Maternal heterodisomy/isodisomy and paternal supernumerary ring of chromosome 7 in a child with Silver-Russell syndrome.

Silver-Russell syndrome (SRS) is clinically variable although most cases have several common signs. Different chromosomes and chromosomal regions have been associated with SRS. Maternal uniparental disomy (UPD) of chromosome 7 is responsible for 5-10% of cases, probably because of an imbalance between maternal and paternal imprinted genes and more recently maternal duplication or epimutations in the 11p15 imprinted region have been described.

Diagnostic value of colour Doppler twinkling artefact in sites negative for stones on B mode renal sonography.

The aim of the study was to investigate the diagnostic value of the colour Doppler twinkling artefact (TA) in renal stone disease. To enhance the evidence of TA, a preliminary in vitro study was performed to optimise the setting of colour Doppler sonography. In the in vitro study, an oxen kidney was examined using an high-frequency (12.

Effect of potential renal acid load of foods on urinary citrate excretion in calcium renal stone formers.

The aim of this study was to investigate the influence of the potential renal acid load (PRAL) of the diet on the urinary risk factors for renal stone formation. The present series comprises 187 consecutive renal calcium stone patients (114 males, 73 females) who were studied in our stone clinic. Each patient was subjected to an investigation including a 24-h dietary record and 24-h urine sample taken over the same period.

Calcium stone disease: a multiform reality.

In calcium renal stones, calcium oxalate and calcium phosphate in various crystal forms and states of hydration can be identified. Calcium oxalate monohydrate (COM) or whewellite and calcium oxalate dihydrate (COD) or weddellite are the commonest constituents of calcium stones. Calcium oxalate stones may be pure or mixed, usually with calcium phosphate or sometimes with uric acid or ammonium urate.

Spurious estimations of sodium removal during CAPD when [Na](+) is measured by Na electrode methodology.

Background: The aim of this study was to investigate the effect of pH and glucose concentration on sodium removal and the dialysate and plasma sodium ratio (D/PNa) as measured by means of a flame photometer (NaF) or direct ion-selective electrode (NaE) in continuous ambulatory peritoneal dialysis (CAPD).

Methods: In vitro, glucose concentration, pH, NaF, and NaE were measured in fresh peritoneal dialysis solutions (PDSs) before and after the addition of glucose or KOH. In vivo, 66 four-hour peritoneal equilibration tests were performed in 35 patients on CAPD using a low pH PDS with a glucose concentration of 3.

Treatment modalities in comparison: when do clinical differences emerge?

Background: Despite technological advances in dialysis equipment and modalities, the survival, morbidity and quality of life of uraemic patients undergoing regular haemodialysis treatment are still severely affected by acute intradialysis and long-term complications, possibly related to the treatment itself. Convective treatment modalities, such as haemodiafiltration and haemofiltration, are thought to be further improvements over standard diffusive haemodialysis. Moreover, several of the pathways activated in patients during dialysis have the potential to produce many side-effects.

GBV-C/HGV infection in end-stage renal disease.

Recently, two independent teams detected presumed hepatitis agents, which were designated HGV and hepatitis GB virus C; they represent a new genus in the family Flaviviridae. The most accurate way to assess the epidemiology of GBV-C/HGV infection remains the combination of RT-PCR and anti-GBV-C/HGV E2 techniques, to detect respectively current and past GBV-C/HGV infection. Preliminary data from blood donors and healthy individuals have shown that GBV-C/HGV is distributed globally and can induce persistent viremia in humans.

On-line monitoring and convective treatment modalities: short-term advantages.

Background: Despite technological advances in dialysis equipment, the morbidity and quality of life of uraemic patients undergoing regular haemodialytic treatment are still severely affected by acute intradialytic complications possibly related to the treatment itself. Cardiovascular instability still affects >30% of dialytic sessions and, although its pathogenesis is multifactorial, dialysate sodium concentration (and, consequently, intradialytic sodium removal) is one of the main factors affecting intradialytic hypotension. Convective treatment modalities and so-called biocompatible membranes increasingly are recognized as improving acute and particularly chronic dialytic complications because a number of the pathways activated in patients during dialysis with 'bioincompatible' membranes have the potential to produce many side effects.

Antiphospholipid (aPL) antibodies in end-stage renal disease.

Data are few and conflicting about the prevalence and risk factors for antiphospholipid (aPL) antibodies in end-stage renal disease (ESRD). We studied the prevalence, risk factors and clinical manifestations of lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) among ESRD patients (chronic hemodialysis (HD) patients and kidney transplant recipients) and blood donors. LA was assessed in a large cohort (n=180) of patients by the activated partial thromboplastin time (aPTT), dilute Russel's viper venom test (dRVVT) and lupus anticoagulant-sensitive aPTT reagent (PTT-LA).

Detectability of cochlear, acoustic nerve and brainstem potentials in a group of 'normal' preterm newborns recorded with insert earphone.

