1
|
Pharmacodynamics of rituximab in paediatric immune mediated diseases: B cell depletion and repopulation, effects on immunoglobulin levels and risk for infections. Clin Exp Rheumatol 2023; 41:2323-2330. [PMID: 37470239 DOI: 10.55563/clinexprheumatol/yqjz1s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 05/24/2023] [Indexed: 07/21/2023]
Abstract
OBJECTIVES Rituximab (RTX), used for treatment in paediatric immune-mediated diseases, can lead to hypogammaglobulinaemia and thus to an increased risk of infection, but data on these adverse effects in children are scarce. We aimed to describe the pharmacodynamics of RTX by time to B cell repopulation in paediatric immune-mediated diseases and to assess whether low post-RTX immunoglobulin levels were associated with frequency and severity of infections. METHODS Data of children with autoimmune diseases (AID), immune dysregulation (ID), haematological diseases (HD) and renal diseases (RD), including immunoglobulin levels pre-/post-RTX and occurrence of infections, who had received RTX at our centre were retrospectively collected. B cell depletion was defined as B cells <10 cells/μl. RESULTS Post-RTX B cell depletion was achieved in 45/49 patients. In 30/45 patients with B cell repopulation, median time to repopulation was 166 days (IQR 140-224): AID group (n=9) (183 days (IQR 156-239), ID group (n=6) 170 days (IQR 128-184), HD group (n=7) 139 days (IQR 127-294), RD group (n=7) 160 days (IQR 121-367). Severe infections leading to hospitalisation occurred in 7/52 (13.5%) patients: ID (n=3), HD (n=1), RD (n=3). After RTX treatment, 13/52 patients (25%) had low IgG levels for their age at least once, 11/13 had an infection during low IgG but only 2/13 had a severe infection. Low IgG was not associated with severe infection (p=0.459). CONCLUSIONS Time to B cell repopulation post-RTX ranged individually but did not significantly differ between paediatric patient groups. Severe infections were non-frequent and not associated with low (post-RTX) IgG levels.
Collapse
|
2
|
Corrigendum to "Successful kidney-alone transplantation in a patient with PH1 on combination RNA-interference therapy." Kidney International, 2023;104:203-204. Kidney Int 2023; 104:1038. [PMID: 37863627 DOI: 10.1016/j.kint.2023.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2023]
|
3
|
Weight loss and metabolic acidosis in a neonate: Answers. Pediatr Nephrol 2023; 38:2581-2584. [PMID: 36598597 DOI: 10.1007/s00467-022-05847-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 01/05/2023]
|
4
|
Weight loss and metabolic acidosis in a neonate: Questions. Pediatr Nephrol 2023; 38:2579-2580. [PMID: 36598596 DOI: 10.1007/s00467-022-05845-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 01/05/2023]
|
5
|
Successful kidney-alone transplantation in a patient with PH1 on combination RNA-interference therapy. Kidney Int 2023; 104:203-204. [PMID: 37349052 DOI: 10.1016/j.kint.2023.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 06/24/2023]
|
6
|
Plasma oxalate and glycolate concentrations in dialysis patients with and without primary hyperoxaluria type 1. Nephrol Dial Transplant 2023:7075896. [PMID: 36898675 DOI: 10.1093/ndt/gfad049] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
|
7
|
Glycolate oxidase inhibition by lumasiran varies between patients with primary hyperoxaluria type 1. Kidney Int 2023; 103:990-993. [PMID: 36871948 DOI: 10.1016/j.kint.2023.01.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/23/2023] [Accepted: 01/27/2023] [Indexed: 03/06/2023]
|
8
|
Speckle tracking echocardiography (STE) in patients with primary hyperoxularia type 1 (PH1). Eur Heart J Cardiovasc Imaging 2022. [DOI: 10.1093/ehjci/jeab289.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Introduction
Primary Hyperoxaluria type 1 (PH1) is a rare, inherited metabolic disorder of glyoxylate metabolism characterized by oxalate overproduction, leading to end-stage kidney disease (ESKD) in more than half of all patients. As renal function deteriorates the ability of the kidneys to excrete the excess of oxalate is increasingly compromised resulting in elevated concentrations of oxalate in the blood and progressive systemic deposition of calcium-oxalate crystals in virtually all tissues, a situation referred to as systemic oxalosis. A wide spectrum of cardiac abnormalities are reported in PH1 patients, including presymptomatic myocardial disease early in the disease course. We aimed to further determine cardiac manifestations in a heterogenous cohort of PH1 patients by conventional and speckle tracking echocardiography (STE).
