Contrast-induced nephropathy

Contrast-induced nephropathy (CIN) is a form of kidney damage in which there has been recent exposure to medical imaging contrast material without another clear cause for the acute kidney injury. CIN is associated with a significant increase in morbidity and mortality, length of hospital stay and in healthcare costs.

Definition

Contrast-induced nephropathy is traditionally defined as a serum creatinine increase of 25% or more from baseline or an absolute increase of 0.5 mg/dL within 48-72 hours of intravascular iodinated contrast material exposure, in the absence of an alternative etiology.

Epidemiology

The incidence of CIN varies widely, depending on the definition used, the population studied, and the prophylactic measures taken. In the general population, the incidence of CIN has been reported to be less than 2%. However, in patients with pre-existing renal insufficiency, diabetes mellitus, or both, the incidence of CIN can exceed 25%.

Pathophysiology

The pathophysiology of CIN is complex and not completely understood. It is believed to involve direct toxicity to renal tubular epithelial cells and renal medullary hypoxia due to alterations in renal blood flow.

Prevention and Treatment

Prevention of CIN includes identification of high-risk patients, appropriate choice and dosing of contrast material, and prophylactic hydration. Treatment of established CIN is supportive, as there is currently no specific therapy available.

See Also

• Acute kidney injury
• Renal insufficiency
• Diabetes mellitus