Iodinated contrast media‐induced nephropathy: pathophysiology, clinical aspects and prevention

Abstract

Administration of iodinated contrast media (CM) for radiographic purposes is a preoccupying cause of acute renal failure. This review of the literature deals with what is known about physiopathology, clinical course, risk factors and prevention. Factors involved in the pathophysiology of CM-induced acute renal failure are vasoconstriction, direct tubular cell injury and tubular obstruction by casts. In the case of pre-existing renal hypoperfusion, CM may disturb the complex interaction between factors which modulate renal haemodynamics by increasing vasoconstrictor factors, notably endothelin peptides. The renal medulla, a zone characterized by a high metabolic activity and a low oxygen tension, may be a specific target for CM-induced effects. CM-induced nephropathy (CMN) is essentially observed in patients with one or more associated risk factors (chronic renal failure, dehydration, diabetes mellitus with impaired renal function, multiple myeloma, large CM volume, intra-arterial rather than intravenous route, etc). There is much debate as to whether newer low osmolar CM (LOCM) are better tolerated than conventional high osmolar CM (HOCM). Most of the animal studies clearly demonstrate the advantages of LOCM over HOCM. Clinical literature is far more confusing, although some recent studies and one meta-analysis demonstrate that LOCM are better tolerated in patients with impaired renal function. The low number of comparative clinical trials carried out in high risk patients, wide variability in CMN definitions, limited number of patients enrolled and inadequacy of various selected endpoints may explain difficulties experienced in demonstrating this advantage. Furthermore, while hydration is correctly maintained during clinical trials, this is not always true in clinical practice. Such a discrepancy could lead to underestimation of the potential advantage of LOCM over HOCM. Effective prevention should associate the correct hydration of patients, identification and, when possible, optimal correction of risk factors, avoidance of repeated CM injections within a short period of time and temporary disruption of treatment with other nephrotoxic drugs (non steroidal antiinflammatory drugs, aminoglycosides, etc).

The effect of radiological contrast media on renal function and inflammatory markers in people with diabetes – a clinical study and review

“…In addition, we did not collect the presence of contemporaneous infection in individual patients. It has previously been shown that the volume of CM administered is related to the risk of developing CIN, 32 however, these data were not collected. Finally, given the retrospective nature of the study, we were unable to collect all of the data and were limited to those collected in 'real life' clinical practice.…”

Proteomic Analyses of Contrast Media-Treated Mesangial Cell

“…All the radiocontrast substances cause glomeruli hemodynamic alterations such as decline in the filtration rate and an increase of medullar hypoxia. Iodine Contrast Media can be a cause of ARF in patients with diabetes, dehydration, hypertension, renal insufficiency, aged over 60, heart failure and exposure to other nephrotoxins [21,22].…”

“…In patients presenting with conditions such as diabetes, dehydration, hypertension, renal insufficiency, aged over 60 years, diabetic nephropathy, heart failure, concomitant exposure to other nephrotoxins are more susceptible to ARF caused by CtM [12,22].…”

Advances in the Understanding of the Nephrotoxicity of Radiocontrast Media

“…It is now evident that the development of such nephrotoxicity is low in people with normal renal function, but with pre-existing renal impairment the incidence may be ranging from 12 to 27% [4, 5, 6]. Pre-existing renal impairment, in particular diabetic nephropathy, and large doses of RCM are important predisposing factors, for the development of RCMN [1, 2, 3]. In addition, high-osmolar CM (HOCM) are more nephrotoxic in comparison to low-osmolar CM, particularly in patients with pre-existing renal impairment [7, 8, 9, 10].…”

“…Radiocontrast media (RCM) nephrotoxicity (RCMN) refers to a condition in which an impairment in renal function (an increase in serum creatinine by more than 25% or 44 µmol/l) occurs within 3 days following the intravascular administration of RCM in the absence of another alternative aetiology [1, 2, 3]. It is now evident that the development of such nephrotoxicity is low in people with normal renal function, but with pre-existing renal impairment the incidence may be ranging from 12 to 27% [4, 5, 6].…”