 years and remained stable thereafter. Recovery in ERPF was not apparent. Renal impairment was found in 41% of patients at 1 year, in 31% at 3 years and in 11% 7 years after BMT. Patients with hematological malignancies had lower GFRs than patients with non-malignant diseases at all time points. The most important risk factor as regards chronic renal impairment was TBI. Type of donor, cyclophosphamide (CY), or acute graft-versus-host disease (GVHD) did not seem to contribute to the development of chronic renal impairment. We suggest that tests of renal function should be included in long-term followup after BMT.

Our results show that HD-MTX treatment significantly decreases GFR and may cause albuminuria in pediatric cancer patients several years after treatment. Long-term renal follow-up of these patients is therefore important.

Pediatric BT survivors had significant neurocognitive consequences. This, together with the considerable risk for endocrine morbidity, will motivate us to organize systematic follow-up procedures for pediatric BT survivors.