Effect of on-line conductivity plasma ultrafiltrate kinetic modeling on cardiovascular stability of hemodialysis patients.

The aim of this multicenter, prospective, randomized cross-over study was to clarify whether on-line conductivity ultrafiltrate kinetic modeling (treatment B), as a substitute for sodium kinetic modeling, is capable of reducing intradialytic cardiovascular instability in comparison with standard treatment (treatment A), by reducing the sodium balance variability. Both treatments were performed by means of a modified hemodiafiltration technique. Treatment A was performed using fixed dialysate conductivity; treatment B made use of the dialysate conductivity derived from a conductivity kinetic model, in order to obtain an end-dialysis ultrafiltrate conductivity at each dialysis session that was equal to the mean value determined in the same patient during the four-week run-in period.

Treatment of hypertension in chronic renal insufficiency.

Several trials clearly demonstrate the importance of correcting hypertension and proteinuria in slowing chronic renal insufficiency (CRI) progression. The relationship between hypertension and CRI is at least partly the consequence of impaired renal hemodynamics, mainly mediated by the renin-angiotensin system. Two classes of drugs have so far been shown to have an antiproteinuric and renoprotective effect, in addition to their antihypertensive action: ACE inhibitors and calcium-channel blockers (at least the non-dihydropyridines) which also interfere with the actions of angiotensin II.

Factors affecting progression of renal insufficiency.

The aim of this study was to analyze the factors affecting chronic renal insufficiency (CRI) progression at diagnosis (markers of progression), their spontaneous or therapy-induced behavior, and their relationship to CRI progression during follow-up. The underlying disease is the 'determinant factor' of progression and although clinical trials usually report crude cumulative renal survival without taking into account concomitant risk factors, it is known that diabetic nephropathy, polycystic kidney disease, and glomerulonephritis are more progressive than nephroangiosclerosis and interstitial nephropathy. Among the 'effect modifiers,' the baseline level of renal function, hypertension, and proteinuria are the most important.

Hepatitis C virus genotypes in chronic dialysis patients.

Background: Hepatitis C virus (HCV) infection is highly prevalent in dialysis patients. To further characterize HCV infection in this patient population, we studied the distribution of viral genotypes in 55 patients undergoing chronic dialysis treatment with seropositivity for HCV markers.

Methods: Thirty-two of 55 (58%) patients showed HCV RNA in the serum using reverse transcription polymerase chain reaction (RT-PCR) in the 5'-untranslated region (UTR) of the viral genome.

IgM antibody response to hepatitis C virus in end-stage renal disease.

Background: In HBV infection, as in other viral diseases, antibodies of the IgM class are associated with acute or ongoing infection. In contrast, the significance of this antibody in HCV infection is unclear and data regarding end-stage renal disease (ESRD) patients are lacking.

Methods: We tested sera from 78 ESRD patients (66 chronic dialysis patients, 12 renal allograft recipients) showing anti-HCV IgG antibody, for serum anti-HCV IgM core antibody.

Determining the adequacy of sodium balance in hemodialysis using a kinetic model.

The importance of sodium balance avoiding intradialytic cardiovascular instability and interdialytic hypertension and pulmonary edema is well known. An early analytical single-pool kinetic model created to evaluate sodium balance in hemodialysis, using flame photometry to determine plasma and dialysate sodium concentrations, has been shown to have a level of imprecision of +/- 2.8 mEq/l in predicting end-dialysis sodium plasma water concentrations (NaPWt).

Influence of membranes on morbidity.

Haemodialysis, a life-saving treatment extending the life of many people for up to more than 20 years, causes acute complications and symptoms and long-term uraemic complications affecting the patient's morbidity and mortality. These inadequacies have been attributed not only to the dialysate composition but also to the membrane. In evaluating the benefits of biocompatible membranes reported in the literature, we have taken into account nutritional aspects, infections, cardiovascular effects, long-term effects, the potential renoprotective effect and patients with acute renal failure survival.

Virological and histological features of hepatitis C virus (HCV) infection in kidney transplant recipients.

Background: Although there are some reports regarding prevalence of anti-HCV antibodies in kidney transplant patients, there are scarce data about viraemia, genotyping and liver histology of HCV infection in kidney transplant recipients.

Methods: We studied the prevalence of anti-HCV antibodies by second-generation screening and confirmatory assays in a cohort of 73 renal allograft recipients. All patients were tested for serum HCV RNA using reverse transcription polymerase chain reaction in the 5'-untranslated region (UTR) of the viral genome.

Virological characteristics of hepatitis C virus infection in chronic hemodialysis patients: a cross-sectional study.

Detection of hepatitis C virus viremia (HCV RNA) in serum of hemodialysis (HD) patients is crucial for documenting ongoing infection because the clinical and epidemiological importance of anti-HCV positivity is not clear. HCV viremia was studied in 104 HD patients by reverse transcription polymerase chain reaction (RT PCR) using primers localized in the 5' non-coding region of the viral genome. We used two different methods to detect HCV RNA: a direct PCR amplification of HCV RNA from human serum, and a standard RT PCR procedure (requiring the RNA extraction step).

