Factors Predisposing and Contributing to Peritonitis during Chronic Peritoneal Dialysis in Children: A Ten-Year Experience

Factors contributing and predisposing to peritonitis were studied retrospectively in 83 children treated with continuous ambulatory (CAPD) or continuous cycling peritoneal dialysis (CCPD) from 1978 to 1988. Recurrent peritonitis was the most frequent complication and the major reason for peritoneal dialysis failure. Fifty patients had 171 episodes of peritonitis during the ten years and 33 remained peritonitis -free. The duration of dialysis was significantly shorter in the peritonitis-free group. The incidence of peritonitis was lower with CCPD than with CAPD. Leucopenia was not a predisposing factor nor was blood leucocytosis helpful in diagnosing peritonitis. Serum IgG was low in 33% of patients with episodes of peritonitis, but there was no correlation or predictive value in this finding. The C3 component of complement was relatively lower than the C4 but both components were usually in the normal range. Serum albumin was low in all patients, but lower in those with peritonitis episodes. Age, sex, primary disease, diapers, pyelostomies, dialysis training, and living conditions were not significantly associated risk factors. Sterile dressings gave no benefit over the shower technique. Patient noncompliance, upper respiratory tract infection, skin infections, and dental treatment were potential risk factors. However, peritonitis seemed to be distributed randomly among the patients.

Outcomes of percutaneous transluminal angioplasty for pediatric renovascular hypertension

BACKGROUND

Up to 10% of hypertensive children will have renovascular disease. Where medical therapy fails to control the hypertension, endovascular techniques can improve renal perfusion. The purpose of this study was to assess the efficacy of angioplasty in controlling renovascular hypertension (RVH) in children.

METHODS

This is a single-center, retrospective review of patients who underwent angioplasty for RVH between 1992 and 2009. All patients were selected from the Interventional Radiology database. The primary outcome measure was clinical success as reflected by a favorable, sustained response in blood pressure for at least 1year following the angioplasty.

RESULTS

Two hundred sixteen patients underwent diagnostic angiography for suspected RVH, of these 28 required 42 angioplasties. Ten (36%) were cured, 9 (32%) were improved and 9 (32%) failed to respond to treatment. Major complications occurred in three patients and minor complications occurred in 18 angioplasties. Fibromuscular dysplasia (FMD) was the most common diagnosis in this series and was associated with a 79% success rate.

CONCLUSION

In our exclusively pediatric population angioplasty safely improved blood pressure control in 68% of patients, more than half of which are cured. FMD appeared to have the best clinical outcomes in our series.

Ethnic Differences in Incidence and Outcomes of Childhood Nephrotic Syndrome

BACKGROUND AND OBJECTIVES

Ethnic differences in outcomes among children with nephrotic syndrome are unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a longitudinal study at a single regional pediatric center comparing ethnic differences in incidence from 2001 to 2011 census data and longitudinal outcomes, including relapse rates, time to first relapse, frequently relapsing disease, and use of cyclophosphamide. Among 711 children, 24% were European, 33% were South Asian, 10% were East/Southeast Asian, and 33% were of other origins.

RESULTS

Over 10 years, the overall incidence increased from 1.99/100,000 to 4.71/100,000 among children ages 1-18 years old. In 2011, South Asians had a higher incidence rate ratio of 6.61 (95% confidence interval, 3.16 to 15.1) compared with Europeans. East/Southeast Asians had a similar incidence rate ratio (0.76; 95% confidence interval, 0.13 to 2.94) to Europeans. We determined outcomes in 455 children from the three largest ethnic groups with steroid-sensitive disease over a median of 4 years. South Asian and East/Southeast Asian children had significantly lower odds of frequently relapsing disease at 12 months (South Asian: adjusted odds ratio; 0.55; 95% confidence interval, 0.39 to 0.77; East/Southeast Asian: adjusted odds ratio; 0.42; 95% confidence interval, 0.34 to 0.51), fewer subsequent relapses (South Asian: adjusted odds ratio; 0.64; 95% confidence interval, 0.50 to 0.81; East/Southeast Asian: adjusted odds ratio; 0.47; 95% confidence interval, 0.24 to 0.91), lower risk of a first relapse (South Asian: adjusted hazard ratio, 0.74; 95% confidence interval, 0.67 to 0.83; East/Southeast Asian: adjusted hazard ratio, 0.65; 95% CI, 0.63 to 0.68), and lower use of cyclophosphamide (South Asian: adjusted hazard ratio, 0.82; 95% confidence interval, 0.53 to 1.28; East/Southeast Asian: adjusted hazard ratio, 0.54; 95% confidence interval, 0.41 to 0.71) compared with European children.

CONCLUSIONS

Despite the higher incidence among South Asians, South and East/Southeast Asian children have significantly less complicated clinical outcomes compared with Europeans.

Gaining the PROMIS perspective from children with nephrotic syndrome: a Midwest pediatric nephrology consortium study

Background and objectives

Nephrotic syndrome (NS) represents a common disease in pediatric nephrology typified by a relapsing and remitting course and characterized by the presence of edema that can significantly affect the health-related quality of life in children and adolescents. The PROMIS pediatric measures were constructed to be publically available, efficient, precise, and valid across a variety of diseases to assess patient reports of symptoms and quality of life. This study was designed to evaluate the ability of children and adolescents with NS to complete the PROMIS assessment via computer and to initiate validity assessments of the short forms and full item banks in pediatric NS. Successful measurement of patient reported outcomes will contribute to our understanding of the impact of NS on children and adolescents.

