A pragmatic, open-label, randomized controlled trial of Plasma-Lyte-148 versus standard intravenous fluids in children receiving kidney transplants (PLUTO).

Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplant. This is partly because doctors give very large volumes of artificial fluids to keep the new kidney working. When severe, fluid imbalance can lead to seizures, cerebral edema and death. In this pragmatic, open-label, randomized controlled trial, we randomly assigned (1:1) pediatric kidney transplant recipients to Plasma-Lyte-148 or standard of care perioperative intravenous fluids (predominantly 0.45% sodium chloride and 0.9% sodium chloride solutions). We then compared clinically significant electrolyte and acid-base abnormalities in the first 72 hours post-transplant. The primary outcome, acute hyponatremia, was experienced by 53% of 68 participants in the Plasma-Lyte-148 group and 58% of 69 participants in the standard fluids group (odds ratio 0·77 (0·34 - 1·75)). Five of 16 secondary outcomes differed with Plasma-Lyte-148: hypernatremia was significantly more frequent (odds ratio 3·5 (1·1 - 10·8)), significantly fewer changes to fluid prescriptions were made (rate ratio 0·52 (0·40-0·67)), and significantly fewer participants experienced hyperchloremia (odds ratio 0·17 (0·07 - 0·40)), acidosis (odds ratio 0·09 (0·04 - 0·22)) and hypomagnesemia (odds ratio 0·21 (0·08 - 0·50)). No other secondary outcomes differed between groups. Serious adverse events were reported in 9% of participants randomized to Plasma-Lyte-148 and 7% of participants randomized to standard fluids. Thus, perioperative Plasma-Lyte-148 did not change the proportion of children who experienced acute hyponatremia compared to standard fluids. However fewer fluid prescription changes were made with Plasma-Lyte-148, while hyperchloremia and acidosis were less common.

Decline in Left Ventricular Early Systolic Function with Worsening Kidney Function in Children with Chronic Kidney Disease: Insights from the 4C and HOT-KID Studies.

INTRODUCTION: Adults with childhood-onset chronic kidney disease (CKD) have an increased risk of cardiovascular disease. First-phase ejection fraction (EF1), a novel measure of early systolic function, may be a more sensitive marker of left ventricular dysfunction than other markers in children with CKD. OBJECTIVE: To examine whether EF1 is reduced in children with CKD. METHODS: Children from the 4C and HOT-KID studies were stratified according to estimated glomerular filtration rate (eGFR). The EF1 was calculated from the fraction of left ventricular (LV) volume ejected up to the time of peak aortic flow velocity. RESULTS: The EF1 was measured in children ages 10.9 ± 3.7 (mean ± SD) years, 312 with CKD and 63 healthy controls. The EF1 was lower, while overall ejection fraction was similar, in those with CKD compared with controls and decreased across stages of CKD (29.3% ± 3.7%, 23.5% ± 4.5%, 19.8% ± 4.0%, 18.5% ± 5.1%, and 16.7% ± 6.6% in controls, CKD 1, 2, 3, and ≥ 4, respectively, P < .001). The relationship of EF1 to eGFR persisted after adjustment for relevant confounders (P < .001). The effect size for association of measures of LV structure or function with eGFR (SD change per unit change in eGFR) was greater for EF1 (ß = 0.365, P < .001) than for other measures: LV mass index (ß = -0.311), relative wall thickness (ß = -0.223), E/e' (ß = -0.147), and e' (ß = 0.141) after adjustment for confounders in children with CKD. CONCLUSIONS: Children with CKD exhibit a marked and progressive decline in EF1 with falling eGFR. This suggests that EF1 is a more sensitive marker of LV dysfunction when compared to other structural or functional measures and that early LV systolic function is a key feature in the pathophysiology of cardiac dysfunction in CKD.

Etiological Profile, Targeted Levothyroxine Dosing and Impact of Partial Newborn Screening in Congenital Hypothyroidism-A Single Centre Experience.

