Vascular access challenges in hemodialysis children.

BACKGROUND: Hemodialysis (HD) success is dependent mainly on vascular access (VA). The aim of this study is to share the experience of Pediatric Nephrology Unit (PNU), Cairo University Children's Hospital (CUCH), with VA-related obstacles in end stage kidney disease (ESKD) HD children. METHODS: This is a retrospective analysis of VA related data of 187 ESKD children received regular HD over 3 year duration (2019-2021). Kaplan-Meier curves were used to present arteriovenous fistula (AVF) and cuffed catheters survivals. RESULTS: Uncuffed central venous catheter (CVC) was the primary VA for HD in up to 97.3% with 2.7% of patients had AVF performed and attained maturation before initiation of regular HD. Fifty-six (29.9%) patients have inserted 120 tunneled CVCs. AVFs & AV grafts (AVF) were performed in 79 (42.2%) and 6 (3.2%) patients respectively. There were 112 uncuffed CVCs implanted beneath the screen in Rt internal jugular vein (IJV) (44%) Lt IJV (17%), right internal mammary vein (2.7%) while Trans hepatic (TH) technique was used to place 39 uncuffed CVCs (34%) in the inferior vena cava (IVC). Catheter-related bacteremia (CRB) was the most frequent complication in uncuffed and cuffed CVCs (2.58 / 100 catheters day and 10.1 /1000 catheter days respectively). AVFs achieved a high success rate (83%) after 757.71 ± 512.3 functioning days. CONCLUSION: Native AVF is the preferred VA for pediatric HD but its creation is limited by the small sized vessels where non-cuffed CVC could be a reasonable relatively long-term alternative. Challenging situations (occluded central veins) could benefit from TH technique of CVC insertion in IVC.

Tei Index and its Relation to Outcome of Critically Ill Children on Continuous Renal Replacement Therapy.

OBJECTIVES: To evaluate echocardiographic parameters, especially the Tei index as a predictor of outcome in critically ill children on continuous renal replacement therapy (CRRT). METHODS: This cohort study included all critically ill patients admitted at the Pediatric intensive care unit (PICU) and underwent CRRT. Functional echocardiography and Pediatric Risk of Mortality Index (PRISM) III were used to evaluate the participants. Both the Tei index and the Vasoactive inotropic score (VIS) were estimated. RESULTS: The study included 35 patients with an age range of 6 mo to 14 y. The Tei indexes, VIS, and PRISM III were reported as predictors of mortality with a sensitivity of 88%, 83%, and 94% and a specificity of 73%, 79%, and 89% respectively. In survivors, the mean Tei index score, median VIS, and mean PRISM values were 0.44 ± 0.1, 3.8 (0-40), and 12.06 ± 3.35, respectively. However, in non-survivors, the mean Tei index, median VIS, and mean PRISM score were 0.59 ± 0.16, 0.60 (0-342.5), and 22.94 ± 8.93, respectively. CONCLUSIONS: The Tei index could be used as a predictor for poor outcomes in children receiving CRRT. It is correlated to the PRISM score and VIS.

Covid-19 in Egyptian hemodialysis and kidney transplant children: retrospective analysis of single center experience.

BACKGROUND: Chronic kidney disease stage 5 (CKD 5) populations have peculiar risk for severe Covid-19 infection. Moreover; pediatric data are sparse and lacking. The aim of this study is to report our experience in CKD 5 children treated by hemodialysis (CKD 5D) and CKD 5 children after kidney transplantation (KTR) during one year of Covid-19 pandemic. METHODS: Retrospective analysis of 57 CKD 5 children with Covid-19 like symptoms during 1 year pandemic was performed. A cohort of 19 confirmed patients (13 CKD 5D and 6 KTR) was analyzed in details as regard clinical, laboratory, radiological criteria, management and their short term outcome. RESULTS: CONCLUSION: Pediatric patients on regular HD (CKD 5D) are at higher risk and worse outcome of Covid-19 infection than KT recipients (KTR). Pre-existing HTN and shorter duration after KT are potential risk factors. Reversible AGD after KT and CVC related infections in HD patients are additional presenting features of Covid-19 infection.

Next-generation sequencing in identification of pathogenic variants in primary hyperoxaluria among 21 Egyptian families: Identification of two novel AGXT gene mutations.

