[Contrast-induced nephropathy. Current concepts and propositions for Italian guidelines].

Contrast-induced nephropathy is an impairment in renal function following intravascular exposure to radiographic contrast media (CM). Kidney damage may be limited to an asymptomatic increase in serum creatinine or reveal itself as acute renal failure, which can require renal replacement therapy. The aim of the present review is to describe the most recent knowledge concerning this matter. Viscosity and/or osmolality of iodinated CM might be involved in the activation of intrarenal vasoconstriction, with a subsequent decrease in glomerular filtration rate. Reduced bioavailability of physiological vasodilators, such as prostaglandins and nitric oxide, could predispose to acute renal damage. The volemic expansion and hydration of the patient, by the peri-procedural infusion of saline solutions constitutes even today the most effective prophylactic mechanism. It is probable, in fact, that in this way the dilution of CM and the inhibition of the activation of intrarenal vasoconstrictive mechanisms are obtained.