PubMed HealthSearch

Biomedical subjects

R Vanholder

Publications and source records attributed to R Vanholder.

10 recordsLinked to original sources

A longitudinal, five year survey of urea kinetic parameters in CAPD patients.

This study reports on the five years' evolution of the KT/V urea index and protein catabolic rate (PCR) in 16 CAPD patients who were treated with a constant daily dialysis dose. Total KT/V urea index decreased with time from a value of 0.96 +/- 0.06 at the start to 0.55 +/- 0.05 at five years of treatment. This decline was due to the opposite changes of two important parameters affecting the index. First, the contribution of the residual urinary KT/V gradually decreased from 28.6% at the start to 8 to 9% after four years. Second, the distribution volume of urea calculated as a constant fraction of body weight gradually increased. The body weight increased from 58.2 +/- 2.79 kg at start to 70.6 +/- 3.33 kg at five years. Peritoneal urea clearances and ultrafiltration rates remained stable. In 12 patients with stable body weight between 24 and 48 months, PCR decreased from 0.98 +/- 0.05 to 0.87 +/- 0.05 g/kg/day. A positive correlation between KT/V urea and PCR and a negative correlation between KT/V urea and number of hospitalization days, peritonitis rates and peripheral nerve conductivity was found. The same negative correlation was found when only the KT/V urea index obtained during the first year of treatment was considered. In conclusion, the KT/V urea index decreases in CAPD patients primarily because residual renal function decreases and body weight increases, while the peritoneal clearing for urea is maintained. The index correlates with some clinical parameters, and may have some prognostic value.

Adult

Endotoxin transfer through dialysis membranes: small- versus large-pore membranes.

In this in-vivo study, dialysate and serum endotoxin was evaluated before and after haemodialysis with small-pore (PS400) and large-pore (PS600) polysulphone dialysers, and before and after haemodiafiltration with the PS600 filter. The source of the endotoxin was the presence in dialysate of Pseudomonads at a concentration of 10(3)-10(4) CFU/ml. Endotoxin was measured by a modified chromogenic limulus amoebocyte lysate (LAL) assay. In spite of dialysate endotoxin concentrations greater than 100 pg/ml, no changes in pre- versus posttreatment LAL reactivity were observed in PS400 dialysis and PS600 haemodiafiltration. In contrast, PS600 haemodialysis was related to an increase in serum LAL reactivity from 1.3 +/- 1.5 to 3.8 +/- 2.0 pg/ml (n = 15, P less than 0.01), and five patients (33.3%) showed a post-dialysis value in excess of 5 pg/ml. Our data are consistent with the absence of in-vivo endotoxin transfer during haemodialysis with small-pore dialyser membranes, and during haemodiafiltration with membranes with larger pores. An increase in LAL reactivity during haemodialysis with membranes with larger pores is, however, present, presumably due to the occurrence of backdiffusion/filtration with that specific strategy.

Diffusion

Pain at the injection site of subcutaneously administered erythropoietin in maintenance hemodialysis patients: a comparison of two brands of erythropoietin.

Local pain due to subcutaneous erythropoietin (EPO) injection into the thigh was studied using a verbal score ranging from 0 to 4. Equivoluminous doses of epoetin-alpha (Cilag) and epoetin-beta (Boehringer) were compared in 2 controlled single-blind experiments: 10 dialysis patients were treated at random for 4 weeks at consecutive sessions with both brands of EPO, and 40 patients were treated in 1 session only with the 2 brands simultaneously. Pain scores were 1.12 +/- 0.28 versus 0.15 +/- 0.06 (p less than 0.05) and 1.75 +/- 0.19 versus 0.08 +/- 0.04 for epoetin-alpha and epoetin-beta, respectively (p less than 0.001). Treatment acceptance was 48% for epoetin-alpha versus 83% for epoetin-beta (p less than 0.05).

Aged

Polymorphonuclear cell function and infection in dialysis.

End-stage renal disease is characterized by enhanced susceptibility for infectious diseases, carrying an important risk of morbidity and mortality. In the host's defense against bacterial infection, a central role is played by phagocytic ingestion of bacteria, followed by their destruction after metabolic production of oxygen free radical species. Our studies have concentrated on the energy delivery by the hexose monophosphate shunt (HMS) to NAD(P)H-oxidase, the enzyme responsible for free radical production. This evaluation was realized by measuring, in whole blood, the CO2 produced from standard quantities of radiolabeled glucose, with data normalized for the number of polymorphs in each sample. Our studies indicate that: (1) glycolysis is disturbed in uremic outpatients from a SCrea of 6 mg/dl and a CCr of 15 ml/min; (2) similar functional disturbances are found in pre-dialysis blood samples of hemodialyzed patients; (3) this functional disturbance is further intensified during dialysis with cuprophan, which is not the case for non-complement activating dialyzers; (4) the response is especially suppressed towards Staphylococcus Aureus, the bacterial species responsible for the majority of infections in uremia; (5) that functional disturbances are mainly related to uremic toxicity, dialyzer membrane bio(in)compatibility, and uremic anemia. Biochemical disturbances in PMNL, induced by a multifactorial patho-physiologic process, may therefore be related to the enhanced incidence of infection in uremic patients.

Glycolysis

The effect of adding Br or Zn supplements to the dialysate on the concentrations of Br and Zn in the blood of hemodialysed patients.

The effect of adding Br or Zn supplementation to the dialysate on the concentrations of Br and Zn in the blood of hemodialysed patients, is investigated. Patients with end-stage renal failure on hemodialysis show an abnormal trace element pattern. Our patients showed lowered serum Br and Zn concentrations. Four patients were subjected to dialysates with varying Br content. The impact on their serum and packed cells concentrations was evaluated. The supplementation resulted in an increase in the concentrations in serum and in packed cells. The Br concentration in serum and packed cells closely followed the dialysate content. In order to restore the Zn concentration to the normal level a ZnCl2 solution was added to the dialysate of 4 other patients. Zn accumulated in the patient as a consequence of its diffusion against the concentration gradient.

Bromine

Reye's syndrome in an adult.

Reye's syndrome or encephalopathy with fatty infiltration of the liver occurs mainly in childhood and to a lesser degree in adult age. This report concerns a rare adult case of this syndrome in Europe. The different diagnostic steps are described, with special emphasis on the enzymatic disturbances of the Krebs-Henseleit cycle and on the morphological criteria needed to confirm the diagnosis.

Adult