BACKGROUND: Primary hyperoxaluria (PH) is a rare heterogeneous, autosomal recessive disorder of glyoxylate metabolism. It is characterized by excessive hepatic production of oxalate resulting in a wide spectrum of clinical, imaging, and functional presentation. The characteristic features of PH comprise of recurrent urolithiasis, renal stones, and/or nephrocalcinosis. Three known types of PH have been identified PH1, PH2, and PH3. Pathogenic variants in AGXT, GRHPR, and HOGA1 cause the phenotypic expression of PH. METHODS: In this study, we describe the clinical and genetic findings of 22 patients from 21 unrelated Egyptian families with the distinctive clinical features of PH. A thorough clinical evaluation followed by an NGS custom panel of AGXT, GRHPR, and HOGA1 genes was done. RESULTS: Two novel mutations (p.Gly27Glu and p.Gln256Serfs*17) and six previously reported mutations (p.Lys12Glnfs*156, p.Lys12Argfs*34, p.Ile244Thr, p.Asn22Ser, p.Pro11Leu, and p.Ile340Met) were identified in AGXT gene. The NGS panel results were validated thereafter using Sanger sequencing. CONCLUSION: Our results extend the number of AGXT mutations identified so far and emphasize the important role of genetic testing in providing proper counseling and patients management.

Primary hyperoxaluria type 1 in children: Clinical classification, renal replacement therapy, and outcome in a single centre experience.

Primary hyperoxaluria type 1 (PH1) is a rare disease that is challenged by the overproduced oxalate and commonly presented with radiopaque renal stones or obstructive uropathy. This study aimed to report clinical presentations, renal replacement therapy (RRT), and outcome of PH1 in end stage kidney disease (ESKD) children. This is an observational cohort study. Data of 22 patients with ESKD due to PH1 were analyzed at Pediatric Nephrology Unit, Faculty of Medicine Cairo University. Infantile onset patients (n = 10) had worst renal outcome (80% with ESRD at presentation, p = 0.019) and worse patient outcome (mortality 40%, p = 0.016) than juvenile (n = 9) and late onset (PH1 n = 3) patients. RRT modalities include peritoneal dialysis (PD) in 7 (31.8%), hemodialysis (HD) in 11 (50%), and combined liver kidney transplantation (CLKT) in 4 (18.2%) patients. Infectious complications were encountered in 42.8% of PD patients. Better HD adequacy was observed with frequent HD (n = 6) and/or HD via arteriovenous fistula (AVF) than with infrequent dialysis (n = 5) and/or via central venous line (CVL) (p = 0.0001 and 0.0047, respectively). Morbidity and mortality (infection related) rates of the whole cohort were 63.6% and 31.8%, respectively. Clinical presentation of PH1 varies according to the age of onset (infantile onset being the most aggressive form). Aggressive HD (better through AVF) is needed to achieve acceptable HD adequacy, PD was challenged by infection. Infection found to be the main cause of mortality even after successful CLKT.

Hearing assessment in Egyptian children with chronic renal failure on regular hemodialysis and renal transplantation children.

INTRODUCTION: Hearing impairment is frequent in patients with end-stage renal disease (ESRD). We aimed to assess the prevalence of hearing impairment in children on regular hemodialysis and renal transplantation. MATERIALS AND METHODS: Transient-evoked otoacoustic emissions (TEOAEs) has been done for 80 children on regular hemodialysis and 40 with renal transplant. RESULTS: In hemodialysis group, TEOAEs showed that 53.8% children had hearing affection, it was significantly related to dialysis duration, dialysis adequacy, vascular access infection, hepatitis C virus (HCV) infection, and ototoxic drugs (p = 0.001, 0.037, 0.011, 0.004, 0.030, 0.007, and 0.044, respectively). In renal transplant group hearing impairment was 25%. There was significant relation with period of dialysis before transplantation and biopsy proved rejection (p = 0.008, <0.001, respectively). CONCLUSION: Hearing impairment is a common finding in ESRD patients. Thus audiological assessment must be done in these patients.

Pediatric focal segmental glomerulosclerosis: favorable transplantation outcome with plasma exchange.