Background: Congenital hypothyroidism (CH) is the most common cause of preventable intellectual disability. Newborn screening (NBS) for CH has been in vogue in many parts of the world since 1970, but despite its well-known benefits, many developing countries including India have not been able to establish universal NBS for CH till date. Objective: The aim of this study was to review the clinical aspects of congenital hypothyroidism in a tertiary care university referral teaching hospital, focusing on aetiology of CH, predictors of permanence, optimal targeted dose strategies based on aetiology and the effect of newborn screening on the time to diagnosis. Material and Methods: The electronic medical records of 233 children with CH referred to our centre between January 2009 and December 2019 were analysed. A partial NBS was established in the state in 2012. Results: Dyshormonogenesis (57.5%) was the most common aetiology of CH. The incidence of transient CH in children with a gland in situ (GIS) was 35%. Levothyroxine (LT-4) dose of >2.75 µg/kg/day (sensitivity 76.5, specificity 72), >2.15 µg/kg/day (sensitivity 82.4, specificity 61.9) and >1.85 µg/kg/day (sensitivity 76.5, specificity 61.9) at years 1, 2 and 3, respectively, were predictors of permanent CH. An initial LT-4 dose ≥8 µg/kg was sufficient and very seldom led to undertreatment in children with dyshormonogenesis. On the contrary, even doses ≥13 mcg/kg/day led to frequent undertreatment in children with thyroid dysgenesis. After the introduction of newborn screening, the median age at diagnosis came down from 45 days (IQR 14-180 days) to ten days (IQR 3-12 days). Conclusion: Targeted dosing based on aetiology of CH may be more appropriate to optimise outcomes. The time to diagnosis of CH reduced significantly after the adoption of even a partial NBS program highlighting the urgent need for implementation of the same in resource poor settings.

Rituximab-associated hypogammaglobulinemia in children with idiopathic nephrotic syndrome: results of an ESPN survey.

BACKGROUND: There is paucity of information on rituximab-associated hypogammaglobulinemia (HGG) and its potential infectious consequences in children treated for idiopathic nephrotic syndrome (INS). METHODS: A survey was distributed by the European Society Pediatric Nephrology to its members. It addressed the screening and management practices of pediatric nephrology units for recognizing and treating RTX-associated HGG and its morbidity and mortality. Eighty-four centers which had treated an overall 1328 INS children with RTX responded. RESULTS: The majority of centers administered several courses of RTX and continued concomitant immunosuppressive therapy. Sixty-five percent of centers routinely screened children for HGG prior to RTX infusion, 59% during, and 52% following RTX treatment. Forty-seven percent had observed HGG prior to RTX administration, 61% during and 47% >9 months following treatment in 121, 210, and 128 subjects respectively. Thirty-three severe infections were reported among the cohort of 1328 RTX-treated subjects, of whom 3 children died. HGG had been recognized in 30/33 (80%) of them. CONCLUSIONS: HGG in steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS) children is probably multifactorial and can be observed prior to RTX administration in children with SDNS/FRNS. Persistent HGG lasting >9 months from RTX infusion is not uncommon and may increase the risk of severe infections in this cohort. We advocate for the obligatory screening for HGG in children with SDNS/FRNS prior to, during, and following RTX treatment. Further research is necessary to identify risk factors for developing both HGG and severe infections before recommendations are made for its optimal management. A higher resolution version of the Graphical abstract is available as Supplementary information.

Evaluation of height centile growth patterns compared with parental-adjusted target height following kidney transplantation.

BACKGROUND: Early steroid withdrawal (ESW) improves growth following kidney transplant (KT). It is not known whether these children achieve target height within mid-parental height range post-KT. METHODS: Retrospective analysis of growth patterns of KT recipients following ESW in our center between 2009 and 2020 had minimum follow-up period of 12 months. RESULTS: Forty-eight (female 29.2%) KT recipients, median age 5.3 years at first KT, were included. At KT, 29 (60.4%) recipients had normal height (SDS≥-1.88) and in 23 (47.9%), the height was within their target height (parental-adjusted height SDS within ±1.55). The proportion of children achieving normal height at 1-, 2-, 3-, and 5-years post-KT (median 5.5 years) were 75%, 83.3%, 86.5%, and 88% respectively. The proportion of children achieving target height measured at the same intervals was 68.8%, 73.8%, 73%, and 80%, respectively. Children <6 years were most growth impaired at KT but were most likely to achieve target height within first-year post-KT (72%; p = .023). All 19 children with short stature at KT received dialysis. Three children received growth hormone post-KT. Children who did not achieve target height post-KT (n = 14), five had eGFR <60 mL/min/1.73 m2 , and eight were on corticosteroid therapy at latest follow-up. CONCLUSIONS: Although vast majority of children achieved normal height post-KT following ESW during the first 5 years post-KT, 20% of these children had not achieved their target height post-KT.

