Urolithiasis in an acute lymphoblastic leukemia child during induction chemotherapy

Management of Pediatric Urolithiasis in an Italian Tertiary Referral Center: A Retrospective Analysis

Background and Objectives: In recent years, the prevalence of pediatric urolithiasis has increased in North America and Western countries, though it is endemic in developing countries. The aim of this study is to describe the experience of a tertiary pediatric referral center in the surgical management of pediatric urolithiasis. Materials and Methods: We retrospectively reviewed the experience of patients ≤ 16 years old affected by urinary stones who underwent surgery. Results: From April 2021 to September 2023, 31 pediatric patients underwent surgical procedures for stone diseases at our department: 13 preschool-aged (1-5 years) and 18 school-aged (6-16 years) children. During this period, 12 URSs, 17 RIRSs, and 2 PCNLs were recorded. Five patients had residual fragments at first, so three of them underwent a second endourological lithotripsy (2 RIRSs and 1 URS). Complete clearance was finally achieved in 27 patients. The stone composition was evaluated in 25 cases. Conclusions: Numerous innovations in the surgical treatment of pediatric urolithiasis have resulted from the development of smaller devices and new technology. Our results show how, in experienced centers, retrograde and percutaneous lithotripsy are safe and effective procedures for use in pediatric populations.

Drug-Induced Urolithiasis in Pediatric Patients

Drug-induced nephrolithiasis is a rare condition in children. The involved drugs may be divided into two different categories according to the mechanism involved in calculi formation. The first one includes poorly soluble drugs that favor the crystallization and calculi formation. The second category includes drugs that enhance calculi formation through their metabolic effects. The diagnosis of these specific calculi depends on a detailed medical history, associated comorbidities and the patient's history of drug consumption. There are several risk factors associated with drug-induced stones, such as high dose of consumed drugs and long duration of treatment. Moreover, there are some specific risk factors, including urinary pH and the amount of fluid consumed by children. There are limited data regarding pediatric lithogenic drugs, and hence, our aim was to perform a comprehensive review of the literature to summarize these drugs and identify the possible mechanisms involved in calculi formation and discuss the management and preventive measures for these calculi.

What is the incidence of kidney stones after chemotherapy in patients with lymphoproliferative or myeloproliferative disorders?

INTRODUCTION

This study describes the incidence and risk factors of de novo nephrolithiasis among patients with lymphoproliferative or myeloproliferative diseases who have undergone chemotherapy.

MATERIALS AND METHODS

From 2001 to 2011, patients with lymphoproliferative or myeloproliferative disorders treated with chemotherapy were retrospectively identified. The incidence of image proven nephrolithiasis after chemotherapy was determined. Demographic and clinical variables were recorded. Patients with a history of nephrolithiasis prior to chemotherapy were excluded. The primary outcome was incidence of nephrolithiasis, and secondary outcomes were risk factors predictive of de novo stone. Comparative statistics were used to compare demographic and disease specific variables for patients who developed de novo stones versus those who did not.

RESULTS

A total of 1,316 patients were identified and the incidence of de novo nephrolithiasis was 5.5% (72/1316; symptomatic stones 1.8% 24/1316). Among patients with nephrolithiasis, 72.2% had lymphoproliferative disorders, 27.8% had myeloproliferative disorders, and 25% utilized allopurinol. The median urinary pH was 5.5, and the mean serum uric acid, calcium, potassium and phosphorus levels were 7.5, 9.6, 4.3, and 3.8 mg/dL, respectively. In univariate analysis, mean uric acid (p=0.013), calcium (p<0.001)), and potassium (p=0.039) levels were higher in stone formers. Diabetes mellitus (p<0.001), hypertension (p=0.003), and hyperlipidemia (p<0.001) were more common in stone formers. In multivariate analysis, diabetes mellitus, hyperuricemia, and hypercalcemia predicted stone.

CONCLUSIONS

We report the incidence of de novo nephrolithiasis in patients who have undergone chemotherapy. Diabetes mellitus, hyperuricemia, and hypercalcemia are patient-specific risk factors that increase the odds of developing an upper tract stone following chemotherapy.

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.