BACKGROUND: Although kidney transplantation (KTX) is the treatment of choice for pediatric end stage kidney disease (ESKD); concerns for recurrence in cases of focal segmental glomerulosclerosis (FSGS) are still present. This study aimed to investigate the outcome of KTX in children with ESKD secondary to FSGS, with implementation of preemptive perioperative plasma exchange (PE) for non-genetically proven patients. METHODS: Forty FSGS pediatric kidney transplant recipients were studied. Of them: 12 patients (30%) had genetically proven NPHS2 mutations/familial and 28 (70%) were sporadic FSGS patients. All sporadic patients electively received 6 perioperative PE sessions. Patients with recurrence of proteinuria (n = 13; including 3 patients with genetic/familial and 10 patients with sporadic FSGS) were managed with PE and Rituximab (RTX). Kaplan-Meier curves were used to analyze graft and recurrence free survival data. RESULTS: The mean follow-up duration after KTX was 3.8 ± 2.86 years. Recurrence of proteinuria was encountered early postoperative in 11 patients (27.5%) and late (1.6 and 2.9 years after KTX) in 2 patients (5%). All patients with early recurrence achieved complete remission, while patients with late recurrence developed graft failure. Current serum creatinine and proteinuria levels were not different in patients received PE (n = 31) and patients did not PE (n = 9) (p = 0.308 and 0.287 respectively). Current serum creatinine and proteinuria levels in sporadic patients (n = 28) after prophylactic perioperative PE were not different from those of genetic/ familial patients (n = 12) (p = 0.303 and 0.144 respectively). Proteinuria was less in patients underwent native nephrectomy than others immediately postoperative and at assessment (p = 0.002 & 0.0031 respectively). One-year graft and patient survival was 93.8% with a mean 1-year serum creatinine of 0.67 ± 0.25 mg/dl. Three graft losses (7.5%) were due to chronic rejection 3.3, 3.75 and 4.17 years after KTX and 2 patients' mortality (5%) occurred early postoperative (first 2 weeks). CONCLUSION: FSGS transplanted children have favorable outcomes with perioperative PE for non-genetically proven cases. Early recurrence after KTX can be successfully managed with PE and RTX.

Native vs. active vitamin D in children with chronic kidney disease: a cross-over study.

BACKGROUND: The rationale for the prescription of vitamin D analogues in patients with chronic kidney disease (CKD) is still a matter of debate. We aimed to compare native vs. active forms of vitamin D on pre-dialysis children with CKD and evaluate effects on calcium (Ca), phosphorus (P), and parathyroid hormone (PTH). METHODS: Thirty children with pre-dialysis CKD were enrolled in a prospective cross-over study. Patients were randomly classified into two groups. Group A received native cholecalciferol while group B received alfacalcidol for 3 months. After 1 month (washout period), patients were switched to receive the opposite form for another 3 months. Serum Ca, P, alkaline phosphatase (ALP), PTH, and 25(OH)D3 were measured at study start (BL-1), end of first period (FU-1), before second period (BL-2), and after second period (FU-2). RESULTS: There was significant increase in levels of 25(OH)D3 after administration of either native or active vitamin D in the first period in both groups (p < 0.001 and < 0.001, respectively) and also in the second period for both groups (p = 0.02 and < 0.001, respectively). There was no significant difference between both groups regarding changes in serum Ca (1st period; p = 0.770 and 2nd period; p = 0.412), serum P (1st period; p = 0.835, 2nd period; p = 0.052), and serum PTH (1st period; p = 0.250, 2nd period; p = 0.539). CONCLUSION: Alfacalcidol and native vitamin D3 were equally effective in decreasing PTH levels and increasing serum 25(OH)D3 in pre-dialysis CKD patients. There was no significant difference between the two forms regarding changes in serum Ca or P. Graphical abstract.

Genetic polymorphisms in CLDN14 (rs219780) and ALP (rs1256328) genes are associated with risk of nephrolithiasis in Egyptian children.