Tubulointerstitial nephritis and uveitis in children during the COVID-19 pandemic: report of four cases.

Tubulointerstitial nephritis and uveitis (TINU) is a rare autoimmune disorder often triggered by drugs and infections. Since the onset of the COVID-19 pandemic, we have observed an unusual cluster of paediatric cases. Four children (3 females) were diagnosed with TINU (median age 13 years) following a kidney biopsy and ophthalmologic assessment. Presenting symptoms included abdominal pain (3 cases), fatigue, weight loss and vomiting (2 cases). At presentation, median eGFR was 50.3 ml/min/1.73m2 (range 19.2-69.3). Anaemia was common (3 cases) with median haemoglobin of 10.45 g/dL (range 8.4-12.1). Two patients were hypokalaemic and 3 had non-hyperglycaemic glycosuria. Median urine protein:creatinine ratio was 117 mg/mmol (range 68-167). SARS-CoV-2 antibodies were detected in 3 cases at presentation. All were asymptomatic for COVID-19 with a negative PCR. Kidney function improved following high-dose steroids. However, disease relapse was observed during steroid tapering (2 cases) and upon discontinuation (2 cases). All patients responded well to further high dose steroids. Mycophenolate mofetil was introduced as a steroid-sparing agent. At latest follow up (range 11-16 months), median eGFR was 109.8 ml/min/1.73m2. All four patients continue on mycophenolate mofetil, with 2 patients applying topical steroids for uveitis. Our data suggest that SARS-CoV-2 infection might be a trigger for TINU.

Hyperparathyroidism Is an Independent Risk Factor for Allograft Dysfunction in Pediatric Kidney Transplantation.

Introduction: Little is known about the consequences of deranged chronic kidney disease-mineral and bone disorder (CKD-MBD) parameters on kidney allograft function in children. We examined a relationship between these parameters over time and allograft outcome. Methods: This registry study from the Cooperative European Paediatric Renal Transplant Initiative (CERTAIN) collected data at baseline, months 1, 3, 6, 9, and 12 after transplant; and every 6 months thereafter up to 5 years. Survival analysis for a composite end point of graft loss or estimated glomerular filtration rate (eGFR) ≤30 ml/min per 1.73 m2 or a ≥50% decline from eGFR at month 1 posttransplant was performed. Associations of parathyroid hormone (PTH), calcium, phosphate, and 25-hydroxyvitamin D (25(OH)D) with allograft outcome were investigated using conventional stratified Cox proportional hazards models and further verified with marginal structural models with time-varying covariates. Results: We report on 1210 patients (61% boys) from 16 European countries. The composite end point was reached in 250 grafts (21%), of which 11 (4%) were allograft losses. In the conventional Cox proportional hazards models adjusted for potential confounders, only hyperparathyroidism (hazard ratio [HR], 2.94; 95% confidence interval [CI], 1.82-4.74) and hyperphosphatemia (HR, 1.94; 95% CI, 1.28-2.92) were associated with the composite end point. Marginal structural models showed similar results for hyperparathyroidism (HR, 2.74; 95% CI, 1.71-4.38), whereas hyperphosphatemia was no longer significant (HR, 1.35; 95% CI, 0.87-2.09), suggesting that its association with graft dysfunction can be ascribed to a decline in eGFR. Conclusion: Hyperparathyroidism is a potential independent risk factor for allograft dysfunction in children.

Successful ABO and HLA incompatible kidney transplantation in children in the UK.