Design

This cross-sectional study included 151 children and adolescents 8-17 years old with NS from 16 participating institutions in North America. The children completed the PROMIS pediatric depression, anxiety, social-peer relationships, pain interference, fatigue, mobility and upper extremity functioning measures using a web-based interface. Responses were compared between patients experiencing active NS (n = 53) defined by the presence of edema and patients with inactive NS (n = 96) defined by the absence of edema.

Results

All 151 children and adolescents were successfully able to complete the PROMIS assessment via computer. As hypothesized, the children and adolescents with active NS were significantly different on 4 self-reported measures (anxiety, pain interference, fatigue, and mobility). Depression, peer relationships, and upper extremity functioning were not different between children with active vs. inactive NS. Multivariate analysis showed that the PROMIS instruments remained sensitive to NS disease activity after adjusting for demographic characteristics.

Conclusions

Children and adolescents with NS were able to successfully complete the PROMIS instrument using a web-based interface. The computer based pediatric PROMIS measurement effectively discriminated between children and adolescents with active and inactive NS. The domain scores found in this study are consistent with previous reports investigating the health-related quality of life in children and adolescents with NS. This study establishes known-group validity and feasibility for PROMIS pediatric measures in children and adolescents with NS.

Primary antiphospholipid syndrome presenting as renal vein thrombosis and membranous nephropathy

Antiphospholipid syndrome is a multisystem auto-immune disorder characterized by thrombotic events and the presence of circulating antiphospholipid antibodies. Large vessel involvement in the form of thrombosis/stenosis and thrombotic microangiopathy is a commonly described renal finding. However, non-thrombotic glomerulopathies are increasingly being recognized in patients with antiphospholipid syndrome. We report a rare occurrence of both renal vein thrombosis and membranous nephropathy in a previously healthy adolescent male. Investigations revealed persistently positive antiphospholipid antibodies in the absence of an underlying systemic autoimmune disorder or malignancy. Our patient responded favourably to anti-proteinuric therapy and anticoagulation with complete resolution of proteinuria and a nearly occlusive thrombus.

Rituximab in refractory nephrotic syndrome

The aim of this study was to establish the efficacy and safety of rituximab in refractory nephrotic syndrome (NS). Members of the International Paediatric Nephrology Association were asked to retrospectively fill in a questionnaire with details on the use of rituximab in their centres. We divided the data into three groups: group 1, patients with steroid-dependent and frequently relapsing NS; group 2, with steroid-resistant NS; group 3, with post-transplant recurrence of NS. Seventy questionnaires from 25 centres described the outcome of 28, 27 and 15 patients in groups 1, 2 and 3, respectively. Of these, 82% of patients in group 1, 44% of patients in group 2 and 60% of patients in group 3 had a good initial response. Side effects were observed in 27% of the patients, and these were mostly acute reactions. We present a large multicentre series of children with refractory NS. Children in group 1 showed the best response. The good initial response in group 3 can be biased by the accompanying treatments that were administered at the same time as rituximab. Controlled prospective trials are required to establish the value of rituximab in idiopathic NS.

Compliance with a pediatric clinical practice guideline for intravenous fluid and electrolyte administration

The occurrence of acute hyponatremia associated with cerebral edema in hospitalized children has been increasingly recognized, with over 50 cases of neurological morbidity and mortality reported in the past decade. This condition most commonly occurs in previously healthy children where maintenance intravenous (IV) fluids have been prescribed in the form of hypotonic saline (e.g., 0.2 or 0.3 NaCl). In response to similar problems at The Hospital for Sick Children (six identified through hospital morbidity and mortality reviews and safety reports prior to fall 2007), an interdisciplinary clinician group from our institution developed a clinical practice guideline (CPG) to guide fluid and electrolyte administration for pediatric patients. This article reviews the evaluation of one patient safety improvement to change the prescribing practice for IV fluids in an acute care pediatric hospital, including the removal of the ability to prescribe hypotonic IV solutions with a sodium concentration of < 75 mmol/L. The evaluation of key components of the CPG included measuring practice and process changes pre- and post-implementation. The evaluation showed that the use of restricted IV fluids was significantly reduced across the organization. Success factors of this safety initiative included the CPG development, forcing functions, reminders, team engagement and support from the hospital leadership. A key learning was that a project leader with considerable dedicated time is required during the implementation to develop change concepts, organize and liaise with stakeholders and measure changes in practice. This project highlights the importance of active implementation for policy and guideline documents.

The value of sequential dialysis, mannitol and midodrine in managing children prone to dialysis failure

The uremic state impairs compensatory responses to ultrafiltration (UF). Intradialytic symptoms and hypotension can result and lead to premature discontinuation of treatment and sub-optimal dialysis. We report the benefits of mannitol, sequential dialysis and midodrine in reducing dialysis failures in those children prone to intradialytic hypotension. Prophylactic mannitol halved the odds of intradialytic symptoms and hypotension and increased UF volumes. Sequential dialysis halved the odds of symptoms but hypotension persisted. In one patient with refractory hypotension, only intradialytic midodrine consistently maintained acceptable intradialytic blood pressures, reduced intradialytic symptoms and increased the UF potential.

Sevelamer hydrochloride: a novel treatment of hyperphosphatemia associated with tumor lysis syndrome in children

BACKGROUND

Sevelamer is a phosphate-binder used effectively for the treatment of hyperphosphatemia in patients treated with dialysis.

