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G Deray

Publications and source records attributed to G Deray.

At least 19 recordsLinked to original sources
PubMed2006

Analysis of the optical concentration curve to detect access recirculation.

The optical blood volume curve sometimes presents either a positive or a negative rapid and reversible variation (spike) during the step of the dialysate conductivity, automatically set by the monitor for the ionic dialysance (ID) measurement. We studied whether this feature was in relation with access recirculation. Firstly, we studied if the manoeuvre of reversed position of the blood lines created the same feature in the blood volume curve. Secondly, two medical teams systematically checked for the presence of spikes and measured the access recirculation by way of an ultrasound dilution technique. The manoeuvre of reversed position of the blood lines invariably reproduced the same feature on the curve of the optical blood volume measurement in case of a recirculation greater than 20%. In the normal position of the blood lines, the 16 patients with an access recirculation greater than 20% had spikes. Spikes during ID measurement were not constant for an access recirculation between 10 and 20% and did not occur for an access recirculation of less than 10% or an undetectable one. The special spike of the optical blood volume curve occurring during the ID measurement clearly detects access recirculation. The specificity is of 100% when this modification is present all along the dialysis session for all the ID measurements and the sensitivity is 100% when the access recirculation is greater than 20%.

Arteriovenous Shunt, Surgical↗
PubMed2006

Dialysis and iodinated contrast media.

Contrast media are excreted mainly by glomerular filtration. There is thus, a significant correlation between both body and renal clearances of contrast media and glomerular filtration rate, and their renal excretion will be delayed in patients with renal insufficiency. Contrast media can be efficiently removed from blood by hemodialysis (HD). Since most contrast media are middle-sized molecules, the main factors potentially influencing their removal by HD are blood flow, membrane surface area, molecular size, transmembrane pressure, and dialysis time. Peritoneal dialysis is also effective in removing contrast agents from the body but takes longer than HD. Dialysis immediately after radiographic contrast studies has been suggested for two groups of patients. Those on chronic HD and those at very high risk for contrast nephropathy. Three studies have examined the necessity of immediate dialysis after intravascular injection of contrast media in chronic HD patients; the authors found no evidence that it is effective at preventing contrast nephropathy. The reasons why HD treatment was not beneficial in those three studies are not known. Perhaps, the rapid onset of renal injury after administration of contrast media is one answer. It is also possible that HD per se was nephrotoxic and might have offset the beneficial effect of the removal of contrast media. Marenzi et al. randomized 114 consecutive patients with chronic renal failure undergoing coronary interventions to either hemofiltration in an intensive care unit or isotonic saline hydration. The authors concluded that periprocedural hemofiltration given in an intensive care unit setting appears to be effective in preventing the deterioration of renal function due to contrast agent induced nephropathy and is associated with improved in-hospital and long term outcomes. The concentration of contrast media can effectively be reduced by HD and peritoneal dialysis. HD does not offer any protection against contrast media induced nephrotoxicity. Hemofiltration may decrease the risk of contrast induced nephropathy and have some long-term benefits, but additional studies are needed to better define the appropriate population for this treatment.

Contrast Media↗
PubMed2005

Tuberculosis after conversion from azathioprine to mycophenolate mofetil in a long-term renal transplant recipient.

We report the third case in the literature of a patient with a long-lasting renal allograft who experienced tuberculosis just after the switch from azathioprine to mycophenolate mofetil. The switch was likely responsible for the reactivation of dormant tuberculosis; prophylactic antituberculous treatment should be considered in cases of such a therapeutic change.

Antitubercular Agents↗
PubMed2005

Gastric bypass and resolution of proteinuria in an obese diabetic patient.

There is few human studies evidence that suggest a role for obesity in the formation and progression of glomerular lesions. We report the case of a morbidly obese female with diabetic nephropathy that was subsequently diagnosed with renal failure. Proteinuria resolved after gastric bypass procedure. The reduction of glomerular hyperfiltration and blood pressure associated with the important weight loss may be the major contributors to the decrease of proteinuria and serum creatinine levels in our patient.

Blood Pressure↗
PubMed2005

Is low-dose methotrexate nephrotoxic? Case report and review of the literature.

