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UnlabelledIncident vertebral fractures and lumbar spine bone mineral density (BMD) were assessed in the 12 months following glucocorticoid initiation in 65 children with nephrotic syndrome. The incidence of vertebral fractures was low at 12 months (6 %) and most patients demonstrated recovery in BMD Z-scores by this time point.IntroductionVertebral fracture (VF) incidence following glucocorticoid (GC) initiation has not been previously reported in pediatric nephrotic syndrome.MethodsVF was assessed on radiographs (Genant method); lumbar spine bone mineral density (LS BMD) was evaluated by dual-energy X-ray absorptiometry.ResultsSixty-five children were followed to 12 months post-GC initiation (median age, 5.4 years; range, 2.3-17.9). Three of 54 children with radiographs (6 %; 95 % confidence interval (CI), 2-15 %) had incident VF at 1 year. The mean LS BMD Z-score was below the healthy average at baseline (mean ± standard deviation (SD), -0.5 ± 1.1; p = 0.001) and at 3 months (-0.6 ± 1.1; p < 0.001), but not at 6 months (-0.3 ± 1.3; p = 0.066) or 12 months (-0.3 ± 1.2; p = 0.066). Mixed effect modeling showed a significant increase in LS BMD Z-scores between 3 and 12 months (0.22 SD; 95 % CI, 0.08 to 0.36; p = 0.003). A subgroup (N = 16; 25 %) had LS BMD Z-scores that were ≤-1.0 at 12 months. In these children, each additional 1,000 mg/m(2) of GC received in the first 3 months was associated with a decrease in LS BMD Z-score by 0.39 at 12 months (95 % CI, -0.71 to -0.07; p = 0.017).ConclusionsThe incidence of VF at 1 year was low and LS BMD Z-scores improved by 12 months in the majority. Twenty-five percent of children had LS BMD Z-scores ≤-1.0 at 12 months. In these children, LS BMD Z-scores were inversely associated with early GC exposure, despite similar GC exposure compared to the rest of the cohort.

Background: Immunosuppression reduction for BK polyoma virus (BKV) must be balanced against risk of adverse alloimmune outcomes. We sought to characterize risk of alloimmune events after BKV within context of HLA-DR/DQ molecular mismatch (mMM) risk score., Methods: This single-center study evaluated 460 kidney transplant patients on tacrolimus-mycophenolate-prednisone from 2010-2021. BKV status was classified at 6-months post-transplant as "BKV" or "no BKV" in landmark analysis. Primary outcome was T-cell mediated rejection (TCMR). Secondary outcomes included all-cause graft failure (ACGF), death-censored graft failure (DCGF), de novo donor specific antibody (dnDSA), and antibody-mediated rejection (ABMR). Predictors of outcomes were assessed in Cox proportional hazards models including BKV status and alloimmune risk defined by recipient age and molecular mismatch (RAMM) groups., Results: At 6-months post-transplant, 72 patients had BKV and 388 had no BKV. TCMR occurred in 86 recipients, including 27.8% with BKV and 17% with no BKV (p = .05). TCMR risk was increased in recipients with BKV (HR 1.90, (95% CI 1.14, 3.17); p = .01) and high vs. low-risk RAMM group risk (HR 2.26 (95% CI 1.02, 4.98); p = .02) in multivariable analyses; but not HLA serological MM in sensitivity analysis. Recipients with BKV experienced increased dnDSA in univariable analysis, and there was no association with ABMR, DCGF, or ACGF., Conclusions: Recipients with BKV had increased risk of TCMR independent of induction immunosuppression and conventional alloimmune risk measures. Recipients with high-risk RAMM experienced increased TCMR risk. Future studies on optimizing immunosuppression for BKV should explore nuanced risk stratification and may consider novel measures of alloimmune risk., (© 2024 The Authors. Clinical Transplantation published by John Wiley & Sons Ltd.)

Background: Cisplatin is associated with acute kidney injury (AKI) and electrolyte abnormalities. Urine tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP-7) may be early cisplatin-AKI biomarkers., Methods: We conducted a 12-site prospective cohort study with pediatric patients treated with cisplatin (May 2013-December 2017). Blood and urine (measured for TIMP-2, IGFBP-7) were collected pre-cisplatin, 24-h post-cisplatin, and near hospital discharge during the first or second cisplatin cycle (early visit (EV)) and during second-to-last or last cisplatin cycle (late visit (LV))., Primary Outcome: serum creatinine (SCr)-defined AKI (≥ stage 1)., Results: At EV (median (interquartile (IQR)) age: 6 (2-12) years; 78 (50%) female), 46/156 (29%) developed AKI; at LV, 22/127 (17%) experienced AKI. At EV, TIMP-2, IGFBP-7, and TIMP-2*IGFBP-7 pre-cisplatin infusion concentrations were significantly higher in participants with vs. those without AKI. At EV and LV, biomarker concentrations were significantly lower in participants with vs. those without AKI at post-infusion and near-hospital discharge. Biomarker values normalized to urine creatinine were higher in patients with AKI compared to without (LV post-infusion, median (IQR): TIMP-2*IGFBP-7: 0.28 (0.08-0.56) vs. 0.04 (0.02-0.12) (ng/mg creatinine) 2 /1000; P < .001). At EV, pre-infusion biomarker concentrations had the highest area under the curves (AUC) (range: 0.61-0.62) for AKI diagnosis; at LV, biomarkers measured post-infusion and near discharge yielded the highest AUCs (range: 0.64-0.70)., Conclusions: TIMP-2*IGFBP-7 were poor to modest at detecting AKI post-cisplatin. Additional studies are needed to determine whether raw biomarker values or biomarker values normalized to urinary creatinine are more strongly associated with patient outcomes. A higher resolution version of the Graphical abstract is available as Supplementary information., (© 2023. The Author(s), under exclusive licence to International Pediatric Nephrology Association.)