OBJECTIVES

To describe the safety of sevelamer in children with hyperphosphatemia secondary to tumor lysis syndrome and the serum phosphate concentrations observed following its administration.

PROCEDURE

A retrospective chart review of all children with leukemia/lymphoma diagnosed between November 2002 and April 2004 who received sevelamer during their initial admission was conducted. We monitored the effects of sevelamer on serum phosphate concentration, calcium/phosphate product and renal function at hours 24, 48, and 72 from sevelamer initiation.

RESULTS

Thirteen patients received sevelamer during the study period. Their median age was 13 years (range 2.7-17.9) and eight were boys. Nine children had acute lymphoblastic leukemia, one had acute myeloid leukemia and 3 had non-Hodgkin's lymphoma. The most frequently used dose of sevelamer was 400 mg orally twice daily. The median duration of sevelamer therapy was 2 days (range 1-7). Two children were excluded from the efficacy analysis due to concurrent use of dialysis. Mean serum phosphate levels decreased after sevelamer administration, in eleven patients, from a baseline 2.2 mmol/L +/- 0.4 (95% CI, 1.7-3.1) to 1.1 mmol/L +/- 0.2 at hour 72 (95%CI, 0.6-1.5). The only toxicity attributed to sevelamer was mild vomiting in three patients.

CONCLUSIONS

Sevelamer appears to be effective and tolerable for the treatment of hyperphosphatemia associated with tumor lysis syndrome.

Atypical p-ANCA is not a poor prognostic marker in Postinfectious Glomerulonephritis

Postinfectious glomerulonephritis (PIGN) most commonly follows streptococcal infection. Antineutrophil cytoplasmic antibodies (ANCA) are characteristically negative in PIGN. We report on five cases who had positive atypical pANCA at presentation. The outcome was typical of other cases of PIGN with complete resolution of the glomerulonephritis in all five patients. Atypical pANCA occurs in a number of inflammatory conditions and antigenic targets may include proteins other than myeloperoxidase or proteinase 3. The presence of atypical p-ANCA does not indicate a poor prognosis.

Frequent hemodialysis in children

Frequent hemodialysis is currently conducted in a limited number of pediatric dialysis centers. However, the preliminary experience with children who have undergone procedures such as "daily" intensive hemodiafiltration and nocturnal hemodialysis has been positive, with the allowance for unrestricted diets and fluid intake, the lack of need for phosphate binders, excellent metabolic and blood pressure control, and, in the case of hemodiafiltration, excellent growth. The provision of frequent daily hemodialysis with the NxStage System has also recently been introduced to pediatrics. An overview about what is currently understood regarding the technical and clinical application of these approaches to therapy for children with end-stage renal disease form the basis for this article and highlight the impact of the procedures to date and the need for additional experience and collaborative data collection.

Phase I and pharmacokinetic (PK) study of PTK787/ZK222584 (PTK/ZK) plus capecitabine (cape) in patients (Pts) with advanced cancer

3595

Background: PTK/ZK is a small molecule inhibitor of the vascular endothelial growth factor receptor family. Cape is a standard treatment for pts with breast and colon cancer, tumors for which angiogenesis inhibition is beneficial. Therefore, we conducted a phase I study of the combination to determine the maximally tolerated doses (MTD), toxicities and PK interactions. Methods: Eligible pts had advanced cancer with no standard treatment option, Karnofsky performance status (KPS) > 70, and normal organ function. Pts with bone marrow or CNS involvement or who had more than 4 prior chemotherapy regimens were excluded. A dose escalation (dosesc) phase was conducted to determine the MTD followed by a dose expansion (dosexp) phase to assess PK interactions. PTK/ZK was given as a single oral daily doser without interruption and cape was given orally twice daily for 14 of 21 days. Results to Date: 43 pts (30 male, 13 female), median age 61 y (34–78 y) and median KPS 95 (70–100) were enrolled in the dosesc phase. 37 had prior chemotherapy; 5 had radiation only. Diagnoses included colorectal cancer (10), head/neck (7), sarcoma (5), renal (4), stomach/pancreas (3 each) and others (11). 29/43 pts were evaluable for MTD determination and received a total of 145 cycles. Doses of PTK/ZK-cape (mg-mg/m2) were: 750/2,500; 1,000/2,500; 750/2,000; 1,000/2,000; 1,250/2,000. DLT occurred in 1/6 pts (gr 3 fatigue) at 750/2,500; 2/2 pts (≥gr 3 fatigue, hypertension [HTN]) at 1,000/2,500; 0/3 pts at 750/2,000; 2/12 pts (≥ gr 3 dizziness, HTN and seizure) at 1,000/2,000 and in 1/6 (gr 3 proteinuria) pts at 1,250/2,000. 1,250 mg was the highest PTK/ZK dose planned. Other common toxicities in the dosesc phase were hand-foot syndrome (HFS, 93%) and HTN (28%). In the dosexp phase 26 pts (14 M, 12 F) have thus far received 73 cycles at the MTD (1,250/2,000). Median age is 65 y (26–79 y) and median KPS is 80 (70–100). 28/73 cycles were delayed or interrupted for toxicity with gr ≥3 toxicities (# cycles): HFS (7), fatigue (5), increased LFTs (5), HTN (3), DVT/PE (4). 23 pts (17 in dosesc and 6 in dosexp) had response or stable disease longer than 12 weeks. Final results and PK data will be presented. Conclusion: PTK/ZK and cape can be combined without unexpected toxicities.

