Now, urine test can diagnose as well as predict rejection of transplanted kidneys

A urine test can now determine whether a transplanted kidney recipient is in the process of rejecting the donated organ, as well as identifying who is at risk of rejection several weeks and even months before symptoms appear.

By measuring just three genetic molecules in a urine sample, the test accurately diagnoses acute rejection of kidney transplants, the most frequent and serious complication of kidney transplants, says the study's lead author, Dr. Manikkam Suthanthiran, the Stanton Griffis Distinguished Professor of Medicine at Weill Cornell Medical College and chief of transplantation medicine, nephrology and hypertension at NewYork-Presbyterian Hospital/Weill Cornell Medical Center.

"It looks to us that we can actually anticipate rejection of a kidney several weeks before rejection begins to damage the transplant," Dr. Suthanthiran says.

The test may also help physicians fine-tune the amount of powerful immunosuppressive drugs that organ transplant patients must take for the rest of their lives, Dr. Suthanthiran, whose laboratory developed what he calls the "three-gene signature" of the health of transplanted kidney organs, said.

"We have, for the first time, the opportunity to manage transplant patients in a more precise, individualized fashion. This is good news since it moves us from the current one-size-fits-all treatment model to a much more personalized plan," he says, noting that too little immunosuppression leads to organ rejection and too much can lead to infection or even cancer," the researcher said.

Such a test is sorely needed to help improve the longevity of kidney transplants and the lives of patients who receive these organs, says study co-author Dr. Darshana Dadhania, associate professor of medicine and medicine in surgery at Weill Cornell Medical College and associate attending physician at New York-Presbyterian Hospital.

The study is published in The New England Journal of Medicine (NEJM).