[Contrast nephropathy and its prevention]

Contrast-induced nephropathy is one of the adverse events of diagnostic and therapeutic intravascular application of contrast agent. In general, the condition was defined as an increase in the serum creatinine concentration of more than 44 mmol/l or of more than 25% within 48 hours after the contrast agent administration. Other cause of creatinine increase should be excluded. Contrast-induced nephropathy has been reported to be the third leading cause of acute nephropathy in hospitalized patients, occurring at a rate of 1-6% in unselected population and of 30-50% in high-risk patients. One year mortality can be as high as 45% in high-risk patient population. The most important risk factors are chronic renal insufficiency, diabetes mellitus and high volume of contrast agent. Clinical presentation is mostly asymptomatic, but in some patients acute renal failure with necessity of hemodialysis can occur. Prevention is underlying tool in reducing of contrast-induced nephropathy incidence. It is based on the identification of risk patients, stop of medication which can increase risk of contrast-induced nephropathy and proper hydratation of patients before, during and after the contrast agent administration. In high-risk patients, non-ionic and low-osmolarity contrast agent should be used. Several clinical studies testing different drugs to prevent contrast-induced nephropathy were performed, but no convincing result has been found. Promising substancies are N-acetylcysteine and fenoldopam.