Methods
Data from 38 genetically confirmed PH1 patients were included in this two-centre study and compared to age- and sex-matched controls. Comprehensive echocardiographic analysis (including STE) was performed. PH1 patients were subdivided in three groups based on stage of chronic kidney disease (CKD) and transplantation status (CKD1-4 (n = 24), CKD5 (n = 7) and post-liver transplantation (n = 7)).
Results
Left-ventricle ejection fraction (LV EF) was preserved in all subjects. PH1 patients had a decreased global longitudinal strain compared to healthy controls, with a mean difference of -2.28 (p < 0.001). In patients with CKD1-4 decreased LS values were solely found in all apical segments, with a mean difference of -5.3 (p < 0.001) as compared to healthy controls. In patients whom already progressed to end-stage kidney disease (ESKD, defined as CKD5) diastolic dysfunction is noted, with preserved systolic function.
Conclusion
Pre-symptomatic myocardial dysfunction is present in PH1 patients with mild renal impairment and relatively normal plasma oxalate values. This indicates that cardiac screening is warranted in all PH1 patients, irrespective of renal function.
Collapse
|
9
|
Assessment of nutritional status in children with kidney diseases-clinical practice recommendations from the Pediatric Renal Nutrition Taskforce. Pediatr Nephrol 2021; 36:995-1010. [PMID: 33319327 PMCID: PMC7910229 DOI: 10.1007/s00467-020-04852-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 10/03/2020] [Accepted: 11/06/2020] [Indexed: 02/07/2023]
Abstract
In children with kidney diseases, an assessment of the child's growth and nutritional status is important to guide the dietary prescription. No single metric can comprehensively describe the nutrition status; therefore, a series of indices and tools are required for evaluation. The Pediatric Renal Nutrition Taskforce (PRNT) is an international team of pediatric renal dietitians and pediatric nephrologists who develop clinical practice recommendations (CPRs) for the nutritional management of children with kidney diseases. Herein, we present CPRs for nutritional assessment, including measurement of anthropometric and biochemical parameters and evaluation of dietary intake. The statements have been graded using the American Academy of Pediatrics grading matrix. Statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs based on the clinical judgment of the treating physician and dietitian. Audit and research recommendations are provided. The CPRs will be periodically audited and updated by the PRNT.
Collapse
|
10
|
The dietary management of potassium in children with CKD stages 2-5 and on dialysis-clinical practice recommendations from the Pediatric Renal Nutrition Taskforce. Pediatr Nephrol 2021; 36:1331-1346. [PMID: 33730284 PMCID: PMC8084813 DOI: 10.1007/s00467-021-04923-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/18/2020] [Accepted: 01/05/2021] [Indexed: 02/07/2023]
Abstract
Dyskalemias are often seen in children with chronic kidney disease (CKD). While hyperkalemia is common, with an increasing prevalence as glomerular filtration rate declines, hypokalemia may also occur, particularly in children with renal tubular disorders and those on intensive dialysis regimens. Dietary assessment and adjustment of potassium intake is critically important in children with CKD as hyperkalemia can be life-threatening. Manipulation of dietary potassium can be challenging as it may affect the intake of other nutrients and reduce palatability. The Pediatric Renal Nutrition Taskforce (PRNT), an international team of pediatric renal dietitians and pediatric nephrologists, has developed clinical practice recommendations (CPRs) for the dietary management of potassium in children with CKD stages 2-5 and on dialysis (CKD2-5D). We describe the assessment of dietary potassium intake, requirements for potassium in healthy children, and the dietary management of hypo- and hyperkalemia in children with CKD2-5D. Common potassium containing foods are described and approaches to adjusting potassium intake that can be incorporated into everyday practice discussed. Given the poor quality of evidence available, a Delphi survey was conducted to seek consensus from international experts. Statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs, based on the clinical judgment of the treating physician and dietitian. These CPRs will be regularly audited and updated by the PRNT.