BACKGROUND: There is increasing evidence of good short-term and medium-term outcomes of ABO incompatible (ABOi) and HLA incompatible (HLAi) kidney transplantation with pre-transplant positive crossmatches in paediatric practice. However, there remain concerns regarding the higher risks of infective complications and antibody-mediated rejections. The aim of our study is to show longer-term follow-up on all ABOi and HLAi paediatric kidney transplant recipients (pKTR) in the UK. METHODS: Questionnaires specifying kidney transplant type, desensitisation requirement and kidney allograft function were sent to 13 paediatric nephrology centres that performed kidney transplantation in children and young people under 18 years of age who received an ABOi and/or HLAi transplant between 1 January 2006 and 31 December 2016. Patient and kidney allograft survival were compared between ABOi, HLAi and ABO/HLA compatible (ABOc/HLAc) groups. RESULTS: Among 711 living donor kidney transplants performed in the UK, 23 were ABOi and 6 were HLAi. Patient survival was 87%, 100% and 96% in ABOi, HLAi and ABOc/HLAc groups, respectively, at median follow-up of 6.8 (3.6-14.0) years post-transplant. Death-censored kidney allograft survival was 100% in all 3 groups at last follow-up. There were no cases of primary non-function in ABOi or HLAi groups, but 2% in the ABOc/HLAc group. There was one reported case of Epstein-Barr viral-induced post-transplant lymphoproliferative disorder. CONCLUSION: Longer term follow-up has shown that ABOi and HLAi kidney transplantation are feasible for pKTR where no compatible donors are available, and that minimising desensitisation should be achieved where possible. A higher resolution version of the Graphical abstract is available as Supplementary information.

Nutritional and Anthropometric Indices in Children Receiving Haemodiafiltration vs Conventional Haemodialysis - The HDF, Heart and Height (3H) Study.

BACKGROUND: The "HDF-Heart-Height" study showed that haemodiafiltration (HDF) is associated with improved growth compared to conventional haemodialysis (HD). We report a post-hoc analysis of this study assessing the effect of extracorporeal dialysis therapies on nutritional indices. METHODS: 107 children were included in the baseline cross-sectional analysis, of whom 79 (43 HD, 36 HDF) completed the 12-month follow-up. Height (Ht), optimal 'dry' weight (Wt), and body mass index (BMI) standard deviations scores (SDS), waist-to-hip ratio, des-acyl ghrelin (DAG), adiponectin, leptin, insulin-like growth factor-1 (IGF-1)-SDS and insulin were measured. RESULTS: The levels of nutritional indices were comparable between HDF and HD patients at baseline and 12-month. On univariable analyses Wt-SDS positively correlated with leptin and IGF-1-SDS, and negatively with DAG, while Ht-SDS of the overall cohort positively correlated with IGF1-SDS and inversely with DAG and adiponectin. On multivariable analyses, higher 12-month Ht-SDS was inversely associated with baseline DAG (beta = -0.13 per 500 higher; 95%CI -0.22, -0.04; P = .004). Higher Wt-SDS at 12-month was positively associated with HDF modality (beta = 0.47 vs HD; 95%CI 0.12-0.83; P = .01) and inversely with baseline DAG (beta = -0.18 per 500 higher; 95%CI -0.32, -0.05; P = .006). Growth Hormone (GH) treated patients receiving HDF had higher annualized increase in Ht SDS compared to those on HD. CONCLUSIONS: In children on HD and HDF both Wt- and Ht-SDS independently correlated with lower baseline levels of the anorexygenic hormone DAG. HDF may attenuate the resistance to GH, but further studies are required to examine the mechanisms linking HDF to improved growth.

Emulation of the control cohort of a randomized controlled trial in pediatric kidney transplantation with Real-World Data from the CERTAIN Registry.

BACKGROUND: Randomized controlled trials in pediatric kidney transplantation are hampered by low incidence and prevalence of kidney failure in children. Real-World Data from patient registries could facilitate the conduct of clinical trials by substituting a control cohort. However, the emulation of a control cohort by registry data in pediatric kidney transplantation has not been investigated so far. METHODS: In this multicenter comparative analysis, we emulated the control cohort (n = 54) of an RCT in pediatric kidney transplant patients (CRADLE trial; ClinicalTrials.gov NCT01544491) with data derived from the Cooperative European Paediatric Renal Transplant Initiative (CERTAIN) registry, using the same inclusion and exclusion criteria (CERTAIN cohort, n = 554). RESULTS: Most baseline patient and transplant characteristics were well comparable between both cohorts. At year 1 posttransplant, a composite efficacy failure end point comprising biopsy-proven acute rejection, graft loss or death (5.8% ± 3.3% vs. 7.5% ± 1.1%, P = 0.33), and kidney function (72.5 ± 24.9 vs. 77.3 ± 24.2 mL/min/1.73 m2 P = 0.19) did not differ significantly between CRADLE and CERTAIN. Furthermore, the incidence and severity of BPAR (5.6% vs. 7.8%), the degree of proteinuria (20.2 ± 13.9 vs. 30.6 ± 58.4 g/mol, P = 0.15), and the key safety parameters such as occurrence of urinary tract infections (24.1% vs. 15.5%, P = 0.10) were well comparable. CONCLUSIONS: In conclusion, usage of Real-World Data from patient registries such as CERTAIN to emulate the control cohort of an RCT is feasible and could facilitate the conduct of clinical trials in pediatric kidney transplantation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Perioperative fluid management and associated complications in children receiving kidney transplants in the UK.

