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O Toupance

Publications and source records attributed to O Toupance.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Value of renal scintigraphy in the diagnosis of vascular complications of renal transplantation].

Nuclear medicine can make an efficient contribution to the diagnosis and monitoring of renal disease and to the assessment of therapeutic interventions in the field of renal transplantation. The new radio pharmaceutical MAG 3 labelled with 99mTc provides renal imaging of quality in patients with impaired renal function and enables quantitative evaluation of renal function. We report on radionuclide evaluation, with special emphasis on the analysis of the vascular component of the scintigram, in the different clinical situations (i.e. renal failure) that may compromise the outcome of a successful renal transplant.

Acute Kidney Injury↗
PubMed1993

Variations of protein C in uremic hemodialysed patients.

Protein C has been measured by three different assays (antigenic, amidolytic and chronometric) in 27 end-stage renal insufficient patients before and after hemodialysis. Protein C levels have been compared with other coagulation inhibitors (antithrombin III, protein S) and fibrinolytic parameters. Baseline anticoagulant activity of protein C has been found impaired in eight cases whereas other inhibitors were normal. In four cases, both anticoagulant and antigenic levels were low. In one case, amidolytic method could also found a low activity. Hemodialysis leads to an increase of protein C activity and antigen level. Heparinemia after hemodialysis does not interfere with the chronometric measurement of protein C anticoagulant activity. Total protein level, hematocrit, protein S and antithrombin III are also elevated after hemodialysis. Baseline fibrinolytic parameters are normal and remain unchanged after hemodialysis. The clinical relevance of such modifications is discussed.

Adult↗
PubMed1993

Failure of acyclovir to prevent cytomegalovirus infection in renal allograft recipients.

Cytomegalovirus (CMV) is the most common opportunistic pathogen following renal transplantation and remains a major concern in transplantation centers owing to its high morbidity and impact on renal allografts. Pending more effective antiviral drugs, efforts have been directed toward prevention strategies. We conducted a retrospective analysis to evaluate the efficacy of various prophylactic options used at our institution during the period April 1986 to August 1990. All CMV-negative patients with CMV-negative kidneys (D-R-) received screened, CMV-negative blood products (n = 19). CMV-specific immunoglobulins (CMV Ig) were used in 6 patients at increased risk for primary CMV infection and acyclovir was administered to 21 patients at an initial intravenous dose of 5 mg/kg body weight; then oral doses of 800-3200 mg per day were given according to the patients' estimated creatinine clearance. Thirty-two patients did not receive any CMV prophylactic treatment and served as controls. CMV monitoring of the patients during the first 6 months after transplantation showed an overall infection and disease rate of 81% and 38.1%, respectively, in the acyclovir-treated group. Compared with controls, the incidences of infection and disease were higher in the acyclovir-treated patients, with a significant difference for CMV infection (P = 0.002, generalized Wilcoxon test). Only 1 of the 19 D-R- patients presented with CMV infection. CMV Ig-treated patients tended to have less severe disease without any apparent reduction in infection incidence. Given the high rate of infection in patients at risk, we infer that high-dose acyclovir does not prevent CMV infection in our setting of renal transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Acyclovir↗
PubMed1993

Beta 2-microglobulin metabolism in uremic patients who are undergoing dialysis.

Plasma beta 2-microglobulin (beta 2m) is increased in chronically hemodialyzed patients and remains in a steady range once residual diuresis has stopped. Factors controlling such a steady state are unknown. We undertook metabolic studies to define whether plasma beta 2m is regulated by extrarenal proteolysis of the protein or by storage in a captation pool, a condition which may precede beta 2m-derived amyloidogenesis. Seventeen uremic patients on supportive therapy and five healthy controls were enrolled into the 6 to 10 day study. Using trace amounts of 131I-beta 2m and total body counting, half-life was between 2.4 and 8 days. 125I-beta 2m plasma kinetics was more suitable to calculate fractional catabolic rate and synthetic rate. A three compartment model was chosen to calculate turnover parameters in dialysis patients, whereas the regular two compartment model fitted best for healthy controls. beta 2m synthesis rate was increased in uremic patients when compared with controls (4.49 +/- 2.60 vs. 3.68 +/- 1.43 mg/kg/day, NS). The three compartment model did not integrate all the experimental data, since it was possible to calculate a captation compartment which accumulated beta 2m without fast proteolysis. The captation pool was positively correlated with plasma beta 2m concentration and comprised between 23% and 59% of the amount of the beta 2m disappearing from plasma per day. In conclusion, metabolic studies with radioiodinated beta 2m indicate a slight increase in beta 2m synthesis rate in uremic patients on supportive therapy, irrespective of the technique in use. Kinetic analysis requires a model taking into account a storage compartment which is more complex than the three compartment model.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1991

[Treatment of legionellosis with ofloxacin in kidney transplanted patients. Lack of interaction with cyclosporin A].

Seven cases of legionellosis were observed in a series of 81 renal transplant recipients. In the 6 patients with functional graft, pneumonia occurred 17 days on average after the beginning of transplant rejection treatment. The diagnosis was made by bronchoalveolar lavage: the direct immunofluorescence antigen technique was positive in 5 cases and culture in 6 cases. Legionella pneumophila sero-groups 5 and 1 were identified in one and 5 patients respectively. Six of the 7 patients were treated with ofloxacin. This fluoroquinolone was effective in all cases. It was administered as single therapy in 3 patients and did not interfere with ciclosporin A metabolism. Ofloxacin given in mean doses of 400 mg per day adjusted to renal function proved to be a simple, effective and well tolerated treatment of legionellosis in transplant recipients receiving ciclosporin A.

Adult↗
PubMed1990

Early and late occurrences of destructive spondyloarthropathy in haemodialysed patients.