Collapse
|
11
|
Development and Validation of a New Gas Chromatography-Tandem Mass Spectrometry Method for the Measurement of Enrichment of Glyoxylate Metabolism Analytes in Hyperoxaluria Patients Using a Stable Isotope Procedure. Anal Chem 2020; 92:1826-1832. [PMID: 31867958 PMCID: PMC6977104 DOI: 10.1021/acs.analchem.9b03670] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Primary
hyperoxalurias (PH) are inborn errors of glyoxylate metabolism
characterized by an increase in endogenous oxalate production. Oxalate
overproduction may cause calcium-oxalate crystal formation leading
to kidney stones, nephrocalcinosis, and ultimately kidney failure.
Twenty-four hour urine oxalate excretion is an inaccurate measure
for endogenous oxalate production in PH patients and not applicable
in those with kidney failure. Treatment efficacy cannot be assessed
with this measure during clinical trials. We describe the development
and validation of a gas chromatography–tandem mass spectrometry
method to analyze the samples obtained following a stable isotope
infusion protocol of 13C2-oxalate and 1-13C-glycolate in both healthy individuals and PH patients.
Isotopic enrichments of plasma oxalate, glycolate, and glyoxylate
were measured on a gas chromatography–triple quadrupole mass
spectrometry system using ethylhydroxylamine and N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide
(MTBSTFA) for analyte derivatization. Method precision was good for
oxalate and glycolate (coefficients of variation [CV] were <6.3%
and <4.2% for inter- and intraday precision, respectively) and
acceptable for glyoxylate (CV <18.3% and <6.7% for inter- and
intraday precision, respectively). The enrichment curves were linear
over the specified range. Sensitivity was sufficient to accurately
analyze enrichments. This new method allowed calculation of kinetic
features of these metabolites, thus enabling a detailed analysis of
the various pathways involved in glyoxylate metabolism. The method
will further enhance the investigation of the metabolic PH derangements,
provides a tool to accurately assess the therapeutic efficacy of new
promising therapeutic interventions for PH, and could serve as a clinical
tool to improve personalized therapeutic strategies.
Collapse
|
12
|
Novel Assays to Distinguish Between Properdin-Dependent and Properdin-Independent C3 Nephritic Factors Provide Insight Into Properdin-Inhibiting Therapy. Front Immunol 2019; 10:1350. [PMID: 31263464 PMCID: PMC6590259 DOI: 10.3389/fimmu.2019.01350] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 05/28/2019] [Indexed: 01/01/2023] Open
Abstract
C3 glomerulopathy (C3G) is an umbrella classification for severe renal diseases characterized by predominant staining for complement component C3 in the glomeruli. The disease is caused by a dysregulation of the alternative pathway (AP) of the complement system. In more than half of C3G patients C3 nephritic factors (C3NeFs) are found. These autoantibodies bind to the AP C3 convertase, prolonging its activity. C3NeFs can be dependent or independent of the complement regulator properdin for their convertase-stabilizing function. However, studies to determine the properdin-dependency of C3NeFs are rare and not part of routine patient workup. Until recently, only supportive treatments for C3G were available. Complement-directed therapies are now being investigated. We hypothesized that patients with properdin-dependent C3NeFs may benefit from properdin-inhibiting therapy to normalize convertase activity. Therefore, in this study we validated two methods to distinguish between properdin-dependent and properdin-independent C3NeFs. These methods are hemolytic assays for measuring convertase activity and stability in absence of properdin. The first assay assesses convertase stabilization by patient immunoglobulins in properdin-depleted serum. The second assay measures convertase stabilization directly in patient serum supplemented with the properdin-blocking agent Salp20. Blood samples from 13 C3NeF-positive C3G patients were tested. Three patients were found to have properdin-dependent C3NeFs, whereas the C3NeF activity of the other ten patients was independent of properdin. The convertase-stabilizing activity in the samples of the patients with properdin-dependent C3NeFs disappeared in absence of properdin. These data indicate that inhibition of properdin in patients with properdin-dependent C3NeFs can normalize convertase activity and could represent a novel therapy for normalizing AP hyperactivity. Our assays provide a tool for identifying C3G patients who may benefit from properdin-inhibiting therapy and can be incorporated into standard C3G laboratory investigations.