De novo donor-specific antibody (dnDSA) after renal transplantation has been shown to correlate with antibody-mediated rejection and allograft loss. However, the lack of proven interventions and the time and cost associated with annual screening for dnDSA are difficult to justify for all recipients. We studied a well-characterized consecutive cohort (n = 949) with over 15 years of prospective dnDSA surveillance to identify risk factors that would help institute a resource-responsible surveillance strategy. Younger recipient age and HLA-DR/DQ molecular mismatch were independent predictors of dnDSA development. Combining both risk factors into recipient age molecular mismatch categories, we found that 52% of recipients could be categorized as low-risk for dnDSA development (median subclinical dnDSA-free survival at 5 and 10 years, 98% and 97%, respectively). After adjustment, multivariate correlates of dnDSA development included tacrolimus versus cyclosporin maintenance immunosuppression (hazard ratio [HR], 0.37; 95% CI, 0.2-0.6; P < .0001) and recipient age molecular mismatch category: intermediate versus low (HR, 2.48; 95% CI, 1.5-4.2; P = .0007), high versus intermediate (HR, 2.56; 95% CI, 1.6-4.2; P = .0002), and high versus low (HR, 6.36; 95% CI, 3.7-10.8; P < .00001). When combined, recipient age and HLA-DR/DQ molecular mismatch provide a novel data-driven approach to reduce testing by >50% while selecting those most likely to benefit from dnDSA surveillance., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Few studies describe acute kidney injury (AKI) burden during paediatric cisplatin therapy and post-cisplatin kidney outcomes. We determined risk factors for and rate of (1) AKI during cisplatin therapy, (2) chronic kidney disease (CKD) and hypertension 2-6 months post-cisplatin, and (3) whether AKI is associated with 2-6-month outcomes., Methods: This prospective cohort study enrolled children (aged < 18 years at cancer diagnosis) treated with cisplatin from twelve Canadian hospitals. AKI during cisplatin therapy (primary exposure) was defined based on Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria (≥ stage one). Severe electrolyte abnormalities (secondary exposure) included ≥ grade three hypophosphatemia, hypokalemia, or hypomagnesemia (National Cancer Institute Common Terminology Criteria for Adverse Events v4.0). CKD was albuminuria or decreased kidney function for age (KDIGO guidelines). Hypertension was defined based on the 2017 American Academy of Pediatrics guidelines., Results: Of 159 children (median [interquartile range [IQR]] age: 6 [2-12] years), 73/159 (46%) participants developed AKI and 55/159 (35%) experienced severe electrolyte abnormalities during cisplatin therapy. At median [IQR] 90 [76-110] days post-cisplatin, 53/119 (45%) had CKD and 18/128 (14%) developed hypertension. In multivariable analyses, AKI was not associated with 2-6-month CKD or hypertension. Severe electrolyte abnormalities during cisplatin were associated with having 2-6-month CKD or hypertension (adjusted odds ratio (AdjOR) [95% CI]: 2.65 [1.04-6.74]). Having both AKI and severe electrolyte abnormalities was associated with 2-6-month hypertension (AdjOR [95% CI]: 3.64 [1.05-12.62])., Conclusions: Severe electrolyte abnormalities were associated with kidney outcomes. Cisplatin dose optimization to reduce toxicity and clear post-cisplatin kidney follow-up guidelines are needed. A higher resolution version of the Graphical abstract is available as Supplementary information., (© 2022. The Author(s), under exclusive licence to International Pediatric Nephrology Association.)

When people make inferences about other people's minds, called theory of mind (ToM), a cortical network becomes active. The right temporoparietal junction (TPJ) is one of the most consistently responsive nodes in that network. Here we used a pictorial, reaction-time, ToM task to study brain activity in the TPJ and other cortical areas. Subjects were asked to take the perspective of a cartoon character and judge its knowledge of a visual display in front of it. The right TPJ showed evidence of encoding information about the implied visual knowledge of the cartoon head. When the subject was led to believe that the head could see a visual change take place, activity in the right TPJ significantly reflected that change. When the head could apparently not see the same visual change take place, activity in the right TPJ no longer significantly reflected that change. The subject could see the change in all cases; the critical factor that affected TPJ activity was whether the subject was led to think the cartoon character could see the change. We also found that whether the beliefs attributed to the cartoon head were true or false did not significantly affect activity in the present paradigm. These results suggest that the right TPJ may play a role in modeling the contents of the minds of others, perhaps more than it participates in evaluating the truth or falsity of that content., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Hypercalciuria is the most common risk factor for kidney stone formation, including in pediatric patients. However, the etiology is often unknown and children are frequently diagnosed with idiopathic hypercalciuria. Nearly 50% of children with hypercalciuria have a first-degree relative with kidney stones, suggesting a strong genetic basis for this disease. A failure of calcium reabsorption from the proximal nephron is implicated in the pathogenesis of hypercalciuria. Claudin-2 is a tight junction protein abundantly expressed in the proximal tubule. It confers paracellular permeability to calcium that is essential for transport across the proximal tubule where the majority of filtered calcium is reabsorbed., Objective: Our objective was to examine the frequency of coding variations in CLDN2 in a cohort of children with idiopathic hypercalciuria., Design: Mixed method including retrospective chart review and patient interview, followed by genetic sequencing., Setting: Three tertiary care centers in Canada., Patients: Children (age 1-18 years) with idiopathic hypercalciuria. Patients with other causes of hypercalciuria were excluded., Methods: Data were collected from 40 patients with idiopathic hypercalciuria. Informed consent to collect DNA was obtained from 13 patients, and the final and only coding exon of CLDN2 was sequenced., Results: The majority of patients were male, white, and had a positive family history of kidney stones. Parathyroid hormone levels were significantly lower than the reference range ( P < .001). The levels of 1,25-dihydroxyvitamin D were also significantly higher in our patient cohort, relative to the reference range ( P < .001). Sequence analysis of CLDN2 did not identify any coding variations., Limitations: Sequencing analysis was limited to the final coding exon and small sample size., Conclusions: CLDN2 coding variations are not a common cause of idiopathic hypercalciuria in Canadian children. Further study is needed to determine the causes of hypercalciuria in pediatric patients and develop targeted therapies., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: RTA work closely with Dr Hartwig as a member of the KRESCENT leadership team (she is a handling editor)., (© The Author(s) 2022.)

Background: Few studies have described associations between the AKI biomarkers urinary neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) with AKI in cisplatin-treated children. We aimed to describe excretion patterns of urine NGAL and KIM-1 and associations with AKI in children receiving cisplatin., Methods: Participants ( n =159) were enrolled between 2013 and 2017 in a prospective cohort study conducted in 12 Canadian pediatric hospitals. Participants were evaluated at early cisplatin infusions (at first or second cisplatin cycle) and late cisplatin infusions (last or second-to-last cycle). Urine NGAL and KIM-1 were measured ( 1 ) pre-cisplatin infusion, ( 2 ) post-infusion (morning after), and ( 3 ) at hospital discharge at early and late cisplatin infusions. Primary outcome: AKI defined by serum creatinine rise within 10 days post-cisplatin, on the basis of Kidney Disease Improving Global Outcomes guidelines criteria (stage 1 or higher)., Results: Of 159 children, 156 (median [interquartile range (IQR)] age: 5.8 [2.4-12.0] years; 78 [50%] female) had biomarker data available at early cisplatin infusions and 127 had data at late infusions. Forty six of the 156 (29%) and 22 of the 127 (17%) children developed AKI within 10 days of cisplatin administration after early and late infusions, respectively. Urine NGAL and KIM-1 concentrations were significantly higher in patients with versus without AKI (near hospital discharge of late cisplatin infusion, median [IQR] NGAL levels were 76.1 [10.0-232.7] versus 14.9 [5.4-29.7] ng/mg creatinine; KIM-1 levels were 4415 [2083-9077] versus 1049 [358-3326] pg/mg creatinine; P <0.01). These markers modestly discriminated for AKI (area under receiver operating characteristic curve [AUC-ROC] range: NGAL, 0.56-0.72; KIM-1, 0.48-0.75). Biomarker concentrations were higher and better discriminated for AKI at late cisplatin infusions (AUC-ROC range, 0.54-0.75) versus early infusions (AUC-ROC range, 0.48-0.65)., Conclusions: Urine NGAL and KIM-1 were modest at discriminating for cisplatin-associated AKI. Further research is needed to determine clinical utility and applicability of these markers and associations with late kidney outcomes., Competing Interests: T.D. Blydt-Hansen reports having ownership interest in Apple, Hydrogenics, and Royal Bank of Canada; receiving honoraria from Astellas Canada; receiving research funding from Astellas Canada, Canadian Institutes of Health Research, Child and Family Research Institute, Children’s Hospital of Manitoba Research Institute, and Transplant Research Foundation of BC; having consultancy agreements with Astellas Canada, Horizon Canada, Novartis, and Ricordati; and serving as a scientific advisor for or member of BC Transplant, Canadian National Transplant Research Program, International Pediatric Transplant Association (council member), and North American Pediatric Transplant and Collaborative Studies. B.C. Carleton reports serving as a scientific advisor for or member of AEVI Genomic Medicine, United Health Group Pharmacogenomics (on the advisory committee); having consultancy agreements with Dynacare Specialized Diagnostics; receiving research funding from Dynacare Specialized Diagnostics (ended in June 2021) and grants from federal and provincial agencies; and having other interests/relationships with Rare Disease Society. P. Devarajan reports having consultancy agreements with Alnylam, Dicerna, Natera, and Reata; being a coinventor on patents for the use of NGAL as a biomarker of kidney injury; and serving on speakers bureaus for BioPorto Inc., Natera, and Reata. M. Pinsk reports having consultancy agreements with Canadian Agency for Drugs and Technologies in Health (as consultant); serving as an expert witness for legal consultations (multiple); and having other interests/relationships with Canadian Society of Nephrology, International Pediatric Nephrology Association, and Medical Council of Canada. K. R. Schultz reports having consultancy agreements with AVM Biotech, Celgene/Juno, Jazz, and Medpace; receiving honoraria from Bristol Myers Squibb (BMS), Celegene, and Jazz; serving on the data safety monitoring boards for BMS/Juno and Medpace; and serving as a scientific advisor or membership of Jazz. R.T. Tsuyuki reports receiving research funding from AstraZeneca, Merck Canada Inc., and Sanofi; serving as the editor-in-chief for Canadian Pharmacists Journal, and as president, chair, and on the board of directors for Hypertension Canada; receiving honoraria from Emergent Biosolutions and Merck Canada Inc.; and having consultancy agreements with Emergent Biosolutions and Shoppers Drug Mart. M. Zappitelli reports having consultancy agreements with BioPorto Inc., CytoPheryx Inc., and Eloxx Pharmaceuticals; receiving honoraria from Bioporto Inc. and Eloxx Pharmaceuticals; and having other interests/relationships with Canadian Pediatric Nephrologists Association, Canadian Society of Nephrology, and Kidney Foundation of Canada. All remaining authors have nothing to disclose., (Copyright © 2022 by the American Society of Nephrology.)