OBJECTIVE: Nephrolithiasis results from metabolic and anatomic abnormalities together with genetic factors. Claudin 14 (CLDN14) is a protein that regulates the passage of small solutes through the kidneys. Alkaline phosphatase (ALPL) hydrolyzes the pyrophosphate to free phosphate, proposing its enabling role in nephrolithiasis development. Solute carrier family 13 member 2 (SLC13A2) encodes Na+-Pi cotransporter 2a, which is responsible for the renal absorption of phosphate. We aimed to detect the association between CLDN14, ALPL, and SLC13A2 genetic variants and susceptibility to nephrolithiasis in the Egyptian pediatric population. MATERIAL AND METHODS: We enrolled 204 consecutive pediatric patients with nephrolithiasis, and 126 normal individuals served as controls. Real-time polymerase chain reaction analysis of CLDN14 rs219780, ALPL rs1256328, and SLC34A1 rs11746443 single-nucleotide polymorphisms (SNPs) was performed. RESULTS: We found that individuals carrying the T allele of CLDN14 rs219780 and ALPL rs1256328 SNPs had a significantly higher risk of nephrolithiasis than the controls (p=0.001 and 0.001, respectively). Genetic association analyses identified that CLDN14 rs219780 and ALPL rs1256328SNPs were significantly associated with the nephrolithiasis status (odds ratio [OR] =4.51; 95% confidence interval [CI]=2.758-7.374; p=0.001 and OR=6.088; 95% CI=3.651-10.152; p=0.001, respectively). The sequence variant ALPL rs1256328 T allele had a significant correlation with the increased serum alkaline phosphatase levels in children with nephrolithiasis (p=0.02). No significant association was found between SLC34A1 rs11746443 SNP and the risk of nephrolithiasis (p=0.5). CONCLUSION: CLDN14 rs219780 and ALPL rs1256328 SNPs might raise the risk of nephrolithiasis in Egyptian children, and might be used as genetic markers in these patients.

Does renal transplant in children with LUTD improve their bladder function?

Much is still unknown about LUT function after receiving renal graft. Graft function was the main focus of different studies discussing the same issue. However, these studies ignored the effects of the graft on lower tract function and more demand for bladder cycling and growth of the child. Therefore, we aimed at evaluating the LUT function after RT into patients with LUTD. We enrolled a retrospective cohort of 83 live renal transplant children with LUTD. The 44 patients in Group (A) had a defunctionalized bladder, and the 39 patients in Group (B) had underlying LUT pathology. All patients had clinical and urodynamic evaluation of LUT functions at least 1 year after RT. We found that the improvement in patients with impaired bladder compliance was 73% in Group (A) and 60% in Group (B), with no statistically significant difference between the study groups. In Group (B), there was statistically significant worsening of MFP (8.4%) and mean PVR (79.9%) after RT. In Group (A), mild but stable significant improvement of all clinical and urodynamic parameters was observed. Serum creatinine was significantly worse in patients with pathological LUTD compared with those with defunctionalized bladder but without significant effect on graft survival. All LUT variables seemed to have no adverse effect on graft survival except for use of CIC and augmented bladder. Incident UTI independent of LUT variables accounted for 20% of graft creatinine change.

Pediatric kidney transplantation in Egypt: Results of 10-year single-center experience.

Pediatric kidney transplantation is a multidisciplinary therapy that needs special consideration and experience. In this study, we aimed to present CUCH experience; over a 10-year period, as a specialized center of kidney transplantation in children. We studied 148 transplantations performed at a single center from 2009 to 2018. Pretransplant and follow-up data were collected and graft/patient survival rates were evaluated. A total of 48 patients developed at least one rejection episode during 688 patient-years of follow-up. Infections, recurrence of original disease, and malignancy were the most important encountered medical complications (20%, 2%, and 1.4%, respectively). One-year patient survival was 94.1%, while graft and patient survival was 91.9%. Graft/patient survival at 5, 7, and 9 years was 90%, 77%, and 58%, respectively. Infections were the main cause (69%) of mortality. Death with a functioning graft and CR were the main causes of graft loss (48% and 33%, respectively). Pediatric kidney transplantation in Egypt is still a challenging yet successful experience. Rejections and infections are the most frequent complications. Short-term outcomes surpass long-term ones and graft survival rates are similar to the international standard.

Left ventricular mass index and subendocardial myocardial function in children with chronic kidney disease, a transmural strain and three-dimensional echocardiographic study.

