THURSDAY, April 14 (HealthDay News) -- Kidney transplant patients whose immune systems produce antibodies that target the new organ can develop accelerated narrowing of the arteries that supply blood to the kidney, which may lead to organ rejection.

That's the finding of a study by researchers in France who examined kidney biopsies from 99 kidney transplant patients -- 40 with antibodies targeting their new kidney and 59 without the antibodies.

Significant progression of arteriosclerosis in kidney arteries during the three to 12 months after transplant occurred in the antibody-positive patients, but not in the antibody-negative patients. The rate of artery narrowing, or arteriosclerosis, in the antibody-negative patients was about one-third that seen in the antibody-positive patients.

The rate of arteriosclerosis in the antibody-positive patients was much worse than expected and translated into about 28 years of "aging" of the new kidney in the first year after transplantation, the researchers said in an American Society of Nephrology news release.

"This accelerated arteriosclerosis can now be seen to form part of the rejection process, and it will probably be found to contribute to the ultimate decline of kidney function," said study author Dr. Gary Hill, of the Georges Pompidou European Hospital in Paris.

The study appears in an upcoming issue of the Journal of the American Society of Nephrology.

The findings highlight the importance of arteriosclerosis following a kidney transplant, the researchers said.

More information

The National Kidney Foundation has more about kidney transplant.