Collapse
|
13
|
|
14
|
Diagnostic dilemmas in a girl with acute glomerulonephritis: Answers. Pediatr Nephrol 2018; 33:65-69. [PMID: 28280937 PMCID: PMC5700220 DOI: 10.1007/s00467-017-3626-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 02/04/2017] [Accepted: 02/07/2017] [Indexed: 11/26/2022]
|
15
|
Bioimpedance and Fluid Status in Children and Adolescents Treated With Dialysis. Am J Kidney Dis 2017; 69:428-435. [PMID: 28089477 DOI: 10.1053/j.ajkd.2016.10.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 10/09/2016] [Indexed: 11/11/2022]
Abstract
BACKGROUND Assessment of hydration status in patients with chronic kidney failure treated by dialysis is crucial for clinical management decisions. Dilution techniques are considered the gold standard for measurement of body fluid volumes, but they are unfit for day-to-day care. Multifrequency bioimpedance has been shown to be of help in clinical practice in adults and its use in children and adolescents has been advocated. We investigated whether application of multifrequency bioimpedance is appropriate for total-body water (TBW) and extracellular water (ECW) measurement in children and adolescents on dialysis therapy. STUDY DESIGN A study of diagnostic test accuracy. SETTING & PARTICIPANTS 16 young dialysis patients (before a hemodialysis session or after peritoneal dialysis treatment) from the Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy, and the Emma Children's Hospital-Academic Medical Center, Amsterdam, the Netherlands. INDEX TEST TBW and ECW volumes assessed by multifrequency bioimpedance. REFERENCE TESTS TBW and ECW volumes measured by deuterium and bromide dilution, respectively. RESULTS Mean TBW volumes determined by multifrequency bioimpedance and deuterium dilution were 19.2±8.7 (SD) and 19.3±8.3L, respectively; Bland-Altman analysis showed a mean bias between the 2 methods of -0.09 (95% limits of agreement, -2.1 to 1.9) L. Mean ECW volumes were 8.9±4.0 and 8.3±3.3L measured by multifrequency bioimpedance and bromide dilution, respectively; mean bias between the 2 ECW measurements was +0.6 (95% limits of agreement, -2.3 to 3.5). LIMITATIONS Participants ingested the deuterated water at home without direct supervision by investigators, small number of patients, repeated measurements in individual patients were not performed. CONCLUSIONS Multifrequency bioimpedance measurements were unbiased but imprecise in comparison to dilution techniques. We conclude that multifrequency bioimpedance measurements cannot precisely estimate TBW and ECW in children receiving dialysis.
