(CBS News) Sally Massagee looked like a bodybuilder, but she wasn't. Rather, a mysterious affliction was causing Sally's muscles to grow out of control, and it threatened to affect her heart. After stumping all the experts, Sally finally ended up in the care of Dr. William Gahl at the NIH's Undiagnosed Disease Program -- the last, best hope for people like Sally with rare, debilitating, and mysterious ailments. Lara Logan reports on doctors and patients facing off against unknown illnesses.
The following script is from "Hard Cases" which originally aired on May 20, 2012. Lara Logan is the correspondent. Howard Rosenberg, producer.
Every day across America, people wake up suffering from symptoms of diseases that have never been identified. There are thousands of illnesses passed from generation to generation -- genetic diseases -- about which doctors know next to nothing.
But inside the National Institutes of Health -- the government's premier medical research facility in Bethesda, Maryland -- there's a small group of scientists devoted to unraveling the mysteries of the human body and finding cures.
The doctor in charge, William Gahl, takes on only the hardest of the hard cases.
William Gahl: There's -- a really significant percentage of the American population that has a rare disease.
Lara Logan: Millions of Americans.
William Gahl: We are talking about millions of me-- Americans. There's no question about that.
Dr. William Gahl is the tireless force behind the Undiagnosed Diseases Program, investigating illnesses so rare they don't appear in any medical book.
Lara Logan: What defines a rare disease?
William Gahl: A rare disease in the United States is one that affects fewer than 200,000 individuals out of the 350 million citizens in the United States. That would be rare by legal definition.
Lara Logan: By your definition. 'Cause you have a different definition?
William Gahl: Something that affects 200,000 people isn't all that rare to us. I mean, when we're talking about rare diseases, the disorders were affecting between one and 50 people in the world.
[Christine Davidson: Uh, I'm so tired.]
45-year-old Christine Davidson is one of those people.
She's been struggling with an undiagnosed condition for more than half her life.
Christine Davidson: I kinda feel like my muscles are just torturing me. Yeah, my spasm in my hip squeezes so hard it just pops my bones.
Lara Logan: They are torturing you.
Christine Davidson: Yeah.
Whatever is wrong with Christine has left her unable to walk and gradually taken over her body.
Christine Davidson: I have, like, frozen shoulder syn-- like, I can't really lift my arm. And I have restrictive lung disease where the muscles are tightening so much I only breathe, like, 50 percent of what a normal person would breathe.
After years shuttling from one specialist to another, she traveled across the country from her home near Seattle to see Dr. Gahl.
Christine Davidson: I'm just getting to the point where I'm really at my last leg. So this chance to come here to be evaluated was really a big deal for me.
Four years ago, when Dr. Gahl created this program to help people like Christine, there was nothing of its kind in the U.S. Here in his lab, scientists search for links between rare, unknown diseases and genetics. As with most of his patients, he suspects Christine Davidson's own genetic makeup may be at the root of her illness.
William Gahl: Do you have a brother, sister?
Christine Davidson: Yeah, I have two brothers that are totally healthy and two sisters that do have health problems.
William Gahl: Yeah. But not this?
Christine Davidson: (Shakes her head no.)
William Gahl: So you have four siblings and your dad, and they are all available for us to get blood from them if we need it?
Christine Davidson: Yes.
As part of her evaluation, Christine must undergo a week of intense testing here at the Clinical Center of the National Institutes of Health. Dr. Gahl has a small staff and a small budget -- three and a half million dollars out of the billions the government spends on medical research here.
Lara Logan: So what's unique about what you do here?
William Gahl: We think there are a couple of things. For one, we don't take insurance. And that allows us to see patients for a week at a time as in-patients. And get done within one week what will often take a year or two on the outside. But the second thing is, we're able to gather together a bunch of experts within a single room or within a single admission in a way that often can't be done in other places.
Lara Logan: So who pays if a patient comes to you and you accept them, who's paying the bill?
William Gahl: Actually you are. I often tell the patients its taxpayers money at work. But what price would you put on making a diagnosis for a family or a patient that has desperately sought one for years?
Lara Logan: Sometimes 20 years, 30 years.
William Gahl: Yes, sometimes even decades. And what price would you put on the new discovery that one makes for a disease that now has applicability to other patients unknown, untold, not seen yet? And the possibility of allowing that diagnosis to be part of our medical armamentarium.
At the clinical center we met another one of Dr. Gahl's patient: 19-year-old Matthew Parker. He was just beginning his week of testing.
William Gahl: When was the last time you played tennis?
Matthew Parker: Probably since I was 15 I haven't played.
Matthew was once a promising tennis player. Today, he can barely move, crippled by joint pain so severe it hurts to chew his food.
[William Gahl: Anytime that we find a base-- a region like that, that's deleted...]
Dr. Gahl thinks missing genes in Matthew's DNA may be the cause.
[William Gahl: Really, what you have has all the earmarks of that.]
He does his best to explain a very complicated subject.
William Gahl: A single nucleatide polymorphism and if it's a million snip array, those snips are how far apart? This is a test.
