Enrico Vidal

Peritoneal dialysis in infants: the experience of the Italian Registry of Paediatric Chronic Dialysis

BACKGROUND Although chronic peritoneal dialysis (CPD) is considered the replacement therapy of choice for infants with end-stage renal failure, many questions persist about treatment risks and outcomes. METHODS We present data on 84 infants who started CPD at <1 year of age; these patients represent 12% of the total population of the Italian Registry of Paediatric Chronic Dialysis. We analysed patient records from all children consecutively treated with CPD between 1995 and 2007 in Italy. Growth data analysis was performed only in infants with complete auxological parameters at 0, 6 and 12 months of follow-up. RESULTS Median age at the start of CPD was 6.9 months, weight was 6.1 kg and length 63.6 cm. In one-half of the study population diagnosis leading to renal failure was congenital nephrouropathy. Twenty-eight per cent of the children had at least one pre-existing comorbidity. The mean height standard deviation score was -1.65 at the start of CPD, -1.82 after 12 months and -1.53 after 24 months. Catch-up growth was documented in 50% of patients during dialysis. A positive correlation was observed between longitudinal growth and both exchange volume (R(2) = 0.36) and dialysis session length (R(2) = 0.35), while a negative association was found with the number of peritonitis cases (P = 0.003). Peritonitis incidence was 1:20.7 episode:CPD-months (1:28.3 in the older children from the same registry) and was significantly higher in children with oligoanuria (1:15.5 episode:CPD-months) compared to infants with residual renal function (1:37.4 episode:CPD-months). Catheter survival rate was 70% at 12 months and 51% at 24 months. Catheter-related complications were similar in infants and older children (1:20.5 versus 1:19.8 episode:CPD-months), while clinical complications were more frequent in children under 1 year of age (1:18.3 versus 1:25.2 episode:CPD-months; P < 0.05). During the follow-up period, 33 patients were transplanted (39.3%), 18 were shifted to haemodialysis (21.4%) and 8 died (9.5%). The mortality rate was 4-fold greater than in older children (2.3%). CONCLUSIONS Our data confirm that infants on CPD represent a high-risk group; however, our experience demonstrated that growth was acceptable and a large portion was successfully transplanted. Increased efforts should be aimed at optimizing dialysis efficiency and preventing peritonitis. The higher mortality rate in infants was largely caused by comorbidities.

Impact of global economic disparities on practices and outcomes of chronic peritoneal dialysis in children: insights from the International Pediatric Peritoneal Dialysis Network Registry

♦ Background, Objectives, and Methods: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross national income (GNI), to identify the impact of economic conditions on CPD practices and outcomes in children and adolescents. ♦ Results: We observed close associations of GNI with the fraction of very young patients on dialysis, the presence and number of comorbidities, the prevalence of patients with unexplained causes of end-stage kidney disease, and the rate of culture-negative peritonitis. The prevalence of automated PD increased with GNI, but was 46% even in the lowest GNI stratum. The GNI stratum also affected the use of biocompatible peritoneal dialysis fluids, enteral tube feeding, calcium-free phosphate binders, active vitamin D analogs, and erythropoiesis-stimulating agents (ESAs). Patient mortality was strongly affected by GNI (hazard ratio per

Duplex system ureterocele in infants: Should we reconsider the indications for secondary surgery after endoscopic puncture or partial nephrectomy?

10 000: 3.3; 95% confidence interval: 2.0 to 5.5) independently of young patient age and the number of comorbidities present. Patients from low-income countries tended to die more often from infections unrelated to CPD (5 of 9 vs 15 of 61, p = 0.1). The GNI was also a strong independent predictor of standardized height (p < 0.0001), adding to the impact of congenital renal disease, anuria, age at PD start, and dialysis vintage. Patients from the lower economic strata (GNI <

Plasmapheresis-resistant acute humoral rejection successfully treated with anti-C5 antibody

18 000) had higher serum parathyroid hormone (PTH) and lower serum calcium, and achieved lower hemoglobin concentrations. No impact of GNI was observed with regard to CPD technique survival or peritonitis incidence. ♦ Conclusions: We conclude that CPD is practiced successfully, albeit with major regional variation related to economic differences, in children around the globe. The variations encompass the acceptance of very young patients and those with associated comorbidities to chronic dialysis programs, the use of automated PD and expensive drugs, and the diagnostic management of peritonitis. These variations in practice related to economic difference do not appear to affect PD technique survival; however, economic conditions seem to affect mortality on dialysis and standardized height, a marker of global child morbidity.

