X-ray dyes may harm kidneys

By HSC Staff Writer • Published: December 14th, 2006
Category: Health in a Heartbeat

They say one picture is worth a thousand words.

And if you’re a cardiac patient, images showing your heart at work can be worth much more.

Doctors can assess cardiac function using X-rays enhanced with opaque dyes.

For most patients, this procedure is safe. But for people with chronic kidney disease, the dyes sometimes impair kidney function.

This phenomenon is called radiocontrast nephropathy [RAY-dee-oh-CONN-trasst neff-RAW-puh-thee], or R-C-N. It can lead to increased risk of death.

But doctors disagree about how to define it.

The main warning sign of R-C-N is a buildup of the chemical creatinine [kree-ATT-uh-NEEN] in the bloodstream.

Some doctors believe the best indicator of R-C-N is the amount of creatinine in the blood. Others say it’s the percentage of the increase that matters.

Researchers tried to resolve this controversy in a study published recently in the Journal of the American Society of Nephrology.

They reviewed data from more than ten-thousand patients who received a cardiac X-ray procedure.

The scientists developed a detailed breakdown showing the risk associated with various creatinine measurements.

For example, when creatinine levels rose by five milligrams per liter of blood, there was about six percent greater risk of death.

Similarly, when creatinine levels rose by fifty percent, patients were about eight percent more likely to die.

Less than ten percent of the patients had elevated creatinine levels. But this study will help doctors pinpoint those who need close observation.

So these findings shouldn’t discourage anyone from getting potentially life-saving cardiac X-ray procedures… get the picture?