Noninvasive testing for mycophenolate exposure in children with renal transplant using urinary metabolomics.

BACKGROUND: Despite the common use of mycophenolate in pediatric renal transplantation, lack of effective therapeuic drug monitoring increases uncertainty over optimal drug exposure and risk for adverse reactions. This study aims to develop a novel urine test to estimate MPA exposure based using metabolomics. METHODS: Urine samples obtained on the same day of MPA pharmacokinetic testing from two prospective cohorts of pediatric kidney transplant recipients were assayed for 133 unique metabolites by mass spectrometry. Partial least squares (PLS) discriminate analysis was used to develop a top 10 urinary metabolite classifier that estimates MPA exposure. An independent cohort was used to test pharmacodynamic validity for allograft inflammation (urinary CXCL10 levels) and eGFR ratio (12mo/1mo eGFR) at 1 year. RESULTS: Fifty-two urine samples from separate children (36.5% female, 12.0 ± 5.3 years at transplant) were evaluated at 1.6 ± 2.5 years post-transplant. Using all detected metabolites (n = 90), the classifier exhibited strong association with MPA AUC by principal component regression (r = 0.56, p < .001) and PLS (r = 0.75, p < .001). A practical classifier (top 10 metabolites; r = 0.64, p < .001) retained similar accuracy after cross-validation (LOOCV; r = 0.52, p < .001). When applied to an independent cohort (n = 97 patients, 1053 samples), estimated mean MPA exposure over Year 1 was inversely associated with mean urinary CXCL10:Cr (r = -0.28, 95% CI -0.45, -0.08) and exhibited a trend for association with eGFR ratio (r = 0.35, p = .07), over the same time period. CONCLUSIONS: This urinary metabolite classifier can estimate MPA exposure and correlates with allograft inflammation. Future studies with larger samples are required to validate and evaluate its clinical application.

Comparison of Socioeconomic Disparities in Pump Uptake Among Children With Type 1 Diabetes in 2 Canadian Provinces With Different Payment Models.

Importance: Insulin pumps improve glycemic control and quality of life in children with type 1 diabetes (T1D). Canada's provinces have implemented universal pediatric programs to improve access. However, these programs provide differing financial coverage, allowing for unique cross-jurisdictional comparisons. Objective: To evaluate possible socioeconomic status (SES) disparities in pump uptake in Québec, where pumps are fully funded, with those in Manitoba, where pumps are partially funded. Design, Setting, and Participants: Using health administrative databases and a clinical registry, parallel, population-based cohort studies of children with diabetes were conducted from April 1, 2011, in Québec, and April 1, 2012, in Manitoba, until March 31, 2017. In analysis conducted from July 1, 2019, to November 30, 2021, multivariable Cox proportional hazards regression models were applied to study the association between pump uptake and SES, defined using validated area-based material and social deprivation indices. Children aged 1 to 17 years with T1D were identified using a validated definition in administrative data (Québec) and a clinical registry (Manitoba). Those using pumps before the initiation of provincial programs were excluded. Exposures: Socioeconomic status. Main Outcomes and Measures: Insulin pump uptake. Results: A total of 2919 children with T1D were identified in Québec: 1550 male (53.1%), mean (SD) age at diagnosis, 8.3 (4.4) years, and 1067 (36.6%) were using a pump. In Manitoba, 636 children were identified: 364 male (57.2%), mean (SD) age at diagnosis, 8.8 (4.4) years, and 106 (16.7%) were using a pump. In Québec, the mean age at diagnosis of T1D was lower in children using the pump compared with those not using a pump (7.6 [4.1] vs 8.7 [4.5] years); sex distribution was similar (562 [52.7%] vs 988 [53.3%] male). No differences in mean (SD) age at diagnosis (8.8 [4.4] vs 8.8 [4.3] years) or sex (57 [53.8%] vs 307 [57.9%] male) were noted in both groups in Manitoba. Increasing material deprivation was associated with decreased pump uptake in both Québec (adjusted hazard ratio [aHR] 0.89; 95% CI, 0.85-0.93) and Manitoba (aHR, 0.70; 95% CI, 0.60-0.82). Inclusion of ethnic concentration did not change this association. Socioeconomic disparities in pump uptake were greater in Manitoba than Québec (P = .006 by t test; Cochran Q, 8.15; P = .004; I2 = 87.7%; 95% CI, 52.5%-96.8%). Conclusions and Relevance: The results of this study suggest that the program of full coverage for pumps available in Québec partially mitigates observed SES disparities in uptake and may be a model to improve access for all children with T1D.

