Developing International Classification of Disease code definitions for the study of enteric infection sequelae in Canada.

Background: Enteric infections and their chronic sequelae are a major cause of disability and death. Despite the increasing use of administrative health data in measuring the burden of chronic diseases in the population, there is a lack of validated International Classification of Disease (ICD) code-based case definitions, particularly in the Canadian context. Our objective was to validate ICD code definitions for sequelae of enteric infections in Canada: acute kidney injury (AKI); hemolytic uremic syndrome (HUS); thrombotic thrombocytopenic purpura (TTP); Guillain-Barré syndrome/Miller-Fisher syndrome (GBS/MFS); chronic inflammatory demyelinating polyneuropathy (CIDP); ankylosing spondylitis (AS); reactive arthritis; anterior uveitis; Crohn's disease, ulcerative colitis, celiac disease, erythema nodosum (EN); neonatal listeriosis (NL); and Graves' disease (GD).

Hypertension in children with congenital anomalies of the kidney and urinary tract.

Background: Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of childhood chronic kidney disease (CKD). We hypothesized that hypertension varies across CAKUT categories and increases the risk of CKD.

Methods: This was a retrospective cohort study and included cases with a multicystic dysplastic kidney (MCDK, n = 81), unilateral kidney agenesis (UKA, n = 47), kidney hypoplasia (KH, n = 130), and posterior urethral valves (PUV, n = 75).

Risk factors associated with short- and long-term kidney injury in children with post infectious glomerulonephritis.

Background: Post infectious glomerulonephritis (PIGN) is the most common form of acute glomerulonephritis in children. The objective of this study was to evaluate the risk factors for kidney injury in children with PIGN referred to a tertiary care center.

Methods: This was a retrospective cohort study.

Predicting outcomes in children with congenital anomalies of the kidney and urinary tract.

Background: Congenital anomalies of the kidney and urinary tract (CAKUT) are the most frequent causes of childhood chronic kidney disease (CKD). Using a large CAKUT cohort, we sought to identify the predictors of CKD and to develop a prediction model that informs a risk-stratified clinical pathway.

Methods: This was a retrospective cohort study including cases with multicystic dysplastic kidneys (MCDK), unilateral kidney agenesis (UKA), kidney hypoplasia (KH), and posterior urethral valves (PUV).

Congenital anomalies of the kidney and urinary tract: defining risk factors of disease progression and determinants of outcomes.

Congenital anomalies of the kidney and urinary tract (CAKUT) result from disruptions in normal kidney and urinary tract development during fetal life and collectively represent the most common cause of kidney failure in children worldwide. The antenatal determinants of CAKUT are diverse and include mutations in genes responsible for normal nephrogenesis, alterations in maternal and fetal environments, and obstruction within the normal developing urinary tract. The resultant clinical phenotypes are complex and depend on the timing of the insult, the penetrance of underlying gene mutations, and the severity and timing of obstruction related to the sequence of normal kidney development.

Kidney length standardized to body length predicts outcome in infants with a solitary functioning kidney.

Background: Infants with a solitary functioning kidney (SFK) are at risk for chronic kidney injury (CKI). Lack of compensatory kidney growth (CKG) is associated with CKI, but measuring CKG is challenging since it is typically reported relative to normal kidneys. This study aims to (1) standardize SFK growth in infants, (2) investigate the relationship between standardized kidney length and clinical outcomes, and (3) use these results to develop a risk-based prediction model and local clinical pathway for SFK care.

Fluid overload and acute kidney injury in children with tumor lysis syndrome.

Aim: Tumor lysis syndrome (TLS) is a common oncologic emergency among patients with pediatric hematologic malignancies. The mainstay of TLS management is aggressive intravenous hydration. However, the epidemiology of fluid overload (FO) and acute kidney injury (AKI) in this population is understudied.

Outcomes of solitary functioning kidneys-renal agenesis is different than multicystic dysplastic kidney disease.

