Chronic peritoneal dialysis in Turkish children: a multicenter study

[Etiologies of end-stage renal disease of children in Tunisia]

BACKGROUND

The end-stage renal disease (ESRD) in children has special features in terms of etiologies, therapeutic modalities and access to renal transplantation. In Tunisia, there are no data on the epidemiology of ESRD in children. The aim of our study was to describe epidemiology of ESRD among Tunisian children.

METHODS

This retrospective study was conducted in pediatric departments in Charles-Nicolle Hospital, Tunis and Hedi Chaker hospital, Sfax, during a period of 15 years (1st January 1998-31st December 2013). We included children who develop ESRD before the age of 15 years.

RESULTS

In total, 166 patients were included. The median duration of follow-up was 48 months. We collected respectively 24 children (14.5%) aged less than 2 years, 24 children (14.5%) aged between 2 and 6 years and 118 children (71%) older than 6 years. The sex ratio was equal to 1.4. The mean incidence was 4.25 cases per million children. The main causes were represented by congenital anomalies of the kidneys and urinary tract (35.5%), hereditary renal disease (31.3%) and glomerular kidney disease (9.6%). All patients were treated in kidney transplant dialysis programs; the main mode of dialysis was represented by peritoneal dialysis, which represented the initial dialysis mode in 81% of cases. The transition to hemodialysis was noted in 43.4% cases. Thirty-eight patients (22.8%) were transplanted. The mortality rate was 27.1%. The leading cause of death was cardiovascular diseases (37.7%) and infections (22.2%).

CONCLUSION

The creation of a national registry of kidney disease in Tunisia is necessary for a better knowledge of needs for dialysis and renal transplantation in children.

Factors affecting the success of endoscopic treatment of vesicoureteral reflux and comparison of two dextranomer based bulking agents: does bulking substance matter?

INTRODUCTION

Among the interventional treatment modalities for vesicoureteral reflux (VUR), endoscopic subureteric injection seems to be the least invasive method with acceptable outcomes when applied in appropriate patients.

OBJECTIVE

The aim of the presented study is to investigate the parameters which may affect the outcomes of endoscopic injection and to compare the efficacy of two different bulking agents both composed of dextranomer-hyaluronic acid copolymer.

STUDY DESIGN

The data of patients who underwent endoscopic VUR treatment between 2003 and 2012 were retrospectively reviewed. Patients with history of previous open antireflux surgery, more than one failed endoscopic treatment for reflux, VUR caused by posterior urethral valve, duplex system and overt spinal dysraphism were excluded. Surgical technique was the classical STING method. One of the two dextranomer-hyaluronic acid copolymer agents was used (Deflux in 109 and Dexell in 131 patients). Both agents were composed of similar amounts of hyaluronic acid gel (15 mg in Deflux versus 17 mg in Dexell) but different sized dextranomer microspheres (80-250 μm in Deflux and 80-120 μm in Dexell). During the follow-up, ultrasonography was performed with 3-month interval, antibiotic prophylaxis was continued until the control voiding cystourethrography (VCUG) was taken. Patient based success was defined as the disappearance of reflux on control VCUG performed 3-6 months after the operation.

RESULTS

Data were available for 240 patients. Mean age and mean postoperative follow-up were 78 ± 41 months and 19 ± 18 months. The overall success rate was 73.2%. Gender, laterality, grade of VUR, presence of voiding dysfunction, renal scar and preoperative breakthrough infection (BTI) were not found to affect the outcome, whereas age younger than 54 months and previous history of failed endoscopic injection were found to negatively affect the outcome both in univariate and multivariate analysis. The postoperative UTI (5 febrile and 43 nonfebrile) rate was 20%. Both univariate and multivariate analysis showed that postoperative UTI was more common in patients with persisting reflux, with preoperative breakthrough infections and in girls. Patient characteristics, treatment outcome and postoperative UTI rate were similar regarding the used bulking agent. No ureteral obstruction was experienced within the follow-up period.