That gentle touch of humor is part of his bedside manner. He's also careful to lower expectations, warning that even here they've only been able to give a complete diagnosis to 45 out of 450 patients.
William Gahl: And our chance for that, it's still only in the range of 10, 20 percent.
That may not sound like much, but Gahl and his team have solved cases that eluded elite institutions across the U.S. and they've discovered two new genetic diseases. A dozen more are under scientific review.
Dr. Gahl's desk is stacked high with medical records and referral letters for thousands of patients applying to the program, which can only take 150 to 170 cases a year. He personally reviews every single case. And he's the one who has to make the tough choices about who gets in and who is rejected.
William Gahl: That's part of the triage process, which is very heartbreaking and difficult to do.
Lara Logan: 'Cause you know how devastating it is for someone to be turned down.
William Gahl: We do. And we see that repeatedly when the patients come back to us saying, "You know, you are our last hope."
Lara Logan: It's a painful part of the process for you.
William Gahl: It's very difficult. It's-- I would say it's the most difficult thing that I've done in my life.
Because genetic diseases often appear early in life, 40 percent of the cases he accepts are children.
[William Gahl: There's Bryce.]
Bryce Bennett is four years old. He suffers from seizures that began soon after he was born. His parents, Jerry and Tara, have been on a frustrating medical journey his whole life trying to find the cause...
[William Gahl: And when was it first recognized that there was a neurological component to Bryce?
Tara: It was February 16 of '08-- is actually when it was.
William Gahl: Oh you remember it exactly.
Tara: Yeah. I remember.
William Gahl: And why is that that you remember?
Tara: 'Cause that was the first, like, time we took him to our local hospital 'cause I knew that it was definitely a seizure then.]
While Dr. Gahl and his team work on finding a diagnosis, Bryce and all the patients get help with new medicines, treatments and therapies. After 30 years at the National Institutes of Health, Dr. Gahl can call on a network of specialists who volunteer to help solve these cases -- a process that could take two years or longer.
When Sally Massagee met Dr. Gahl, she didn't have that much time.
Lara Logan: What can you tell me about her case?
William Gahl: Well, Sally's referral letter is sort of interesting. It came from an endocrinologist at Duke, who said, "In my 38 years of practice, I'd never seen a case like this," and so that got my attention and then the pictures caught my attention too.
Lara Logan: What did it look like, to the doctors who were treating you in those days?
Sally Massagee: One doctor said to me, "You look like you're on steroids." And, I think that probably all of 'em thought that I was. And, that I was just lyin' to 'em.
Sally Massagee was a healthy woman in her forties when her muscles began to grow out of control. She looked like a body builder. Her leg muscles became so large, she could barely walk. Her symptoms stumped more than a dozen specialists for years before she finally got a call from Dr. Gahl's office.
Lara Logan: What was that like when you got that phone call?
Sally Massagee: Oh, I was so excited. I was so excited, it was like. It was having the possibility of life where I had not had one. You know.
Lara Logan: Was it your last hope, at that point?
Sally Massagee: Oh, it certainly was. I didn't have any hopes, yes. All of them had been gone. I was out of things to try. There was nothing.
Whatever was afflicting her was spreading from one muscle system to the next.
William Gahl: This was now invading her heart muscle as well, once it gets as far as the ventricles its...
Lara Logan: It would kill her.
William Gahl: It would set to be fatal, right.
As the unknown disease advanced, Dr. Gahl's team made a dramatic discovery: she had a rare form of cancer, affecting the plasma cells of her bone marrow.
Sally Massagee: And so, I was thrilled and excited.
Lara Logan: You're probably the first person in history to be thrilled and excited to have that disease.
Sally Massagee: Probably, probably.
Lara Logan: And you finally knew what it was.
Sally Massagee: Right! Right, right. They weren't gonna figure it out at the autopsy.
Her diagnosis and a stem-cell bone marrow transplant saved Sally Massagee's life. That was almost three years ago.
Lara Logan: So what did that feel like for you to be able to solve that case?
William Gahl: Well, it was spectacular to make the diagnosis, but it was even more spectacular to have her get through the transplant.
Christine Davidson's case is more typical. She's still waiting, still hoping, but in the six months we have been following her case, the results have not been encouraging.
Lara Logan: How long will you continue to search for an answer with Christine? I mean, at which point do you say, you know, "We're never going to have anything for you?"
William Gahl: Well, in a case like Christine's, we probably will continue for years because, as I say, another case might come along to inform this case. But uh, we don't have any great clues right now to pursue.
At the moment, there are also no great clues for Bryce Bennett, but for Matthew Parker, there are some answers. Dr. Gahl and his team confirmed he has a rare inflammatory disorder that they're trying to treat, but they may never find a cure.
William Gahl: It's an incredible window into the human spirit to see people at this juncture. In other words, with a desperate disease. Again, I liken it to war. There are certain epic things in life when you see another person die or another person give up a life for someone else. And we see that in the way that people conduct themselves under these very difficult circumstances.
Lara Logan: What's that like for you as a doctor and a as human being?
William Gahl: Well, it's inspirational to me, I mean, it's what keeps us going. And it- frankly, it makes me feel more human.
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