Methotrexate (MTX) has become the most commonly prescribed disease-modifying anti-rheumatic drug. However, toxicity is an important drawback of MTX therapy and permanent discontinuation of MTX for adverse effects occurs in 1 patient out of 10. Although high-dose MTX is known to be nephrotoxic, data on low-dose MTX renal effects are scanty. We report an insidious and progressive deterioration of renal function during long-term low-dose MTX in a 59-year-old woman. Kidney biopsy revealed advanced kidney fibrosis with extensive interstitial and glomerular fibrosis, and vascular sclerosis. We suggest that patients on low-dose MTX therapy even alone, should be periodically monitored for creatinine levels.

Antirheumatic Agents↗
PubMed2005

[Kidney and glitazones].

PPARgamma nuclear receptors are mainly expressed in adipose tissue. However, they are also expressed in renal glomerular tissue and in vascular walls, thus participating through various and complex mechanisms, to glomerular and vascular sclerosis and to nephropathy development and progression. Studies carried out with glitazones, pharmacological agonists of nuclear receptor PPARgamma, in experimental models, either in vitro, or in vivo in animal models, have demonstrated their favourable effects on arterial blood pressure and on prevention and/or progression of diabetic nephropathy. The few clinical studies conducted in type 2 diabetic patients to assess these effects, are also in favor of a beneficial effect of glitazones on blood pressure and nephropathy in these patients. Thus, it appears extremely important and fully justified to conduct specific studies in patients with type 2 diabetes, with the aim to establish and to better characterize these effects in various clinical conditions (antihypertensive effect in treated hypertensive patients according to the class of antihypertensive agents used, prevention of diabetic nephropathy and/or effect on its progression, renal protection, etc.). Some adverse events, although with a low incidence, may be associated with glitazone use (weight gain, peripheral oedema, fluid retention, etc.), and may limit their use in some patients. It is clearly important to better understand the pathophysiological mechanisms of these effects and their possible long term consequences. Finally, it is important to emphasize the easiness to use glitazones in patients with renal insufficiency, without the need to adjust the drug regimen.

Animals↗
PubMed2005

PPAR-gamma-agonists' renal effects.

PPAR-gamma ligands, including thiazolidinediones, have recently become clinically available for treating insulin-resistant diabetes mellitus. Accumulating evidence suggests that these drugs not only significantly improve insulin sensitivity but also may have antiproteinuric effects in genetically obese diabetic rodents and patients with type II diabetes and diabetic nephropathy. Moreover, troglitazone reduced expression of ECM proteins and transforming growth factor-beta in glomeruli from streptozotocin-induced diabetic rats. Many other properties including antiproteinuric, hemodynamic, and antihypertensive effects in insulin-dependent diabetes mellitus suggest that PPAR-gamma ligands might have a direct, beneficial renal effect, independent of their capacity to improve glucose tolerance. Besides their antidiabetic effects, thiazolidinediones have been shown to lower blood pressure in diabetic patients with hypertension and patients with diabetic nephropathy through multiple mechanisms. Several studies showed the efficacy of PPAR-gamma agonists to ameliorate the progression of glomerulosclerosis. The effect is independent of insulin effects and could only be partially due to lipid effects. These renal protective effects of PPAR-gamma agonists suggest that they may provide a novel intervention strategy to prevent vascular and glomerular sclerosis.

Animals↗
PubMed2004

Anemia and diabetes.

World Health Organization statistics identify 150 million people with diabetes mellitus worldwide and suggest that this figure may double by 2025. In countries with a western lifestyle, the number of patients admitted for renal replacement therapy with diabetes as a co-morbid condition has increased significantly up to three to four times in a period of 10 years. Diabetes and renal failure are thus tightly linked diseases, and so is anemia. However, whether anemia may be worsened and/or directly, at least in part, caused by diabetes is not clearly elucidated yet. In this article, we review the prevalence, pathophysiology and consequences of anemia in diabetic patients.

Anemia↗
PubMed2004

[Value of N-acetylcysteine to prevent nephrotoxicity from iodinated contrast agents].

Renal toxicity of contrast agents remains an up-to-date challenge. N'Acetyl cystein is an antioxyde agent which efficacy has been proved in various models of experimental renal ischemia and therefore proposed in the prevention of renal failure due to intravenous iodine contrast media. The Author of this review reports and comments these studies in order to better define indications of N'Acetyl cystein in this clinical context.