Transition of Youth With Type 2 Diabetes: Predictors of Health-Care Utilization After Transition to Adult Care From Population-Based Administrative Data.

OBJECTIVES: In this study, we aimed to compare health-care visits pre- and posttransition from pediatric to adult care between youth with type 2 and type 1 diabetes. METHODS: We linked a clinical database with the Manitoba Population Research Data Repository to compare health-care visits 2 years before and after transition, and investigated baseline factors influencing health-care engagement. RESULTS: Youth with type 2 diabetes (n=196) vs type 1 diabetes (n=456) were more likely to be female (61% vs 44%), older at diagnosis (13.6 vs 10.6 years), live in northern regions and to be in the lowest socioeconomic status quartile (53% vs 5.4%). Seventy-six percent of youth with type 2 diabetes attended a follow-up visit within 2 years of transition compared to 97% of youth with type 1 diabetes. Youth with type 2 diabetes had higher rates of hospitalization pretransition (19.6 vs 11.6 admissions/100 patient years) and posttransition (24.7 vs 11.7 admissions/100 patient years) and fewer medical visits (pretransition: 2.4 vs 3.0 visits/person year [p<0.01]; posttransition: 1.6 vs 2.1 visits/person year [p<0.01]). Accounting for sex, geography, age, education, socioeconomic status and diabetes type, achieving 4 visits in 2 years posttransition was predicted by the number of visits pretransition (odds ratio, 1.35; 95% confidence interval, 1.23 to 1.49) and diabetes type (type 2 diabetes: odds ratio, 0.57; 95% confidence interval, 0.34 to 0.98). CONCLUSIONS: Youth with type 2 diabetes attend fewer medical follow-up visits pre- and posttransition to adult care compared to youth with type 1 diabetes. Focused, informed, specific transition planning is needed that addresses the unique characteristics of this population.

Assessing childhood health outcome inequalities with area-based socioeconomic measures: a retrospective cross-sectional study using Manitoba population data.

BACKGROUND: Socioeconomic gradients in health exist in Canada. Although multiple Canadian area-based socioeconomic measures (ABSM) have been developed, none have been specifically validated against pediatric outcomes. Our objective was to compare the strength of association between key pediatric health outcomes and a number of ABSM, including income quintile. METHODS: This was a retrospective cross-sectional assessment of the association between socioeconomic status (SES) measured by ABSM and 20 specific pediatric health outcomes. Data from the Manitoba Population Research Data Repository were used for residents aged 0-19 years from 2010 to 2015. Outcomes included birth-related events (e.g. mortality), vaccination uptake, hospitalizations, and teen pregnancy. Regression goodness of fit was used to assess the strength of individual associations. Inequality was measured by slope index of inequality (SII) and relative index of inequality (RII). RESULTS: Overall, 19 of 20 outcomes had socioeconomic gradients identified by SII and RII. The multidimensional CAN-Marg indices had the best explanatory power in standard regression models. The simplest ABSM-income quintile-detected 16 of 19 confirmed inequalities, more than any other single measure. CONCLUSIONS: At all ages, many pediatric health outcomes in Manitoba were associated with significant socioeconomic inequalities; while income quintile detected most, CAN-Marg composite indices had the best explanatory power.

Testing population-based performance measures identifies gaps in juvenile idiopathic arthritis (JIA) care.

