Renal effects of cardiac angiography with different low-osmolar contrast media

Dose individualization can minimize nephrotoxicity due to carboplatin therapy in patients with ovarian cancer

Carboplatin (Carbo-Pt), an alkylating agent cleared from the plasma through glomerular filtration, is commonly used for the treatment of ovarian cancer. When administered at high dosage or to patients with reduced renal function, Carbo-Pt may be nephrotoxic. The dose of Carbo-Pt is calculated with Calvert formula, using the value of 24-hour creatinine clearance (24h Ccr) as an estimate of glomerular filtration rate (GFR). The aim of this study was to evaluate the possibility of individualizing the dose of Carbo-Pt using an alternative method to estimate GFR, based on body composition analysis, and then to assess the nephrotoxicity of Carbo-Pt therapy individualized with this new method. First, we evaluated the agreement between GFR (renal clearance of diethylene triamine pentaacetic acid (99mTc-DTPA)), 24h Ccr, and the new estimate of GFR (BCMGFR) calculated on the basis of individual values of body cell mass (BCM) and plasma creatinine. BCMGFR gave a better estimate of GFR than 24h Ccr. Then, we evaluated the nephrotoxicity of a combination chemotherapy based on Carbo-Pt (AUC(5-6)) in 23 patients affected by ovarian cancer. The dose of Carbo-Pt was adjusted to residual renal function of patients, evaluated as BCMGFR. No case of acute renal failure was observed with this treatment regimen. Urinary excretion of proteins (albumin, beta2-microglobulin, and retinol-binding protein) and tubular enzymes, measured as markers of tubular damage, increased significantly and transiently only in the first days after chemotherapy, whereas no evidence of chronic nephrotoxic effect was documented. Dose individualization, using the value of BCMGFR, may minimize nephrotoxicity due to Carbo-Pt therapy.

Nephrotoxicity of iso-osmolar iodixanol compared with nonionic low-osmolar contrast media: meta-analysis of randomized controlled trials

PURPOSE

To compare the nephrotoxicity of iso-osmolar iodixanol with that of nonionic low-osmolar contrast media (CM) (LOCM) in randomized clinical trials.

MATERIALS AND METHODS

This meta-analysis was conducted with a systematic search of MEDLINE, EMBASE, BIOSIS, Web of Science, ISI Web of Knowledge, Current Contents Medizin, Cochrane Library (until August 2007), trial registers, conference proceedings, and reference lists to identify studies and with requests from all manufacturers of CM for unidentified studies. Randomized controlled trials assessing serum creatinine levels before and after intravascular application of iodixanol or LOCM were included. The primary outcome measures were the incidence of contrast medium-induced nephropathy (CIN) and change in serum creatinine levels.

RESULTS

Twenty-five trials were included. Iodixanol did not significantly reduce the risk of CIN (relative risk [RR], 0.80; 95% confidence interval [CI]: 0.61, 1.04; weighted mean difference in serum creatinine increase, 0.01 mg/dL [0.88 mumol/L]; 95% CI: -0.01, 0.03). There was no significant risk reduction after intravenous administration of the CM (RR, 1.08; 95% CI: 0.62, 1.89); subgroup with preexisting renal insufficiency (RR, 1.07; 95% CI: 0.56, 2.02) or after intraarterial administration (RR, 0.68; 95% CI: 0.46, 1.01); subgroup with preexisting renal insufficiency (RR, 0.59; 95% CI: 0.33, 1.07). However, in patients with intraarterial administration and renal insufficiency, the risk of CIN was greater for iohexol than for iodixanol (RR, 0.38; 95% CI: 0.21, 0.68), whereas there was no difference between iodixanol and the other (noniohexol) LOCM (RR, 0.95; 95% CI: 0.50, 1.78).

CONCLUSION

Iodixanol is not associated with a significantly reduced risk of CIN compared with the LOCM pooled together. However, in patients with intraarterial administration and renal insufficiency, iodixanol is associated with a reduced risk of CIN compared with iohexol, whereas no significant difference between iodixanol and other LOCM could be found.