Background: Multicystic dysplastic kidney (MCDK) disease and unilateral renal agenesis (URA) are well-known causes of a solitary functioning kidney (SFK) and are associated with long-term kidney injury. The aims of this study were to characterize the natural history of SFK at our center, define the risk factors associated with chronic kidney injury, and identify distinguishing features between URA and MCDK that predict outcome.

Methods: This was a retrospective cohort study of 230 SFK patients.

Dietary intakes of children with nephrotic syndrome.

Background: Our multidisciplinary clinical pathway for treatment of childhood nephrotic syndrome (NS) was established with the goal of standardizing local clinical practice. This descriptive study aimed to assess nutrient intakes of children with newly diagnosed NS compared with nutrition goals defined by our pathway.

Methods: Our pathway includes evidence-based recommendations that target daily intakes during corticosteroid induction therapy: energy (Estimated Energy Requirements (EER) × Sedentary Physical Activity (PA)), sodium (1 mg/kcal), calcium (Dietary Reference Intake (DRI) + 500 mg elemental calcium), and vitamin D (DRI +800-1000 IU).

Henoch-Schönlein purpura in children: Use of corticosteroids for prevention and treatment of renal disease.

Question: A few patients have previously presented to my clinic with palpable purpura, joint inflammation, and severe abdominal pain characteristic of Henoch-Schönlein purpura (HSP). Considering that renal injury is the primary long-term complication of HSP, are corticosteroids effective in preventing or treating renal disease in children with HSP?

Answer: Henoch-Schönlein purpura is self-limiting in 94% of children, but permanent renal injury is reported in one-fifth of children with nephritic or nephrotic features. Corticosteroids have been considered as candidates for preventing and treating renal involvement in HSP.

Baclofen Toxicity in Children With Acute Kidney Injury: Case Reports and Review of the Literature.

Baclofen is a medication used for tone management in cerebral palsy. Although it acts mainly at the spinal cord level, it can cause central nervous system adverse reactions at higher doses. Baclofen is mainly eliminated by renal excretion and there have been reports on adverse events when used in adults with renal impairment; however, there are no consensus guidelines as to the dose adjustments required due to renal impairment.

Induction prednisone dosing for childhood nephrotic syndrome: how low should we go?

Background: Historically, children with nephrotic syndrome (NS) across British Columbia (BC), Canada have been cared for without formal standardization of induction prednisone dosing. We hypothesized that local historical practice variation in induction dosing was wide and that children treated with lower doses had worse relapsing outcomes.

Methods: This retrospective cohort study included 92 NS patients from BC Children's Hospital (1990-2010).

A Randomized Trial of a Multicomponent Intervention to Promote Medication Adherence: The Teen Adherence in Kidney Transplant Effectiveness of Intervention Trial (TAKE-IT).

Background: Poor adherence to immunosuppressive medications is a major cause of premature graft loss among children and young adults. Multicomponent interventions have shown promise but have not been fully evaluated.

Study Design: Unblinded parallel-arm randomized trial to assess the efficacy of a clinic-based adherence-promoting intervention.

Uromodulin deficiency alters tubular injury and interstitial inflammation but not fibrosis in experimental obstructive nephropathy.

Human GWAS and Mendelian genetic studies have linked polymorphic variants and mutations in the human uromodulin gene (UMOD) with chronic kidney disease. The primary function of this kidney-specific and secreted protein remains elusive. This study investigated whether UMOD deficiency modified responses to unilateral ureteral obstruction (UUO)-induced kidney injury.

Indications for kidney biopsy in idiopathic childhood nephrotic syndrome.

Background: Most cases of childhood nephrotic syndrome (NS) are due to minimal change disease (MCD), while a minority of children have focal segmental glomerulosclerosis (FSGS) and an unfavorable clinical course, requiring a kidney biopsy to confirm diagnosis. We hypothesized that clinical characteristics at diagnosis and initial response to corticosteroid treatment accurately predict FSGS and can be used to guide consistent practice in the indications for kidney biopsy.

