Hypertension occurs commonly following renal transplantation and may cause end organ damage, such as cardiac hypertrophy. This study seeks to determine which features of hypertension are related to ...cardiac hypertrophy in children after renal transplantation. Ambulatory blood pressure monitoring (ABPM) was performed in 45 pediatric patients, 4.9+/-3.0 years after renal transplantation. ABPM data were related to clinical features and echocardiographic measurements. Hypertension was demonstrated in 33% of patients by casual blood pressure (BP) measurement and in 40% by ABPM. The mean percentage nighttime decline in BP (dipping) was 8.9+/-5.0% for systolic and 13.9+/-7.7% for diastolic BP. Abnormal dipping (<10%) was seen in 58% of patients. BP load (percentage of BP recordings above 95th percentile) was >30% in 44% of patients. Patients taking antihypertensive medication had more abnormal dipping and greater nighttime BP load. The prevalence of left ventricular hypertrophy was 72% before transplantation, 75% after transplantation, and 54% near to ABPM. Left ventricular mass (LVM) indexed to height(3) decreased significantly after transplantation. (40.2+/-14.7 vs. 35.0+/-8.3 g/m(3), P=0.0002). There was no significant relationship between ABPM data and LVM. ABPM was not able to differentiate those patients with persistently elevated LVM. The results suggest that hypertension is not always associated with cardiac hypertrophy following pediatric renal transplantation.
Autosomal recessive polycystic kidney disease (ARPKD) is a relatively common form of pediatric polycystic kidney disease with an incidence of 1:20,000 live births. Previous reports, primarily from ...populations of European origin, indicate that the clinical presentation and disease course are quite variable. Using a retrospective study design, we sought to determine whether the clinical course and outcome of our multi-ethnic patient cohort differs from the published literature. A 10-year (1990-2000) retrospective study was conducted in which we reviewed the clinical, histopathological, and imaging records of our 31 ARPKD patients. Patients were diagnosed between 0 and 14 years of age, with 17 (55%) presenting within the 1st month of life. The mean follow-up was 67 months and age at last follow-up ranged from 0.5 to 16 years. Of the 17 patients diagnosed as neonates, 11 (65%) had respiratory insufficiency complicated by pneumothoraces. Two died shortly after birth and 2 died within the 1st year of life due to respiratory failure. Among the 13 neonatal survivors, 7 (54%) developed progressive renal insufficiency, whereas 6 of 14 (43%) of those children who presented beyond 1 month of age developed renal insufficiency. Hypertension was present in 55% of our patients, with nearly all neonatal survivors requiring antihypertensive management. Evidence of portal hypertension was found in 10 (37%) of the 27 patients who survived the 1st year of life. In our multi-ethnic ARPKD cohort, the 1-year survival rate (87%) and the clinical variability are comparable to those previously reported. With the recent identification of the PKHD1 gene, characterization of disease-causing mutations should provide new insights into the molecular basis for this phenotypic variability.
Gastrostomy tube (g-tube) feeding is recognized to improve the nutritional delivery to children with end-stage renal disease. A retrospective study was undertaken assessing the complications of ...g-tube feeding in children receiving peritoneal dialysis (PD). Twenty-three patients, mean age 3.8+/-3.2 years received PD and g-tube feeding for 758 patient-months, with 127 patients receiving PD for 1,969 patient-months used as controls. Peritonitis occurred every 18.4 patient-months in controls and 7.8 patient-months in those with a g-tube. Peritonitis occurred every 6.0 patient-months before and 8.1 patient-months after g-tube insertion in those undergoing g-tube insertion on PD. PD catheter exit site infection (PDESI) occurred every 18.7 patient-months in controls and 16.8 patient-months in those with a g-tube. PDESI occurred every 126 patient-months before and 16.2 patient-months following g-tube insertion. PD catheter replacement secondary to infection occurred every 109.4 patient-months in controls and 39.9 patient-months in those with a g-tube. It did not occur before g-tube insertion and occurred every 32.5 patient-months following insertion. Thirty-four episodes of g-tube exit site infection occurred, in 10 the same organism caused concurrent peritonitis. G-tube replacement occurred on 37 occasions. Hemodynamically significant gastrointestinal bleeding occurred in 3 patients, being terminal in 1. We conclude that, although not without risk, g-tube feeding in patients receiving PD is not contraindicated.
Apparent mineralocorticoid excess (AME) is a genetic disorder causing pre- and postnatal growth failure, juvenile hypertension, hypokalemic metabolic alkalosis, and hyporeninemic hypoaldosteronism ...due to a deficiency of 11 beta-hydroxysteroid dehydrogenase type 2 enzyme activity (11 beta HSD2). The 11 beta HSD2 enzyme is responsible for the conversion of cortisol to the inactive metabolite cortisone and therefore protects the mineralocorticoid receptors from cortisol intoxication. Several homozygous mutations are associated with this potentially fatal disease. We have examined the phenotype, biochemical features, and genotype of 14 patients with AME. All of the patients had characteristic signs of a severe 11 beta HSD2 defect. Birth weights were significantly lower than those of their unaffected sibs. The patients were short, underweight, and hypertensive for age. Variable damage of one or more organs (kidneys, retina, heart, and central nervous system) was found in all of the patients except one. The follow-up studies of end-organ damage after 2-13 yr of treatment in six patients demonstrated significant improvement in all patients. The urinary metabolites of cortisol demonstrated an abnormal ratio with predominance of cortisol metabolites, i.e. tetrahydrocortisol plus 5 alpha-tetrahydrocortisol/tetrahydrocortisone was 6.7-33, whereas the normal ratio is 1.0. Infusion of 11-3Hcortisol resulted in little release of tritiated water, indicating the failure of the conversion of cortisol to cortisone. Thirteen mutations in the HSD11B2 gene have been previously published, and we report three new genetic mutations in two patients, one of whom was previously unreported. All of the patients had homozygous defects except one, who was a compound heterozygote. Our first case had one of the most severe mutations, resulting in the truncation of the enzyme 11 beta HSD2, and died at the age of 16 yr while receiving treatment. Three patients with identical homozygous mutations from different families had varying degrees of severity of clinical and biochemical features. Due to the small number of patients with identical mutations, it is difficult to correlate genotype with phenotype. In some cases, early and vigilant treatment of AME patients may prevent or improve the morbidity and mortality of end-organ damage such as renal or cardiovascular damage and retinopathy. The outcome of treatment in more patients may establish the efficacy of treatment.
We report an association of renal tubular acidosis (RTA) in two children with glucose-galactose malabsorption (GGM), who were found to have nephrocalcinosis. Although GGM has been reported previously ...with nephrocalcinosis, this report is the first to show that renal tubular acidosis could explain the coexistence of nephrocalcinosis in patients with glucose galactose malabsorption.
Four deleterious mutations are described in the gene for HSD11B2, which encodes the type 2 isoenzyme of 11 beta-hydroxysteroid dehydrogenase (11 beta HSD2). In seven families with one or more members ...affected by apparent mineralocorticoid excess, this disorder is shown to be the result of a deficiency in 11 beta HSD2. Surprisingly, the patients are all homozygous for their mutation. This results from consanguinity in two families and possibly from endogamy or a founder effect in four of the other five families. The absence of compound heterozygotes remains to be investigated.
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