A Study of Renal Function in Children with Cancer

Sammanfattning: Evaluation of long-term side effects of treatment is important due to the growing number of childhood cancer survivors. How kidney function is affected over time needs to be clarified. In the first article, we investigated 247 healthy infants and children and established upper reference limits for several proteins in urine, to be used as markers for glomerular and tubular proteinuria in children with cancer. In the second article, we investigated if simpler methods could replace glomerular filtration rate (GFR) as measured by iohexol clearance in children with cancer. Examples of these methods are: serum creatinine and cystatin C, urine albumin/creatinine and IgG/creatinine, as well as three formulae for estimating GFR through serum creatinine and height. We found good correlation between GFR and all tests, except the urine protein/creatinine ratios, but the prediction of GFR was unsatisfactory with the variation being too large. In article III, we found hyperfiltration in 33 % of children at diagnosis, especially in younger children with bone marrow involvement. This was previously not described, and may be related to an increased protein turnover in children with large tumor burden. In the fourth article, long-term renal affection in 69 children with cancer was studied for up to 7 years after end of treatment. Of proposed risk factors, ifosfamide treatment with or without cisplatin, radiation and nephrectomy affected GFR the most. In 6/69 children we found persistent changes in renal function. We conclude that renal function should be monitored long-term after end of potentially nephrotoxic cancer treatment.