BACKGROUND: The study evaluates Performance Measures (PMs) for Juvenile Idiopathic Arthritis (JIA): The percentage of patients with new onset JIA with at least one visit to a pediatric rheumatologist in the first year of diagnosis (PM1); and the percentage of patients with JIA under rheumatology care seen in follow-up at least once per year (PM2). METHODS: Validated JIA case ascertainment algorithms were used to identify cases from provincial health administrative databases in Manitoba, Canada in patients < 16 years between 01/04/2005 and 31/03/2015. PM1: Using a 3-year washout period, the percentage of incident JIA patients with ≥1 visit to a pediatric rheumatologist in the first year was calculated. For each fiscal year, the proportion of patients expected to be seen in follow-up who had a visit were calculated (PM2). The proportion of patients with gaps in care of > 12 and > 14 months between consecutive visits were also calculated. RESULTS: One hundred ninety-four incident JIA cases were diagnosed between 01/04/2008 and 03/31/2015. The median age at diagnosis was 9.1 years and 71% were female. PM1: Across the years, 51-81% of JIA cases saw a pediatric rheumatologist within 1 year. PM2: Between 58 and 78% of patients were seen in yearly follow-up. Gaps > 12, and > 14, months were observed once during follow-up in 52, and 34%, of cases, and ≥ twice in 11, and 5%, respectively. CONCLUSIONS: Suboptimal access to pediatric rheumatologist care was observed which could lead to diagnostic and treatment delays and lack of consistent follow-up, potentially negatively impacting patient outcomes.

Multicentre randomised controlled trial protocol of urine CXCL10 monitoring strategy in kidney transplant recipients.

INTRODUCTION: Subclinical inflammation is an important predictor of death-censored graft loss, and its treatment has been shown to improve graft outcomes. Urine CXCL10 outperforms standard post-transplant surveillance in observational studies, by detecting subclinical rejection and early clinical rejection before graft functional decline in kidney transplant recipients. METHODS AND ANALYSIS: This is a phase ii/iii multicentre, international randomised controlled parallel group trial to determine if the early treatment of rejection, as detected by urine CXCL10, will improve kidney allograft outcomes. Incident adult kidney transplant patients (n~420) will be enrolled to undergo routine urine CXCL10 monitoring postkidney transplant. Patients at high risk of rejection, defined as confirmed elevated urine CXCL10 level, will be randomised 1:1 stratified by centre (n=250). The intervention arm (n=125) will undergo a study biopsy to check for subclinical rejection and biopsy-proven rejection will be treated per protocol. The control arm (n=125) will undergo routine post-transplant monitoring. The primary outcome at 12 months is a composite of death-censored graft loss, clinical biopsy-proven acute rejection, de novo donor-specific antibody, inflammation in areas of interstitial fibrosis and tubular atrophy (Banff i-IFTA, chronic active T-cell mediated rejection) and subclinical tubulitis on 12-month surveillance biopsy. The secondary outcomes include decline of graft function, microvascular inflammation at 12 months, development of IFTA at 12 months, days from transplantation to clinical biopsy-proven rejection, albuminuria, EuroQol five-dimension five-level instrument, cost-effectiveness analysis of the urine CXCL10 monitoring strategy and the urine CXCL10 kinetics in response to rejection therapy. ETHICS AND DISSEMINATION: The study has been approved by the University of Manitoba Health Research Ethics Board (HS20861, B2017:076) and the local research ethics boards of participating centres. Recruitment commenced in March 2018 and results are expected to be published in 2023. De-identified data may be shared with other researchers according to international guidelines (International Committee of Medical Journal Editors [ICJME]). TRIAL REGISTRATION NUMBER: NCT03206801; Pre-results.

Trends in Population-Based Incidence and Prevalence of Juvenile Idiopathic Arthritis in Manitoba, Canada.