BACKGROUND: Intravenous fluid administration is an essential part of perioperative care for children receiving a kidney transplant. There is a paucity of evidence to guide optimal perioperative fluid management. This study aimed to identify the volume of perioperative fluids administered across 5 UK paediatric kidney transplant centres and explore associations between fluid volume administered, graft function, and fluid-related adverse events. METHODS: Data were collected from five UK paediatric kidney transplant centres on perioperative fluid volumes administered, and incidence of pulmonary oedema, systemic hypertension, and requirement for intensive care support. Children < 18 years of age who received a kidney-only transplant between 1st January 2020 and 31st December 2021 were included. RESULTS: Complete data from 102 children were analysed. The median total volume of fluid administered in 72 h was 377 ml/kg (IQR 149 ml/kg) with a high degree of variability. A negative relationship between total fluid volume administered and day 7 eGFR was noted (p < 0.001). Association between urine volume post-transplant and day 7 eGFR was also negative (p < 0.001). Adverse events were frequent but no significant difference was found in the fluid volume administered to those who developed an adverse event, vs those who did not. CONCLUSIONS: This study describes a high degree of variability in perioperative fluid volumes administered to children receiving kidney transplants. Both fluid volume and urine output were negatively associated with short-term graft function. These data contrast traditional interpretation of high urine output as a marker of graft health, and highlight the need for prospective clinical trials to optimise perioperative fluid administration for this group. A higher resolution version of the Graphical abstract is available as Supplementary information.

Intensive compared with less intensive blood pressure control to prevent adverse cardiac remodelling in children with chronic kidney disease (HOT-KID): a parallel-group, open-label, multicentre, randomised, controlled trial.

BACKGROUND: Optimal target blood pressure to reduce adverse cardiac remodelling in children with chronic kidney disease is uncertain. We hypothesised that lower blood pressure would reduce adverse cardiac remodelling. METHODS: HOT-KID, a parallel-group, open-label, multicentre, randomised, controlled trial, was done in 14 clinical centres across England and Scotland. We included children aged 2-15 years with stage 1-4 chronic kidney disease-ie, an estimated glomerular filtration rate (eGFR) higher than 15 mL/min per 1·73 m2-and who could be followed up for 2 years. Children on antihypertensive medication were eligible as long as it could be changed to angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) if they were not already receiving these therapies. Participants were randomly assigned (1:1) to standard treatment (auscultatory office systolic blood pressure target between the 50th and 75th percentiles) or intensive treatment (systolic target <40th percentile) by the chief investigator using a rapid, secure, web-based randomisation system. ACE inhibitors or ARBs were used as first-line agents, with the dose titrated every 2-4 weeks to achieve the target blood pressure levels. The primary outcome was mean annual difference in left ventricular mass index (LVMI) by echocardiography measured by a masked observer and was assessed in the intention-to-treat population, defined as all the children who underwent randomisation irrespective of the blood pressure reached. Secondary and safety outcomes were the differences between groups in mean left ventricular relative wall thickness, renal function, and adverse effects and were also assessed in the intention-to-treat population. This trial is registered with ISRCTN, ISRCTN25006406. FINDINGS: Between Oct 30, 2012, and Jan 5, 2017, 64 participants were randomly assigned to the intensive treatment group and 60 to the standard treatment group (median age of participants was 10·0 years [IQR 6·8-12·6], 69 [56%] were male and 107 [86%] were of white ethnicity). Median follow-up was 38·7 months (IQR 28·1-52·2). Blood pressure was lower in the intensive treatment group compared with standard treatment group (mean systolic pressure lower by 4 mm Hg, p=0·0012) but in both groups was close to the 50th percentile. The mean annual reduction in LVMI was similar for intensive and standard treatments (-1·9 g/m2·7 [95% CI -2·4 to -1·3] vs -1·2 g/m2·7 [-1·5 to 0·8], with a treatment effect of -0·7 g/m2·7 [95% CI -1·9 to 2·6] per year; p=0·76) and mean value in both groups at the end of follow-up within the normal range. At baseline, elevated relative wall thickness was more marked than increased LVMI and a reduction in relative wall thickness was greater for the intensive treatment group than for the standard treatment group (-0·010 [95% CI 0·015 to -0·006] vs -0·004 [-0·008 to 0·001], treatment effect -0·020 [95% CI -0·039 to -0·009] per year, p=0·0019). Six (5%) participants reached end-stage kidney disease (ie, an eGFR of <15 mL/min per 1·73 m2; three in each group) during the course of the study. The risk difference between treatment groups was 0·02 (95% CI -0·15 to 0·19, p=0·82) for overall adverse events and 0·07 (-0·05 to 0·19, p=0·25) for serious adverse events. Intensive treatment was not associated with worse renal outcomes or greater adverse effects than standard treatment. INTERPRETATION: These results suggest that cardiac remodelling in children with chronic kidney disease is related to blood pressure control and that a target office systolic blood pressure at the 50th percentile is close to the optimal target for preventing increased left ventricular mass. FUNDING: British Heart Foundation.

