Renal function in late survivors of Iranian children with cancer: Single centre experience

Context: One of the side-effects of chemotherapy is nephrotoxicity, whose incidence rate has reportedly been higher in pediatrics. Early diagnosis of renal dysfunction may decrease the morbidity in those with partial or complete remission by avoiding nephrotoxic agents and promoting regular follow-up.
Aims: We studied the frequency of renal dysfunction in pediatric patients whose therapy was completed regardless of the type of chemotherapy.
Settings and Design: Prospective cross sectional study in Hematoncology department of children′s hospital.
Materials and Methods:0 One hundred and eight pediatric cancer patients (44 females, 64 males), who were at least one year off therapy, enrolled in the study from 2003 to 2005. Demographic data, mean dosages of anticancer drugs, history of other nephrotoxic agents, nephrectomy, radiotherapy and acute renal failure were recorded. Fasting blood and urine samples were collected to calculate fractional excretion of magnesium, calcium, phosphate, urine protein to urine creatinine ratio, creatinine clearance (using Schwartz formula), urine analysis, urine osmolality and blood gas analysis.
Statistical analysis used: T-test, Chi square and binary logistic regression were used to compare means, frequency and correlation respectively. P values < 0.05 were considered significant.
Results: Renal dysfunction was seen in 25.2% of cases. These abnormalities included hypercalciuria (7.2%), phosphaturia (13.5%), magnesuria (3.6%), glomerular filtration rate less than 90 ml/min (7.5%), metabolic acidosis (3%), metabolic alkalosis (10%), urinary concentration defect (19%), proteinuria (7.2%), glycosuria (2%), microscopic hematuria (4%), sterile pyuria (6%), and hypertension (8%). We found only Procarbazin as an independent variable of nephrotoxicity (P< 0.05).
Conclusions: Mild to moderate tubular dysfunction has been observed in the survivors of cancer disease.

Keywords
Cancer, chemotherapy, late survivors, nephrotoxicity, tubular dysfunction