OBJECTIVE: To estimate the incidence and prevalence of juvenile idiopathic arthritis (JIA) in children ages <16 years in the province of Manitoba, Canada, and to determine changes in estimates between 2000 and 2012. METHODS: JIA cases were ascertained from the administrative health data of Manitoba, using a validated case-finding algorithm. Annual incidence and prevalence rates were estimated using a generalized linear model with generalized estimating equations (GEEs), adjusting for sociodemographic characteristics. Changes in estimates were tested using piecewise regression models. RESULTS: A total of 455 cases of JIA prevalence met the inclusion criteria. Sex- and age-adjusted incidence estimates were 14.01 (95% confidence interval [95% CI] 13.52, 14.53) in 2000/2001 and 9.18 (95% CI 8.56, 9.85) in 2010/2011. Prevalence estimates were 65.33 (95% CI 63.87, 66.83) in 2000/2001 and 59.61 (95% CI 58.17, 61.08) in 2010/2011. A linear piecewise model provided the best fit to the data. There was a significant decrease in prevalence over the study period (-0.18 [95% CI -0.35, -0.02]; P = 0.0292) but no statistically significant change in incidence (-0.46 [95% CI -0.94, 0.01]; P = 0.0571). Sex-stratified models revealed a decrease for males in both prevalence (estimate -0.54 [95% CI -0.84, -10.25]; P = 0.0003) and incidence (estimate -1.02 [95% CI -2.02, -0.04]; P = 0.0439); there were no changes for females. CONCLUSION: Few population-based longitudinal epidemiologic studies of JIA have been conducted. Our findings suggested a decrease in overall JIA prevalence, and in incidence and prevalence in men. Further research to validate these findings in other cohorts and to explore factors that contribute to this change will benefit future health care planning for JIA.

Association of Gestational Diabetes and Type 2 Diabetes Exposure In Utero With the Development of Type 2 Diabetes in First Nations and Non-First Nations Offspring.

Importance: Type 2 diabetes is increasing worldwide, disproportionately affecting First Nations (FN) people. Identifying early-life determinants of type 2 diabetes is important to address the intergenerational burden of illness. Objective: To investigate the association of in utero exposure to gestational diabetes and type 2 diabetes, stratified by FN status, with the development of type 2 diabetes in offspring. Design, Setting, and Participants: This cohort study was derived from the linkage of a pediatric diabetes clinical database and a population-based research data repository in Manitoba, Canada. Mother-infant dyads with a hospital birth or midwifery report in the data repository between April 1, 1984, and April 1, 2008, were identified. The dates of analysis were August through December 2017. Children identified with type 1 diabetes, monogenic diabetes, or secondary diabetes were excluded. Exposures: Primary exposures included maternal gestational diabetes or type 2 diabetes and FN status. Main Outcomes and Measures: The primary outcome was incident type 2 diabetes in offspring by age 30 years. Results: In this cohort study of 467 850 offspring (mean follow-up, 17.7 years; 51.2% male), FN status and diabetes exposure were associated with incident type 2 diabetes in offspring after adjustment for sex, maternal age, socioeconomic status, birth size, and gestational age. Type 2 diabetes exposure conferred a greater risk to offspring compared with gestational diabetes exposure (3.19 vs 0.80 cases per 1000 person-years, P < .001). Compared with no diabetes exposure, any diabetes exposure accelerated the time to the development of type 2 diabetes in offspring by a factor of 0.74 (95% CI, 0.62-0.90) for gestational diabetes and a factor of 0.50 (95% CI, 0.45-0.57) for type 2 diabetes. First Nations offspring had a higher risk compared with non-FN offspring (0.96 vs 0.14 cases per 1000 person-years, P < .001). First Nations offspring had accelerated type 2 diabetes onset by a factor of 0.52 (95% CI, 0.49-0.55) compared with non-FN offspring. Neither interaction between FN and type 2 diabetes (0.92; 95% CI, 0.80-1.05) nor interaction between FN and gestational diabetes (0.97; 95% CI, 0.77-1.20) was significant (P = .21 and P = .75, respectively). Conclusions and Relevance: Important differences exist in offspring risk based on type of diabetes exposure in utero. These findings have implications for future research and clinical practice guidelines, including early pregnancy screening and follow-up of the offspring.

The association of fatigue, pain, depression and anxiety with work and activity impairment in immune mediated inflammatory diseases.