No significant financial relationships to disclose.

Cerebral sinovenous thrombosis and idiopathic nephrotic syndrome in childhood: report of four new cases and review of the literature

INTRODUCTION

Nephrotic children are prone to develop thromboembolic complications secondary to an acquired hypercoagulable state. Cerebral sinovenous thrombosis (CSVT) is increasingly recognised in this population, but clinical characteristics and outcome are not well documented.

PATIENTS AND METHODS

The database of the Canadian Pediatric Ischemic Stroke Registry (Toronto Site) containing prospectively enrolled children from 1992-2004 with CSVT identified four children with NS. A pooled literature analysis retrieved 17 additional cases reports.

RESULTS

CSVT presented in the majority of cases during the first flare or within 6 months after the onset of NS and was found to occur more often in SSNS/SDNS (n=13) than in SRNS (n=4). Clinical manifestations were non-specific and consisted primarily of seizures (n=8) and signs of raised intracranial pressure (n=16). Imaging studies revealed a predilection for superior sagittal sinus involvement (n=21) and rare parenchymal lesions (n=4). The most consistent biological risk factors were a severe hypoalbuminaemia (n=14) and, to a lesser extent, decreased antithrombin (AT) levels (n=9/16). Deficiency of other coagulation inhibitors (protein S, protein C) was not identified. Inherited thrombophilia was documented in a single case, suggesting that acquired, more than genetic, coagulation factors are involved. Anticoagulation was safe, and the outcome was good in most patients, and no recurrence of thrombotic event was reported.

DISCUSSION

In conclusion, CSVT is now a well-described complication of NS with potential morbidity. A high index of suspicion is required, especially in young children with NS presenting neurological symptoms. Reliable biological predictors of CSVT are lacking.

Severe cardiac hypertrophy and long-term dialysis: the Midwest Pediatric Nephrology Consortium study

Cross-sectional studies have demonstrated that left ventricular hypertrophy (LVH) is common in children on maintenance dialysis. We report the echocardiogram results of 17 children from seven centers in the Midwest Pediatric Nephrology Consortium who have spent at least 2 years on maintenance dialysis and had three consecutive echocardiograms: at initiation of dialysis therapy and 1 and 2 years later. The results indicate that LVH is prevalent at the initiation of dialysis (82%) and remains both frequent (82%) and severe (59%) after 2 years of maintenance dialysis. Normalization of LV geometry was unlikely: the prevalence of concentric LVH increased and the prevalence of eccentric LVH did not change over time, indicating poor blood pressure and volume status control in these patients. We conclude that children on maintenance dialysis are at high risk for future cardiovascular disease.

Management of severe hypertension in a child with tuberous sclerosis-related major vascular abnormalities

OBJECTIVE

We report the case of a 4-year-old girl with tuberous sclerosis who presented with severe renovascular hypertension secondary to compression of the renal arteries by a large infradiaphragmatic abdominal aortic aneurysm.

DESIGN

Case report of a previously unreported case.

RESULTS

Normotension could not be achieved despite conservative treatment with three antihypertensive drugs at high doses. An aortic graft was performed successfully but failed to correct the hypertension. Postoperatively, the child experienced acute renal failure after attempting treatment with additional enalapril. Further investigations revealed ischaemia of the left kidney and stenosis of the right renal artery. Subsequently, a combination of maximum dose minoxidil, a calcium antagonist, clonidine and peripheral alpha and beta-blockers, and diuretics was used, but her blood pressure control remained poor. A bypass between the hepatic artery and the right renal artery restenosed at the proximal anastomosis. Her renovascular hypertension was finally improved with an autotransplantation of her right kidney into the right iliac fossa. Fibromuscular dysplasia and abundant collagen deposition were the predominant features seen on histology. She is currently normotensive on moderate doses of a beta-blocker, amlodipine and a diuretic.

CONCLUSION

Hypertension in this case was impossible to control medically, and the surgical approach was compromised by numerous complications. This case illustrates the challenges in the management of renovascular hypertension in a child with disease-associated vascular malformations.

Ambulatory blood pressure monitoring: mean blood pressure and blood pressure load

Ambulatory blood pressure monitoring (ABPM) is commonly used to diagnose pediatric hypertension. Using ABPM, hypertension is usually defined as a mean BP greater than the 95th percentile for height. A BP load >30% (% of BP readings greater than the 95th percentile) is also used for the diagnosis of hypertension. The objective of this study was to determine the agreement between mean BP greater than the 95th percentile and 30% BP load for the diagnosis of hypertension using ABPM. All ABPM records (n =1,009) of patients referred for hypertension to a pediatric center were retrieved. Scans were excluded if: age was >19 and height <115 cm or >185 cm. Mean BP and BP loads were calculated for 728 scans. Agreement between mean BP greater than the 95th percentile for height and various BP loads were calculated using the kappa coefficient. The kappa coefficient of agreement between mean BP greater than the 95th percentile and 30% BP load was 0.56 and 0.57 for daytime systolic and diastolic BP, respectively. The agreement between mean night-time BP greater than the 95th percentile and 30% BP load was 0.70 and 0.66 for systolic and diastolic BP, respectively. Agreement between mean BP greater than the 95th percentile and 30% BP load is only moderate to good. Maximum agreement between mean BP greater than the 95th percentile and BP load is achieved at 50% BP load.