DISCUSSION

Our success rate for second injection is about 60%, which is significantly lower than for the patients who underwent first injection. We could not find any affecting factor for this difference. Contrary to the literature, our success rates were similar in different reflux grades. We can explain this finding that we value the intraoperative orifice configuration more than the grade which can be accepted as a patient selection bias. The lower success rate in children younger than 54 months can be explained by unstabilized bladder dynamics and higher voiding pressures in this age group, who are still in the toilet-training phase. Despite successful endoscopic treatment, UTI might occur. Postoperative UTI was more common in patients with persisting reflux, preoperative BTI and girls. The similar success rates of both bulking agents proved that dextranomer size does not affect the clinical outcome. Limitations of our study can be counted as follows: 1. the data do not include the number of patients in whom conversion to open surgery was decided intraoperatively because of the unfavorable orifice configuration, 2. our data do not include the injected volume records.

CONCLUSION

Endoscopic treatment of VUR has satisfying outcomes in properly selected cases. Younger age (<54 months) and previous history of failed injection history were found to be related to unfavorable results. Postoperative UTI occurs more frequently in patients with persisting reflux, preoperative breakthrough infection history and girls. The choice of one of the dextranomer-based substances does not affect the surgical outcome and postoperative UTI development.

Ureteroneocystostomy in primary vesicoureteral reflux: critical retrospective analysis of factors affecting the postoperative urinary tract infection rates

INTRODUCTION

To determine the parameters affecting the outcome of ureteroneocystostomy (UNC) procedure for vesicoureteral reflux (VUR).

MATERIALS AND METHODS

Data of 398 patients who underwent UNC procedure from 2001 to 2012 were analyzed retrospectively. Different UNC techniques were used according to laterality of reflux and ureteral orifice configuration. Effects of several parameters on outcome were examined. Disappearance of reflux on control VCUG or absence of any kind of UTI/symptoms in patients without control VCUG was considered as clinical improvement.

RESULTS

Mean age at operation was 59.2 ± 39.8 months and follow-up was 25.6 ± 23.3 months. Grade of VUR was 1-2, 3 and 4-5 in 17, 79, 302 patients, respectively. Male to female ratio was 163/235. UNC was performed bilaterally in 235 patients and intravesical approach was used in 373 patients. The frequency of voiding dysfunction, scar on preoperative DMSA, breakthrough infection and previous surgery was 28.4%, 70.7%, 49.3% and 22.4%, respectively. Twelve patients (8.9%) with postoperative contralateral reflux were excluded from the analysis. Overall clinical improvement rate for UNC was 92%. Gender, age at diagnosis and operation, laterality and grade of reflux, mode of presentation, breakthrough infections (BTI) under antibiotic prophylaxis, presence of voiding dysfunction and renal scar, and operation technique did not affect the surgical outcome. However, the clinical improvement rate was lower in patients with a history of previous endoscopic intervention (83.9% vs. 94%). Postoperative UTI rate was 27.2% and factors affecting the occurrence of postoperative UTI were previous failed endoscopic injection on univariate analysis and gender, preoperative BTI, postoperative VUR state, voiding dysfunction on multivariate analysis. Surgery related complication rate was 2% (8/398). These were all low grade complications (blood transfusion in 1, hematoma under incision in 3 and prolonged hospitalization secondary to UTI in 4 patients). In long term, 12 patients are under nephrologic follow-up because of hypertension in 5, increased serum creatinine in 5, proteinuria in 1 and hematuria in 1 patient and all these patients had preoperative scarred kidneys.

CONCLUSIONS

Despite its invasive nature, UNC has a very high success rate with a negligible percent of complications. In our cohort, the only factor that negatively affected the clinical improvement rate was the history of previous antireflux interventions where the predictive factors for postoperative UTI were previous failed endoscopic injection, female gender, preoperative BTI, persistent VUR and voiding dysfunction.

Can intrauterine death of a co-twin result in renal failure in the survivor?

Multiple pregnancies are characterized by significantly higher rates of intrauterine and perinatal morbidities and fetal death compared to singleton pregnancies. It is well known that the death of a co-twin during the second and third trimester can cause damage in the other fetus. Here we report two newborn cases presenting with renal failure probably caused by intrauterine death of their co-twins shortly before birth.