Purpose of Program: Integrated knowledge translation (IKT) is a collaborative approach whereby knowledge created through health research is utilized in ways that are relevant to the needs of all stakeholders. However, research teams have limited capacity and know-how for achieving IKT, resulting in a disconnect between the generation and application of knowledge. The goal of this report is to describe how IKT research was achieved across a large-scale, patient-oriented research network, Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease (Can-SOLVE CKD)., Sources of Information: Resources to facilitate knowledge translation (KT) planning across the network were developed by the Can-SOLVE CKD Knowledge User/Knowledge Translation Committee with reference to established Canadian KT and patient engagement tools and frameworks, review of the published and gray literature, and expertise of committee members., Methods: The Can-SOLVE CKD Knowledge User/Knowledge Translation Committee consisting of patient partners, health care providers, policymakers, and researchers provided oversight of the development and implementation of the network's IKT initiatives. Guided by its strategic framework, the committee developed KT planning templates and review checklists to assist network projects with preparing for dissemination, implementation, and scale and spread of their interventions. The committee has acted in a consultative capacity to facilitate IKT across network initiatives and has supported capacity building through KT activities aimed at network membership and knowledge users more broadly., Key Findings: The Can-SOLVE CKD Knowledge User/Knowledge Translation Committee established a nation-wide strategy for KT infrastructure and capacity building. Acting as a knowledge intermediary, the committee has connected research teams with knowledge users across Canada to support practices and policies informed by evidence generated by the network. The committee has developed KT initiatives, including a Community of Practice, whereby participants across different regions and disciplines convene regularly to share health research knowledge and communications strategies relevant to the network. Critically, patients are engaged and contribute throughout the research process. Examples of IKT activities from select projects are provided, as well as ways for sustaining the network's KT platform., Limitations: The KT resources developed by the committee were adapted from other established resources to meet the needs of the network and have not undergone formal evaluation in this context. Given the broad scope of the network, resources to facilitate implementation and knowledge user engagement may not meet the needs of all initiatives and must be tailored accordingly. Knowledge barriers, including a lack of information and skills related to conceptual and practical aspects of KT, among network members provided a rationale for various KT capacity-building initiatives., Implications: The approach described here offers a practical method for achieving IKT, including how to plan, implement, and sustain initiatives across large-scale health research networks. Within the context of Can-SOLVE CKD, these efforts will shorten knowledge-practice gaps through producing and applying relevant research to improve the lives of people living with kidney disease., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2021.)

Purpose of Review: (1) To provide commentary on the 2017 update to the Kidney Disease Improving Global Outcomes (KDIGO) 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD); (2) to apply the evidence-based guideline update for implementation within the Canadian health care system; (3) to provide comment on the care of children with chronic kidney disease (CKD); and (4) to identify research priorities for Canadian patients., Sources of Information: The KDIGO 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of CKD-MBD., Methods: The commentary committee co-chairs selected potential members based on their knowledge of the Canadian kidney community, aiming for wide representation from relevant disciplines, academic and community centers, and different geographical regions., Key Findings: We agreed with many of the recommendations in the clinical practice guideline on the diagnosis, evaluation, prevention, and treatment of CKD-MBD. However, based on the uncommon occurrence of abnormalities in calcium and phosphate and the low likelihood of severe abnormalities in parathyroid hormone (PTH), we recommend against screening and monitoring levels of calcium, phosphate, PTH, and alkaline phosphatase in adults with CKD G3. We suggest and recommend monitoring these parameters in adults with CKD G4 and G5, respectively. In children, we agree that monitoring for CKD-MBD should begin in CKD G2, but we suggest measuring ionized calcium, rather than total calcium or calcium adjusted for albumin. With regard to vitamin D, we suggest against routine screening for vitamin D deficiency in adults with CKD G3-G5 and G1T-G5T and suggest following population health recommendations for adequate vitamin D intake. We recommend that the measurement and management of bone mineral density (BMD) be according to general population guidelines in CKD G3 and G3T, but we suggest against routine BMD testing in CKD G4-G5, CKD G4T-5T, and in children with CKD. Based on insufficient data, we also recommend against routine bone biopsy in clinical practice for adults with CKD or CKD-T, or in children with CKD, although we consider it an important research tool., Limitations: The committee relied on the evidence summaries produced by KDIGO. The CSN committee did not replicate or update the systematic reviews., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: R.M.H. has received investigator-initiated research funding from OPKO Health, Inc (OPKO Renal Division) and Sanofi. R.A.M. has received research funding from the Patient-Centered Outcomes Research Institute (PCORI), the American Society of Hematology (ASH), and the American College of Rheumatology (ACR). R.T.A. has received consulting honoraria from Ardelyx, Inc and from Advicenne. M.B. has received honoraria for advisory board membership with Otsuka Canada Pharmaceutical Inc (OCPI) and AstraZeneca. M.U.B. has received honoraria for consultation, advisory board membership, speaking engagements, or research funding from Janssen, OCPI, and Sanofi. G.K. declared no conflicts of interest. F.M.-W. has received honoraria for conferences, advisory board membership, or research funding from Amgen Inc, Otsuka Canada Pharmaceutical Inc, and Sanofi. M.R. declared no conflicts of interest. R.W. declared no conflicts of interest. P.D.A. declared no conflicts of interest. P.F. has no conflicts of interest. A.G. declared no conflicts of interest. K.K.J. has received honoraria for consultation or advisory board membership from Boehringer Ingelheim, Baxter, Amgen Inc, Sanofi, Eli Lilly and Company, LEO Pharma Inc Canada, and AstraZeneca. M.K. declared no conflicts of interest. B.A.K. declared no conflicts of interest. S.M. has received honoraria for consultation, advisory board membership, research funding, unrestricted grants, and educational grants from the Ontario Ministry of Health, NGX, Health Canada, Nutrigenomix Inc, Mitacs, Central East Local Health Integration Network, Ontario Renal Network (ORN), Sanofi, Shire, Amgen Inc, Sanofi Genzyme, Boehringer Ingelheim, and Baxter. K.M. declared no conflicts of interest. A.M. declared no conflicts of interest. M.P. declared no conflicts of interest. C.R. declared no conflicts of interest. S.D.S. has received honoraria for consultation, advisory board membership, and Canadian Medical Education (CME) lectures from the, Sanofi, Pfizer Inc, Janssen Inc, Amgen Inc, and Otsuka Canada Pharmaceutical Inc. A.J.V. has received honoraria for consultation from Paladin Labs Inc. D.Z. has received investigator-initiated research funding from Sanofi and has been a member of advisory boards for Otsuka Canada Pharmaceutical Inc, and Amgen Inc. C.M.C. has received honoraria for consultation, advisory board membership, or research funding from the Ontario Ministry of Health, Sanofi, Pfizer Inc, LEO Pharma Inc Canada, Astellas, Janssen Inc, Amgen Inc, Boehringer Ingelheim, and Baxter., (© The Author(s) 2020.)