Comparison of second-generation screening and confirmatory assays with recombinant antigens and synthetic peptides against antibodies to hepatitis C virus: a study in renal patients.

The aim of this study was to compare some common tests which are nowadays routinely used to screen and to confirm anti-HCV antibodies in renal patients. There was agreement between Ortho 2 and Abbott 2 in 94% of samples; structural and nonstructural beads of the Abbott supplementary assay were in agreement with 4-RIBA in 98 and in 85% of samples, respectively; 61% of Ortho 2 samples and 65% of Abbott 2 samples were confirmed by 4-RIBA; there was a correlation between semiquantitative analysis of screening tests (Ortho 2 and Abbott 2) and positive results by 4-RIBA; 36 and 33% of Ortho-2- and Abbott-2-positive samples were 4-RIBA indeterminate: in these instances more sophisticated techniques (polymerase chain reaction) (PCR) could be useful as a third-level assay. The comparison between Ortho 2, based on recombinant antigens, and Innotest, based on synthetic peptides, showed agreement only in 44% of samples, but this preliminary comparison cannot afford definitive conclusions.

Hypertension and chronic renal insufficiency: the experience of the Northern Italian Cooperative Study Group.

There is general agreement that hypertension is a prognostic index of the progression of chronic renal insufficiency (CRI), although it remains to be clarified whether this is related to the hypertension per se, or to the underlying disease and the level of CRI. In an attempt to clarify this important point, an inductive analysis was made of the behavior of blood pressure values and their relationship to the progression of CRI in 456 patients (pts) who participated in a multicenter prospective formal randomized trial, designed to compare the effects of a restricted and a controlled protein diet on CRI progression. An analysis was also made (on the population as a whole and by separating the pts into fast progressive and slowly progressive groups) of the type and frequency of the antihypertensive drugs used, the number and type of drugs used in association, and their possible relationship to the progression of CRI.

IgA nephropathy: remission during pregnancy and relapse in the puerperium.

A 39-year-old woman, with proteinuria and microhematuria, at about the 8th week of pregnancy showed a reduction in proteinuria. After the 16th week, proteinuria disappeared. In the 40th week, the patient spontaneously delivered a 1.

The treatment of infected nonunions and segmental defects of the tibia by the methods of Ilizarov.

Circular external fixation using the Ilizarov apparatus combined with internal bone transport or compression-distraction techniques were used to treat 28 patients with infected nonunions or segmental bone loss of the tibia. There were 22 males and six females with an average age of 34 years (range, 17-58 years). Six of 28 patients had infected tibial nonunions associated with hemicircumferential bone loss.

Factors affecting chronic renal failure progression: results from a multicentre trial. The Northern Italian Cooperative Study Group.

In order to evaluate the prognostic factors concerning the rate of progressive deterioration of renal function, we made an inductive analysis of the behaviour of 456 patients in a multicentre, formal prospective trial aimed at clarifying the possible role of protein restriction in retarding the progression of chronic renal insufficiency (CRI). The main clinical and laboratory findings in patients whose plasma creatinine (PCr) levels doubled in comparison with baseline randomization values or who needed dialysis within 24 months after onset of the study were compared with those of the other patients. In addition, independently of the assigned diet, we tested the main variables that might affect CRI progression (sex, systolic and diastolic blood pressure, change in body weight, hematocrit, calcium-phosphate product, proteinuria, protein catabolic rate, total cholesterol and triglycerides).

Lengthening of the forearm by the Ilizarov technique.

The Ilizarov technique was used for lengthening 13 forearms in 12 patients. The different types of treatment were: lengthening of the radius alone, lengthening of the ulna alone with or without radial head relocation, lengthening of one-bone forearms, lengthening of the radius and ulna to the same extent, and differential lengthening of the radius and ulna. The lengthenings ranged from 2 cm to 13 cm (10%-143%).

Lengthening of the humerus using the Ilizarov technique. Description of the method and report of 43 cases.

From 1982 to 1986, 43 humeral lengthenings were performed on 29 patients using the Ilizarov technique. Diagnoses included achondroplasia, old septic arthritis, birth palsy, fracture, congenital shortening, and benign neoplasm. The achondroplastic patients (14) had bilateral lengthenings.

Adequate sodium balance and cardiovascular stability.

To evaluate the sodium balance in haemodialysis and haemodiafiltration a computerised model has been developed, which calculates net sodium balance from the infusive, diffusive, and convective sodium fluxes for each minute of treatment, updating the value of plasma water ionised sodium concentration at each step. Using this model and assuming constant body-weight, treatment time, and net ultrafiltration, different haemodialysis and haemodiafiltration treatments, with different dialysate sodium concentrations, sodium infusions, and pre-treatment plasma water sodium concentrations were simulated. The results show that a less negative sodium balance is almost always obtained during haemodiafiltration than in haemodialysis, when using the same dialysate sodium concentrations.