Contrast medium use

Various properties of iodinated contrast media (osmolality, ionic versus nonionic, and viscosity) may contribute to contrast-induced nephropathy (CIN). Therefore, the choice of contrast medium affects the risk for CIN. There is good evidence that low-osmolar contrast media are less nephrotoxic than high-osmolar contrast media in patients at increased risk for CIN who receive intra-arterial iodinated contrast. Current evidence suggests that nonionic isosmolar contrast presents the lowest risk for CIN in patients with chronic kidney disease (CKD), particularly in those patients with diabetes mellitus. Intra-arterial administration of contrast media may be associated with a greater risk for CIN above that observed with intravenous administration. The use of gadolinium or CO(2) as alternative contrast media to avoid the risk of nephrotoxicity cannot be substantiated by clinical trials and therefore cannot be recommended. Most studies show that, within a class, higher volumes (>100 mL) of iodinated contrast medium are associated with a higher risk for CIN. However, in patients at high risk, such as those with CKD and diabetes, even small volumes of contrast medium can have adverse effects on renal function.

Nephrotoxicity due to Combination Antibiotic Therapy with Vancomycin and Aminoglycosides in Septic Critically Ill Patients

The aim of this prospective observational study was to evaluate the incidence of nephrotoxicity due to combination therapy with vancomycin and aminoglycosides in septic critically ill patients admitted to the intensive care unit.

METHODS

Thirty consecutive critically ill patients were treated with vancomycin concurrent with aminoglycosides for sepsis. Inclusion criteria were: the need for mechanical ventilation and the presence of severe infection due to bacteria susceptible to vancomycin and aminoglycosides. Exclusion criteria were: age <18 years, impaired renal function (24-hour creatinine clearance <90 ml/min) or previous adverse reaction to either drug. Serum creatinine and urea concentrations, creatinine clearance, 24-hour urinary excretion of proteins, beta2-microglobulin and enzymes were measured immediately before starting therapy and at different times thereafter.

RESULTS

Eleven of the 30 patients had a transient and modest increase in serum urea, 15 patients presented with urinary excretion of beta2-microglobulin and tubular enzymes, and 14 patients had urinary proteins. In the only patient with severe acute renal failure (serum creatinine 8.2 mg/dl), the clinical course was complicated by prolonged hypotension.

CONCLUSION

Concurrent administration of vancomycin and aminoglycosides to critically ill septic patients with normal renal function at baseline induced mainly slight and transient toxic tubular effects. The only clinically significant nephrotoxic event occurred in a patient with septic shock.

Contrast nephropathy after coronary angiography

Contrast nephropathy after coronary angiography is associated with considerable morbidity and mortality. We discuss the incidence, definition, and pathologic mechanisms of contrast nephropathy; provide an overview of risk factors; highlight proven preventive interventions; clarify which interventions have shown no benefit; and discuss future possibilities. The prevention of contrast nephropathy is crucial for the care of patients undergoing coronary angiography and should be possible with an understanding of risk factors and proven management strategies.

Contrast media augmented apoptosis of cultured renal mesangial, tubular, epithelial, endothelial, and hepatic cells

RATIONALE AND OBJECTIVE

Nephrotoxicity of contrast media, resulting in apoptosis and acute necrosis of tubular cells, is well documented. No studies concerning mesangial cells apoptosis have been published yet.

AIM

Apoptosis of cultured mesangial, tubular, and hepatic cell lines was investigated following exposure to different contrast media.

METHODS

Apoptosis was assessed by TUNEL assay and verified by Mayer Hematoxylin staining.

RESULTS

Iopromide, Ioxaglate, and Ioxatalamate induced apoptosis in all cell cultures at final concentrations ranged from 0.1% to 10.0%. However, only 1% to 10% Iomeprol elicited a significant apoptosis. Moreover, at 10% concentration, Iomeprol induced significantly less apoptosis than Iopromide, Ioxaglate, or Ioxatalamate.

CONCLUSIONS

First, Iomeprol, which has a different physico-chemical properties, proved to be less proapoptotic compared with other contrast compounds. Second, all types of cells similarly respond by apoptosis to contrast media induced injury. However, apoptosis of mesangial cells might generate additional deleterious effects in vivo.