Inherited renal tubulopathies associated with metabolic alkalosis: effects on blood pressure.

Inherited tubular disorders associated with metabolic alkalosis are caused by several gene mutations encoding different tubular transporters responsible for NaCl renal handling. Body volume and renin-angiotensin-aldosterone system status are determined by NaCl reabsorption in the distal nephron. Two common hallmarks in affected individuals: hypokalemia and normal / high blood pressure, support the differential diagnosis.

Essential fatty acid deficiency profile in patients with nephrotic-range proteinuria.

Plasma free fatty acids are bound to albumin, filtered through the glomeruli, and reabsorbed at the proximal nephron. The aim of the present investigation was to determine if urinary loss of fatty acids results in essential fatty acid (EFA) deficiency in patients with nephrotic-range proteinuria. We studied 12 patients aged 9 months to 23 years (eight male, four female) four suffering from congenital nephrotic syndrome (NS) and eight from different renal diseases.

Osteogenesis imperfecta: anthropometric, skeletal and mineral metabolic effects of long-term intravenous pamidronate therapy.

Background: Administration of bisphosphonates represents a beneficial therapy in children and adolescents with severe osteogenesis imperfecta (OI) because it significantly reduces the annual rate of bone fractures.

Aim: To evaluate the anthropometric, skeletal and mineral metabolic effects of long-term intravenous pamidronate therapy in OI.

Methods: Ten patients, aged 5 mo to 25 y, with OI received cyclical intravenous pamidronate.

Fatty acid composition of skeletal muscle and adipose tissue in Spanish infants and children.

There is a relationship between the fatty acid profile in skeletal muscle phospholipids and peripheral resistance to insulin in adults, but similar data have not been reported in infancy and childhood. The objective of this study was to investigate the fatty acid composition of skeletal muscle and adipose tissue across the paediatric age range. The fatty acid profile of skeletal muscle phospholipids and adipose tissue triacylglycerols was analysed in ninety-three healthy Spanish infants and children distributed into four groups: group 1 (0 to <2 years, n 10); group 2 (2 to <5 years, n 41); group 3 (5 to <10 years, n 24); group 4 (10 to 15 years, n 18).

Abnormalities in plasma fatty acid composition in human immunodeficiency virus-infected children treated with protease inhibitors.

Aim: To study plasma fatty acid composition in human immunodeficiency virus-infected children treated with protease inhibitors and its relation with other components of the metabolic syndrome observed after this therapy.

Design: Cross-sectional study from collected clinical database.

Subjects: 17 children with HIV infection treated with protease inhibitors.

Bone mineral density and bone turnover in patients with Bartter syndrome.

The aim of this investigation was to evaluate bone mineral density (BMD), by use of DXA, and bone turnover, in patients with Bartter syndrome (BS). Ten patients (2 with BS type II and 8 with BS type III) were included in the procedure. Age at study varied between 2 and 30 years.

A founder mutation in the CLCNKB gene causes Bartter syndrome type III in Spain.

The term "Bartter syndrome" encompasses a group of closely related inherited tubulopathies characterized by markedly reduced NaCl transport by the distal nephron. At present, five different genetic variants have been demonstrated. The majority of patients with so-called classic Bartter syndrome carry inactivating mutations of the CLCNKB gene encoding the basolateral ClC-Kb chloride channel (Bartter syndrome type III).

Long-term renal follow-up of extremely low birth weight infants.

There is evidence that low birth weight caused by intrauterine growth retardation adversely affects normal renal development. Very little information on this issue is available on children born very prematurely. This investigation examined clinical and functional renal parameters in 40 children (23 boys, 17 girls) ranging in age between 6.

Genetic and metabolic determinants of increased plasma plasminogen activator inhibitor-1 activity in children with renal transplants.

Recent studies have shown that activity of plasminogen activator inhibitor-1 (PAI-1), a prothrombotic protein, may be increased in transplanted patients. The aim of the present investigation was to determine PAI-1 activity in pediatric recipients of renal transplants and to establish the relative contribution of both genetic and metabolic factors. In 29 children and adolescents with stable renal transplants, we related plasma PAI-1 activity to an indicator of inflammatory status [plasma concentration of C-reactive protein (CRP)] and to elements of the insulin resistance syndrome [body mass index (BMI), fasting insulinemia, HOMA index and plasma triglyceride, HDL-cholesterol, apolipoproteins A-1 and B concentrations].