Acute hyponatremia related to intravenous fluid administration in hospitalized children: an observational study

OBJECTIVE

To develop hyponatremia (plasma sodium concentration [P(Na)] <136 mmol/L), one needs a source of water input and antidiuretic hormone secretion release to diminish its excretion. The administration of hypotonic maintenance fluids is common practice in hospitalized children. The objective of this study was to identify risk factors for the development of hospital-acquired, acute hyponatremia in a tertiary care hospital using a retrospective analysis.

METHODS

All children who presented to the emergency department in a 3-month period and had at least 1 P(Na) measured (n = 1586) were evaluated. Those who were admitted were followed for the next 48 hours to identify patients with hospital-acquired hyponatremia. An age- and gender-matched case-control (1:3) analysis was performed with patients who did not become hyponatremic.

RESULTS

Hyponatremia (P(Na) <136 mmol/L) was documented in 131 of 1586 patients with > or = 1 P(Na) measurements. Although 96 patients were hyponatremic on presentation, our study group consisted of 40 patients who developed hyponatremia in hospital. The case-control study showed that the patients in the hospital-acquired hyponatremia group received significantly more EFW and had a higher positive water balance. With respect to outcomes, 2 patients had major neurologic sequelae and 1 died.

CONCLUSION

The most important factor for hospital-acquired hyponatremia is the administration of hypotonic fluid. We suggest that hypotonic fluid not be given to children when they have a P(Na) <138 mmol/L.

Possible role of new pressor protein in hypertensive anephric hemodialysis patients

Unexplained hypertension was observed in three anephric children on hemodialysis. We investigated the possible involvement of a novel hypertensive extra-renal enzyme new pressor protein (NPP), related to coagulation beta-FXIIa. Currently, NPP activity can only be determined by a rat bioassay model. On study day 1, pre dialysis, patients 1, 2, and 3 were hypertensive and their plasmas raised rat systolic blood pressure (SBP) by 45, 34, and 9 mmHg, respectively. Post dialysis, patients 1 and 2 reached their estimated dry body weight and their systemic pressures dropped, while patient 3 remained hypertensive and hypervolemic. Their post-dialysis plasmas raised rat SBP by 22, 14, and 9 mmHg, respectively. On day 2, similar relationships between patient SBP, volume status, and plasma NPP-like activity in rats were observed. The characteristic rat BP responses, lack of inhibition by captopril (ruling out a renin-mediated effect), and inhibition by soybean trypsin inhibitor support co-identity with NPP. Plasma FXIIa (combined alpha-FXIIa and beta-FXIIa) was measured by immunoassay and found to be elevated in all patients. This investigation suggests that there is high endogenous NPP activity in the plasmas of these hypertensive hemodialysis patients, it changes with SBP and fluid volume, and is a possible contributor to their hypertension. Further studies are required to examine the wider applicability of these novel findings.

Outcome analysis of vesicoamniotic shunting in a comprehensive population

PURPOSE

Prenatal detection of obstructive uropathy is used widely and vesicoamniotic shunting is the accepted procedure in well-defined cases. We present outcomes of vesicoamniotic shunting in a consecutive series from a coordinated prenatal-postnatal treatment program.

MATERIALS AND METHODS

From 1989 to 1998 bladder obstruction was identified in 89 fetuses at a multidisciplinary prenatal high risk clinic. Prenatal intervention was considered in cases of bilateral hydronephrosis associated with evidence of bladder outlet obstruction and oligohydramnios.

RESULTS

Indications for prenatal shunting were present in 12 patients (13%), and 9 underwent vesicoamniotic shunt insertion between weeks 20 and 28 of gestation. None of the prenatal procedures was associated with preterm labor, chorioamnionitis or urine chemistry values greater than cutoff threshold on bladder tap. Shunts were extruded from 2 fetuses, which required sequential insertion. After prenatal intervention 1 patient elected pregnancy termination and the others proceeded to term. Two neonates died at birth, and 6 survived. The underlying urological diagnosis was posterior urethral valves in 4 newborns, urethral atresia in 1, and prune belly variant and urethral atresia in 1. Of the patients 3 had relatively normal renal function, 2 had severe renal insufficiency and 1 had mild renal impairment. Five newborns are voiding freely and 1 underwent bladder reconstruction and is on intermittent catheterization. None of the patients had pulmonary problems at last followup.

CONCLUSIONS

Although vesicoamniotic shunting is effective in reversing oligohydramnios, its ability to achieve sustainable good renal function in infancy is variable. No specific prenatal parameters were effective in predicting eventual good renal function. Pulmonary function cannot be assured with restoration of amniotic fluid.

Polyuria and proteinuria in cystinosis have no impact on renal transplantation. A report of the North American Pediatric Renal Transplant Cooperative Study

Because cystinotic patients are polyuric and may have severe proteinuria, each of which is a potential risk factor for graft thrombosis, preemptive transplantation for them is questionable. The objectives of this study were to characterize the changes in urine volume and protein excretion at various stages of cystinosis, determine whether there is serologic evidence of hypercoagulability, and review the clinical experience in renal transplantation in cystinotic children. The records of cystinotic patients followed at the Montreal Children's Hospital between 1992 and 1998 were reviewed. Urinary volume, protein excretion, and coagulation markers were collected to determine the glomerular filtration rate (GFR) >50 ml/min/1.73 m2, <20 ml/min/1.73 m2, before and after starting dialysis. In addition, graft failure and graft thrombosis rates were obtained from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) database. Urinary volume and protein excretion remained elevated throughout different phases of the disease. Coagulation factors were within normal limits for all patients. In the NAPRTCS database there were four thromboses among the 114 patients transplanted cystinotic patients. All these occurred in cadaveric grafts and only one occurred after preemptive transplantation. Despite polyuria and severe proteinuria, children with cystinosis do not appear to be at an increased risk of graft failure or graft thrombosis.