Collapse
|
16
|
Eculizumab in Pediatric Dense Deposit Disease. Clin J Am Soc Nephrol 2015; 10:1773-82. [PMID: 26316621 DOI: 10.2215/cjn.01360215] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 07/01/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Dense deposit disease (DDD), a subtype of C3 glomerulopathy, is a rare disease affecting mostly children. Treatment options are limited. Debate exists whether eculizumab, a monoclonal antibody against complement factor C5, is effective in DDD. Reported data are scarce, especially in children. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS The authors analyzed clinical and histologic data of five pediatric patients with a native kidney biopsy diagnosis of DDD. Patients received eculizumab as therapy of last resort for severe nephritic or nephrotic syndrome with alternative pathway complement activation; this therapy was given only when the patients had not or only marginally responded to immunosuppressive therapy. Outcome measures were kidney function, proteinuria, and urine analysis. RESULTS In all, seven disease episodes were treated with eculizumab (six episodes of severe nephritic syndrome [two of which required dialysis] and one nephrotic syndrome episode). Median age at treatment start was 8.4 (range, 5.9-13) years. For three treatment episodes, eculizumab was the sole immunosuppressive treatment. In all patients, both proteinuria and renal function improved significantly within 12 weeks of treatment (median urinary protein-to-creatinine ratio of 8.5 [range, 2.2-17] versus 1.1 [range, 0.2-2.0] g/g, P<0.005, and eGFR of 58 [range, 17-114] versus 77 [range, 50-129] ml/min per 1.73 m(2), P<0.01). A striking finding was the disappearance of leukocyturia within 1 week after the first eculizumab dose in all five episodes with leukocyturia at treatment initiation. CONCLUSIONS In this case series of pediatric patients with DDD, eculizumab treatment was associated with reduction in proteinuria and increase in eGFR. Leukocyturia resolved within 1 week of initiation of eculizumab treatment. These results underscore the need for a randomized trial of eculizumab in DDD.
Collapse
|
17
|
The zebra among horses: extensive abnormalities in a kidney biopsy without clinical signs of kidney disease. Fabry's disease. Neth J Med 2014; 72:331-335. [PMID: 25319860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
|
18
|
KCNJ10 mutations display differential sensitivity to heteromerisation with KCNJ16. Nephron Clin Pract 2013; 123:7-14. [PMID: 24193250 DOI: 10.1159/000356353] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 10/16/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS Mutations in the inwardly-rectifying K(+)-channel KCNJ10/Kir4.1 cause autosomal recessive EAST syndrome (epilepsy, ataxia, sensorineural deafness and tubulopathy). KCNJ10 is expressed in the distal convoluted tubule of the kidney, stria vascularis of the inner ear and brain glial cells. Patients diagnosed clinically with EAST syndrome were genotyped and mutations in KCNJ10 were studied functionally. METHODS Patient DNA was amplified and sequenced, and new mutations were identified. Mutant and wild-type KCNJ10 constructs were cloned and heterologously expressed in Xenopus oocytes. Whole-cell K(+) currents were measured by 2-electrode voltage clamping and channel expression was analysed by Western blotting. RESULTS We identified 3 homozygous mutations in KCNJ10 (p.F75C, p.A167V and p.V91fs197X), with mutation p.A167V previously reported in a compound heterozygous state. Oocytes expressing wild-type human KCNJ10 showed inwardly rectified currents, which were significantly reduced in all of the mutants (p < 0.001). Specific inhibition of KCNJ10 currents by Ba(2+) demonstrated a large residual function in p.A167V only, which was not compatible with causing disease. However, co-expression with KCNJ16 abolished function in these heteromeric channels almost completely. CONCLUSION This study provides an explanation for the pathophysiology of the p.A167V KCNJ10 mutation, which had previously not been considered pathogenic on its own. These findings provide evidence for the functional cooperation of KCNJ10 and KCNJ16. Thus, in vitro ascertainment of KCNJ10 function may necessitate co-expression with KCNJ16.