Introduction: Left ventricular hypertrophy (LVH) is the commonest myocardial response to chronic kidney disease (CKD); this response has been regarded detrimental as it impairs the blood flow to the deepest layers of the myocardium causing progressive myocardial dysfunction. The aim of these series is to assess the determinants of LVH in CKD patients and its impact on subendocardial function in such patients. Methods: This study has been conducted on 40 CKD patients (Group 1) and 40 age-matched controls, both groups were assessed by transmural echocardiography to determine the subepicardial and subendocardial global longitudinal strain (GLS) as an expression of the systolic function of each of those layers. LVH was assessed by calculation of left ventricle mass index (LVMI). Both groups underwent ambulatory blood pressure monitoring. Group 1 was assessed as regards lipid profile and insulin resistance by homeostasis model assessment of insulin resistance (HOMA-IR). Results: HOMA-IR proved to be a more important determinant of LV hypertrophy than SBP and DBP with a P of 0.01. Moreover subendocardial GLS was negatively correlated with LVMI with r = 0.69 and P < 0.01 denoting the negative effect. LVH plays on subendocardial function probably by impairing myocardial perfusion. Conclusion: This study points toward the importance of insulin resistance in aggravation of myocardial remodeling in CKD patients; more studies are warranted to examine the role of insulin Sensitizers in reversing such remodeling and restoring subendocardial function in such important systemic disorder.

Assessment of Quality of Life among Children with End-Stage Renal Disease: A Cross-Sectional Study.

Background: Measuring health-related quality of life is considered an important outcome indicator in evaluating health-care interventions and treatments and in understanding the burden of diseases. Objectives: This study aimed at assessing quality of life among children with end-stage renal disease, either undergoing hemodialysis or had renal transplantation therapy and comparing it with healthy controls. Methods: A cross-sectional study was conducted between December 2016 and May 2017 in Abo El-Reesh Pediatric Hospital using parent/child reports of generic module for QoL assessment: PedsQLTM Inventory version 4 for both cases and controls. Disease-specific module: PedsQLTM ESRD version 3 was used for ESRD cases. 55 ESRD cases and 86 controls were enrolled in the study. Results: Statistically significant difference between ESRD cases and controls regarding all aspects of QoL was found; total QoL mean score was 58.4 ± 15.3 and 86.8 ± 10 among cases and controls, respectively. All individual QoL domains were significantly worse in ESRD cases. Transplantation group had better Spearman's correlation between child and parents' scores which showed significant positive moderate correlation. Conclusions: ESRD and its treatment modalities are affecting negatively all aspects of quality of life; incorporating QoL assessment and management is highly recommended.

Serum Soluble Interleukin 2 Receptor Level as a Marker of Acute Rejection in Pediatric Kidney Transplant Recipients.

BACKGROUND: Despite advances in immunosuppression, acute allograft rejection remains one of the key factors affecting patient and graft survival in pediatric kidney transplantation. The aim of the study is to evaluate the role of serum soluble IL2 receptor (sIL2R) level as a noninvasive assessment parameter of acute rejection (AR). METHOD: Serum sIL2R level was measured (using enzyme-linked immune-sorbent assay technique) in 60 pediatric kidney transplant recipients (30 recipients with AR and 30 transplant recipients with stable graft function). RESULTS: The mean values of sIL2R level in patients experiencing AR (14.8 ± 6.54) ng/mL were significantly higher than that in patients with stable graft functions (6.44 ±1.95) ng/mL (p = 0.0001). In addition; patients with AR proved by graft biopsy had their mean values of sIL2R level (16.19 ± 7.48) ng/mL significantly higher than that of other recipients in the study population (p = 0.032). CONCLUSION: Serum sIL2R level may serve as a noninvasive diagnostic indicator in pediatric kidney transplant recipients experiencing AR.

Klotho G-395A gene polymorphism: impact on progression of end-stage renal disease and development of cardiovascular complications in children on dialysis.