The natural history of neonatal vesicoureteral reflux associated with antenatal hydronephrosis

PURPOSE

In an attempt to evaluate the natural history of neonatal vesicoureteral reflux, patients with antenatal history of hydronephrosis and documented reflux in the first 30 days of life were analyzed.

MATERIALS AND METHODS

Between 1993 and 1998, 260 patients with a history of antenatal hydronephrosis were referred for evaluation. Of these patients 31 were diagnosed with unilateral or bilateral refluxing renal units (54 renal units). Patients were treated with a prospective plan of observational therapy and prophylactic antibiotics, and resolution rate was calculated in patients with adequate followup. Reflux grade was correlated with postnatal ultrasonographic findings, urinary tract infections and differential renal function. Outcome analysis of 34 high grade (III to V) refluxing renal units using the Kaplan-Meier survival curves was undertaken with the end point being complete resolution or improvement. Three patients with vesicostomy and 2 who underwent ureteral reimplantation were excluded from analysis.

RESULTS

Reflux was grade I in 5% (33% males), II in 15% (62% males), III in 32% (71% males), IV in 18% (90% males) and V in 30% (100% males) of the patients. Postnatal ultrasound findings correlated poorly with the presence and degree of vesicoureteral reflux. Of 17 patients followed for at least 14 months (average followup 20) there was complete resolution in 60% with grade III, 50% with grade IV and 28% with grade V reflux. Using the Kaplan-Meier estimate there was a 50% chance of improvement (decrease in reflux grade by at least 2 grades) in high grade reflux by age 16 months. Urinary tract infections developed in 8 patients (26%) while on antibiotics. Of 46 renal units in 23 patients evaluated with a renal scan before urinary tract infection, 12 had less than 35% function.

CONCLUSIONS

A normal postnatal ultrasound should not be a basis for excluding the use of cystography. Our Kaplan-Meier estimate shows that high grade reflux does improve and may resolve spontaneously. In addition, renal scarring may be seen with high and low grade reflux in the absence of urinary tract infection but high grade reflux is associated with a higher incidence of infection.

Multiple unilateral renal cysts in two children

We report two children who presented with multiple renal cysts involving only one kidney and in whom there was no family history of renal disease and who did not have syndromes known to be associated with renal cystic disease. This unilateral involvement may represent a distinct entity, which has only been previously described in three cases; however, long-term follow-up will be needed to confirm this hypothesis. We illustrate the sonographic and computed tomographic findings, and the differential diagnosis is discussed.

Non-mydriatic fundus photography: a viable alternative to fundoscopy for identification of diabetic retinopathy in an Aboriginal population in rural Western Australia?

PURPOSE

To evaluate the Canon CR5-45NM non-mydriatic fundus camera (Canon, Kanagawa, Japan) for identifying retinopathy and the need for laser treatment in a population of Aboriginal patients with diabetes mellitus in rural Western Australia.

METHODS

Diabetic Aboriginal patients were photographed through undilated pupils using a Canon CR5-45NM non-mydriatic fundus camera, after which ophthalmoscopy was performed using indirect ophthalmoscopy through dilated pupils. The examining ophthalmologist recorded the presence of retinopathy and the need for laser treatment. A proportion of patients were rephotographed through dilated pupils. Photographs were reviewed by a second ophthalmologist who evaluated the quality of the image, the presence of retinopathy and the need for laser treatment. Results of fundus photographs and ophthalmoscopy were compared.

RESULTS

Three hundred and twenty-eight eyes in 164 Aboriginal patients were examined. The mean patient age was 48.2 years (range 16-81 years) and the mean duration of diabetes was 7.5 years (range 1-35 years). Seventy-four eyes (22.6%) were diagnosed with retinopathy using combined examination techniques, 44 (59.5%) of which were identified by ophthalmoscopy and 55 (74.3%) by photography. Thirty-five eyes were deemed to need treatment, 18 (51.4%) of which were identified by ophthalmoscopy and 30 (85.7%) by photography. Kappa coefficient measurement for agreement for presence of retinopathy and need for referral was 0.41 and 0.53, respectively. Photograph quality was significantly improved following pupil dilation.

CONCLUSIONS

The Canon CR5-45NM non-mydriatic fundus camera was relatively good at identifying diabetic retinopathy and could usefully be applied within a screening programme for treatable disease within this population.