Collapse
|
19
|
Abstract
Background Patients with unilateral MultiCystic Kidney Dysplasia (MCKD) or unilateral renal agenesis (URA) have a congenital solitary functioning kidney (CSFK) that is compensatory enlarged. The question whether this enlargement is due to increased nephron numbers and/or to nephron hypertrophy is unresolved. This question is of utmost clinical importance, since hypertrophy is associated with a risk of developing hypertension and proteinuria later in life with consequent development of CKD and cardiovascular disease. Methodology/Principal Findings In a cohort of 32,000 slaughter pigs, 7 congenital solitary functioning kidneys and 7 control kidneys were identified and harvested. Cortex volume was measured and with a 3-dimensional stereologic technique the number and volume of glomeruli was determined and compared. The mean total cortex volume was increased by more than 80% and the mean number of glomeruli per kidney was 50% higher in CSFKs than in a single control kidney, equaling 75% of the total nephron number in both kidneys of control subjects. The mean total glomerular volume in the CSFKs was not increased relative to the controls. Conclusions/Significance Thus, in pigs, compensatory enlargement of a CSFK is based on increased nephron numbers. Extrapolation of these findings to the human situation suggests that patients with a CSFK might not be at increased risk for developing hyperfiltration-associated renal and cardiovascular disease in later life due to a lower nephron number.
Collapse
|
20
|
Gain of glycosylation in integrin α3 causes lung disease and nephrotic syndrome. J Clin Invest 2012; 122:4375-87. [PMID: 23114595 DOI: 10.1172/jci64100] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 09/06/2012] [Indexed: 12/23/2022] Open
Abstract
Integrins are transmembrane αβ glycoproteins that connect the extracellular matrix to the cytoskeleton. The laminin-binding integrin α3β1 is expressed at high levels in lung epithelium and in kidney podocytes. In podocytes, α3β1 associates with the tetraspanin CD151 to maintain a functional filtration barrier. Here, we report on a patient homozygous for a novel missense mutation in the human ITGA3 gene, causing fatal interstitial lung disease and congenital nephrotic syndrome. The mutation caused an alanine-to-serine substitution in the integrin α3 subunit, thereby introducing an N-glycosylation motif at amino acid position 349. We expressed this mutant form of ITGA3 in murine podocytes and found that hyperglycosylation of the α3 precursor prevented its heterodimerization with β1, whereas CD151 association with the α3 subunit occurred normally. Consequently, the β1 precursor accumulated in the ER, and the mutant α3 precursor was degraded by the ubiquitin-proteasome system. Thus, these findings uncover a gain-of-glycosylation mutation in ITGA3 that prevents the biosynthesis of functional α3β1, causing a fatal multiorgan disorder.
Collapse
|
21
|
[Long term effects of Kawasaki disease]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2010; 154:A2121. [PMID: 21118585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Kawasaki Disease (KD) is an acute, self-limiting, vasculitis typically occurring in children under the age of five. Less than 5% of children with KD develop coronary aneurysms and require follow-up by a (paediatric) cardiologist. The majority of patients do not receive follow-up care. However, recent data suggest that the inflammation associated with KD has the potential to affect the entire cardiovascular system. Patients with a history of KD may have an increased risk of long-term cardiovascular sequelae. Therefore KD should be considered a cardiovascular risk factor.