Thirty-four 'normal' preterm newborns were tested at 40 weeks postconceptional age. To separate electromagnetic artifacts from cochlear potentials and subsequent auditory brainstem responses, a test was given using an insert earphone at 90, 70, 50, 30 dB nHL. The detectability of receptor potentials, waves I, III, V, as a function of stimulus intensity is described: at 90 dB nHL exclusively, we could always identify these peaks because of the better morphological distinctiveness of each potential.

Conductivity: on-line monitoring of dialysis adequacy.

Cardiovascular disease and the inadequacy of delivered dialysis are the main factors determining morbidity and mortality in dialysis patients. We have already demonstrated that a conductivity kinetic model makes it possible to match interdialytic sodium loading and intradialytic sodium removal (the main factor determining cardiovascular morbidity) without the need for blood samples and, thus, in routine clinical practice. The aim of the present study was to test the possibility of using the conductivity method also to determine Kt/v without blood or dialysate sampling.

Hepatitis C virus infection and acute or chronic glomerulonephritis: an epidemiological and clinical appraisal.

Background: The relationship between hepatitis C virus (HCV) infection and acute or chronic glomerulonephritis (GN) is not well understood.

Methods: Two hundred and eighty-four patients with biopsy-proven GN and other renal diseases were studied in a multicentre survey performed during the period 1992-1995. Several clinical parameters were collected for each patient at the time of renal biopsy.

On-line assessment of delivered dialysis dose.

Background: The adequacy of the delivered dialysis dose is essential to prevent patient morbidity and mortality. The determination of effective ionic dialysance (D) is easy, non-invasive and inexpensive, and its use instead of effective urea clearance (K) in kinetically determining apparent" urea distribution volume (Vt) is likely to lead to a correct Kt/V, even though the Vt value may be incorrect. The aim of this study was to test the possibility of using the measurement of D to monitor Kt/V on-line during each dialysis treatment.

Biocompatibility in haemodialysis: fact and fiction.

Several of the pro-inflammatory pathways that are activated in patients during dialysis have the potential of producing many side effects. These occur three times a week, accompanying dialysis, and are particularly intense in patients dialysed with so-called 'bioincompatible' membranes. Despite the proven biological superiority of biocompatible membranes, we lack definitive evidence that complement and cell activation three times a week over a period of years is detrimental to patients, because the results of prospective randomized studies are conflicting.

Systemic thrombolysis for acute myocardial infarction in a renal transplant recipient.

This study describes the successful management of an acute myocardial infarction occurring in a renal transplant recipient with thrombolytic therapy. Although primary coronary angioplasty has been addressed as an alternative therapeutic approach, this approach raises concern for angiography-related contrast media renal toxicity. However, pharmacological therapy with thrombolytics is effective and relatively safe and should be considered as the first-choice treatment in today's clinical setting.

Serologic survey for control of hepatitis C in haemodialysis patients: third-generation assays and analysis of costs.

There is little information about the serologic survey for control of hepatitis C by using third-generation assays among chronic haemodialysis (HD) patients, and no analysis of costs has been made to this end. A serologic survey for control of hepatitis C was performed in 190 HD patients attending a single dialysis unit, using second- and third-generation assays. Costs of both serologic surveys were calculated.

Molecular epidemiology of hepatitis C virus infection in dialysis patients.

There are very few data on the molecular biology of hepatitis C virus (HCV) infection in dialysis patients. 101 patients undergoing dialysis treatment in 4 units in the Lombardy, northern Italy, were analyzed by RT-PCR for HCV viremia, by line probe assay technology for HCV genotyping and by a serological analysis for detecting type-specific antibodies. 61 of 101 (60%) patients showed detectable HCV RNA in serum; HCV genotype 2a was dominant (30/53 = 57%), followed by HCV genotype 1b (20/53 = 37%).

Optimization of sodium removal in paired filtration dialysis by single pool sodium and conductivity kinetic models.

Sodium removal is one of the main factors affecting intradialytic cardiovascular stability and interdialytic hypertension, and its removal should therefore be individualized. The aims of this study were: (1) to test the ability of a single-pool variable volume (SPVV) sodium kinetic model (NaKM) to optimize sodium removal in paired filtration dialysis (PFD), and (2) to test a SPVV conductivity kinetic model (CKM) in order to verify whether CKM can be used as an alternative for NaKM in estimating sodium balance. The mean difference between the NaKM-predicted and measured end-PFD plasma water ionized sodium concentrations was 0.

Ionic dialysance as a method for the on-line monitoring of delivered dialysis without blood sampling.

Background: It is well known that the difference between prescribed and delivered dialysis doses greatly affects the morbidity and mortality of dialysed patients. The on-line monitoring of delivered dialysis is therefore of paramount importance. Recently, a conductivity-based method for determining Kt/V on routine basis has been proposed.

Antimicrobial prophylaxis with ceftriaxone in neurosurgical procedures. A prospective study of 100 patients undergoing shunt operations.

Shunt infection is a major complication of shunt implantation, with Staphylococcus epidermidis found in almost 45% of infected shunts. This pathogen produces an extracellular slime that enables it to adhere to implantable devices and resist antibiotic therapy. Antimicrobial prophylaxis can prevent slime production.