In a series of 100 patients dialysed for 3 months to 17 years destructive spondyloarthropathy was diagnosed in 11 cases. Lower cervical spine was involved in ten and dorsal spine in one. When compared to patients without arthropathy, spinal involvement was associated with longer duration of dialysis and greater prevalence of parathyroidectomy. The patients with destructive spondyloarthropathy were divided into two groups: Group 1, four patients, in whom arthropathy occurred within the first 41 months of dialysis, and Group 2, seven patients, in whom arthropathy occurred after 106 months of dialysis. Group 1 was associated with greater age, chondrocalcinosis (2 of 4), absence of overt osteoarticular bone defects, and absence of carpal-tunnel syndrome. Parathyroidectomy (PTx) was performed in one patient. Amyloidosis was not found in one patient who came to autopsy. Group 2 was associated with presence of shoulder pain (6 of 7), juxtaarticular bone cysts (6 of 7) and CTS (6 of 7), and absence of radiological chondrocalcinosis. PTx was performed in six of seven patients and amyloidosis was found in three. In conclusion, destructive spondyloarthropathy may be seen early in the course of dialysis, apart from general amyloid involvement of accelereted hyperparathyroidism. A specific finding of this study was the discovery of radiological chondrocalcinosis in association with early arthropathy, which is a well-recognised feature in non-uraemic subjects.

Adult↗
PubMed1990

[Continuous hemodialysis with low blood flow and low dialysate flow in the treatment of acute renal insufficiency].

Slow continuous hemodialysis (SCHD) was performed in 9 patients with oliguric acute renal failure and cardiovascular instability. The vascular access was a Scribner's shunt in 7 patients and a double lumen venous catheter with a BSM22 blood system in 2 patients. Three different dialyzers were tested. The mean urea clearance was 10.8 +/- 1.5 ml/min with the 0.2 m2 polysulfone hollow fiber dialyzer, 14.3 +/- 2.7 ml/min with the 0.5 m2 AN 69 S parallel plate dialyzer and 13.8 +/- 1.8 ml/min with the 0.6 m2 AN 69 hollow fiber dialyzer. The mean dialysate flow rate was 15.6 +/- 1.9 ml/min, 15.2 +/- 0.7 ml/min and 15.1 +/- 1.6 ml/min for the three dialyzers, respectively. A linear relationship was documented for blood urea clearance and dialysate flow rate indicating clearly that low blood flow from 60 to 100 ml per min was appropriate for optimal diffusive transfer. The technic required continuous heparin anticoagulation. Three patients died of causes not related to the SCHD technic. When used in critically ill patients, SCHD is a simple method, suitable for intensive care unit staff with no trained dialysis nurses and allows an adequate control of uremia, fluid removal, acid base homeostasis and parenteral nutrition.

Acute Kidney Injury↗
PubMed1989

Serum beta 2 microglobulin and extracellular fluid volume during haemodialysis.

Conflicting results have been published concerning serum beta 2 microglobulin (beta 2-M) kinetics during dialysis with a cuprophane membrane which is not permeable for the protein. We have investigated the hypothesis that the apparent increase of free serum beta 2-M could result from extracellular fluid volume (ECV) contraction. Using inulin, ECV was measured before and 1 h after a dialysis session with a sodium dialysate concentration of 145 mmol/l. Dialysis was performed either with a cuprophane or a high-flux membrane. Transcellular water shift and changes in beta 2-M concentration were calculated from total body water changes (ultrafiltration) and ECV. ECV decreased from a predialysis value of 16.6 +/- 3.51 (mean +/- SD) (24.9% bodyweight) to a postdialysis value of 11.9 +/- 2.11 (19.8% bodyweight). Ultrafiltration was only 3.1 +/- 1.01, indicating concomitant water shift from ECV to intracellular fluid space. A significant decrease in corrected beta 2-M concentration was found for high-flux membranes. However, postdialysis beta 2-M did not change significantly after dialysis with cellulosic membranes. In conclusion, the apparent increase of serum beta 2-M concentration measured during dialysis with cellulosic membranes may be explained by ECV contraction. These results have to be taken into account for any pathogenic mechanism of the beta 2-M-associated amyloidosis occurring in long-term haemodialysed patients.

Amyloidosis↗
PubMed1987

[Magnesium hydroxide treatment of hyperphosphatemia in chronic hemodialysis patients with an aluminum overload].

The control of hyperphosphatemia in dialysis patients is frequently achieved using aluminium hydroxide (A1(OH)3) and/or calcium carbonate (Ca CO3). However, this effect is counterbalanced by risk of aluminium intoxication and hypercalcemia. An alternative to the use of these phosphate binders is the prescription of magnesium hydroxide (Mg(OH)2) in association with a magnesium free dialysate. 19 patients with subtoxic plasma aluminium concentration received such a therapy. 9 months after starting the essay 4 patients had been excluded for digestive intolerance (3 cases) and neuro-psychic symptoms related to hypermagnesemia (1 case) after therapy with maximal doses of 6 to 12 g/d. Plasma inorganic phosphorus was decreased from 2.47 +/- 0.32 to 1.86 +/- 0.40 mmol/l (P less than 0.05) and plasma aluminium from 3.03 +/- 0.93 to 1.52 +/- 0.15 mumol/l (P less than 0.05). The results have been obtained without any significant increase in plasma and red cell magnesium levels. Metabolic alkalosis has been observed in association with the increase of ion exchange resin (sodium polystyrene sulfonate: Kayexalate) to treat progressive hyperkalemia. With the exception of possible metabolic effects occurring on a long term basis, Mg(OH)2 in association with magnesium-free dialysate seems of value to treat dialysis hyperphosphatemia.

Adult↗