Importance: Few multicenter pediatric studies have comprehensively described the epidemiologic characteristics of cisplatin-associated acute kidney injury using standardized definitions., Objective: To examine the rate of and risk factors associated with acute kidney injury among children receiving cisplatin infusions., Design, Setting, and Participants: This prospective cohort study examined children (aged <18 years) recruited from May 23, 2013, to March 31, 2017, at 12 Canadian pediatric academic health centers who were receiving 1 or more cisplatin infusion. Children whose estimated or measured glomerular filtration rate (GFR) was less than 30 mL/min/1.73 m2 or who had received a kidney transplant were excluded. Data analysis was performed from January 3, 2018, to September 20, 2019., Exposures: Cisplatin infusions., Main Outcomes and Measures: The primary outcome was acute kidney injury during cisplatin infusion, defined using a Kidney Disease: Improving Global Outcomes serum creatinine criteria-based definition (stage 1 or higher). The secondary outcome was acute kidney injury defined by electrolyte criteria from the National Cancer Institute Common Terminology Criteria for Adverse Events (grade 1 or higher). Assessments occurred at early (first or second cycle) and late (last or second to last cycle) cisplatin infusions., Results: A total of 159 children (mean [SD] age at early cisplatin infusion, 7.2 [5.3] years; 80 [50%] male) participated. The most common diagnoses were central nervous system tumors (58 [36%]), neuroblastoma (43 [27%]), and osteosarcoma (33 [21%]). Acute kidney injury (by serum creatinine level increase) occurred in 48 of 159 patients (30%) at early cisplatin infusions and 23 of 143 patients (16%) at late cisplatin infusions. Acute kidney injury (by electrolyte abnormalities) occurred in 106 of 159 patients (67%) at early cisplatin infusion and 100 of 143 patients (70%) at late cisplatin infusions. Neuroblastoma diagnosis and higher precisplatin GFR were independently associated with acute kidney injury (serum creatinine level increase) at early cisplatin infusions (adjusted odds ratio [aOR] for neuroblastoma vs other, 3.25; 95% CI, 1.18-8.95; aOR for GFR, 1.01; 95% CI, 1.00-1.03) and late cisplatin infusions (aOR for neuroblastoma vs other, 6.85; 95% CI, 1.23-38.0; aOR for GFR, 1.01; 95% CI, 1.00-1.03). Higher cisplatin infusion dose was also independently associated with acute kidney injury (serum creatinine level increase) at later cisplatin infusions (aOR, 1.05; 95% CI, 1.01-1.10)., Conclusions and Relevance: The findings suggest that acute kidney injury is common among children receiving cisplatin infusions and that rate and risk factors differ at earlier vs later infusions. These results may help with risk stratification with a goal of risk reduction.

Introduction: The University of Manitoba's ambulatory pediatric clerkship transitioned to daily encounter cards (DECs) from single in-training evaluation reports (ITERs). The impact of this change on quality of student assessment was unknown. Using the validated Completed Clinical Evaluation Report Rating (CCERR) scale, we compared the assessment quality of the single ITER to the DEC-based system., Methods: Block randomization was used to select from a cohort of ITER- and DEC-based assessments during equivalent points in clerkship training. Data were transcribed and anonymized and scored by two blinded raters using the CCERR., Results: Inter-rater reliability for total CCERR scores was substantive (> 0.6). Mean total CCERR score for the DEC cohort was significantly higher than for the ITER cohort (25.2 vs. 16.8, p  < 0.001), as were the mean scores for each item (2.81 vs. 1.86, p  < 0.05). Multivariate logistical regression supported the significant influence of assessment method on assessment quality., Conclusions: There is improvement in the average quality of student assessments associated with the transition from an ITER-based system to a DEC-based system. However, the improvement to only average CCERR scores for the DEC cohort suggests an unmet need for faculty development., (© International Association of Medical Science Educators 2019.)

Background: To assess reasons for continuing practice variation in the management of childhood nephrotic syndrome despite expert reviews and guidelines, we are conducting a longitudinal cohort study in children with glucocorticoid sensitive nephrotic syndrome. Objectives of this mid-study report are to describe patient and physician recruitment characteristics, glucocorticoid prescriptions, use of second line agents, biopsy practices, and adherence to study protocol., Methods: Children with new onset nephrotic syndrome and providers are being recruited from all 12 pediatric nephrology centres across Canada with > 2½ years follow-up. Data collection points of observation are over a minimum 36 months. Details of prescribed glucocorticoids and of all second line agents used during treatment are being collected. All relapses are being recorded with time to urinary remission of proteinuria., Results: To date, 243 patients (57.1% male) from 12 centres were included. Median number of patients per centre was 29 (range 2-45), and median age of cohort was 7.3 (IQR 4.2) at enrollment. Forty-eight physicians were recruited, median 5 (range 2-8) per site. Median number of relapses per patient year of follow-up was 2.1 (IQR 4). Cumulative dose variability of glucocorticoids prescribed per episode of proteinuria and length of treatment was observed between participating centres., Conclusion: The Canadian pediatric nephrology community established a longitudinal childhood nephrotic syndrome cohort study that confirms ongoing practice variability. The study will help to evaluate its impact on patient outcomes, and facilitate clinical trial implementation in nephrotic syndrome.