Impairment in work function is a frequent outcome in patients with chronic conditions such as immune-mediated inflammatory diseases (IMID), depression and anxiety disorders. The personal and economic costs of work impairment in these disorders are immense. Symptoms of pain, fatigue, depression and anxiety are potentially remediable forms of distress that may contribute to work impairment in chronic health conditions such as IMID. The present study evaluated the association between pain [Medical Outcomes Study Pain Effects Scale], fatigue [Daily Fatigue Impact Scale], depression and anxiety [Hospital Anxiety and Depression Scale] and work impairment [Work Productivity and Activity Impairment Scale] in four patient populations: multiple sclerosis (n = 255), inflammatory bowel disease (n = 248, rheumatoid arthritis (n = 154) and a depression and anxiety group (n = 307), using quantile regression, controlling for the effects of sociodemographic factors, physical disability, and cognitive deficits. Each of pain, depression symptoms, anxiety symptoms, and fatigue individually showed significant associations with work absenteeism, presenteeism, and general activity impairment (quantile regression standardized estimates ranging from 0.3 to 1.0). When the distress variables were entered concurrently into the regression models, fatigue was a significant predictor of work and activity impairment in all models (quantile regression standardized estimates ranging from 0.2 to 0.5). These findings have important clinical implications for understanding the determinants of work impairment and for improving work-related outcomes in chronic disease.

Model-based methods for case definitions from administrative health data: application to rheumatoid arthritis.

OBJECTIVE: This research proposes a model-based method to facilitate the selection of disease case definitions from validation studies for administrative health data. The method is demonstrated for a rheumatoid arthritis (RA) validation study. STUDY DESIGN AND SETTING: Data were from 148 definitions to ascertain cases of RA in hospital, physician and prescription medication administrative data. We considered: (A) separate univariate models for sensitivity and specificity, (B) univariate model for Youden's summary index and (C) bivariate (ie, joint) mixed-effects model for sensitivity and specificity. Model covariates included the number of diagnoses in physician, hospital and emergency department records, physician diagnosis observation time, duration of time between physician diagnoses and number of RA-related prescription medication records. RESULTS: The most common case definition attributes were: 1+ hospital diagnosis (65%), 2+ physician diagnoses (43%), 1+ specialist physician diagnosis (51%) and 2+ years of physician diagnosis observation time (27%). Statistically significant improvements in sensitivity and/or specificity for separate univariate models were associated with (all p values <0.01): 2+ and 3+ physician diagnoses, unlimited physician diagnosis observation time, 1+ specialist physician diagnosis and 1+ RA-related prescription medication records (65+ years only). The bivariate model produced similar results. Youden's index was associated with these same case definition criteria, except for the length of the physician diagnosis observation time. CONCLUSION: A model-based method provides valuable empirical evidence to aid in selecting a definition(s) for ascertaining diagnosed disease cases from administrative health data. The choice between univariate and bivariate models depends on the goals of the validation study and number of case definitions.

Variation in estimated glomerular filtration rate at dialysis initiation in children.

BACKGROUND: Data guiding the timing of dialysis initiation in children are limited. We sought to determine current practice and secular trends in Canada with respect to the timing of dialysis initiation in children based on estimated glomerular filtration rate (eGFR). METHODS: This observational study included incident chronic dialysis patients aged ≤21 years identified from the Canadian Organ Replacement Register who started dialysis in Canada between January 2001 and December 2010 at any of the nine participating Canadian centers (n = 583). Youth were categorized utilizing CKiD Schwartz eGFR into ≥10.5 (higher) or <10.5 ml/min/1.73 m2 (lower) eGFR groups. Differences at dialysis initiation by facility and region were examined, and secular trends were determined. RESULTS: Median eGFR at dialysis initiation was 8.1 (interquartile range 5.4-11.0) ml/min/1.73 m2. Overall, 29 % of the patients started dialysis with an eGFR of ≥10.5 ml/min/1.73 m2. The proportion of children starting with higher eGFR increased from 27.3 % in 2001 to 35.4 % in 2010 (p = 0.04) and differed by treatment facility (12-70 %; p = 0.0001). Factors associated with higher eGFR at dialysis initiation in the adjusted regression model were female sex [odds ratio (OR) 1.48; 95 % confidence interval (CI) 1.02-2.14], genetic cause of end-stage kidney disease (OR 2.77; 95 % CI 1.37-5.58) and living ≥50 km from treatment facility (OR 1.47; 95 % CI 1.01-2.14). CONCLUSIONS: One-third of the children were found to have initiated dialysis with an eGFR ≥10.5 ml/min/1.73 m2, however significant practice variation exists with respect to timing of dialysis initiation by treatment facility. More data is required to evaluate the clinical implications of this practice variation.

