Transcript for 11-Year-Old Girl 'Allergic' to Sunlight
What happens when even walking outside causes extreme pain? Well, for the operative girl you're about to meet, simple pleasures like splashing in a pool or running in a playground led to a baffling set of symptoms. Until one doctor discovered the unlikely source of her suffering. Here's ABC's Abbie Boudreau. It burns! Reporter: It's every parent's worst nightmare. A happy child normally looks like this. Reduced to this. It burns, mommy! Some days she would cry for hours and hours on end. And it just felt like lava was being poured on me. Like it burned from the inside out. Reporter: A medical mystery. Hopeless. There's nothing you can do. Reporter: Savannah falkerson was 4 years old living in California when her mom noticed something strange. We'd be outside and she'd start screaming. We'd be at the pool and she's skrem she's burning, she wants to go in. I'd be like, we just got here, what is the problem? I hurt, I burn, I burn, I want to go in, I can't take it! I would really itch a lot. And it would turn my hands and feet really red. Like if I scratched too much, it would like blister kind of. Then scar. Reporter: Andrea would put Savannah's hands in bags of ice, or a Cuttino Mobley bathtub. Nothing would help. I've taken her to the doctor when she's been crying, what's wrong with her? They just tell me she as eczema. I'm going, you crew like that from eczema. Reporter: For five years they had no answers. Until they met Dr. Mineli Lu at children's hospital, los Angeles. In Savannah's case we can see that she has developed red welts on her hand as well as her fingers. Reporter: And this, along with her young age, made Dr. Lu suspect Savannah had arythropoietic porphyria. It was featured on "House." Look at her arm. Reporter: But could this be what was affecting Savannah? The challenge is body how rare the condition is, as well as the subtlety sometimes. There may be some red patches, maybe areas that look sunburned, that can lead to a long lag in diagnosis. Reporter: After years of no answers, a simple blood test finally gave them one. What did the doctors finally tell you? That she had -- say it. Erythropoirtic porypheria. Reporter: It would mean a life sentence, confined to a world of shadows. How do you explain this to your friends? That I'm allergic to the sun, I can't be out, I can never be at the beach, can never go to a sunlit pool. Literally I have to be in the dark. Dark's my home. Reporter: Savannah, now 11 years old, has to wait until evening to swim in her pool. A friend's definition of a Normal day and my definition of a Normal day are way different. Hers is bright, sunny, and beautiful. Mine's dark, cloudy, and rainy. Reporter: When she does venture out into daylight it's an effort putting on this uv protective clothing. People have made fun of you because of this? Yeah, because of my scarred hands. They called me old lady hands. Or umbrella head. Because of my big hat that goals around. So I don't get burned. They don't understand? They don't. Reporter: Savannah doesn't let that get her down. Look, you have such a good attitude about it. How is that possible? I just try to think positive. Because I know kids somewhere else have way worse than me. Reporter: The family has made adjustments for the little girl with boundless energy. You have a trampoline in your living room. Who has that? Not many people. Not many people. Reporter: Savannah's not the only kid living life in the shade. When the sun goes down, a fun summer day is just beginning for these one of a kind campers in New York City. Night baseball is fantastic, we're enjoying this, having fun, that's what counts. Reporter: These kids suffer from another rare genetic skin disorder, xp. Any exposure to sun line can cause third-degree burns and lead to cancer. I don't feel left out when I'm in camp. When I'm outside of camp, I feel left out. Reporter: When their daughter Katie was diagnosed with xp, Dan and Karen founded camp sundown in upstate New York where day is night and night is day. We do Normal kid stuff. We turn the night around and do it a different time of day. Reporter: These rare medical conditions aren't new. Some scientific historians speculate vlad of Tran ssylvania had Epp. He's believed to be the historic basis of dracula, giving rise to legends that continue this day in popular TV shows like "Vampire diaries." Run, run! Reporter: Just today, new hope for Savannah and others like her. A study about a drug treatment published in "The new England journal of medicine." With this drug you're going to increase the melanin in your skin, you're going to tan in a couple of days. The tan and melanin will act as a safety filter for the harmful rays of the sun. Reporter: Although the study's findings are promising, the drug is only available in Europe. Awaiting fda approval here in the states. At the moment, this is the only drug that's really effective as shown by the clinical studies. What is your big hope? That there's a cure out there. And like kids don't have to live with this. Reporter: Experts say less severe forms of Epp can occur. Some symptoms are redness over areas exposed to the sun, such as the nose, the cheeks, or hands. There are of course many skin conditions that can present with exactly the same findings. That's where seeking attention with either a dermatologist who specializes in children or a pore fear yeah specialist is very, very important. I wish I didn't have it. I wish no one had it. Reporter: But for Savannah and her family, the hope that maybe one day she'll be able to feel the sun on her skin without pain is enough to keep her smiling. It doesn't define me. Like, when I get older, like, it's not going to change what I want to do. Like, I'm still going to want to have like everything that I possibly can as like a Normal life. What would that Normal life look like to you? A house on the beach. On the beach? A sunny beach? Yeah. Really? Yeah. It's not going to tear me down. It's going to just build me up. Reporter: For "Nightline," I'm Abbie Boudreau in Santa Clarita, California.
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