For youth with chronic kidney disease (CKD) and their families, shifting from pediatric to adult systems of renal care can be challenging. This study explored the transitional process experienced by youth with CKD and their families, including perceived facilitators and barriers to effective transition. Qualitative interviews were conducted with youth with CKD (n=28) and their parents (n=28). Ambiguity regarding healthcare provider roles within the adult system was frequently reported. Themes reflected parental challenge relinquishing care responsibility, synergistic and divergent expectations between youth and parents, tensions in youth self-care readiness, desired healthcare provider roles in transition preparedness, and system considerations in transition. A "learning stage" was recommended in which youth experienced the adult system while supported by known pediatric team members., Competing Interests: The authors reported no actual or potential conflict of interest in relation to this continuing nursing education activity., (Copyright© by the American Nephrology Nurses Association.)

Non-human primate neuroimaging is a rapidly growing area of research that promises to transform and scale translational and cross-species comparative neuroscience. Unfortunately, the technological and methodological advances of the past two decades have outpaced the accrual of data, which is particularly challenging given the relatively few centers that have the necessary facilities and capabilities. The PRIMatE Data Exchange (PRIME-DE) addresses this challenge by aggregating independently acquired non-human primate magnetic resonance imaging (MRI) datasets and openly sharing them via the International Neuroimaging Data-sharing Initiative (INDI). Here, we present the rationale, design, and procedures for the PRIME-DE consortium, as well as the initial release, consisting of 25 independent data collections aggregated across 22 sites (total = 217 non-human primates). We also outline the unique pitfalls and challenges that should be considered in the analysis of non-human primate MRI datasets, including providing automated quality assessment of the contributed datasets., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose of the Review: The Royal College of Physicians and Surgeons of Canada, with its Competence by Design initiative, is adopting the principles of competency-based medical education for residency training and continuing professional development. This initiative is being undertaken to meet the new standards of medical education in Canada, which include social accountability to meet performance-based outcomes of training. Nephrology is poised to implement Competence by Design into residency training in July 2018 and initiate a continuous quality improvement cycle to periodically renew and update the training requirements to be socially accountable and relevant in the modern age of medicine. The purpose of this review is to describe the process of entrustable professional activity and required training experience development and how they will affect subspecialty training in Canada., Sources of Information: The construct of competency-based medical education was derived from existing literature searches of the medical education literature, including documentation provided by the Royal College of Physicians and Surgeons of Canada. The content for each entrustable professional activity and milestone was derived by consensus from the community expertise of the working group, existing speciality training requirements, and elements of training requirements that the Royal College has been mandated to superimpose on all training requirements to meet societal expectations., Methods: The Royal College Specialty Committee in Nephrology participated in 2 years of preparation for this implementation, which has included the creation of a new educational design for the discipline and the elucidation of entrustable professional activities to describe the scope of nephrology practice and to guide teaching, learning, and assessment in residency, and ultimately maintenance of competence in practice., Key Findings: This article introduces the set of entrustable professional activities for adult and pediatric nephrology and describes the national consultation as part of an ongoing quality improvement of this work., Limitations: The implementation of Competence by Design will be tested by whether trainees embrace competency-based education by training to just entrustable professional activities, rather than the holistic model idealized in physician training. This is mitigated by the entrustable professional activity development incorporating multiple layers of competencies beyond a procedural skill. Time commitment for faculty will pose additional challenges in increasing the time for assessment of trainees, but is supported by electronic platforms at the Royal College to assist in data gathering and analysis., Implications: Competence by Design in nephrology is an outcomes-based curriculum and assessment platform that aims to train nephrologists to meet societal expectations in an ever-changing and complicated health care system. The goals are to increase safety and professional accountability to society and improve upon the already high standards of training within Canada., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Pediatric chronic kidney disease is psychologically, financially, and physically demanding on parents providing care. Parents often feel isolated because of the rarity of the condition, and geographic isolation often compounds this perception in Canada. Many parents seek assistance online for both information and social support., Objective: This study examines an online portal, titled "Ability Online," which was designed to provide support and information to a diverse group of parents using chat facilities, bulletin boards, and e-mail. Specifically, we sought to identify how the technologies offered in this system related to the support and information seeking needs for parents. Secondary aims of determining possible reasons for attrition over time were explored as well., Design: Mixed methodology sequential exploratory design using the qualitative methodology of descriptive interpretation., Setting: Telephone interviews., Patients: Twenty parents of pediatric patients with chronic kidney disease from four Canadian centers who engaged in an online social support system "Ability Online.", Measurements: Interview transcripts generated from 20 taped phone conversations were reviewed from parents who engaged in the online system, and the themes derived from these transcripts served to generate semistructured interview questions that focused on their use of, and perceived benefit from, this technology for social support. Follow-up telephone interviews were then conducted with a 6-person subset of the original group in an effort to further define the impact of technology on their experience. This same smaller cohort provided data on social supports, caregiver satisfaction, and caregiver stress., Results: Many parents experience a progression through which their needs for knowledge and support change over time. Specifically, parents describe a transition from pure information seeking, to seeking parental interaction, mutual support and collaboration, and ultimately to advocacy. Parents described how technology could be used to address those needs., Limitations: Our cohort was slightly more educated and representative of more urban populations than published data reflecting the population of North American pediatric patients living with kidney disease., Conclusions: Our data suggest themes of technology use influencing the goals of online support seeking. While our findings are preliminary, further study may inform Web designers to identify the changing needs of participants in designing such online support networks, and minimize the reasons that participants fail to adopt, or terminate their online experiences., Competing Interests: Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Treatment protocols for childhood nephrotic syndrome are highly variable between providers and care centres. We conducted a qualitative study to understand the complex multilevel processes that lead to practice variation and influence provider management of nephrotic syndrome., Methods: Focus groups with multidisciplinary pediatric nephrology care providers ( n = 67) from 10 Canadian pediatric nephrology centres that had more than 1 pediatric nephrologist were conducted between September 2013 and April 2015. Focus group discussions were guided by the Ottawa Model for Research Use. We used a semistructured interview guide to elicit participants' perspectives regarding 1) the work setting and context of the clinical environment, 2) reasons for variation at the provider level and 3) clinical practice guidelines for nephrotic syndrome. Focus group discussions were transcribed and analyzed concurrently with the use of qualitative content analysis., Results: Emerging themes were grouped into 2 categories: centre-level factors and provider-level factors. At the centre level, the type of care model used, clinic structures and resources, and lack of communication and collaboration within and between Canadian centres influenced care variation. At the provider level, use of experiential knowledge versus empirical knowledge and interpretation of patient characteristics influenced provider management of nephrotic syndrome., Interpretation: Centre- and provider-level factors play an important role in shaping practice differences in the management of childhood nephrotic syndrome. Further research is needed to determine whether variation in care is associated with disparities in outcomes., Competing Interests: Competing interests: None declared., (Copyright 2017, Joule Inc. or its licensors.)