BACKGROUND: Klotho G-395-A gene polymorphism may impact children with end-stage renal disease (ESRD). We investigated the relevance of Klotho G-395-A on ESRD development and progression, and its relationship with evolution of cardiovascular complications in pediatric dialysis patients. METHODS: Fifty-five children with chronic kidney disease (CKD) and seventy healthy children were genotyped for Klotho G-395A. RESULTS: Incidence of GA/AA genotypes and A allele were higher in ESRD patients compared with controls (54.5 vs. 7.1%, P < 0.001; 30.9 vs. 13.6%, P = 0.001, respectively). Also, children with GA/AA genotypes were 15.6 times more likely to develop ESRD than with GG genotype (95% CI 5.4-44.7, P < 0.001). A allele carriers have 2.8 times higher risk of developing ESRD than those with G allele (95% CI 1.5-5.35, P = 0.001). Also, the A allele could be considered a predictor of cardiovascular disease (CVD), as carriers have 161 times higher risk of cardiovascular complications than non-carriers (95% CI 21-1233, P < 0.001). All ESRD patients with CVD presented with left ventricular hypertrophy (LVH) and the frequency of A allele was significantly higher among ESRD children with LVH, whereas G allele frequency was significantly higher among ESRD children without LVH. CONCLUSIONS: The A allele of the G-395A Klotho gene polymorphism shows a significantly higher frequency among children with CKD and those with CVD and LVH. This mutant allele could be used as a risk marker for the development of ESRD as well as a predictor of CVD in these children.

Outcome of pediatric renal transplantation in urological versus non-urological causes of end stage renal disease: Does it matter?

INTRODUCTION: Causes for end stage renal disease (ESRD) in children can be categorized into urological causes or non-urological causes. We sought to compare the outcomes of urological and non-urological causes of ESRD in children. METHODS: Patients were divided into two groups: urological causes of ESRD versus non-urological causes of ESRD. All patients and donors had at least 6 months of follow-up. The main outcomes included the effect on complications and renal function. Comparisons were carried out using the chi-square test or the Student t-test. Multivariate logistic regression analysis was used to define the effect of different variables on the outcome of renal transplantation (Table). RESULTS: Our study included 123 patients, 91 males. The mean age was 9 years and mean follow up was 46 months. Two-thirds of the patients had non-urological causes of ESRD. Overall survival was 100%, and only one patient needed a graft nephrectomy 3 months after the transplant. The mean estimated glomerular filtration rate was 117 mL/min, and did not differ significantly between the two groups (p = 0.13). Multivariable regression showed that female gender (OR 8.7, 95% CI 2.9-26, p = 0 0.0001) was associated with better renal function, while having a urological cause of ESRD (OR 0.28, CI 0.08-0.98, p = 0 0.05) was associated with worse renal function. Non-urological causes of ESRD were significantly less likely to develop complications following renal transplantation (OR 0.28, CI 0.09-0.89, p = 0 0.03). CONCLUSION: Female patients with non-urological causes of ESRD are more likely to have better long-term renal functions, and less liable to develop complications following renal transplant.

Risk factors for urological complications following living donor renal transplantation in children.

The aim of this study was to detect possible risk factors for UC and UTI following pediatric renal Tx and effect of these complications on outcome. One hundred and eight children who underwent living donor Tx between 2009 and 2015 were retrospectively included. Extraperitoneal approach was used with stented tunneled extravesical procedure. Mean recipient age was 9.89 ± 3.46 years while mean weight was 25.22 ± 10.43 kg. Seventy-three (67.6%) recipients were boys while 92 (85.2%) were related to donors. Urological causes of ESRD were present in 33 (30.6%) recipients (14 [13%] posterior urethral valve, 16 [14.8%] VUR, and 3 [2.8%] neurogenic bladder). Augmentation ileocystoplasty was performed in 9 (8.3%) patients. Mean follow-up was 39.3 ± 17.33 months. UC were detected in 10 (9.3%) children (leakage 4 [3.7%], obstruction 3 [2.8%], and VUR 3 [2.8%]) while UTIs were reported in 40 (37%) children. After logistic regression analysis, UC were significantly higher in children with cystoplasty (44.4% vs 6.1%; P = .001). UTIs were significantly higher in girls (51.4% vs 30.1%; P = .001) and in children with urological causes of ESRD (51.5% vs 30.7%; P = .049). UC and UTI were not significantly associated with increased graft loss or mortality. UC were significantly higher in children with cystoplasty while UTIs were significantly higher in girls and children with urological causes of ESRD. Presence of UC did not affect the rate of graft loss or mortality due to its early detection and proper management.

Visfatin versus Flow-Mediated Dilatation as a Marker of Endothelial Dysfunction in Pediatric Renal Transplant Recipients.

