Outcomes of Prophylactic Peritoneal Dialysis Catheter Insertion in Children Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVES: The objective of this Prospective Register of Systematic Reviews (CRD42022384192) registered systematic review and meta-analysis was to determine whether prophylactic peritoneal dialysis (PD) catheter insertion at the time of pediatric cardiac surgery is associated with improved short-term outcomes. DATA SOURCES: Databases search of the MEDLINE, EMBASE, CINAHL, and Cochrane Library completed in April 2021 and updated October 2023. STUDY SELECTION: Two reviewers independently completed study selection, data extraction, and bias assessment. Inclusion criteria were randomized controlled trials (RCTs) and observational studies of children (≤ 18 yr) undergoing cardiac surgery with cardiopulmonary bypass. We evaluated use of prophylactic PD catheter versus not. DATA EXTRACTION: The primary outcome was in-hospital mortality, as well as secondary short-term outcomes. Pooled random-effect meta-analysis odds ratio with 95% CI are reported. DATA SYNTHESIS: Seventeen studies met inclusion criteria, including four RCTs. The non-PD catheter group received supportive care that included diuretics and late placement of PD catheters in the ICU. Most study populations included children younger than 1 year and weight less than 10 kg. Cardiac surgery was most commonly used for arterial switch operation. In-hospital mortality was reported in 13 studies; pooled analysis showed no association between prophylactic PD catheter placement and in-hospital mortality. There were mixed results for ICU length of stay and time to negative fluid balance, with some studies showing shortened duration associated with use of prophylactic PD catheter insertion and others showing no difference. Overall, the studies had high risk for bias, mainly due to small sample size and lack of generalizability. CONCLUSIONS: In this meta-analysis, we have failed to demonstrate an association between prophylactic PD catheter insertion in children and infants undergoing cardiac surgery and reduced in-hospital mortality. Other relevant short-term outcomes, including markers of fluid overload, require further study.

Mutations in CLDN2 Are Not a Common Cause of Pediatric Idiopathic Hypercalciuria in Canada.

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.

Contexte: L'hypercalciurie est le facteur de risque le plus courant pour la formation de calculs rénaux, y compris chez les patients pédiatriques. Son étiologie est cependant souvent inconnue et les enfants sont fréquemment diagnostiqués avec une hypercalciurie idiopathique. Près de 50 % des enfants atteints d'hypercalciurie ont un parent de premier degré souffrant de calculs rénaux, ce qui suggère une importante contribution génétique à cette maladie. Une atteinte de la réabsorption du calcium au niveau du néphron proximal est impliquée dans la pathogenèse de l'hypercalciurie. La claudine-2, une protéine de jonction abondamment exprimée dans le tubule proximal, confère une perméabilité paracellulaire au calcium, laquelle est essentielle pour le transport à travers le tubule proximal, où la majorité du calcium filtré est réabsorbée. Objectif: Étudier la fréquence des variations dans le codage de CLDN2 dans une cohorte d'enfants atteints d'hypercalciurie idiopathique. Conception de l'étude: Une méthode mixte, comprenant un examen rétrospectif des dossiers médicaux et un entretien avec les patients, suivie d'un séquençage génétique. Cadre: Trois centres de soins tertiaires au Canada. Sujets: Des enfants (1 à 18 ans) atteints d'hypercalciurie idiopathique. Les patients dont l'hypercalciurie avait une autre cause ont été exclus. Méthodologie: Les données proviennent de 40 patients atteints d'hypercalciurie idiopathique. Le consentement éclairé à la collecte d'ADN a été obtenu pour treize patients. L'exon final et le seul exon codant pour CLDN2, a été séquencé. Résultats: La majorité des sujets étaient des garçons d'origine caucasienne et avaient des antécédents familiaux de calculs rénaux. Les taux d'hormone parathyroïdienne étaient significativement plus faibles que les valeurs de référence (p < 0,001). Les taux de 1,25 dihydroxyvitamine D étaient significativement plus élevés dans notre cohorte de patients, par rapport à l'intervalle de référence (p < 0,001). Le séquençage de CLDN2 n'a pas révélé de variations dans le codage. Limites: L'étude porte sur un faible échantillon de patients et le séquençage s'est limité à l'exon final du gène. Conclusion: Les mutations du gène CLDN2 ne sont pas une cause fréquente d'hypercalciurie idiopathique chez les enfants canadiens. D'autres études sont nécessaires pour préciser la ou les causes de l'hypercalciurie chez les patients pédiatriques et développer des traitements ciblés.

Association of Nonrecovery of Kidney Function After Pediatric Acute Kidney Injury With 5-Year Kidney and Nonkidney Outcomes.

Acute kidney injury is common in critically ill children, but the long-term outcomes are not well defined. OBJECTIVES: Evaluated whether nonrecovery of kidney function, following acute kidney injury, was associated with postdischarge mortality, healthcare utilization, and chronic kidney disease. DESIGN: Retrospective, two-center, observational study. SETTING: Two ICUs at tertiary children's hospitals in Montreal, QC. PARTICIPANTS: Pediatric patients (age ≤ 18 yr) with index admission to intensive care between January 1, 2003, and March 31, 2005. Children were excluded if they 1) died during admission, 2) did not have serum creatinine or urine output measured, 3) did not develop acute kidney injury, 4) could not be linked to administrative health data, and 5) (for chronic kidney disease outcome) had pre-existing renal disease by chart review, baseline estimated glomerular filtration rate measurement, or administrative health data codes. MAIN OUTCOMES AND MEASURES: Three-hundred seventy-eight patients' data were included for long-term mortality and healthcare utilization outcomes; 316 patients for long-term chronic kidney disease outcome. Outcomes were defined using provincial administrative healthcare data diagnosis, procedure, and billing codes. MAIN RESULTS: Nonrecovery of kidney function, defined as serum creatinine greater than or equal to 1.5× baseline at ICU discharge, occurred in 51 patients (13%). Nonrecovery of kidney function was not associated with long-term mortality (at 5-7 yr following hospital discharge), increased hospitalizations or emergency department visits (at 30-days, 1-year, and 5-yr follow-up), or increased physician visits (at 1- and 5-yr follow-up). Nonrecovery was associated with increased 30-day physician visits (adjusted relative risk, 1.40; 95% CI, 1.13-1.73) and chronic kidney disease diagnosis within 5 years of discharge (adjusted hazard ratio, 4.92, 95% CI, 1.77-13.70). CONCLUSIONS AND RELEVANCE: Nonrecovery of kidney function following an episode of acute kidney injury in critically ill children is associated with nearly five-fold increased risk for long-term chronic kidney disease. Acute kidney injury nonrecovery may be a useful marker to identify patients that are particularly important to follow-up post discharge for chronic kidney disease detection.

