Chronic kidney disease (CKD) is a life-long condition associated with substantial morbidity and premature death due to complications from a progressive decrease in kidney function. The incidence and ...prevalence of all stages of CKD in children continues to increase worldwide. Between 2000 and 2008, the kidney replacement therapy incidence rate in those aged 0-19 years increased 5.9% to 15 per million population, highlighting the importance of CKD research in children. Many comorbid conditions seen in adults with CKD, including cardiovascular disease and cognitive impairment, also are highly prevalent in children, implicitly demonstrating the crucial need for initiating therapy early to improve health outcomes in children with CKD. The CKiD (Chronic Kidney Disease in Children) Study is a prospective cohort study of 586 children aged 1-16 years with an estimated glomerular filtration rate of 30-90 mL/min/1.73 m2 . Since its inception, CKiD has identified risk factors for CKD progression and cardiovascular disease in children with CKD and highlighted the effects of CKD on outcomes unique to children, including neurocognitive development and growth. This review summarizes the findings to date, illustrating the spectrum of CKD-associated complications in children and emphasizing areas requiring further investigation. Taken in sum, these elements stress that initiating treatment at an early age is essential for reducing long-term morbidity and mortality in children with CKD.
The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease for patients not receiving dialysis represents an ...update to the KDIGO 2012 guideline on this topic. Development of this guideline update followed a rigorous process of evidence review and appraisal. Guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence. The strength of recommendations is based on the “Grading of Recommendations Assessment, Development and Evaluation” (GRADE) approach. The scope includes topics covered in the original guideline, such as optimal blood pressure targets, lifestyle interventions, antihypertensive medications, and specific management in kidney transplant recipients and children. Some aspects of general and cardiovascular health, such as lipid and smoking management, are excluded. This guideline also introduces a chapter dedicated to proper blood pressure measurement since all large randomized trials targeting blood pressure with pivotal outcomes used standardized preparation and measurement protocols adhered to by patients and clinicians. Based on previous and new evidence, in particular the Systolic Blood Pressure Intervention Trial (SPRINT) results, we propose a systolic blood pressure target of less than 120 mm Hg using standardized office reading for most people with chronic kidney disease (CKD) not receiving dialysis, the exception being children and kidney transplant recipients. The goal of this guideline is to provide clinicians and patients a useful resource with actionable recommendations supplemented with practice points. The burden of the recommendations on patients and resources, public policy implications, and limitations of the evidence are taken into consideration. Lastly, knowledge gaps and recommendations for future research are provided.
Using data (2655 observations from 928 participants) from the Chronic Kidney Disease in Children Study, we developed and internally validated new glomerular filtration rate estimating equations for ...clinical use in children and young adults: two forms of K × heigh(ht) / serum creatinine(sCr) and two forms of K × 1 / cystatin C(cysC). For each marker, one equation used a sex-dependent K; in the other, K is sex-and age-dependent. Glomerular filtration rate (GFR) was measured directly by plasma iohexol disappearance. The equations using ht⁄sCr had sex-specific constants of 41.8 for males and 37.6 for females. In the age- dependent models, K increased monotonically for children 1-18 years old and was constant for young adults 18-25 years. For males, K ranged from 35.7 for one-year-olds to 50.8 for those 18 and older. For females, the values of K ranged from 33.1 to 41.4. Constant K values for cystatin-C equations were 81.9 for males and 74.9 for females. With age-dependency, K varied non-monotonically with the highest values at age 15 for males (K of 87.2) and 12 years for females (K of 79.9). Use of an age-dependent K with ht/sCr models reduced average bias, notably in young children and young adults; age-dependent cystatin-C models produced similar agreement to using a constant K in children under 18 years, but reduced bias in young adults. These age-dependent proposed equations were evaluated alongside estimated GFRs from 11 other published equations for pediatrics and young adults. Only our proposed equations yielded non- significant bias and within 30% accuracy values greater than 85% in both the pediatric and young adult subpopulations.