Peritoneal membrane transport function in children receiving long-term dialysis

Accurate characterization of peritoneal solute transport capacity in children has been hampered by a lack of standardized test mechanics and small patient numbers. A standardized peritoneal equilibration test was used to study 95 pediatric patients (mean age, 9.9 +/- 5.6 yr) receiving chronic peritoneal dialysis at 14 centers. Patients were divided into four age groups (< 1, 1 to 3, 4 to 11, 12 to 19 yr) for analysis. Each patient received a 4-h peritoneal equilibration test with an exchange volume of 1100 mL/m2 per body surface area. Dialysate to plasma (D/P) ratios for creatinine (C) and urea (U) and the ratio of dialysate glucose (G) to initial dialysate glucose concentration (D/D0) were determined. Mass transfer area coefficients (MTAC) were calculated for the three solutes and potassium (P). The mean (+/- SD) 4-h D/P ratios for C and U were 0.64 +/- 0.13 and 0.82 +/- 0.09, respectively. The mean 4-h D/D0 for G was 0.33 +/- 0.10. D/P and D/D0 ratio results were similar across age groups. Normalized (for body surface area) mean MTAC (+/- SD) values were as follows: C, 10.66 +/- 3.74; G, 12.93 +/- 5.02; U, 18.43 +/- 4.02; and P, 14.02 +/- 3.94. Whereas a comparison of the normalized MTAC values across age groups with an analysis of variance showed significant age group differences only for glucose (P = 0.001) and potassium (P = 0.036), analysis by quadratic regression demonstrated a nonlinear decrease with age for C (P = 0.016), G (P < 0.001), and P (P = 0.034). In summary, evaluation of D/P and D/D0 ratios obtained from a large group of children in a standardized manner reveals values that are similar across the pediatric age range and not unlike the results obtained in adults. In contrast, normalized MTAC values of young children are greater than the values of older children, possibly as a result of maturational changes in the peritoneal membrane or differences in the effective peritoneal membrane surface area.

Ultrasound findings in juvenile nephronophthisis

The ultrasound finding of renal medullary cysts associated with increased echogenicity has been suggested to be diagnostic of juvenile nephronophthisis. The lack of cysts in several of our patients with juvenile nephronophthisis lead us to review the ultrasound findings at presentation in our patient population. Of 11 children with the diagnosis of juvenile nephronophthisis, 10 demonstrated increased echogenicity with loss of corticomedullary differentiation on initial ultrasound. Only 2 children had a single cyst each. On follow-up ultrasound, 2, 4.5, and 7 years later, 3 patients developed visible renal cysts. We conclude that at presentation the ultrasound finding consistent with the diagnosis of juvenile nephronophthisis is most often that of hyperechogenic kidneys without cysts; namely the lack of cysts does not rule out the diagnosis of juvenile nephronophthisis.

The relationship between intraperitoneal volume and solute transport in pediatric patients. Pediatric Peritoneal Dialysis Study Consortium

A multicenter study was conducted to determine the relationship between intraperitoneal volume and solute (e.g., urea, creatinine) transport as determined by the dialysate to plasma (D/P) ratio and mass transfer area coefficient (MTAC). Two 4-h peritoneal equilibration tests were conducted on each of 12 pediatric peritoneal dialysis patients (mean age, 10.8 yr; range, 0.2 to 19.2 yr). One test exchange volume was 900 mL/m2 body surface area (BSA), and the other was 1,100 mL/m2 BSA. Dialysate samples were collected at 0, 30, 60, 120, 180, and 240 min. Blood samples were drawn at 0 and 240 min. Solute equilibration was significantly more rapid with the 900 mL/m2 BSA exchange volume than with the 1,100 mL/m2 exchange volume when evaluated by the D/P ratio. In contrast, no differences in solute transport were noted with either exchange volume when assessed with the MTAC. In conclusion, solute D/P ratios vary with changes in the intraperitoneal volume, necessitating the use of a standardized exchange volume for the reliable interpretation of evaluations such as the peritoneal equilibration tests. In contrast, the use of the MTAC allows for an accurate assessment of solute transport over a wide range of exchange volumes.

Renal replacement therapy after repair of congenital heart disease in children. A comparison of hemofiltration and peritoneal dialysis

The development of renal failure necessitating peritoneal dialysis after cardiac operations is associated with a reported mortality greater than 50%. Improved fluid removal and nutritional support have been reported with the use of continuous arteriovenous hemofiltration and continuous venovenous hemofiltration techniques. We have compared our experience with all three techniques in managing children who required renal replacement therapy after cardiac operations in terms of efficacy (fluid removal, calorie intake, and clearance of urea and creatinine), complications, and outcome. Over a 5-year period renal replacement therapy was initiated in 42 children, and in 34 of them it was successfully established for more than a 24-hour period: 17 were managed with peritoneal dialysis, 8 with continuous arteriovenous hemofiltration, and 9 with continuous venovenous hemofiltration. A net negative fluid balance was achieved in only 6 (35%) patients treated with peritoneal dialysis compared with 50% of those treated with continuous venovenous hemofiltration and 89% of those treated with continuous venovenous hemofiltration. In terms of nutritional support, calorie intake increased by 43% after peritoneal dialysis was started compared with 515% and 409% in the arteriovenous and venovenous hemofiltration groups, respectively, (p < 0.005). The serum urea levels fell by 36% (p = 0.02) and 39% (p = 0.005) compared with pre-therapy levels with arteriovenous and venovenous hemofiltration, respectively, and the creatinine content was reduced by 19% and 33% (p = 0.003). Neither parameter was reduced in the peritoneal dialysis group. We conclude that the use of hemofiltration as a renal replacement therapy after surgical correction of congenital heart disease offers significant advantages over the more traditional approach of peritoneal dialysis. In addition, we suggest that a more aggressive approach to the management of fluid overload and nutritional depletion with hemofiltration may result in a decrease in the very high mortality seen in renal failure after cardiac operations.

