What is contrast-induced nephropathy (CIN)?

What is contrast-induced nephropathy (CIN)?

• A. A condition where there is a 25% increase in creatinine from baseline after contrast administration
• B. A decline in creatinine after contrast
• C. An allergic reaction to contrast
• D. A nonspecific kidney stone formation

Answer: (A)

Contrast-induced nephropathy is acute kidney injury that happens after iodinated contrast exposure. It is diagnosed when serum creatinine rises from baseline after the contrast, typically about a 25% increase (or an absolute rise of roughly 0.5 mg/dL) within 48–72 hours, with no other explanation. This definition is what makes the option describing a 25% creatinine increase after contrast the best answer. It isn’t a decline in creatinine, which would indicate improved function; it isn’t an allergic reaction, which involves hypersensitivity symptoms; and it isn’t related to kidney stone formation, which is a different renal process.

Contrast-induced nephropathy is acute kidney injury that happens after iodinated contrast exposure. It is diagnosed when serum creatinine rises from baseline after the contrast, typically about a 25% increase (or an absolute rise of roughly 0.5 mg/dL) within 48–72 hours, with no other explanation. This definition is what makes the option describing a 25% creatinine increase after contrast the best answer. It isn’t a decline in creatinine, which would indicate improved function; it isn’t an allergic reaction, which involves hypersensitivity symptoms; and it isn’t related to kidney stone formation, which is a different renal process.