Asymptomatic kidney stones in long-term survivors of childhood acute lymphoblastic leukemia

We hypothesized an association between renal calculi and bone mineral density (BMD) deficits, shown in adults, exists in survivors of childhood acute lymphoblastic leukemia (ALL). Thus, we analyzed the associations between quantitative computed tomography (QCT)-determined renal calcifications and clinical parameters (gender, race, age at diagnosis and age at the time of QCT), BMD, treatment exposures and Tanner stage. We investigated the associations between stone formation and nutritional intake, serum and urinary calcium and creatinine levels, and urinary calcium/creatinine ratio. Exact chi(2)-test was used to compare categorical patient characteristics, and the Wilcoxon-Mann-Whitney test to compare continuous measurements. Of 424 participants, 218 (51.4%) were males; 371 (87.5%) were nonblack. Most (n = 270; 63.7%) were >= 3.5 years at ALL diagnosis. Mean (s.d.) and median (range) BMD Z-scores of the entire cohort were -0.4 (1.2) and -0.5 (-3.9 to 5.1), respectively. Nineteen participants (10 males; 10 Caucasians) had kidney stones (observed prevalence of 4.5%; 19/424) with a significant negative association between stone formation and body habitus (body mass index, P = 0.003). Stone formation was associated with treatment protocol (P = 0.009) and treatment group (0.007). Thus, kidney stones in childhood ALL survivors could herald the future deterioration of renal function and development of hypertension. Long-term follow-up imaging may be warranted in these patients to monitor for progressive morbidity.