Nonskeletal and skeletal effects of high doses versus low doses of vitamin D3 in renal transplant recipients: Results of the VITALE (VITamin D supplementation in renAL transplant recipients) study, a randomized clinical trial.

Vitamin D sufficiency is associated with a reduced risk of fractures, diabetes mellitus, cardiovascular events, and cancers, which are frequent complications after renal transplantation. The VITALE (VITamin D supplementation in renAL transplant recipients) study is a multicenter double-blind randomized trial, including nondiabetic adult renal transplant recipients with serum 25-hydroxy vitamin D (25(OH) vitamin D) levels of <30 ng/mL, which is randomized 12 to 48 months after transplantation to receive high (100 000 IU) or low doses (12 000 IU) of cholecalciferol every 2 weeks for 2 months and then monthly for 22 months. The primary outcome was a composite endpoint, including diabetes mellitus, major cardiovascular events, cancer, and death. Of 536 inclusions (50.8 [13.7] years, 335 men), 269 and 267 inclusions were in the high-dose and low-dose groups, respectively. The serum 25(OH) vitamin D levels increased by 23 versus 6 ng/mL in the high-dose and low-dose groups, respectively (P < .0001). In the intent-to-treat analysis, 15% versus 16% of the patients in the high-dose and low-dose groups, respectively, experienced a first event of the composite endpoint (hazard ratio, 0.94 [0.60-1.48]; P = .78), whereas 1% and 4% of patients in the high-dose and low-dose groups, respectively, experienced an incident symptomatic fracture (odds ratio, 0.24 [0.07-0.86], P = .03). The incidence of adverse events was similar between the groups. After renal transplantation, high doses of cholecalciferol are safe but do not reduce extraskeletal complications (trial registration: ClinicalTrials.gov; identifier: NCT01431430).

Description of a transient proximal tubulopathy induced by amino acids perfusion in peptide receptor radionuclide therapy: A case report.

RATIONALE: Peptide receptor radionuclide therapy (PRRT) with radiolabeled somatostatin analogs is a targeted internal radiotherapy method used to treat tumors expressing somatostatin receptors. Concomitant amino acids perfusion is systematically performed in order to inhibit the proximal tubular uptake of the radionuclide and thus prevent nephrotoxicity. PATIENT CONCERNS:: a 67-year-old woman with an intestinal neuroendocrine tumor with multiple lymphadenopathies and liver metastases. The patient displayed a carcinoid syndrome with flushes including facial erythrosis and paresthesia. During the treatment, the patient exhibited emesis and severe cramps. DIAGNOSIS: We describe incomplete proximal tubulopathy induced by an amino acid therapy with [177Lu]-DOTA0-Tyr3-octreotate, which was reversible after treatment discontinuation. This diagnosis relies on metabolic acidosis, hypophosphatemia due to renal loss, tubular proteinuria and generalized aminoaciduria. Serum creatinine remained stable during and after the procedure. INTERVENTIONS: PRRT with radiolabeled somatostatin analog ([177Lu]-DOTA0-Tyr3-octreotate). In order to prevent PRRT induced nephrotoxicity, we used a solution of 20 amino acids including 22 g/L Lysine and 16.8 g/L Arginine. Metoclopramide was successfully used to control vomiting. During the treatment and at the time of cramps, the blood sample showed hypophosphatemia at 0.3 mmol/L justifying intravenous phosphate supplementation. The cramps disappeared after this infusion. OUTCOMES: Hypophosphatemia with low TmPO4/GFR was observed as well as an increase in ß2-microglobulinuria, urinary polyclonal light chains, and amino aciduria involving all amino acids. All these disturbances disappeared the day after the treatment and there was no acute kidney injury after 5 PRRT sessions. Six months after PRRT discontinuation, the patient had neither renal failure nor proximal tubulopathy. Aminoacid induced tubulopathy involves the main ligands of the megalin receptor. It has recently been demonstrated that cilastatin is a megalin inhibitor in the proximal tubule and therefore could represent an attractive alternative to amino acids for this purpose. LESSONS: This case report is a description of a nephroprotective strategy in which partial, and transient tubulopathy is induced, in order to decrease proximal absorption of a tubulotoxic molecule. This little known strategy could be used to prevent proximal tubular injury caused by others megalin-mediated nephrotoxicity medication.

Prevention of Cisplatin-Induced Acute Kidney Injury: A Systematic Review and Meta-Analysis.

PURPOSE: Cisplatin-induced acute kidney injury (CIA) is a serious adverse event that affects 20-40% of exposed patients, despite any implemented precaution to avoid it. The aim of this work was therefore to identify a relevant nephroprotective method for CIA. METHODS: We searched Pubmed, Embase, and Web of Science from 1 January 1978 to 1 June 2018, without language restriction. All studies (observational and interventional) assessing a CIA prevention method for adults receiving at least one course of cisplatin were eligible. The primary outcome was acute nephrotoxicity, as defined by the AKI-KDIGO classification (2012). The odds ratio and corresponding 95% confidence interval were used to assess the associations. We used narrative synthesis in case of heterogeneity regarding intervention, population, or outcome. When possible, a random-effects model was used to pool studies. The heterogeneity between studies was quantified (I2), and multiple meta-regressions were carried out to identify potential confounders. RESULTS: Within 4520 eligible studies, 51 articles fulfilling the selection criteria were included in the review, assessing 21 different prevention methods. A meta-analysis could only be performed on the 15 observational studies concerning magnesium supplementation (1841 patients), and showed a significant nephroprotective effect for all combined grades of CIA (OR 0.24, [0.19-0.32], I2 = 0.0%). This significant nephroprotective effect was also observed for grades 2 and 3 CIA (OR 0.22, [0.14-0.33], I2 = 0.0% and OR 0.25, [0.08-0.76], I2 = 0.0%, respectively). CONCLUSION: While no method of prevention had so far demonstrated its indisputable efficacy, our results highlight the potential protective effect of magnesium supplementation on cisplatin-induced acute nephrotoxicity. TRIAL REGISTRATION: This study is registered in PROSPERO, CRD42018090612.