Hyperhomocysteinemia in children with renal transplants.

Many studies have demonstrated a strong association between elevated plasma total homocysteine (tHcys) levels and vascular disease. The aim of the present study was to determine the plasma levels of tHcys in pediatric recipients of renal transplants, to establish possible correlations with renal function, lipid profile, and folate and vitamin B12 status, and to assess whether the C677T and A1298C polymorphisms in the 5, l0-methylenetetrahydrofolate reductase (MTHFR) gene were associated with a particular risk. A total of 26 transplanted children and adolescents were investigated.

Familial hypercalcemia and hypercalciuria: no mutations in the Ca2+-sensing receptor gene.

A 6-year-old boy presented with persistent hypercalcemia, hypercalciuria and nephrocalcinosis from early infancy. His 40-year-old father also had hypercalcemia and hypercalciuria. In both individuals serum values of intact parathyroid hormone (PTH) were repeatedly normal.

Branchio-oto-renal syndrome: identification of a novel mutation in the EYA1 gene.

Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by the association of branchial cysts or fistulae, external ear malformation and/or preauricular pits, hearing loss, and renal anomalies. Mutations in the EYA1 gene, a human homologue of the Drosophila 'eyes absent' gene, have been identified as cause of the syndrome. We report here two families with BOR syndrome.

Predictors of final adult height after renal transplantation during childhood: a single-center study.

Aim: Assessment of final adult height and its predictive factors in children transplanted (RTx) and followed up in a single center.

Methods: A cohort of 32 patients (17 boys, 15 girls) who received RTx before the age of 15 years and had reached a final adult height was selected. Twenty patients received a single RTx, 9 patients received two RTx, and 3 patients received three RTx.

Antibodies to gliadin, endomysium, and tissue transglutaminase for the diagnosis of celiac disease.

Background: Tissue transglutaminase has recently been identified as the main autoantigen recognized by antiendomysial antibodies in celiac disease. Serum immunoglobulin (Ig)A antibodies to tissue transglutaminase (tTG-ab) determined by an enzyme-linked immunosorbent assay (ELISA) technique have been reported to correlate closely with IgA antiendomysial antibodies (EMA). The purpose of this study was to assess the sensitivity, specificity, and predictive value of tTG-ab measured by a commercially available ELISA technique, compared with those of EMA and IgA antigliadin antibodies (AGA) for the diagnosis of celiac disease.

Bartter and related syndromes: the puzzle is almost solved.

It is now evident that the term Bartter syndrome does not represent a unique entity but encompasses a variety of disorders of renal electrolyte transport. Application of molecular biology techniques has permitted a better understanding of these "Bartter-like syndromes," which at present can be divided into three different genetic and clinical entities. Neonatal Bartter syndrome is observed in newborn infants and characterized by polyhydramnios, premature delivery, life-threatening episodes of fever and dehydration during the early weeks of life, growth retardation, hypercalciuria, and early-onset nephrocalcinosis.

Renal magnesium handling in infants and children.

Renal handling of magnesium (Mg) has been incompletely studied during infancy and childhood due to the difficulty, until recently, of measuring the diffusible fraction of plasma Mg. In the present investigation this methodology has been used to assess Mg homeostasis in 45 healthy infants, aged 1 to 12 months, and in 63 healthy children, aged 1 to 15 years. When compared to children, infants had significantly higher plasma values (mean +/- SD) for both total (0.

Potassium homeostasis and its disturbances in children.

Although only 2% of the body potassium is present in the extracellular space, its concentration is finely regulated by the internal balance, or distribution of potassium between the intracellular and extracellular compartments, and by the external balance, or difference between intake and output of potassium. Internal balance is modulated by a host of factors, including insulin, epinephrine, extracellular pH and plasma tonicity. Potassium output from the body is mainly determined by renal excretion.