A Review on the Application and Limitations of Administrative Health Care Data for the Study of Acute Kidney Injury Epidemiology and Outcomes in Children.

Administrative health care databases contain valuable patient information generated by health care encounters. These "big data" repositories have been increasingly used in epidemiological health research internationally in recent years as they are easily accessible and cost-efficient and cover large populations for long periods. Despite these beneficial characteristics, it is also important to consider the limitations that administrative health research presents, such as issues related to data incompleteness and the limited sensitivity of the variables. These barriers potentially lead to unwanted biases and pose threats to the validity of the research being conducted. In this review, we discuss the effectiveness of health administrative data in understanding the epidemiology of and outcomes after acute kidney injury (AKI) among adults and children. In addition, we describe various validation studies of AKI diagnostic or procedural codes among adults and children. These studies reveal challenges of AKI research using administrative data and the lack of this type of research in children and other subpopulations. Additional pediatric-specific validation studies of administrative health data are needed to promote higher volume and increased validity of this type of research in pediatric AKI, to elucidate the large-scale epidemiology and patient and health systems impacts of AKI in children, and to devise and monitor programs to improve clinical outcomes and process of care.

Association Between Acute Kidney Injury Duration and Outcomes in Critically Ill Children.

OBJECTIVES: Acute kidney injury occurs frequently in children during critical illness and is associated with increased morbidity, mortality, and health resource utilization. We aimed to examine the association between acute kidney injury duration and these outcomes. DESIGN: Retrospective cohort study. SETTINGS: PICUs in Alberta, Canada. PATIENTS: All children admitted to PICUs in Alberta, Canada between January 1, 2015, and December 31, 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In total, 1,017 children were included, and 308 (30.3%) developed acute kidney injury during PICU stay. Acute kidney injury was categorized based on duration to transient (48 hr or less) or persistent (more than 48 hr). Transient acute kidney injury occurred in 240 children (77.9%), whereas 68 children (22.1%) had persistent acute kidney injury. Persistent acute kidney injury had a higher proportion of stage 2 and stage 3 acute kidney injury compared with transient acute kidney injury and was more likely to start within 24 hours from PICU admission. Persistent acute kidney injury occurred more frequently in those with higher illness severity and in those admitted with shock, sepsis, or with a history of transplant. Mortality varied significantly according to acute kidney injury status: 1.8% of children with no acute kidney injury, 5.4% with transient acute kidney injury, and 17.6% with persistent acute kidney injury died during hospital stay (p < 0.001). On multivariable analysis adjusting for illness and acute kidney injury severity, transient and persistent acute kidney injury were both associated with fewer ventilation-free days at 28 days (-1.28 d; 95% CI, -2.29 to -0.26 and -4.85 d; 95% CI, -6.82 to -2.88), vasoactive support-free days (-1.07 d; 95% CI, -2.00 to -0.15 and -4.24 d; 95% CI, -6.03 to -2.45), and hospital-free days (-1.93 d; 95% CI, -3.36 to -0.49 and -5.25 d; 95% CI, -8.03 to -2.47), respectively. CONCLUSIONS: In critically ill children, persistent and transient acute kidney injury have different clinical characteristics and association with outcomes. Acute kidney injury, even when its duration is short, carries significant association with worse outcomes. This risk increases further if acute kidney injury persists longer independent of the degree of its severity.

An Update on Hypertension in Children With Type 1 Diabetes.

The prevalence of hypertension in children with type 1 diabetes is reported to be between 6% and 16%. This potentially modifiable cardiovascular risk factor may go undiagnosed and undertreated, particularly in children with type 1 diabetes. Recent updated Canadian clinical practice guidelines recommend blood pressure screening every 2 years in children with type 1 diabetes as well as routine use of ambulatory blood pressure monitoring. Risk factors for hypertension in type 1 diabetes include poor glycemic control, overweight and obesity and genetic predisposition for hypertension. In terms of pathophysiology, sustained hyperglycemia, angiotensin I and II and inflammatory cytokines have been implicated. Endothelial and vascular dysfunction, with impaired endothelial-dependent vasodilation and increased carotid artery intima-media thickness, are evident in preclinical and clinical studies of children and not just in adults with type 1 diabetes. Early targeted therapy is critical to the control of hypertension and the development of related morbidity. As with hypertension in adults with type 1 diabetes, lifestyle modifications remain first-line therapy, including diet and glycemic control. Initial antihypertensive therapy should be an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker because of their associated effects of reducing microalbuminuria and improving renovascular outcomes. Pediatric hypertension in type 1 diabetes is an area of evolving study and opinion; identification and appropriate treatment is critical for the prevention of micro- and macrovascular complications in adulthood.