Markers of bone metabolism are affected by renal function and growth hormone therapy in children with chronic kidney disease.

OBJECTIVE We assessed outcomes and need for secondary surgery after primary trans-urethral puncture (TUP) or upper pole partial nephrectomy (UPPN) in duplex system ureterocele (DSU) patients undergoing management that disregards vesicoureteral reflux and upper pole function. SUBJECTS AND METHODS Between 2003 and 2010, 41 DSU <1 year underwent TUP (n = 32) or UPPN (n = 9). Postoperatively, additional investigations and surgery were limited to cases showing persistent hydroureteronephrosis or developing recurrent febrile urinary tract infections (UTI). Outcome parameters included upper tract decompression, UTI after decompression, continence status, and secondary surgery rate. Preoperative variables were compared between patients who required secondary surgery and those who did not. RESULTS Additional surgery was required for persistent hydroureteronephrosis in 20% of cases after TUP vs none after UPPN. After decompression, 4 female patients developed recurrent febrile UTI and 2 required additional surgeries. No case suffered from urinary incontinence. After a median (range) follow-up of 46 (17-102) months, TUP or UPPN was the only surgery required in 32 (78%) cases irrespective of preoperative variables. CONCLUSION UPPN seems more effective than TUP in decompressing severely dilated urinary tracts. After decompression, disregarding VUR status and upper pole function, TUP or UPPN is the only procedure required in 80% of DSU cases, regardless of preoperative variables.

Encapsulating peritoneal sclerosis in paediatric peritoneal dialysis patients: the experience of the Italian Registry of Pediatric Chronic Dialysis

Even if kidney graft survival has improved during the last decades, sensitized pediatric patients are an emerging problem. We describe a 17‐yr‐old male who lost his first graft due to chronic rejection becoming hyperimmunized (CDC PRA 99.61%). A desensitization protocol based on high‐dose IVIG, PP, and two Mabthera® infusions was performed with minor response (CDC PRA post‐desensitization 80%). One month after his second non‐living transplant, he developed a biopsy‐proven AMR; post‐transplant immunological monitoring showed the presence of donor‐specific anti‐DQ5 antibodies (DSA, MFI 20.000). He received methylprednisolone pulses and 45 PP sessions without clinical response; eculizumab was then used to salvage a kidney undergoing severe PP‐resistant rejection. A biopsy performed after the fourth eculizumab infusion showed complete resolution of AMR. Eculizumab infusions were then continued for the first year post‐transplantation. Two yr after transplantation, graft function is stable. Anti‐C5 therapy may represent an effective therapeutic option in pediatric patients with PP‐resistant AMR.

Anorectal malformation and associated end-stage renal disease: Management from newborn to adult life

Objectives The extent and relevance of altered bone metabolism for statural growth in children with chronic kidney disease is controversial. We analyzed the impact of renal dysfunction and recombinant growth hormone therapy on a panel of serum markers of bone metabolism in a large pediatric chronic kidney disease cohort. Methods Bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase 5b (TRAP5b), sclerostin and C-terminal FGF-23 (cFGF23) normalized for age and sex were analyzed in 556 children aged 6–18 years with an estimated glomerular filtration rate (eGFR) of 10–60 ml/min/1.73m2. 41 children receiving recombinant growth hormone therapy were compared to an untreated matched control group. Results Standardized levels of BAP, TRAP5b and cFGF-23 were increased whereas sclerostin was reduced. BAP was correlated positively and cFGF-23 inversely with eGFR. Intact serum parathormone was an independent positive predictor of BAP and TRAP5b and negatively associated with sclerostin. BAP and TRAP5B were negatively affected by increased C-reactive protein levels. In children receiving recombinant growth hormone, BAP was higher and TRAP5b lower than in untreated controls. Sclerostin levels were in the normal range and higher than in untreated controls. Serum sclerostin and cFGF-23 independently predicted height standard deviation score, and BAP and TRAP5b the prospective change in height standard deviation score. Conclusion Markers of bone metabolism indicate a high-bone turnover state in children with chronic kidney disease. Growth hormone induces an osteoanabolic pattern and normalizes osteocyte activity. The osteocyte markers cFGF23 and sclerostin are associated with standardized height, and the markers of bone turnover predict height velocity.