The greatest risk factor for kidney stones is hypercalciuria, the etiology of which is largely unknown. A recent genome-wide association study (GWAS) linked hypercalciuria and kidney stones to a claudin-14 (CLDN14) risk haplotype. However, the underlying molecular mechanism was not delineated. Recently, renal CLDN14 expression was found to increase in response to increased plasma calcium, thereby inducing calciuria. We hypothesized therefore that some children with hypercalciuria and kidney stones harbor a CLDN14 variant that inappropriately increases gene expression. To test this hypothesis, we sequenced the CLDN14 risk haplotype in a cohort of children with idiopathic hypercalciuria and kidney stones. An intronic SNP was more frequent in affected children. Dual luciferase and cell-based assays demonstrated increased reporter or CLDN14 expression when this polymorphism was introduced. In silico studies predicted the SNP introduced a novel insulinoma-associated 1 (INSM1) transcription factor binding site. Consistent with this, repeating the dual luciferase assay in the presence of INSM1 further increased reporter expression. Our data suggest that children with the INSM1 binding site within the CLDN14 risk haplotype have a higher likelihood of hypercalciuria and kidney stones. Enhanced CLDN14 expression may play a role in the pathophysiology of their hypercalciuria., (© 2017 Wiley Periodicals, Inc.)

Background: Childhood cancer survivors experience adverse drug events leading to lifelong health issues. The Applying Biomarkers to Minimize Long-Term Effects of Childhood/Adolescent Cancer Treatment (ABLE) team was established to validate and apply biomarkers of cancer treatment effects, with a goal of identifying children at high risk of developing cancer treatment complications associated with thrombosis, graft-versus-host disease, hearing loss, and kidney damage. Cisplatin is a chemotherapy well known to cause acute and chronic nephrotoxicity. Data on biomarkers of acute kidney injury (AKI) and late renal outcomes in children treated with cisplatin are limited., Objective: To describe the design and methods of the pan-Canadian ABLE Nephrotoxicity study, which aims to evaluate urine biomarkers (neutrophil gelatinase-associated lipocalin [NGAL] and kidney injury molecule-1 [KIM-1]) for AKI diagnosis, and determine whether they predict risk of long-term renal outcomes (chronic kidney disease [CKD], hypertension)., Design: This is a 3-year observational prospective cohort study., Setting: The study includes 12 Canadian pediatric oncology centers., Patients: The target recruitment goal is 150 patients aged less than 18 years receiving cisplatin. Exclusion criteria : Patients with an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m 2 or a pre-existing renal transplantation at baseline., Measurements: Serum creatinine (SCr), urine NGAL, and KIM-1 are measured during cisplatin infusion episodes (pre-infusion, immediate post-infusion, discharge sampling). At follow-up visits, eGFR, microalbuminuria, and blood pressure are measured and outcomes are collected., Methods: Outcomes: AKI is defined as per SCr criteria of the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. CKD is defined as eGFR <90 mL/min/1.73m2 or albumin-to-creatinine ratio≥3mg/mmol. Hypertension is defined as per guidelines. Procedure: Patients are recruited before their first or second cisplatin cycle. Participants are evaluated during 2 cisplatin infusion episodes (AKI biomarker validation) and at 3, 12, and 36 months post-cisplatin treatment (late outcomes)., Limitations: The study has a relatively moderate sample size and short follow-up duration. There is potential for variability in data collection since multiple sites are involved., Conclusions: ABLE will provide a national platform to study biomarkers of late cancer treatment complications. The Nephrotoxicity study is a novel study of AKI biomarkers in children treated with cisplatin that will greatly inform on late cisplatin renal outcomes and follow-up needs., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Nephrotic syndrome is a commonly acquired kidney disease in children that causes significant morbidity due to recurrent episodes of heavy proteinuria. The management of childhood nephrotic syndrome is known to be highly variable among physicians and care centres., Objectives: The primary objective of the study is to determine centre-, physician-, and patient-level characteristics associated with steroid exposure and length of steroid treatment. We will also determine the association of dose and duration of steroid treatment and time to first relapse as a secondary aim. An embedded qualitative study utilizing focus groups with health care providers will enrich the quantitative results by providing an understanding of the attitudes, beliefs and local contextual factors driving variation in care., Design: Mixed-methods study; prospective observational cohort (quantitative component), with additional semi-structured focus groups of healthcare professionals (qualitative component)., Setting: National study, comprised of all 13 Canadian pediatric nephrology clinics., Patients: 400 patients under 18 years of age to be recruited over 2.5 years., Measurements: Steroid doses for all episodes (first presentation, first and subsequent relapses) tracked over course of the study. Physician and centre-level characteristics catalogued, with reasons for treatment preferences documented during focus groups., Methods: All patients tracked prospectively over the course of the study, with data comprising a prospective registry. One focus group at each site to enrich understanding of variation in care., Limitations: Contamination of treatment protocols between physicians may occur as a result of concurrent focus groups., Conclusions: Quantitative and qualitative results will be integrated at end of study and will collectively inform strategies for the development and implementation of standardized evidence-based protocols across centres.

The KDIGO (Kidney Disease: Improving Global Outcomes) clinical practice guideline for management of glomerulonephritis was recently released. The Canadian Society of Nephrology convened a working group to review the recommendations and comment on their relevancy and applicability to the Canadian context. A subgroup of adult nephrologists reviewed the guideline statements for management of glomerular disease in adults and agreed with most of the guideline statements developed by KDIGO. This commentary highlights areas for which there is lack of evidence and areas in need of translation of evidence into clinical practice. Areas of controversy or uncertainty, including the choice of second-line agents, are discussed in more detail. Existing practice variation also is addressed. The relevance of treatment recommendations to the Canadian practitioner is discussed., (Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

The KDIGO (Kidney Disease: Improving Global Outcomes) clinical practice guideline for management of glomerulonephritis was recently released. The Canadian Society of Nephrology convened a working group to review the recommendations and comment on their relevancy and applicability to the Canadian context. A subgroup of pediatric nephrologists reviewed the guideline statements for management of childhood nephrotic syndrome and agreed with most of the guideline statements developed by KDIGO. This commentary highlights areas in which there is lack of evidence and areas in need of translation of evidence into clinical practice. Areas of controversy or uncertainty, including the length of corticosteroid therapy for the initial presentation and relapses, definitions of steroid resistance, and choice of second-line agents, are discussed in more detail. Existing practice variation is also addressed., (Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: The contribution of copy-number variation (CNV) to disease has been highlighted with the widespread adoption of array-based comparative genomic hybridisation (aCGH) and microarray technology. Contiguous gene deletions involving ANKRD11 in 16q24.3 are associated with autism spectrum disorder (ASD) and intellectual disability (ID), while 16q24.1 deletions affecting FOXF1 are associated with congenital renal malformations, alveolar capillary dysplasia, and various other abnormalities. The disease associations of deletions in the intervening region, 16q24.2, have only been defined to a limited extent., Aim: To determine whether deletions affecting 16q24.2 are correlated with congenital anomalies., Methods: 35 individuals, each having a deletion in 16q24.2, were characterised clinically and by aCGH and/or SNP-genotyping microarray., Results: Several of the 35 16q24.2 deletions identified here closely abut or overlap the coding regions of FOXF1 and ANKRD11, two genes that have been previously associated with the disease. 25 patients were reported to have ASD/ID, and three were found to have bilateral hydronephrosis. 14 of the deletions associated with ASD/ID overlap the coding regions of FBXO31 and MAP1LC3B. These same genes and two others, C16orf95 and ZCCHC14, are also included in the area of minimal overlap of the three deletions associated with hydronephrosis., Conclusions: Our data highlight 16q24.2 as a region of interest for ASD, ID and congenital renal malformations. These conditions are associated, albeit without complete penetrance, with deletions affecting C16orf95, ZCCHC14, MAP1LC3B and FBXO31. The function of each gene in development and disease warrants further investigation.