Utilizing 3D printing to facilitate surgical in-situ paediatric renal artery aneurysm repair for refractory hypertension.

Renal artery aneurysmal (RAA) disease is a rare, but potentially life-threatening cause of renovascular disease presenting with hypertension. Conventional management involves aneurysmal excision followed by renal auto-transplantation. We present the management of a 13-year-old girl with complex multiple saccular aneurysmal disease of the left renal artery with hilar extension and symptomatic hypertension. We used 3D printing to print a patient-specific model that was not implanted in the patient but was used for surgical planning and discussion with the patient and their family. Endovascular options were precluded due to anatomical complexities. Following multi-disciplinary review and patient-specific 3D printing, she underwent successful in-situ RAA repair with intraoperative cooling, without the need for auto-transplantation. 3D printing enabled appreciation of aneurysmal spatial configuration and dimensions that also helped plan the interposition graft length needed following aneurysmal excision. The models provided informed multidisciplinary communications and proved valuable during the consent process with the family for this high-risk procedure. To our knowledge, this is the first reported case utilizing 3D printing to facilitate in-situ complex repair of RAA with intra-hilar extension for paediatric renovascular disease.

Intrinsic Kidney Pathology in Children and Adolescents Following COVID-19 Vaccination: A Systematic Review.

Global COVID-19 vaccination programs for children and adolescents have been developed with international clinical trial data confirming COVID-19 mRNA vaccine safety and efficacy for the pediatric population. The impact of COVID-19 vaccination in the kidneys is thought to be explained by a complex immune-mediated relationship between the two, although the pathophysiological mechanisms of how COVID-19 vaccination potentially induces kidney pathology are not presently well known. Whilst intrinsic kidney pathologies following COVID-19 vaccination have been reported in adults, such cases are only being recently reported with greater frequency in children and adolescents. Conforming to the PRISMA checklist, we conducted a systematic review of the current literature to provide an overview on the range of intrinsic kidney pathologies that have been reported following COVID-19 vaccination in children and adolescents. All English language research articles published on or before 30 June 2022 reporting new-onset or relapsed intrinsic kidney pathology in children or adolescents (≤18 years) following COVID-19 vaccination were selected for qualitative analysis. Out of 18 cases from the 13 published articles selected, there were 10 cases of IgA nephropathy (1 case of rapidly progressive glomerulonephritis requiring acute hemodialysis), 5 cases of minimal change disease (MCD), 1 case of concurrent MCD/tubulointerstitial nephritis (TIN) and 2 cases of TIN. There is no indication currently to avoid vaccination, unless specific circumstances exist, as the benefits of COVID-19 vaccination far outweigh its risks. Concluding the findings from our systematic review based on preliminary evidence, potential adverse effects to the kidney from COVID-19 vaccination affects a small number of children and adolescents among the many who have been vaccinated. There remains good reason at present to support vaccination of children and adolescents with a greater morbidity status, such as those living with preexisting chronic kidney disease. Close observation of all children and adolescents receiving COVID-19 vaccination is recommended, particularly in those with preceding intrinsic kidney pathology to identify risks of relapsed disease.