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Purpose Kidney stone disease has become increasingly common during childhood and adolescence. However, the rate of symptomatic kidney stone recurrence for pediatric patients is uncertain. We sought ...to determine the recurrence rate of symptomatic kidney stones in a cohort of children with incident symptomatic nephrolithiasis. Materials and Methods We performed a retrospective cohort study of patients 3 to 18 years old without anatomical abnormalities or genetic causes of nephrolithiasis who presented with a first symptomatic kidney stone between 2008 and 2014. We determined recurrence rates of symptomatic nephrolithiasis, defined as a new kidney stone on ultrasound and/or computerized tomogram associated with pain and/or vomiting. We also estimated associations between completing 24-hour urinalysis and symptomatic kidney stone recurrence using Kaplan-Meier curves and multivariable Cox regression models. Results A total of 285 children with a median age of 14.8 years (IQR 11.3–16.6) at nephrolithiasis diagnosis were followed for 492 person-years. A total of 86 symptomatic recurrent stones developed in 68 patients (24%) during the followup period. The probability of symptomatic stone recurrence was 50% at 3 years after the index kidney stone. Median time to stone recurrence was 3 years at the first recurrence and 5 years at the second. Adjusting for confounders including adherence to followup, completing a 24-hour urinalysis after a kidney stone episode was associated with a 60% decreased risk of recurrence (hazard ratio 0.40, 95% CI 0.18–0.91). Conclusions The risk of kidney stone recurrence is high during childhood, with approximately 50% of children presenting with symptomatic recurrence within 3 years of the first stone. The role and usefulness of analyzing 24-hour urine chemistries in decreasing kidney stone recurrence should be explored in future prospective studies.
Background Hyperuricemia is associated with essential hypertension in children. No previous studies have evaluated the effect of hyperuricemia on progression of chronic kidney disease (CKD) in ...children. Study Design Prospective observational cohort study. Setting & Participants Children and adolescents (n = 678 cross-sectional; n = 627 longitudinal) with a median age of 12.3 (IQR, 8.6-15.6) years enrolled at 52 North American sites of the CKiD (CKD in Children) Study. Predictor Serum uric acid level (<5.5, 5.5-7.5, and >7.5 mg/dL). Outcomes Composite end point of either >30% decline in glomerular filtration rate (GFR) or initiation of renal replacement therapy. Measurements Age, sex, race, blood pressure status, GFR, CKD cause, urine protein-creatinine ratio (<0.5, 0.5-<2.0, and ≥2.0 mg/mg), age- and sex-specific body mass index > 95th percentile, use of diuretics, and serum uric acid level. Results Older age, male sex, lower GFR, and body mass index > 95th percentile were associated with higher uric acid levels. 162, 294, and 171 participants had initial uric acid levels < 5.5, 5.5 to 7.5, or >7.5 mg/dL, respectively. We observed 225 instances of the composite end point over 5 years. In a multivariable parametric time-to-event analysis, compared with participants with initial uric acid levels < 5.5 mg/dL, those with uric acid levels of 5.5 to 7.5 or >7.5 mg/dL had 17% shorter (relative time, 0.83; 95% CI, 0.62-1.11) or 38% shorter (relative time, 0.62; 95% CI, 0.45-0.85) times to event, respectively. Hypertension, lower GFR, glomerular CKD cause, and elevated urine protein-creatinine ratio were also associated with faster times to the composite end point. Limitations The study lacked sufficient data to examine how use of specific medications might influence serum uric acid levels and CKD progression. Conclusions Hyperuricemia is a previously undescribed independent risk factor for faster progression of CKD in children and adolescents. It is possible that treatment of children and adolescents with CKD with urate-lowering therapy could slow disease progression.
•A fully automatic segment method for clinical ultrasound kidney images.•End-to-end learning of boundary detection and pixelwise classification networks.•Achieved significantly better performance ...than pixelwise classification networks.•Data-augment improved the segmentation performance.
It remains challenging to automatically segment kidneys in clinical ultrasound (US) images due to the kidneys’ varied shapes and image intensity distributions, although semi-automatic methods have achieved promising performance. In this study, we propose subsequent boundary distance regression and pixel classification networks to segment the kidneys automatically. Particularly, we first use deep neural networks pre-trained for classification of natural images to extract high-level image features from US images. These features are used as input to learn kidney boundary distance maps using a boundary distance regression network and the predicted boundary distance maps are classified as kidney pixels or non-kidney pixels using a pixelwise classification network in an end-to-end learning fashion. We also adopted a data-augmentation method based on kidney shape registration to generate enriched training data from a small number of US images with manually segmented kidney labels. Experimental results have demonstrated that our method could automatically segment the kidney with promising performance, significantly better than deep learning-based pixel classification networks.
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New Equations to Estimate GFR in Children with CKD SCHWARTZ, George J; MUNOZ, Alvaro; SCHNEIDER, Michael F ...