Blood pressure measurement in children: which method? which is the gold standard?

BACKGROUND Paediatric literature about encapsulating peritoneal sclerosis (EPS) is limited and comes primarily from anecdotic experiences. In this study, we described the incidence and characteristics of EPS in a large paediatric chronic peritoneal dialysis (CPD) patient population. METHODS We reviewed files of patients starting CPD at <16 years of age, recorded from January 1986 to December 2011 by the Italian Registry of Pediatric Chronic Dialysis (n = 712). Moreover, in December 2011, a survey was performed involving all the Italian Pediatric Nephrology Units to report such EPS cases that occurred after CPD withdrawal. RESULTS Fourteen EPS cases were reported, resulting in a prevalence of 1.9%. The median age of EPS cases was 4.8 years (range 0.6-14.4) at the start of CPD and 14.3 years (6.5-26.8) at EPS diagnosis. Eleven EPS cases received CPD for longer than 5 years. At diagnosis, nine patients were still on CPD, two were on haemodialysis and three were transplanted. In eight patients, the primary renal disease was represented by glomerulopathy, mainly focal segmental glomerulosclerosis (n = 5). In the last 6 months prior to CPD discontinuation, 10 patients were treated with solutions containing more than 2.27% glucose. Peritonitis incidence was 1:26.8 CPD-months, similar to that calculated in children >12 months of age from the same registry (1:28.3 CPD-months). The mortality rate was 43%. A more aggressive course and an association with calcineurin inhibitors were observed in transplanted patients. CONCLUSIONS Surveillance for EPS should be maintained in high-risk children who received long-term PD even after years from CPD withdrawal.

Anterior Ischemic Optical Neuropathy in Children on Chronic Peritoneal Dialysis: Report of 7 Cases

BACKGROUND/OBJECTIVE Renal failure remains one of the most significant causes of morbidity in patients with anorectal malformations (ARM). In the modern era, an increasing number of children born with ARM and genito-urinary (GU) anomalies reach adulthood and require continued multidisciplinary care for the rest of their life. The aim of this study is to present our institutional experience in the management of pediatric chronic renal failure related to severe GU anomalies and anorectal malformations. METHODS AND RESULTS Three hundred twenty-one patients with ARM have been followed at our institution since 1987. Six patients developed end-stage renal disease (ESRD) and received a kidney transplant at different ages. One patient is currently followed for mild, progressive chronic renal failure. These seven cases are reported along with a broad discussion concerning etiology of renal failure, neonatal surgical management, pediatric dialysis, urologic issues, and kidney transplantation. CONCLUSION Complex GU anomalies associated with ARM require a long-term approach by specialized pediatric and adult clinicians to optimize the care of this selected population of patients.

Therapeutic Plasma Exchange in Neonates and Infants: Successful Use of a Miniaturized Machine

The burden of hypertension has become increasingly prevalent in children. Hypertension that begins in childhood can carry on into adulthood, therefore early detection, accurate diagnosis and effective therapy of high blood pressure may improve long-term outcomes of children and adolescents. As far as pediatric hypertension is concerned, doubts still persist about the right instruments, modalities and standards of reference that should be used in routine practice. Due to the dynamic process of growth and development, many physiological parameters undergo intensive change with age. Therefore, in children, the definition of hypertension can not rely on a single blood pressure level but should be based on age- and height-specific percentiles. In this review, we introduce the nephrologist to the correct definition of high blood pressure in children. Moreover, we specifically address the main characteristics of different modalities for blood pressure measurement in children, focusing on practical aspects. The latest international guidelines and appropriate standards of reference for office, ambulatory and home blood pressure data collection are presented. As clinicians are being faced with a greater number of children with hypertension, they should be aware of these peculiarities.