Association of bone mineral density with incidental renal stone in long-term survivors of childhood acute lymphoblastic leukemia

Bone mineral density surveillance for childhood, adolescent, and young adult cancer survivors: evidence-based recommendations from the International Late Effects of Childhood Cancer Guideline Harmonization Group

Childhood, adolescent, and young adult cancer survivors are at increased risk of reduced bone mineral density. Clinical practice surveillance guidelines are important for timely diagnosis and treatment of these survivors, which could improve bone mineral density parameters and prevent fragility fractures. Discordances across current late effects guidelines necessitated international harmonisation of recommendations for bone mineral density surveillance. The International Late Effects of Childhood Cancer Guideline Harmonization Group therefore established a panel of 36 experts from ten countries, representing a range of relevant medical specialties. The evidence of risk factors for very low and low bone mineral density and fractures, surveillance modality, timing of bone mineral density surveillance, and treatment of very low and low bone mineral density were evaluated and critically appraised, and harmonised recommendations for childhood, adolescent, and young adult cancer survivors were formulated. We graded the recommendations based on the quality of evidence and balance between potential benefits and harms. Bone mineral density surveillance is recommended for survivors treated with cranial or craniospinal radiotherapy and is reasonable for survivors treated with total body irradiation. Due to insufficient evidence, no recommendation can be formulated for or against bone mineral density surveillance for survivors treated with corticosteroids. This surveillance decision should be made by the survivor and health-care provider together, after careful consideration of the potential harms and benefits and additional risk factors. We recommend to carry out bone mineral density surveillance using dual-energy x-ray absorptiometry at entry into long-term follow-up, and if normal (Z-score > -1), repeat when the survivor is aged 25 years. Between these measurements and thereafter, surveillance should be done as clinically indicated. These recommendations facilitate evidence-based care for childhood, adolescent, and young adult cancer survivors internationally.

Induced urinary crystal formation as an analytical strategy for the prediction and monitoring of urolithiasis and other metabolism-related disorders

Crystal formation reflects the entire composition of the surrounding solution. In case of urolithiasis, induced crystal formation in native urine has led to the development of the Bonn-Risk-Index (BRI), a valuable tool to quantify an individual's risk of calcium oxalate urolithiasis. If the progression of a disease is associated with characteristic changes in the activities of urinary components, this leads to an altered urinary crystallisation capacity. Therefore, the results of induced urinary crystal formation can be used to detect and monitor any disease linked to the altered urinary composition. Since crystal formation inherently takes into account the entire urinary composition, the influence of the disease on individual urinary parameters does not have to be known in order to monitor the consequent pathologic alterations. In this paper, we review the background of urinary crystal formation analysis and describe its established application in urolithiasis monitoring as well as potential further fields of clinical application.

Nephrolithiasis in pediatric hematopoietic cell transplantation with up to 40 years of follow-up

BACKGROUND

Kidney stones have been reported to occur after childhood cancer, but little is known about kidney stones in children following hematopoietic cell transplantation (HCT). The objective of this retrospective study was to determine risk factors for the development of kidney stones and to describe the prevalence among survivors.

PROCEDURE

The study included 1,343 childhood HCT patients. Mean follow-up was 15.8 (1.0-40.0) years. Patients were treated with total body irradiation (TBI) (n = 948) or non-TBI regimens. Methotrexate (MTX) for acute graft-versus-host disease (GVHD) prophylaxis was given as long-course (n = 360), short-course (n = 626), or none (n = 357). Prednisone for chronic GVHD therapy was received by 525 patients. Multivariate Cox regression models were used to estimate the hazard ratio (HR) of risk factors associated with kidney stones.

RESULTS

Kidney stones developed in 51 patients, a median of 9.9 (0.2-29.4) years after first HCT, with a 30-year cumulative incidence of 7.4%. Risk factors associated with kidney stones were TBI (HR = 2.2; P = 0.03), age at HCT (12-18 vs. <6 years, HR = 2.7; P = 0.01), MTX (long vs. none, HR = 3.6; P = 0.02), and prednisone (HR = 2.2; P = 0.008). Among 868 survivors, the prevalence of a history of kidney stones was 4.7%.

CONCLUSIONS

Survivors of childhood HCT have an increased risk of developing kidney stones.