Methods: This was a case control study (1990-2012).

Acute kidney injury in children with sickle cell disease-compounding a chronic problem.

In an article recently published in Pediatric Nephrology, Baddam and colleagues discuss the relatively underreported clinical problem of repeated episodes of acute kidney injury (AKI) in children with sickle cell disease (SCD). Their report is a cautionary note about the importance of repeated kidney injury on the background of underlying chronic kidney injury and its potential implications on long-term kidney outcome. In children and adults with SCD, this includes the effects of repeated vaso-occlusive crises and the management of these painful episodes with non-steroidal anti-inflammatory drugs.

Antenatal Determinants of Long-Term Kidney Outcome in Boys with Posterior Urethral Valves.

Background: Posterior urethral valves (PUV) are the most important cause of end-stage renal disease (ESRD) in young boys. The objective of this report was to define the antenatal determinants of long-term postnatal renal outcome in this condition.

Design: This was a retrospective cohort analysis.

The impact of small kidneys.

Background: Small kidneys due to renal hypodysplasia (RHD) result from a decrease in nephron number. The objectives of this study were to identify clinical variables that determine long-term renal outcome in children with RHD and to define the role of kidney size as a predictor of developing end-stage renal disease (ESRD).

Methods: This was a single-center retrospective cohort analysis.

Tacrolimus therapeutic drug monitoring and pediatric renal transplant graft outcomes.

Predose monitoring of tacrolimus levels is standard practice in the care of pediatric renal transplant patients. This is despite a paucity of data investigating the ideal target range in children, and controversy as to whether tacrolimus levels correlate with renal transplant outcomes. We performed a retrospective cohort analysis of 48 renal transplant patients at a single Canadian pediatric transplant center following the initiation of a tacrolimus-mycophenolate-prednisone-based IS protocol.

The importance of clinical pathways and protocols in pediatric nephrology.

Modern clinical practice is increasingly delivered by teams of individuals working within an environment of rising complexity and daunting patient care loads. Clinical pathways, protocols and checklists offer a way to assure coordination, efficiency, quality and safety in this chaotic environment. In this review, we discuss some of the principal characteristics of these clinical tools, some of the challenges involved with introducing them into clinical practice and the evidence that they can positively affect patient and system outcomes.

Urinary tract obstruction in the mouse: the kinetics of distal nephron injury.

Congenital urinary tract obstruction is the single most important cause of childhood chronic kidney disease. We have previously demonstrated that human and primate fetal obstruction impairs the development, differentiation, and maturation of the kidney. Research using postnatal rodent models has primarily focused upon the role of proximal tubular injury, with few reports of collecting duct system pathology or the suitability of the postnatal models for examining injury to the distal nephron.

Epidemiology of cardiac surgery-associated acute kidney injury in neonates: a retrospective study.

Background: Cardiac surgery is a known risk factor for acute kidney injury (AKI) in children. However, cardiac surgery-associated AKI (CS-AKI) in neonates has not been well studied. The objectives of this study were: (1) to describe the epidemiology of CS-AKI in neonates utilizing the Acute Kidney Injury Network (AKIN) definition, (2) to identify risk factors for neonatal CS-AKI, and (3) to determine if neonatal CS-AKI is associated with increased morbidity and mortality.

Congenital urinary tract obstruction: defining markers of developmental kidney injury.

Congenital urinary tract obstruction (diagnosed antenatally by ultrasound screening) is one of the main causes of end-stage kidney disease in children. The extent of kidney injury in early gestation and the resultant abnormality in kidney development determine fetal outcome and postnatal renal function. Unfortunately, the current approach to diagnostic evaluation of the severity of injury has inherently poor diagnostic and prognostic value because it is based on the assessment of fetal tubular function from fetal urine samples rather than on estimates of the dysplastic changes in the injured developing kidney.