Perceptions of pediatric nephrologists regarding timing of dialysis initiation in children in Canada.

BACKGROUND: Significant practice variation exists in Canada with respect to timing of dialysis initiation in children. In the absence of evidence to guide practice, physicians' perceptions may significantly influence decision-making. OBJECTIVE: The objectives of this study are to (1) evaluate Canadian pediatric nephrologists' perceptions regarding dialysis initiation in children with chronic kidney disease (CKD) and (2) determine the factors guiding practice that may contribute to practice variation across Canada. DESIGN: This study was a cross-sectional online survey. SETTING: This study was done in academic pediatric nephrology centers in Canada. PARTICIPANTS: The participants of this study are pediatric nephrologists. MEASUREMENTS AND METHODS: An anonymous web-based survey was administered to pediatric nephrologists in Canada to evaluate perspectives and practice patterns regarding timing of dialysis initiation. We also explored the importance of estimated glomerular filtration rate (eGFR) vs. symptoms and the role of patient and provider factors influencing decisions. RESULTS: Thirty-five nephrologists (59 %) completed the survey. Most respondents care for advanced CKD patients in a multidisciplinary clinic (86 %) and no centers have a formal policy on timing of dialysis initiation. Seventy-five percent of centers follow <20 stage 4-5 CKD patients, and 9 % follow >30 patients. Discussions about dialysis initiation are generally informal (75 %) and the decision to start is made by the nephrologist (37 %) or a team (57 %). Fifty percent agreed GFR was important when deciding when to initiate dialysis, 41 % were neutral, and 9 % disagreed. Variability exists in the threshold that nephrologists considered early (vs. late) dialysis initiation: >20 (21 %), >15 (38 %), >12 (26 %), and >10 ml/min/1.73 m(2) (12 %). Practitioners however typically start dialysis in asymptomatic patients at eGFRs of 7-9 (9 %), 10-11 (41 %), 12-14 (38 %), and 15-19 (6 %) ml/min/1.73 m(2). Patient factors important in the decision to start dialysis for >90 % of nephrologists were fatigue, >10 % weight loss, nausea, increasing missed school, and awaiting a pre-emptive transplant. Age was only a factor for 56 %. LIMITATIONS: This study has a 59 % response rate. CONCLUSIONS: Variability exists in Canada regarding the importance and threshold of eGFR guiding the decision as to when to start dialysis in children, whereas patient symptoms are almost universally important to pediatric nephrologists' decision-making. Additional studies evaluating outcomes of children starting dialysis earlier vs. later are needed to standardize decision-making and care for children with kidney failure.