Collapse
|
22
|
Who ever said size doesn't matter? The association between journal title length and impact factor. NDT Plus 2008; 1:126-127. [PMID: 28657050 PMCID: PMC5477907 DOI: 10.1093/ndtplus/sfm047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
23
|
Energy expenditure and balance following pediatric intensive care unit admission: a longitudinal study of critically ill children. Pediatr Crit Care Med 2006; 7:147-53. [PMID: 16531947 DOI: 10.1097/01.pcc.0000194011.18898.90] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Longitudinal comparison of prescribed energy, actually administered energy, and energy expenditure (EE) predicted by Schofield's equations to actual EE, as determined by daily indirect calorimetry measurements in critically ill children during the first 7 days following admission. DESIGN Observational study. SETTING Pediatric intensive care unit, high and medium care wards, in a university hospital. PATIENTS Forty-six mechanically ventilated and spontaneously breathing infants and children (0-18 yrs) who were admitted with sepsis or following major abdominal or thoracic surgery or trauma. INTERVENTIONS Daily indirect calorimetry measurements and assessment of energy balance. MEASUREMENTS AND MAIN RESULTS Energy balance studies were performed for a total of 298 admission days in 13 sepsis, 27 surgery, and 6 trauma patients. Indirect calorimetry measurements were performed on 89% of the days. Mean measured EE was 44.6 +/- 15 kcal/kg.d and equaled predicted EE (44.2 +/- 12 kcal/kg.d; p = .56). Measured EE did not change over time, neither overall nor in diagnostic subgroups. Overall, median (range) administered energy was 31.1 (0-119) kcal/kg.d, which was significantly lower than measured EE (p < .001) and predicted EE (p < .001). Patients were underfed on 60% of days and overfed on 28% of days. Administered energy rose significantly in the course of admission, independently of diagnostic category, and did not differ from prescribed energy (p = .42). Energy intake was significantly higher in sepsis patients than in surgery and trauma patients during the whole course of the study (p < .01). The cumulative energy balance was positive only in sepsis patients. The administration of parenteral feeding was the single significant factor determining energy intake in mixed-effect modeling. CONCLUSIONS Measured EE was stable and not significantly different from predicted values over the course of hospitalization. Underfeeding was frequently present and mainly due to prescription and administration of energy amounts inferior to measured EE values in enterally fed patients.
Collapse
|
24
|
[Icterus prolongatus is a reason for laboratory investigation, also in breastfed neonates]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 2006; 150:461; author reply 461. [PMID: 16538851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
|
25
|
Simple and accurate assessment of energy expenditure in ventilated paediatric intensive care patients. Clin Nutr 2005; 23:657-63. [PMID: 15297103 DOI: 10.1016/j.clnu.2003.11.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2003] [Accepted: 11/04/2003] [Indexed: 01/18/2023]
Abstract
AIMS To assess validity and reliability of energy expenditure measurements with a short Douglas bag protocol compared to the standard metabolic monitor in a paediatric intensive care setting. METHODS 51 paired measurements were performed in 14 ventilated patients (age 0-18 years) with sepsis, trauma or following major surgery. Measured data were compared mutually and compared to Schofield equations using Bland-Altman analysis. RESULTS Comparing Douglas bag (3.21 +/- 1.43 MJ/day) and metabolic monitor (3.15 +/- 1.49 MJ/day) we found bias in energy expenditure of -0.06 (equal to -2%, NS) with limits of agreement of -0.5 to 0.4 MJ/day (equal to -16% to +13%). Intra-measurement variability (coefficient of variation) was within 10% for both methods. Both the metabolic monitor and Douglas bag showed significant bias compared to Schofield equations (3.39 +/-1.64 MJ/day) of -7% (P < 0.01) and -5% (P < 0.05), respectively, with wide limits of agreement: metabolic monitor vs. Schofield: -37% to +22%, Douglas bag vs. Schofield: -37% to +26%. CONCLUSIONS The Douglas bag method compared favourably to the metabolic monitor where Schofield equations failed to predict individual energy expenditure. Considering its low cost, this renders the short and simple Douglas bag method a robust measure and a routinely applicable instrument for tailored nutritional assessment in critically ill children.