Renal outcome and plasma methylmalonic acid levels after isolated or combined liver or kidney transplantation in patients with methylmalonic acidemia: A multicenter analysis.

BACKGROUND: Methylmalonic acidemia (MMAemia) is characterized by accumulation of methylmalonic acid (MMA) in all body tissues. To minimize disease-related complications, isolated kidney (KTx), liver (LTx) or combined liver-kidney transplantation (LKTx) have been suggested. However, the impact of these different transplant strategies on outcome are unclear. METHODS: In this multicenter retrospective observational study, we compared plasma MMA levels and estimated glomerular filtration rate (eGFR) data of 83 patients. Sixty-eight patients (82%) had a mut0-type MMAemia, one patient had a mut--type MMAemia, and seven (7.3%) had an inherited defect in cobalamin metabolism (cblA- or cblB-type MMAemia). Median observation period was 3.7 years (0-15.1 years). RESULTS: Twenty-six (31%) patients underwent KTx, 24 (29%) LTx and 33 (40%) LKTx. Posttransplant, mean plasma MMA concentration significantly decreased in all three cohorts; but at month 12, plasma MMA in KTx (1372 ± 1101 µmol/L) was 7.8-fold higher than in LTx (176 ± 103 µmol/L; P < 0.001) and 6.4-fold higher than in LKTx (215 ± 110 µmol/L; P < 0.001). Comparable data were observed at month 24. At time of transplantation, mean eGFR in KTx was 18.1 ± 24.3 mL/min/1.73 m2, in LTx 99.8 ± 29.9 mL/min/1.73 m2, and in LKTx 31.5 ± 21.2 mL/min/1.73 m2. At month 12 posttransplant, mean eGFR in KTx (62.3 ± 30.3 mL/min/1.73 m2) was 33.4% lower than in LTx (93.5 ± 18.3 mL/min/1.73 m2; P = 0.0053) and 25.4% lower than in LKTx (83.5 ± 26.9 mL/min/1.73 m2; P = 0.0403). CONCLUSIONS: In patients with isolated MMAemia, LTx and LKTx lead to markedly lower plasma MMA levels during the first 2 years posttransplant than KTx and are associated with a better preservation of kidney function. LTx should therefore be part of the transplant strategy in MMAemia.

Triglyceride Glucose (TyG) Index: A surrogate biomarker of insulin resistance.

The predictability of triglyceride glucose index (TyG index) as a biomarker for identification of insulin resistance (IR) is being extensively studied in various ethnic populations. TyG index could be a beneficial tool for identification of IR and populations at high risk for developing diabetes in future. However, more studies are required to standardize optimal cut-off values in different ethnicities and populations. The present review describes existing literature, and identifies merits and demerits of TyG index as a surrogate marker for IR.

Use of normal saline and incidence of dyselectrolytaemia in children following kidney transplantation.

BACKGROUND: The use of hypotonic fluid, such as 0.45% saline, following kidney transplantation (KT) in children is associated with a high incidence of electrolyte imbalance, especially hyponatraemia. This can result in serious adverse events, such as cerebral oedema and seizures. The aim of this study was to investigate the incidence of electrolyte disturbance in children when 0.9% saline was the intravenous fluid used in the first 72 h following KT. METHODS: This is a retrospective, observational study of 50 consecutive KT undertaken between January 2017 and January 2019 at a single centre. RESULTS: The median age at KT was 9.2 years (IQR 4-14) and 16 (32%) were females. Thirty-two (64%) were living related donor (LRD) KT and 22 (44%) were carried out in children < 20 kg. The mean volume of fluid administered intra-operatively, and on Day 1, Day 2 and Day 3, were 73 ml/kg, 124 ml/kg, 97 ml/kg and 86 ml/kg, respectively. Hyponatraemia was noted in 4%, hypernatraemia in 18%, hyperkalaemia in 18%, hyperchloraemia in 68% and low bicarbonate was seen in 88%. Fifteen percent of the children had an episode of hyperglycaemia. None of the children developed symptomatic dyselectrolytaemia. There was delayed graft function (DGF) in 4 (8%) recipients - all deceased donor (DD) KT, including 2 who received donations after circulatory death. CONCLUSIONS: While the use of 0.9% saline is associated with a high incidence of electrolyte disturbances, including hyperkalaemia, it reduces the risk of hyponatraemia. None of the children developed a symptomatic electrolyte abnormality. A higher resolution version of the Graphical abstract is available as Supplementary information.