MISE EN CONTEXTE: Des différences significatives existent dans la pratique au Canada quant au moment où des traitements de dialyse devraient être entrepris chez les enfants souffrant d'insuffisance rénale. En absence de données probantes pour guider leur pratique, les différentes approches des néphrologues exerçant auprès de cette population jouent probablement un rôle majeur dans leur prise de décision. OBJECTIFS DE L'ÉTUDE: Dans un premier temps, l'étude visait à évaluer la perception des néphrologues canadiens en regard de l'amorce de traitements de dialyse chez les enfants atteints d'insuffisance rénale chronique (IRC). Ensuite, on a voulu déterminer les facteurs qui guident la pratique et qui font en sorte que des variations subsistent à cet égard dans la pratique en néphrologie pédiatrique à travers le Canada. CADRE ET TYPE D'ÉTUDE: Il s'agit d'un sondage transversal mené en ligne auprès des néphrologues pratiquant dans les unités pédiatriques des centres hospitaliers universitaires dans tout le Canada. MÉTHODOLOGIE: Un sondage accessible par le web, auquel les participants répondaient de façon anonyme, a été distribué aux spécialistes canadiens pratiquant en néphrologie pédiatrique. Ce sondage avait pour objectif d'évaluer les perceptions et les schémas de pratique relativement au moment le plus propice pour amorcer la dialyse. Le sondage explorait aussi l'importance du débit de filtration glomérulaire estimé (DFGe) par rapport aux symptômes ressentis par le patient dans la prise de décision. Finalement, nous avons tenté d'identifier les facteurs pouvant influencer le patient et son médecin traitant au moment de décider d'entreprendre des traitements de dialyse. RÉSULTATS: Tous les pédiatres-néphrologues pratiquant au Canada ont reçu le questionnaire. Toutefois, seulement 35 d'entre eux, soit un peu plus de la moitié (59 %), l'ont complété et renvoyé. La grande majorité des répondants (86 %) exerçaient au sein de cliniques multidisciplinaires, auprès de cas sévères d'IRC. Aucun des centres de soins où ces spécialistes pratiquent ne possédait de politique formelle quant au moment d'entreprendre des traitements de dialyse chez les patients suivis en néphrologie pédiatrique. Les trois quarts des centres de soins cités (75 %) suivaient moins de 20 cas d'IRC de stade 4 ou 5, alors que 9 % en suivaient plus de 30. Les répondants ont indiqué dans une proportion de 75 % que la discussion concernant l'amorce de la dialyse se déroulait de façon informelle. De plus, le sondage révèle que la décision d'amorcer la dialyse est prise par le néphrologue soignant seulement (37 % des cas) ou par une équipe (57 % des cas). La moitié des répondants (50 %) s'accordait pour dire que le DFGe était important dans leur prise de décision d'amorcer des traitements de dialyse chez leurs patients, 41 % avaient une opinion neutre à ce sujet alors que 9 % ne jugeaient pas cet élément important. Les pédiatres-néphrologues répondants sont partagés quant à la valeur seuil de DFGe qu'ils considèrent comme une amorce « hâtive ¼ de dialyse. Pour 21 % des répondants, cette valeur se situe à 20 ml/min/1,73 m2; pour 38 % elle se situe plutôt à 15 ml/min/1,73 m2; 26 % l'établissent à 12 ml/min/1,73 m2; alors que 12 % des répondants jugent l'amorce d'une dialyse dite « hâtive ¼ à un DFGe de 10 ml/min/1,73 m2. De façon générale, chez les patients asymptomatiques, la dialyse est amorcée lorsque le DFGe se situe entre 7 et 9 ml/min/1,73 m2 (9 % des cas), entre 10 et 11 ml/min/1,73 m2 (41 % des cas), entre 12 et 14 ml/min/1,73 m2 (38 % des cas) ou entre 15 et 19 ml/min/1,73 m2 (6 % des cas). Enfin, parmi les facteurs motivant les patients à entreprendre des traitements de dialyse, tels que rapportés par les répondants dans une proportion de plus de 90 %, on trouve : une sensation de fatigue, une perte de poids de plus de 10 %, des nausées, les absences répétées à l'école et l'attente d'une greffe rénale préventive. L'âge n'a été mentionné comme facteur que dans 56 % des cas. LIMITES DE L'ÉTUDE: Le taux de réponse au sondage relativement faible (59 %) limite la portée des résultats. CONCLUSIONS: En néphrologie pédiatrique, alors que les symptômes ressentis par les patients sont considérés de façon universelle dans la décision d'entreprendre une dialyse, les pédiatres-néphrologues canadiens ont des perceptions très différentes quant à la valeur seuil de DFGe qui devrait guider cette décision et à l'importance du rôle que ce paramètre devrait y jouer. Des études supplémentaires comparant les résultats chez les patients qui amorcent une dialyse dite hâtive par rapport à ceux de patients l'amorçant plus tard s'avèrent nécessaires pour établir des pratiques standardisées en matière de soins pour les enfants atteints d'insuffisance rénale.