Scientists make progress on test for bladder ailment
Dr. Vicki Ratner tried everything: She had surgery to stretch her bladder. She took a pill designed to coat the organ’s inner wall. She began an “elimination” diet that started with eating nothing but rice.
She even had a Los Angeles jeweler fashion a mold for a urethral suppository containing cortisone and antibiotics.
But only a low-dose pain medication has given the 53-year-old orthopedic surgeon relief from her interstitial cystitis, a chronic and often-debilitating bladder disorder that affects about a million people -- mostly women.
Researchers have been trying for decades to better understand the painful and difficult-to-diagnose problem, which has no cure.
And, although they still haven’t unlocked the mystery, scientists at the University of Maryland School of Medicine and the National Cancer Institute have come one step closer to developing a diagnostic test and, potentially, more effective treatments.
Reporting recently in the online Proceedings of the National Academy of Sciences, the team described for the first time the structure of a toxin found in the urine of most interstitial cystitis, or IC, patients.
The toxin, known as antiproliferative factor, inhibits the growth of epithelial cells in the bladder, which line and protect the organ’s inner wall.
“Now that we know the structure, and we can make it synthetically, we can make it in large enough quantities to be able to develop antibodies or other reagents for a diagnostic test,” said Dr. Susan Keay, professor of medicine at the University of Maryland and the study’s lead investigator.
What’s more, she said, knowing the toxin’s makeup should help researchers understand how it works inside the bladder -- which could yield better treatments.
Symptoms of the disorder -- which include urinary urgency and frequency as well as pelvic pain -- can be so severe that only about half the patients who have it can work full-time.
Over the years, researchers have tested various hypotheses about the origins of the disorder.
Keay and her colleagues said the antiproliferative factor they have described -- which keeps the protective cells that line the bladder from growing -- might be the root of the problem.
The encouraging news is that, once the toxin is removed, the epithelial cells start growing again after a week or 10 days.
“I think this will give patients a lot of hope,” said Ratner of San Jose, who founded the Interstitial Cystitis Assn. in 1984 and has lobbied for more federal research funding.