Continuous arteriovenous hemofiltration after cardiac operations in infants and children

Acute renal insufficiency after cardiopulmonary bypass can lead to a significant morbidity from fluid overload and electrolyte disturbance, impede pulmonary gas exchange, and postpone weaning from mechanical ventilation. The limitations placed on free water intake result in severe restriction of nutrition while diuretic therapy causes electrolyte imbalance. Artificial renal support either in the form of peritoneal dialysis or hemodialysis may be complicated by sepsis and hemodynamic instability. We reviewed our experience with the use of continuous arteriovenous hemofiltration, an extracorporeal technique for removal of solutes, toxins, and water in critically ill patients with cardiac failure complicated by acute renal insufficiency and hemodynamic instability after cardiopulmonary bypass. Ten infants and children with renal insufficiency caused by low cardiac output had continuous arteriovenous hemofiltration instituted for indications including sepsis, volume overload, oliguria for more than 24 hours nonresponsive to diuretic therapy, and the need for hyperalimentation. All were supported by mechanical ventilation and receiving high-dose inotropic support. Arterial and venous vascular access was successfully obtained by cannulation of the femoral artery and vein in nine patients. Anticoagulation of the circuit was achieved with heparin infusion (6 to 20 micrograms/kg/hr) and monitored by measurement of activated clotting time. The continuous arteriovenous hemofiltration circuit was replaced if there was clot formation, or at 3 days after placement. Dialysis solution (Dianeal) 1.5% or 0.5% was infused as prefilter dilution. With the use of continuous arteriovenous hemofiltration, 20 to 100 m/hr of ultrafiltrate was removed, which allowed correction of hypervolemia, and caloric intake increased from 13.5 kcal/kg/day to 79.5 kcal/kg/day. Continuous arteriovenous hemofiltration was maintained between 5 hours and 8 days and was well tolerated in all patients. Serum urea and creatinine levels declined during continuous arteriovenous hemofiltration. We conclude that continuous arteriovenous hemofiltration is a safe and effective method for fluid and electrolyte homeostasis and that it thus allows hyperalimentation in infants and children after cardiac operations.

Iphosphamide-induced nephrotoxicity in children

The nephrotoxic potential of iphosphamide was evaluated in a retrospective analysis of all children receiving the drug at The Hospital for Sick Children in Toronto. The 25 children exhibiting nephrotoxicity did not receive more cycles or higher doses per square metre than the 78 with normal renal function. Similarly, the two groups received comparable doses and number of cycles of sodium 2-mercaptoethanesulphonate, and had similar rates of exposure to nephrotoxic drugs (except for cis-platinum). Children exhibiting nephrotoxicity were significantly younger (78.1 +/- 64.1 months) than those having normal kidney function (103.8 +/- 66.6 months) (P less than 0.05). Children exhibiting nephrotoxicity were more likely to have received cis-platinum prior to the iphosphamide (10/25, 40%) than those with normal renal function (14/73, 18%) (P less than 0.05). Nephrotoxicity was associated with a significant effect on growth. Careful follow-up of renal function should take place in children receiving iphosphamide, with special attention paid to children younger than 5 years of age and those who have received cis-platinum.

Personalized versus usual care of previously uncontrolled hypertensive patients: an exploratory analysis

This study was conducted to explore whether the quality of provider care may contribute to blood pressure reduction and whether other factors related to the treatment of hypertension may explain decline in blood pressure. In the study, 46 uncontrolled (greater than or equal to 140/90 mm Hg), medically treated hypertensive patients who received more personalized care differed significantly in the magnitude of blood pressure reduction from 36 usual-care patients (10/7 vs 2/2 mm Hg means for systolic and diastolic blood pressure reduction, respectively). About twice as many experimental patients as controls were reclassified as having "controlled" blood pressure, and this difference reached statistical significance. A multiple regression analysis for personalized-care subjects showed that no dynamic variables were related to blood pressure changes. It was postulated that more personalized care may have accounted for the significant difference between groups in blood pressure reduction. Similar personalized monitoring services might be important additions to usual medical care in order to control blood pressure more fully in high-risk hypertensive patients.

Minimal lesion disease followed by membranous glomerulonephropathy in two children with nephrotic syndrome

Two children with nephrotic syndrome are described whose clinical course, initial response to steroids, and renal biopsies were consistent with a diagnosis of minimal lesion disease (MLD). Both children subsequently became resistant to steroids and repeat renal biopsies 7 and 8 years after initial biopsies showed membranous glomerulonephropathy (MGN). Explanations are suggested which may account for the occurrence of MLD followed by MGN in a single patient. These cases illustrate the necessity of performing repeat renal biopsies in patients with nephrotic syndrome if the clinical behavior and response to steroids are not typical for MLD.

Nephrotic syndrome and diffuse mesangial proliferative glomerulonephritis in children

The clinical course, response to therapy, and outcome were analyzed in 25 children with nephrotic syndrome associated with moderate to severe mesangial cell proliferation. The conditions of more than two thirds of the patients (16/23) failed to respond to prednisone therapy, and renal insufficiency or failure developed in 13. Our data suggest an association between response to therapy and degree of mesangial cell proliferation. Persistent nephrotic syndrome was associated with slow deterioration of renal function.

Evaluation of an educational program on compliance with medication regimens in pediatric patients with renal transplants

An educational program was initiated in an attempt to improve compliance in taking medications among pediatric renal transplant patients. Compliance was assessed by pill counts and by knowledge about medications by interview and questionnaire before, during, and after a six-month study period. Forty-three percent of the population was initially found to be in some way noncompliant with medication regimens, and 19% remained so after extensive counseling and instruction. Factors associated with noncompliance were adolescence, female sex, and family instability. Compliance was associated with direct parental involvement and voluntary maintenance of medication calendars. Although knowledge about drugs significantly improved, there was no correlation with compliance; motivational factors appeared to be of greater importance.