A mom's quest: Saving her twin daughters' lives

As they grew, Addi and Cassi were delightful, playful, and normal. But shortly after their second birthday, a mysterious illness grabbed a hold of them.  It started, simply enough, with a virus: Mononucleosis. Nine months passed, and they couldn’t shake it. Plus, things had gotten worse: now some of their organs were enlarged and doctors were baffled.

Chris Hempel, mother: We did all these tests and the virus was just spinning out of control in their systems, which was unusual, so it kinda threw the doctors off.

Caroline Hastings, an oncologist and hematologist at Children's Hospital in Oakland joined the team of doctors trying to solve the riddle.

Caroline Hastings, oncologist: When I first met the girls I knew they were coming to see me for enlarged spleens and many of the common reasons for enlarged spleens had [already] been ruled out. 

Chris: They were just really sick and I don't know, I just—in my gut, I just felt something is really wrong.

Meanwhile, subtle changes were taking place: a stumble here... A tumble there…both girls were losing their balance an awful lot. And even more strange, both Addi and Cassi, who loved to sing and chatter, started slurring their words. After a grueling 18 months of questions, a shocking answer for Chris and Hugh: their twins had an incurable genetic disorder called "Niemann-Pick type C."

Hastings:  We don't really have a registry to know how many people are affected in the United States, but likely between 250 and 500 people.

The rare disease prevents Addi and Cassi's cells from processing and eliminating cholesterol. So it builds up, overloading their organs and attacking their brains.

Hastings: They just can't take care of themselves, can't move, they don't eat normally so they're very susceptible to early death.

It was unfathomable to the Hempels. They were told their beautiful little girls were quickly going to become like elderly patients with Alzheimer's or Parkinson's—mentally and physically ravaged.

Chris: You find out your kids have this devastating fatal disease and it just rings in your head again and again and again. You just can't believe it.

Hugh: Both of us were very, you know, emotional. Still are. It's not something you can prepare for.

Chris realized there was no time for self-pity.

Chris: You pick yourself up off the floor and you know I just was—I already was in action mode. I already knew who the doctor was the expert on it, what medication, experimental medication there was for it. I mean everything, all that research had been done.

But just trying to understand the jargon in the science journals became a full-time job.

Chris: It's so complicated and with no medical background, you know, you find yourself reading it ten different times and ten different ways to try to figure out what exactly are they talking about here?

Hastings: It's actually very rare that a parent comes to you and says I've been doing research. She made a point to learn about the biochemistry of this disease, about the genetics of this disease, and really try to understand it and even learn the medical terminology.

Chris's research first led her to change the girls' diet. All meat and high-cholesterol products were eliminated. Then she learned about dozens of drugs and natural supplements to treat Addi and Cassi's various symptoms.

Chris: It's a multi-system type of problem that we're trying to attack so when you have a disease like this, it's gonna take a combination of drugs and different kinds of therapies kinda similar to what they do for HIV/AIDS patients, where it's multiple types of—drugs or supplements.

Despite the hard work, Addi and Cassi were deteriorating in front of their parents' eyes. While they used to amble around and play, now they struggled to keep upright. And while Addi and Cassi used to sing, now they could hardly form a word. 

Chris knew her daughters needed a breakthrough—and fast. 

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