Acetylcysteine↗
PubMed2004

Renal effects of PPARalpha-agonists.

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the large nuclear receptor superfamily. Its main role is to activate genes involved in fatty acid oxidation in the liver, heart, kidney and skeletal muscle. While they are mainly used as hypolipidemic agents, PPARalpha agonists may also be postulated to exhibit renoprotective effects. This review summarizes current knowledge regarding the effects of PPARalpha agonists on the kidney.

Humans↗
PubMed2003

Assessing residents' prescribing behavior in renal impairment.

OBJECTIVE: Although fitting orders to renal function avoids overdosage and therefore iatrogenic risk, dosage adjustment is rarely made. The objective of this study was to assess residents' prescribing behavior in renal impairment, through a standardized simulated clinical setting. METHOD: This criterion-referenced study was carried out in a French teaching hospital. The hospital had 118 residents; 71 of them were asked to complete a questionnaire including four vignettes, simulating drug prescription in four 'patients' with various degrees of renal impairment (16 orders). The patients had an order of gentamicin sulfate, diclofenac sodium, and amlodipine bensylate. For each drug, the resident could maintain the order, discontinue the order, or change the dosage. A fourth drug, enalapril maleate, was to be started, with three possible dosages and the possibility of not prescribing it. The reference chosen for assessment was the Vidal dictionary, which corresponds to the Physician's Desk Reference and is the French reference for prescription. RESULTS: All the residents approached for the survey accepted the offer to complete the questionnaire. Among the 16 simulated orders, the median number of appropriate orders per resident was nine. Considering the renal function of their patients, 62% of residents wrote an inappropriate order for gentamicin, 42% wrote an inappropriate order for didofenac, and 52% wrote an inappropriate order for enalapril. Although no adjustment to renal function was required, 28% of the residents decreased the dosage of amlodipine and ordered an underdose. CONCLUSION: Considering the iatrogenic risk related to the lack of dosage adjustment, attention should be drawn to increasing residents' awareness of dosage adjustment in renal impairment and to providing them with better information on patients' renal function.

Aged↗
PubMed2003

Medication misuse in hospitalized patients with renal impairment.

OBJECTIVES: The potential consequences of medication misuse in renal impairment have not been assessed in a population of in-patients. The purpose of this study was to determine the frequency and potential consequences of a lack of dosage adjustment in hospitalized patients with renal impairment. DESIGN: Order sheets for in-patients having a creatinine above 0.7 mg/dl were analysed. We considered the appropriateness of prescriptions for medications having potential nephrotoxicity and/or eliminated through renal excretion or metabolism (TEM medications) and having manufacturer's guidelines for dosage adjustment in renal impairment. MAIN MEASURES: On the basis of these guidelines, each line of prescription was rated as 'appropriate order', 'inappropriate dosage', or 'contra-indicated order'. Experts also rated prescriptions as potentially fatal or severe, serious, significant, or without potential for increased adverse effects. RESULTS: Two hundred and two order sheets were completed for 164 patients. They totalled 1469 lines of prescription, 85% of which were TEM medications, with guidelines for dosage adjustment for 71% of them (n = 886). Of these 886 prescriptions, 34% were inappropriate, 14% being contra-indicated and 20% with inappropriate dosage given the patient's renal function. Among the 202 order sheets, 75% included at least one inappropriate prescription. Sixty-three per cent included at least one prescription with potentially adverse consequences, 3% of these having potentially fatal or severe consequences. CONCLUSION: This study confirms that physicians do not take into account sufficiently patient renal function when prescribing. In light of these results, improving the quality of drug prescription in patients with renal impairment could be of importance for improving the quality of care.

Aged↗
PubMed2003

Antiviral drug-induced kidney and electrolytes disorders.

HIV patients are at a high risk for nephrotoxicity (HIV-induced nephrotoxicity, HIVAN). As a result, renal insufficiency, tubular dysfunction and renal-related biological disorders are frequently observed in those patients. However, in some cases those defects or anomalies in renal function may be related to antiviral therapies rather than the disease itself. This article reviews the incidence, presentation, prevention and management of antiviral drug-induced renal dysfunction.

Anti-HIV Agents↗