[Pediatric renal transplantation in France. Introduction]

Pediatric nephrology is a relatively recent medical speciality. The first French center opened in January 1969 at the Hospital des Enfants-Malades. In 2008, according to the Réseau Épidémiologie et Information en Néphrologie (REIN), the annual incidence of end stage renal disease (ESRD) was of 7,8 children/million children below the age of 20, which equals a prevalence of 49 pediatric ESRD patients/million inhabitants. The frequency of causative factors of ESRD varies according to the geographic and ethnic origin of the patients. Many challenges still lay ahead of ESRD management. The children's physical, psychological and social development has to be well taken care of until adulthood and the transition from pediatric to adult unit has to be handled with special care. The set up of pediatric nephrology departments helped to the access of patients to renal replacement therapy, in particular the pediatric priority for kidney donors below 30 years of age. In the 2000s period, the annual rate of pediatric renal transplantation was 70 to 75 grafts per year in France, half of which performed in the Paris area. This article presents the historical background of pediatric nephrology and pediatric renal transplantation in France.

Impact of peritoneal transport characteristics on cardiac function in paediatric peritoneal dialysis patients: a Turkish Pediatric Peritoneal Dialysis Study Group (TUPEPD) report

BACKGROUND

The peritoneal equilibration test (PET) is recommended in paediatric peritoneal dialysis (PD) patients to assist prescription management. Despite contradictory reports, high transporter status is associated with reduced survival rate in adults. Since cardiac disease is one of the main causes of mortality in paediatric PD patients, we aimed to evaluate whether transport features have any effect on biochemical data and cardiac function in this group.

METHODS

One hundred and ten PD patients (13 +/- 5 years, PD vintage: 31 +/- 27 months) were enrolled into the study. Four-hour dialysate/plasma creatinine ratio was used for differentiating PET groups. Thirty-eight patients were high transporters, 29 were high-average transporters and 43 were low-average/low transporters. Echocardiography was performed in all subjects.

RESULTS

Age, PD vintage, dialysate glucose concentration, ultrafiltration volume, urine volume and blood pressure levels were similar in all PET groups. No biochemical or echocardiographic data (ejection fraction, fractional shortening, left ventricular mass index, myocardial performance index, power Doppler E/tissue Doppler E ratio reflecting diastolic function) were different among PET groups except lower albumin (P = 0.025) levels in high transporters and higher high-sensitivity C-reactive protein (P = 0.026) levels in high and high-average transporters compared to other transport groups.

CONCLUSIONS

Cardiac structural and functional abnormalities are highly prevalent among paediatric PD patients. Transport rates did not have a significant effect on biochemical parameters or cardiac structural/functional parameters. It might be suggested that being a high transporter does not provide a disadvantage in terms of atherogenic tendency and cardiac disease in paediatric PD patients. Oligoanuria, anaemia and hypertension were independent predictors of cardiac disease.

Peritonitis rates and common microorganisms in continuous ambulatory peritoneal dialysis and automated peritoneal dialysis

BACKGROUND

The aim of the present study was to perform a multicenter investigation in Turkish children on chronic peritoneal dialysis by examining the rates of peritonitis as well as causative organisms according to year.

METHODS

Twelve pediatric renal units participated in this study and data were obtained by review of the medical records.

RESULTS

One hundred and thirty-two patients were on continuous ambulatory peritoneal dialysis (CAPD), 21 were on automated peritoneal dialysis (APD) and 59 were on CAPD and APD at different times. Mean durations of CAPD and APD were 24.2 +/- 21.1 months and 22.9 +/- 12.8 months, respectively. Seventy-one (33%) out of 212 patients had no peritonitis episode. Overall peritonitis rate was one episode per 15.5 patient-months. The peritonitis rate was one episode per 15.4 patient-months for APD and one episode per 15.6 patient-months for CAPD. Coagulase-negative staphylococcus was the most common cause of peritonitis among patients with positive culture (20.6%). While the incidence of Gram-negative infection remained unchanged according to year in patients on CAPD (P = 0.68), the rate of Gram-negative peritonitis in children on APD was significantly higher (P = 0.03).

CONCLUSIONS

Peritonitis rate was similar in CAPD and APD, but the risk of Gram-negative peritonitis in APD was higher than that of CAPD.

