As a kid, Briget Shields suffered from terrible leg cramps. "Growing pains," her doctor said.

But what about her skinny legs, the fragile ankles she would sprain or break if she tried to engage in sports? No one really thought too much about them. Not everyone has big, muscular legs, and kids do get hurt, you know.

About three years ago, though, more things began to go wrong for the wife of city council President Doug Shields, who is also a trained fashion illustrator, jewelry maker and art handler for the Frick Fine Arts Museum.

"I had leg cramps, twitches, burning and weakness in my lower legs. I started losing my balance," said Ms. Shields, 55, of Squirrel Hill. There was a "strange fatigue," and, after sitting several hours, her legs would go numb.

"That's where it started," she said. "I was convinced I had Lyme disease because I'm a fly fisherman."

She was wrong.

Well, then maybe, she thought, it was multiple sclerosis, "but that was ruled out by an MRI. Then the doctors eliminated Lou Gehrig's disease and lupus."

Ms. Shields started to worry that she was nothing more than a hypochondriac.

Finally, one day when she was undergoing an electromyogram, the technician looked at her reaction to electroshock and exclaimed, "I think she has CMT."

And so, about a year after she started looking for the cause of her problems, it was confirmed by a new series of tests: Ms. Shields has Charcot-Marie-Tooth, or CMT, the most commonly inherited peripheral neuropathy, or disease of the nerves. It affects an estimated 150,000 Americans and more than 2.5 million people worldwide. There are treatments for the disorder, which as it progresses causes patients to lose normal use of their feet/legs and hands/arms, but there is no cure. It generally is not fatal.

"Once you're diagnosed, there are things you can do, and it makes you feel you're not a hypochondriac," Ms. Shields said. "I was actually grateful when I was diagnosed with CMT."

One of the things she did was learn everything she could about the disorder, which was discovered in 1886 by three physicians, Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth. That research led her to the Chester, Pa.-based Charcot-Marie-Tooth Association, a nonprofit organization whose goals are patient support, public education, promotion and funding of research and the treatment and cure of CMT.

Ms Shields has recently signed on to act as a fund-raiser and advocate as the CMTA conducts two major initiatives.

One is called the Accelerated Research Collaboration; the other is the CMT Prevalence Study.

In the former, a small group of scientists spread out across the nation has been guaranteed funding through a $350,000 challenge grant to find a cure for the three most common forms of CMT within the next three to five years. They will be looking for it -- or them -- among a list of 100,000 over-the-counter remedies already approved by the Food and Drug Administration.

In the latter, which is funded by the Pennsylvania Department of Health, the CMTA is seeking to determine exactly how many people have the neuropathy by surveying the population of eight Western Pennsylvania counties, including Allegheny and Westmoreland, plus Bedford, Blair, Cambria, Clearfield, Indiana and Somerset.

"It's the first prevalence study on CMT in the United States," said CMTA executive director Charles F. Hagins. "We were planning on doing all of Pennsylvania, but we may only have to thoroughly do eight counties to extrapolate back. We sat down with the Conemaugh Health Systems [John P. Murtha Neuroscience Center and Pain Institute, which has a CMT clinic], and the people who do studies say it is more important to get a good count than to spread it out further."

To that end, the CMTA has been running public service ads on television featuring Penn State football coach Joe Paterno, who speaks about some of the symptoms of CMT and asks people who know or fear they have it to take part in the survey. That is accomplished by filling out and sending in a brochure available in many neurologists' offices, linking to the CMTA Web site at www.charcot-marie-tooth.org or by calling the Murtha Institute toll-free at 1-888-405-0139.

Meanwhile, Ms. Shields has met with Mr. Hagins and volunteered to take on two projects: organizing a support group and a fund raiser. Her doctor and her husband also are involved. Dr. Chitharanjam V. Rao, a UPMC neurologist, was the lead speaker at a patient-family conference in Monroeville in June; Mr. Shields got city council to issue a proclamation establishing a CMT awareness week this past summer.

"Briget, since she's been made aware of us, has been a great advocate with Doug," Mr. Hagins said.

"You've got to give a person like Briget a lot of credit," he added. "She took charge of her disorder. A lot of people just sit back and complain. She said, 'I'm not going to do this. I'm going to do something [positive]. She's found there's light at the end of the tunnel."

One of the first things Ms. Shields did after her own diagnosis and research was to get her father diagnosed with CMT after years of misdiagnoses and suffering.

CMT is passed on from parent to child in an autosomal dominant pattern. That means that if one parent has CMT, each child has a 50-50 chance of inheriting the gene and the disease. So far Ms. Shields is the only one of four siblings to be diagnosed with CMT, but the other three aren't necessarily in the clear. Ms. Shields and her father suffer from one of the rare forms of CMT, one in which the symptoms usually show up later in life.

Ms. Shields' 22-year-old daughter Liza, a fashion designer in New York, has tested negative for CMT. Her son, Elliot, 24, and an art school student in San Francisco, has not yet been tested.

Over the three years since her diagnosis, Ms. Shields' symptoms have worsened. She has hammer toes, a frequent symptom, and chronic pain. She wears orthotics for raised arches, another classic symptom.

"I don't want it to sound like I'm a big complainer," she said. "It's not fatal -- that's a big plus. It doesn't affect organs like MS does. ... I feel very fortunate that I'm not in leg braces. I'm still walking. But I attribute that to my staying active and doing exercises."

She begins each day with a yoga stretch. She takes lots of hot baths and does low-resistance exercise like walking and swimming.

"I don't use traditional medicine," Ms. Shields said. "I do a lot of supplements, herbal remedies."

She does take ibuprofen and, when absolutely necessary, takes stronger painkillers prescribed by a team of doctors she praises at every opportunity.

Though physical therapy is beneficial, she doesn't use conventional p.t. because the first therapist she went to didn't know what CMT was.

"One of my goals is to help raise the awareness of doctors, physical therapists and especially pediatric neurologists," Ms. Shields said. "The awareness of CMT is so foreign in medicine."