Dr. Manikkam Suthanthiran
Kidney transplant patients whose bodies are rejecting their new organs currently have to undergo needle biopsies to monitor their progress, but Weill Cornell Medical College researchers say they've developed a new method that's non-invasive and just as effective:
A urine test.
"This test can now allow us to avoid many of the biopsies that we need to do," said Dr. Manikkam Suthanthiran, chief of the Division of Nephrology and Hypertension at Weill Cornell and chairman of the Department of Transplantation Medicine at NewYork-Presbyterian Hospital/Weill Cornell Medical Center who led the landmark study published in the journal Transplantation. "Biopsies can be associated with bleeding and transplant failure and, sometimes, even death, and with this new test, many of the biopsies could be avoided."
All kidney transplants that ultimately fail have developed fibrosis, or scarring. A kidney biopsy, considered the gold standard test to diagnose and monitor this condition, can only catch complications once they arise and the damage is already done. Dr. Suthanthiran, also the Stanton Griffis Distinguished Professor of Medicine, professor of medicine in surgery and professor of biochemistry at Weill Cornell, sought to understand why fibrosis occurred in some patients, and if there is a better, more preemptive way of diagnosing and monitoring the process.
Certain proteins have been implicated in the fibrosis process and the mRNAs encoding these proteins were measured in urine samples using gene expression monitoring assay developed in the Suthanthiran laboratory. Dr. Suthanthiran and his colleagues measured the levels of mRNAs in urine from patients with fibrosis in their kidney grafts and from patients without fibrosis and discovered and validated a 4-gene signature accurately diagnostic of kidney graft.
"Right now, we find out about fibrosis after the fact, after much damage has been done to the kidney transplant and the diagnosis is made using the invasive biopsy procedure," Dr. Suthanthiran said. "We hope to identify fibrosis before it is fully advanced so we can not only anticipate it, but also initiate treatment at an earlier time."
It also enables doctors to personalize treatments for the individual patient based upon his or her own need, transforming the current one-size-fits-all paradigm, Dr. Suthanthiran said.