We describe the experience of the focal segmental glomerulosclerosis clinical trial (FSGS CT) in the identification and recruitment of participants into the study. This National Institutes of Health funded study, a multicenter, open-label, randomized comparison of cyclosporine versus oral dexamethasone pulses plus mycophenolate mofetil, experienced difficulty and delays meeting enrollment goals. These problems occurred despite the support of patient advocacy groups and aggressive recruitment strategies. Multiple barriers were identified including: (1) inaccurate estimates of the number of potential incident FSGS patients at participating centers; (2) delays in securing one of the test agents; (3) prolonged time between IRB approval and execution of a subcontract (mean 7.5 ± 0.8 months); (4) prolonged time between IRB approval and enrollment of the first patient at participating sites (mean 19.6 ± 1.4 months); and (5) reorganization of clinical coordinating core infrastructure to align resources with enrollment. A Web-based anonymous survey of site investigators revealed site-related barriers to patient recruitment. The value of a variety of recruitment tools was of marginal utility in facilitating patient enrollment. We conclude that improvements in the logistics of study approval and regulatory start-up and testing of promising novel agents are important factors in promoting enrollment into randomized clinical trials in nephrology., (© 2013 Wiley Periodicals, Inc.)

Although case reports of hyperphosphatemia have been previously described in patients receiving liposomal amphotericin B, this has not been reported in patients receiving the lipid complex formulation. We report a case of hyperphosphatemia that persisted despite switching from liposomal to lipid complex amphotericin B in a child with invasive zygomycosis. This case suggests that in the context of acute renal dysfunction, hyperphosphatemia may also be observed with lipid complex amphotericin B. This case highlights the importance of differentiating between pseudohyperphosphatemia and hyperphosphatemia to prevent complications.

Hypertension affects one billion people and is a principal reversible risk factor for cardiovascular disease. Pseudohypoaldosteronism type II (PHAII), a rare Mendelian syndrome featuring hypertension, hyperkalaemia and metabolic acidosis, has revealed previously unrecognized physiology orchestrating the balance between renal salt reabsorption and K(+) and H(+) excretion. Here we used exome sequencing to identify mutations in kelch-like 3 (KLHL3) or cullin 3 (CUL3) in PHAII patients from 41 unrelated families. KLHL3 mutations are either recessive or dominant, whereas CUL3 mutations are dominant and predominantly de novo. CUL3 and BTB-domain-containing kelch proteins such as KLHL3 are components of cullin-RING E3 ligase complexes that ubiquitinate substrates bound to kelch propeller domains. Dominant KLHL3 mutations are clustered in short segments within the kelch propeller and BTB domains implicated in substrate and cullin binding, respectively. Diverse CUL3 mutations all result in skipping of exon 9, producing an in-frame deletion. Because dominant KLHL3 and CUL3 mutations both phenocopy recessive loss-of-function KLHL3 mutations, they may abrogate ubiquitination of KLHL3 substrates. Disease features are reversed by thiazide diuretics, which inhibit the Na-Cl cotransporter in the distal nephron of the kidney; KLHL3 and CUL3 are expressed in this location, suggesting a mechanistic link between KLHL3 and CUL3 mutations, increased Na-Cl reabsorption, and disease pathogenesis. These findings demonstrate the utility of exome sequencing in disease gene identification despite the combined complexities of locus heterogeneity, mixed models of transmission and frequent de novo mutation, and establish a fundamental role for KLHL3 and CUL3 in blood pressure, K(+) and pH homeostasis.

Objectives. Ondansetron is a 5-hydroxytryptamine (5-HT(3), serotonin) receptor antagonist used as antiemetic prophylaxis preceding chemotherapy administration. Hypokalemia is a rare complication of ondansetron, which may be underreported due to confounding emesis and chemotherapy-induced tubulopathy. We performed a prospective cohort study to determine if ondansetron caused significant hypokalemia independently as a result of renal potassium wasting. Methods. Twelve patients were recruited, with ten completing the study. Blood and urine samples were collected before and after ondansetron administration in patients admitted for intravenous (IV) hydration and chemotherapy. Dietary histories and IV records were analyzed to calculate sodium and potassium balances. Results. We observed an expected drop in urine osmolality, an increase in urine sodium, but no statistically significant change in sodium or potassium balance before and after ondansetron. Conclusion. Ondansetron does not cause significant potassium wasting in appropriately hydrated and nutritionally replete patients. Careful monitoring of serum potassium is recommended in patients with chronic nutritional or volume status deficiencies receiving this medication.

Background: The lack of adequate randomized clinical trials (RCT) has hindered identification of new therapies that are safe and effective for patients with primary focal segmental glomerulosclerosis (FSGS), especially in patients who fail to respond to corticosteroids and immunosuppressive therapies. Recent basic science advances have led to development of alternative treatments that specifically target aberrant pathways of fibrosis which are relevant to disease progression in FSGS. There is a need for a flexible Phase II study design which will test such novel antifibrotic strategies in order to identify agents suitable for phase III testing., Methods/design: The Novel Therapies for Resistant Focal Segmental Glomerulosclerosis (FONT) project is a multicenter Phase I/II RCT designed to investigate the potential efficacy of novel therapies for resistant FSGS. Adalimumab and galactose will be evaluated against conservative therapy consisting of the combination of lisinopril, losartan and atorvastatin. The sample size is defined to assure that if one of the treatments has a superior response rate compared to that of the other treatments, it will be selected with high probability for further evaluation. Comparison of primary and secondary endpoints in each study arm will enable a choice to be made of which treatments are worthy of further study in future Phase III RCT., Discussion: This report highlights the key features of the FONT II RCT including the two-step outcome analysis that will expedite achievement of the study objectives. The proposed phase II study design will help to identify promising agents for further testing while excluding ineffective agents. This staged approach can help to prevent large expenditures on unworthy therapeutic agents in the management of serious but rare kidney diseases.

Obesity is associated with an increased concentration of inflammatory mediators, which in turn, in adults, reduces the response to calcium channel blockers (CCBs). We reviewed the medical charts of 263 pediatric nephrology patients with renal conditions, with the aim of studying the effect of obesity on the response to L-type CCBs, angiotensin interrupting agents (ANGIs), or a combination of the two. Forty-eight patients were ultimately enrolled in the study: 25 obese and 23 non-obese patients. The effect of the treatments on lowering the blood pressure was compared in obese versus non-obese patients. The systolic response to CCBs, measured as at least a 10% reduction from the baseline, was significantly lower in the obese (12.5%) patients than in the non-obese (52.9%) ones. The differences in diastolic response (58.8 and 25% for non-obese and obese patients, respectively) did not reach significance. The percentage response to CCBs, however, was significantly less in the obese patients than in the non-obese patients for both systolic and diastolic blood pressure. Corticosteroids also significantly influenced the response to CCBs in terms of diastolic pressure (62.9 and 25% for non-obese and obese patients, respectively). None of the tested covariates, including obesity, was found to significantly influence the response to ANGIs alone or in various combinations with CCBs. In conclusion, obesity and corticosteroid therapy should be considered when initiating antihypertensive drug treatment in children with kidney disease as both may contribute to a reduced efficacy of the antihypertensive therapy.