Surgical management of Encapsulating Peritoneal Sclerosis (EPS) in children: international case series and literature review.

BACKGROUND: Encapsulating Peritoneal Sclerosis (EPS) is a rare phenomenon in paediatric patients with kidney failure treated with peritoneal dialysis (PD). This study highlights clinical challenges in the management of EPS, with particular emphasis on peri-operative considerations and surgical technique. METHODS: Retrospective analysis of all paediatric patients with EPS treated at the Manchester Centre for Transplantation. RESULTS: Four patients were included with a median duration of 78 months on PD. All patients had recurrent peritonitis (> 3 episodes), and all had symptoms within three months of a change of dialysis modality from PD to haemodialysis or transplant. In Manchester, care was delivered by a multi-disciplinary team, including surgeons delivering the adult EPS surgical service with a particular focus on nutritional optimisation, sepsis control, and wound management. The surgery involved laparotomy, lavage, and enterolysis of the small bowel + / - stoma formation, depending on intra-abdominal contamination. Two patients had a formal stoma, which were reversed at three and six months, respectively. Two patients underwent primary closure of the abdomen, whereas two patients had re-look procedures at 48 h with secondary closure. One patient had a post-operative wound infection, which was managed medically. One patient's stoma became detached, leading to an intra-abdominal collection requiring re-laparotomy. The median length of stay was 25 days, and patients were discharged once enteral feeding was established. All patients remained free of recurrence with normal gut function and currently two out of four have functioning transplants. CONCLUSIONS: This series demonstrates 100% survival and parenteral feed independence following EPS surgery. Post-operative morbidity was common; however, with individualised experience-based decision-making and relevant additional interventions, patients made full recoveries. Health and development post-surgery continued, allowing the potential for transplantation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Gitelman-Like Syndrome Caused by Pathogenic Variants in mtDNA.

BACKGROUND: Gitelman syndrome is the most frequent hereditary salt-losing tubulopathy characterized by hypokalemic alkalosis and hypomagnesemia. Gitelman syndrome is caused by biallelic pathogenic variants in SLC12A3, encoding the Na+-Cl- cotransporter (NCC) expressed in the distal convoluted tubule. Pathogenic variants of CLCNKB, HNF1B, FXYD2, or KCNJ10 may result in the same renal phenotype of Gitelman syndrome, as they can lead to reduced NCC activity. For approximately 10 percent of patients with a Gitelman syndrome phenotype, the genotype is unknown. METHODS: We identified mitochondrial DNA (mtDNA) variants in three families with Gitelman-like electrolyte abnormalities, then investigated 156 families for variants in MT-TI and MT-TF, which encode the transfer RNAs for phenylalanine and isoleucine. Mitochondrial respiratory chain function was assessed in patient fibroblasts. Mitochondrial dysfunction was induced in NCC-expressing HEK293 cells to assess the effect on thiazide-sensitive 22Na+ transport. RESULTS: Genetic investigations revealed four mtDNA variants in 13 families: m.591C>T (n=7), m.616T>C (n=1), m.643A>G (n=1) (all in MT-TF), and m.4291T>C (n=4, in MT-TI). Variants were near homoplasmic in affected individuals. All variants were classified as pathogenic, except for m.643A>G, which was classified as a variant of uncertain significance. Importantly, affected members of six families with an MT-TF variant additionally suffered from progressive chronic kidney disease. Dysfunction of oxidative phosphorylation complex IV and reduced maximal mitochondrial respiratory capacity were found in patient fibroblasts. In vitro pharmacological inhibition of complex IV, mimicking the effect of the mtDNA variants, inhibited NCC phosphorylation and NCC-mediated sodium uptake. CONCLUSION: Pathogenic mtDNA variants in MT-TF and MT-TI can cause a Gitelman-like syndrome. Genetic investigation of mtDNA should be considered in patients with unexplained Gitelman syndrome-like tubulopathies.