BACKGROUND: Renal transplantation (RTx) is the treatment of choice for paediatric end-stage renal disease (ESRD). A major cause of morbidity and mortality after RTx is cardiovascular disease. Independent predictors of cardiovascular events were shown to constitute an endothelial dysfunction (ED). This study aims to evaluate Visfatin serum level in comparison to brachial artery flow-mediated dilatation (FMD) as a marker of endothelial dysfunction in paediatric RTx recipients. METHODS: Visfatin serum level has been evaluated in 30 patients on regular hemodialysis (HD), 36 patients post-RTx and 30 controls as a measure for ED, and has been compared to brachial artery FMD. RESULTS: Visfatin level in transplant recipients was significantly lower than the hemodialysis group as well as FMD was better in transplant recipients. In spite of marked improvement of FMD and marked reduction of visfatin in post-RTx no direct statistical correlation was found between serum Visfatin level and flow-mediated dilatation. CONCLUSION: Pediatric RTx recipients show lower serum Visfatin level and better FMD than those on regular hemodialysis, reflecting less endothelial dysfunction (ED) and less cardiovascular risk. FMD in kidney transplant recipients tends to be less than normal subjects while visfatin level of the same group is similar to controls. Pediatric RTx appears to have a positive impact on the growth development of children with ESRD.

Levels of cystatin C in low- and high-flux hemodialysis in children with end-stage renal disease.

BACKGROUND: Cystatin-C (CyC) is a middle molecule that is freely filtered at the glomerulus and almost completely reabsorbed by the proximal tubules. The aim of this study was to evaluate serum CyC and its reduction ratio as a biomarker for assessing the adequacy of the hemodialysis (HD) sessions in children with end-stage renal disease on maintenance HD. We also compared levels of CyC in patients on low-flux HD (LFH) and high-flux HD (HFH). METHODS: Forty patients were included in the study and divided into two groups, with one group (16 patients) receiving HFH and the other group receiving LFH (24 patients) (high-flux and low-flux polysulfone filters, respectively). Before and after each dialysis session serum CyC and beta-2-microglobulin (B2M) levels were measured using an ELISA technique, and routine laboratory tests were performed for each patient. RESULTS: Pre-dialytic levels of CyC were significantly lower in the patients receiving HFH than in those receiving LFH (7.33 ± 1.35 vs. 9.73 ± 0.93, respectively; p < 0.0001). In the HFH group, post-dialytic levels of serum CyC were significantly lower than pre-dialytic levels (4.49 ± 0.71 vs. 7.33 ± 1.35, respectively; p < 0.0001). The reduction ratio (RR) of CyC was significantly higher in the HFH group than in the LFH group (38.2 ± 3.91 vs. -6.49 ± 5.05, respectively; p < 0.0001). Serum CyC level significantly correlated with B2M, urea and creatinine levels in both the LFH and HFH groups, whereas its RR significantly correlated with the RRs of urea, creatinine, and B2M in the HFH group. CONCLUSION: The results of our study emphasize the role of CyC as a good marker for assessing the adequacy of HD sessions in children on HFH and show that the CyC RR may be used as an index of middle-molecule toxin clearance following HFH sessions.

FcγRIIa defunctioning polymorphism in paediatric patients with renal allograft.

INTRODUCTION: Fc gamma receptor (FcγR) IIa is considered the most widely distributed of the three classes of Fc receptors, and it expresses an allelic polymorphism. This type of polymorphism may modify the immune response and may be an important factor for some diseases. The aim of the study reported herein was to evaluate the association between the FcγRIIa polymorphism and susceptibility to both end-stage renal disease (ESRD) and acute kidney graft rejection (AR) in children who have undergone renal transplantation. MATERIAL AND METHODS: The study evaluated 70 children who had undergone transplantation and 60 healthy subjects. AR was observed in 25 children. RESULTS: FcγRIIa genotypes and alleles were significantly different between transplantation patients and the control group. The assessment for FcγR of the groups in which AR was present showed that there was only a risk of having an acute rejection in homozygous genotype RR. CONCLUSIONS: FcγRIIa RR genotype and allele frequency was increased in paediatric renal transplant recipients. The present findings showed that FcγRIIa genotype may be related to ESRD disease susceptibility, and FcγRIIa polymorphisms seemed to affect AR.