Collapse
|
26
|
Minimal sampling protocol for accurate estimation of urea production: a study with oral [13C]urea in fed and fasted piglets. Clin Nutr 2005; 24:97-104. [PMID: 15681107 DOI: 10.1016/j.clnu.2004.07.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Accepted: 07/26/2004] [Indexed: 11/28/2022]
Abstract
BACKGROUND & AIMS An oral [13C]urea protocol may provide a simple method for measurement of urea production. The validity of single pool calculations in relation to a reduced sampling protocol was assessed. METHODS In eight fed and five fasted piglets, plasma urea enrichments from a 10 h sampling protocol were measured following an intragastric [13C]urea bolus. Blood [13C]bicarbonate was measured to trace gut [13C]urea oxidation. Two-compartment and regression (single pool) computations were performed. Pool sizes were compared to urea distribution over total body water (TBW). Shorter protocol duration was tested in regression simulations. RESULTS Differences in urea kinetics between fed and fasted piglets did not reach statistical significance. Mean (+/-SE) urea pool from TBW times plasma urea concentration was 2.2+/-0.16 mmol kg(-1). Two-compartment modelling yielded similar results for pool size (despite the oxidation of a small amount of urea tracer). Urea appearance rate was 306+/-18 micromol kg(-1)h(-1). Regression calculations overestimated urea appearance rate vs. compartmental model (P<0.05). When samples <2 h were discarded, results were comparable to compartmental calculations even if protocol length was 6 h (325+/-24 micromol kg(-1)h(-1), NS). CONCLUSIONS Regression calculations using plasma enrichments sampled between 2 and 6 h after oral [13C]urea administration provide accurate rates of urea production, and are not affected by tracer oxidation.
Collapse
|
27
|
Nutritional support in 111 pediatric intensive care units: a European survey. Intensive Care Med 2004; 30:1807-13. [PMID: 15197431 DOI: 10.1007/s00134-004-2356-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Accepted: 05/21/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To study current strategies in nutritional management of pediatric intensive care units (PICUs) in Europe, focusing on energy requirements. DESIGN AND SETTING Survey by a 35-item questionnaire sent to representatives of 242 PICUs in 28 countries. Addresses were obtained from national PICU associations and the members' list of the European Society of Pediatric and Neonatal Intensive Care. PARTICIPANTS Staff members of 111 European PICUs (46%) from 24 countries. MEASUREMENTS AND RESULTS Predominantly physicians were reported to be responsible for nutritional support. In 73% of PICUs a multidisciplinary nutritional team was available. In most PICUs daily energy requirements were estimated using weight, age, predictive equations and correction factors. In 17% of PICUs energy expenditure was regularly measured by indirect calorimetry. Nutritional status was mostly assessed by weight, physical examination, and a wide range of biochemical blood parameters. Approximately 70% of PICUs used dedicated software for nutritional support. A similar percentage of PICUs regarded "nutrition" as a research topic and part of the residents' training program. CONCLUSIONS Most European PICUs regard nutritional support as an important aspect of patient care, as shown by the presence of nutritional teams, software, research, and education. However, energy requirements of pediatric intensive care patient were based predominantly on estimations rather than on measurements.
Collapse
|
28
|
Determination of 13C and 15N enrichments of urea in plasma by gas chromatography-combustion isotope ratio mass spectrometry and gas chromatography-mass spectrometry using the 2-methoxypyrimidine derivative. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 791:399-405. [PMID: 12798200 DOI: 10.1016/s1570-0232(03)00257-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We describe a GC-MS and GC-c-IRMS method for the determination of labeled urea tracer enrichments in plasma as a result of combined 13C- and 15N(2)-urea infusion experiments in piglets. Urea was converted into 2-methoxypyrimidine, a stable derivative, suited for analyses by both GC-MS and GC-c-IRMS. Using calibration curves for the respective working ranges (13C-urea: 0-1% APE; 15N(2)-urea: 0-7% MPE) enrichments were established in single point measurements; for 15N(2)-urea as values+/-0.15% MPE (95% confidence interval); for 13C-urea as values+/-0.02% APE (95% confidence interval). 15N(1)-urea enrichments were determined by measurement of the same sample with GC-c-IRMS and GC-MS. Subtraction of the 13C specific GC-c-IRMS data from the nondiscriminating GC-MS data for the sum of 13C- and 15N(1)-urea resulted in 15N(1)-urea enrichments+/-0.15% MPE (95% confidence interval). Application of the method in a combined 13C-urea bolus and 15N(2)-urea primed constant infusion experiment in piglet was demonstrated.
Collapse
|