Ondansetron is a commonly used medication in the treatment of nausea and vomiting arising from many etiologies, including chemotherapy. Although it is a highly safe drug, ondansetron use has been associated, rarely, with hypokalemia. However, it is unknown whether hypokalemia is due to the medication itself or to an underlying potassium disturbance caused by prior metabolic derangements, including vomiting. We relate a patient who presents with hypokalemia of unknown etiology, with evidence suggesting a possible relationship to ondansetron. We also present a proposed mechanism for this phenomenon.

Glycogen storage disease 1b (GSD 1b) is caused by a deficiency of glucose-6-phosphate translocase and the intracellular accumulation of glycogen. The disease presents with failure to thrive, hepatomegaly, hypoglycemia, lactic acidosis, as well as neutropenia causing increased susceptibility to pyogenic infections. We present a case of a young woman with GSD 1b who developed acute myelogenous leukemia while on long-term granulocyte colony-stimulating factor therapy. The presence of two rare diseases in a single patient raises suspicion that GSD 1b and acute myelogenous leukemia are linked. Surveillance for acute myelogenous leukemia should become part of the long-term follow-up for GSD 1b.

Neurophysiological studies in monkeys show that when multiple visual stimuli appear simultaneously in the visual field, they are not processed independently, but rather interact in a mutually suppressive way. This suggests that multiple stimuli compete for neural representation. Consistent with this notion, we have previously found in humans that functional magnetic resonance imaging (fMRI) signals in V1 and ventral extrastriate areas V2, V4, and TEO are smaller for simultaneously presented (i.e., competing) stimuli than for the same stimuli presented sequentially (i.e., not competing). Here we report that suppressive interactions between stimuli are also present in dorsal extrastriate areas V3A and MT, and we compare these interactions to those in areas V1 through TEO. To exclude the possibility that the differences in responses to simultaneously and sequentially presented stimuli were due to differences in the number of transient onsets, we tested for suppressive interactions in area V4, in an experiment that held constant the number of transient onsets. We found that the fMRI response to a stimulus in the upper visual field was suppressed by the presence of nearby stimuli in the lower visual field. Further, we excluded the possibility that the greater fMRI responses to sequential compared with simultaneous presentations were due to exogeneous attentional cueing by having our subjects count T's or L's at fixation, an attentionally demanding task. Behavioral testing demonstrated that neither condition interfered with performance of the T/L task. Our previous findings suggested that suppressive interactions among nearby stimuli in areas V1 through TEO were scaled to the receptive field (RF) sizes of neurons in those areas. Here we tested this idea by parametrically varying the spatial separation among stimuli in the display. Display sizes ranged from 2 x 2 degrees to 7 x 7 degrees and were centered at 5.5 degrees eccentricity. Based on the effects of display size on the magnitude of suppressive interactions, we estimated that RF sizes at an eccentricity of 5.5 degrees were <2 degrees in V1, 2-4 degrees in V2, 4-6 degrees in V4, larger than 7 degrees (but still confined to a quadrant) in TEO, and larger than 6 degrees (confined to a quadrant) in V3A. These estimates of RF sizes in human visual cortex are strikingly similar to those measured in physiological mapping studies in the homologous visual areas in monkeys.

The link between automatic and effortful processing and nonanalytic and analytic category learning was evaluated in a sample of 29 college undergraduates using declarative memory, semantic category search, and pseudoword categorization tasks. Automatic and effortful processing measures were hypothesized to be associated with nonanalytic and analytic categorization, respectively. Results suggested that contrary to prediction strong criterion-attribute (analytic) responding on the pseudoword categorization task was associated with strong automatic, implicit memory encoding of frequency-of-occurrence information. Data are discussed in terms of the possibility that criterion-attribute category knowledge, once established, may be expressed with few attentional resources. The data indicate that attention resource requirements, even for the same stimuli and task, vary depending on the category rule system utilized. Also, the automaticity emerging from familiarity with analytic category exemplars is very different from the automaticity arising from extensive practice on a semantic category search task. The data do not support any simple mapping of analytic and nonanalytic forms of category learning onto the automatic and effortful processing dichotomy and challenge simple models of brain asymmetries for such procedures., (Copyright 2001 Academic Press.)

The functional neuroanatomy of time estimation has not been well-documented. This research investigated the fMRI measured brain response to an explicit, prospective time interval production (TIP) task. The study tested for the presence of brain activity reflecting a primary time keeper function, distinct from the brain systems involved either in conscious strategies to monitor time or attentional resource and other cognitive processes to accomplish the task. In the TIP task participants were given a time interval and asked to indicate when it elapsed. Two control tasks (counting forwards, backwards) were administered, in addition to a dual task format of the TIP task. Whole brain images were collected at 1.5 Tesla. Analyses (n = 6) yielded a statistical parametric map (SPM ¿z¿) reflecting time keeping and not strategy (counting, number manipulation) or attention resource utilization. Additional SPM ¿z¿s involving activation associated with the accuracy and magnitude the of time estimation response are presented. Results revealed lateral cerebellar and inferior temporal lobe activation were associated with primary time keeping. Behavioral data provided evidence that the procedures for the explicit time judgements did not occur automatically and utilized controlled processes. Activation sites associated with accuracy, magnitude, and the dual task provided indications of the other structures involved in time estimation that implemented task components related to controlled processing. The data are consistent with prior proposals that the cerebellum is a repository of codes for time processing, but also implicate temporal lobe structures for this type of time estimation task., (Copyright 2000 Academic Press.)

When subjects direct attention to a particular location in a visual scene, responses in the visual cortex to stimuli presented at that location are enhanced, and the suppressive influences of nearby distractors are reduced. What is the top-down signal that modulates the response to an attended versus an unattended stimulus? Here, we demonstrate increased activity related to attention in the absence of visual stimulation in extrastriate cortex when subjects covertly directed attention to a peripheral location expecting the onset of visual stimuli. Frontal and parietal areas showed a stronger signal increase during this expectation than did visual areas. The increased activity in visual cortex in the absence of visual stimulation may reflect a top-down bias of neural signals in favor of the attended location, which derives from a fronto-parietal network.

The efficacy of angiotensin converting enzyme inhibitors in the treatment of heart disease is due in part to the accumulation of bradykinin (BK). Since BK can exert its effect by influencing cell proliferation, we chose to study the effect of BK on the growth of A10 vascular smooth muscle cells. Ligand binding studies to determine which BK receptor subtypes are present on A10 cells showed that both B1 and B2 receptors were present in approximately equal numbers. Examination of RNA synthesis demonstrated that BK inhibits uridine incorporation in a dose-dependent manner. This decrease in RNA synthesis was blocked by both B1 and B2 receptor antagonists, as well as by addition of indomethacin, a cyclooxygenase inhibitor. The latter result suggested that prostaglandins mediate the biological actions of BK. Consequently, we examined the direct effect of two prostaglandins, PGE2 and PGI2 (prostacyclin), on A10 cells. PGE2 caused a decrease in RNA synthesis, thus mimicking the effect of BK, while PGI2 did not. Therefore, the inhibition of RNA synthesis in A10 vascular smooth muscle cells by BK requires both B1 and B2 receptor subtypes and this action of BK is apparently mediated by de novo synthesis of prostaglandins.