Chronic kidney disease in children in Turkey

To determine the incidence, etiology and treatment patterns of chronic kidney disease (CKD) in children a questionnaire was sent to pediatric nephrology centers in Turkey, asking them to report patients under the age of 19 years who had estimated glomerular filtration rates (GFRs) of <or=75 ml/min per 1.73 m(2) body surface area, diagnosed in 2005. Twenty-nine centers reported 282 patients (123 female/159 male; mean age 8.05 +/- 5.25 years). Urological problems such as vesicoureteral reflux (18.5%), obstructive uropathy (10.7%) and neurogenic bladder (15.1%) were the leading causes of CKD. The majority of the patients were in stage V (32.5%), IV (29.8%) or III (25.8%). Growth retardation (49.6%) and secondary hyperparathyroidism (72.4%) were very frequent. The GFR levels correlated positively with hemoglobin/hematocrit and calcium levels and negatively with phosphorus and parathyroid hormone (PTH) levels (P < 0.05). Renal replacement therapies were initiated in 35.8% of the patients, peritoneal dialysis in 23%, hemodialysis in 10.6% and transplantation in 2.2%. This was the first multi-center, epidemiologic study done in children with CKD in Turkey. The most striking result was the predominance of vesicoureteral reflux (VUR) or related urological problems as the underlying causes of CKD. Thus, early diagnosis and treatment of these conditions are of vital importance to decrease the incidence of CKD in children.

Challenges in pediatric peritoneal dialysis in Turkey

Chronic peritoneal dialysis (CPD) is the modality of choice for children with end-stage renal disease in Turkey. CPD was first instituted in 1989 in Turkish pediatric patients by using imported basic equipment and solutions since then the number of patients on CPD increased gradually. Parallel to the developments in the PD industry, in 2002, the Turkish Pediatric Nephrology Association established the Turkish Pediatric Peritoneal Dialysis (TUPEPD) Study Group to study peritoneal dialysis in children and adolescents. Today in Turkey, almost all of the PD equipment and PD solutions are available. Turkish pediatric nephrologists now have a significant experience with PD. Physicians, parents, and the children prefer to start with CPD because of its advantages, such as a more liberal social life and better school attendance.

Chronic kidney disease in children: the global perspective

In contrast to the increasing availability of information pertaining to the care of children with chronic kidney disease (CKD) from large-scale observational and interventional studies, epidemiological information on the incidence and prevalence of pediatric CKD is currently limited, imprecise, and flawed by methodological differences between the various data sources. There are distinct geographic differences in the reported causes of CKD in children, in part due to environmental, racial, genetic, and cultural (consanguinity) differences. However, a substantial percentage of children develop CKD early in life, with congenital renal disorders such as obstructive uropathy and aplasia/hypoplasia/dysplasia being responsible for almost one half of all cases. The most favored end-stage renal disease (ESRD) treatment modality in children is renal transplantation, but a lack of health care resources and high patient mortality in the developing world limits the global provision of renal replacement therapy (RRT) and influences patient prevalence. Additional efforts to define the epidemiology of pediatric CKD worldwide are necessary if a better understanding of the full extent of the problem, areas for study, and the potential impact of intervention is desired.

Comparison of chronic peritoneal dialysis outcomes in children with and without spina bifida

This study was designed to compare chronic peritoneal dialysis (CPD) long-term outcomes (patient and technique survival, incidence of peritonitis, and overall average death outcomes) between seven patients with lumbar spina bifida (SB) and 20 controls without SB. Both groups were matched for potentially outcome-confounding factors: gender, and socioeconomic status (SES). SES was established using modified Graffar's method. No significant differences were found in CPD outcomes. The incidence of peritonitis was one episode per 17.6 and 10.3 months in SB patients and controls, respectively (p = 0.5). Overall patient survival at 5 years was 86% and 73% in SB patients and controls, respectively (p = 0.55). Overall average death rate between SB and control patients was 47.6/1,000 and 79.4/1,000 patient years, respectively (p = 0.63). Overall technique survival at 5 years was 83% and 73% in SB patients and controls, respectively (p = 0.84). There were no cases of retrograde brain ventricular infection secondary to PD-related peritonitis. We conclude that SB is not a risk factor for CPD, and therefore, it is an effective renal replacement alternative in children with SB.