Journal of the American Society of Nephrology,
03/2009, Letnik:
20, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The Schwartz formula was devised in the mid-1970s to estimate GFR in children. Recent data suggest that this formula currently overestimates GFR as measured by plasma disappearance of iohexol, likely ...a result of a change in methods used to measure creatinine. Here, we developed equations to estimate GFR using data from the baseline visits of 349 children (aged 1 to 16 yr) in the Chronic Kidney Disease in Children (CKiD) cohort. Median iohexol-GFR (iGFR) was 41.3 ml/min per 1.73 m(2) (interquartile range 32.0 to 51.7), and median serum creatinine was 1.3 mg/dl. We performed linear regression analyses assessing precision, goodness of fit, and accuracy to develop improvements in the GFR estimating formula, which was based on height, serum creatinine, cystatin C, blood urea nitrogen, and gender. The best equation was: GFR(ml/min per 1.73 m(2))=39.1height (m)/Scr (mg/dl)(0.516) x 1.8/cystatin C (mg/L)(0.294)30/BUN (mg/dl)(0.169)1.099(male)height (m)/1.4(0.188). This formula yielded 87.7% of estimated GFR within 30% of the iGFR, and 45.6% within 10%. In a test set of 168 CKiD patients at 1 yr of follow-up, this formula compared favorably with previously published estimating equations for children. Furthermore, with height measured in cm, a bedside calculation of 0.413*(height/serum creatinine), provides a good approximation to the estimated GFR formula. Additional studies of children with higher GFR are needed to validate these formulas for use in screening all children for CKD.
Glomerular filtration rate (GFR) assesses kidney function. GFR is measured by renal clearance techniques; inulin clearance is the gold standard but is not easily measured. Thus, other methods to ...determine GFR have been utilized. Endogenous creatinine clearance (CrCl) is the most widely used, but creatinine secretion falsely elevates GFR. Cimetidine inhibits creatinine secretion, such that CrCl equals GFR, provided there are no difficulties with bladder emptying. Estimation of GFR from serum creatinine (e.g. Schwartz formula) is useful clinically; however, such formulae have not been updated for enzymatic creatinine autoanalyzers. Cystatin C, a small protein, is produced at a relatively constant rate and is reabsorbed in the proximal tubule. Cystatin C may be more sensitive than creatinine in detecting a reduction in GFR, but further studies are needed to prove this. Single injection (plasma) clearance techniques are the most precise measures of GFR. Iohexol is an exogenous marker that is comparable to inulin and (51)Cr-EDTA and can be measured by high-performance liquid chromatography (HPLC). Our pilot and the Chronic Kidney Disease in Children (CKiD) North American studies show that iohexol can accurately measure GFR using a four-point plasma disappearance curve national studies show that iohexol can accurately measure GFR using a four-point plasma disappearance curve (10, 30, 120, and 300 min) or, in most cases, a two-point disappearance time (120 and 300 min).
Background Neurocognitive dysfunction is a known complication in children with chronic kidney disease (CKD). However, less is known about putative mechanisms or modifiable risk factors. The objective ...of this study was to characterize and determine risk factors for cognitive dysfunction in children, adolescents, and young adults with CKD compared with controls. Study Design Cross-sectional study. Setting & Participants The Neurocognitive Assessment and Magnetic Resonance Imaging Analysis of Children and Young Adults With Chronic Kidney Disease (NiCK) Study included 90 individuals aged 8 to 25 years with CKD compared with 70 controls. Predictors CKD versus control, estimated glomerular filtration rate (eGFR), ambulatory blood pressure. Outcomes Performance on neurocognitive assessment with relevant tests grouped into 11 domains defined a priori by expert opinion. Results of tests were converted to age-normalized z scores. Measurements Each neurocognitive domain was analyzed through linear regression, adjusting for eGFR and demographic and clinical variables. For domains defined by multiple tests, the median z score of tests in that domain was used. Results We found significantly poorer performance in multiple areas of neurocognitive function among individuals with CKD compared with controls. Particular deficits were seen in domains related to attention, memory, and inhibitory control. Adjusted for demographic and clinical factors, we found lower performance in multiple domains with decreasing eGFRs (attention: β = 0.053, P = 0.02; visual spatial: β = 0.062, P = 0.02; and visual working memory: β = 0.069, P = 0.04). Increased diastolic load and decreased diastolic nocturnal dipping on ambulatory blood pressure monitoring were independently associated with impairments in neurocognitive performance. Limitations Unable to assess changes in neurocognitive function over time, and neurocognitive tests were grouped into predetermined neurocognitive domains. Conclusions Lower eGFR in children, adolescents, and young adults is associated with poorer neurocognitive performance, particularly in areas of attention, memory, and inhibitory control. Hypertension identified on ambulatory blood pressure monitoring may be an important risk factor, illustrating that neurocognitive function is an area of target-organ damage in CKD.
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