PHOENIX (3TV/CBS 5) -- For the most common disability among children, there are three pediatric rheumatologists in the State of Arizona and some states have none.
It's a disease most people associate with aging and the elderly; stiff joints, and aches and pains from arthritis. But arthritis affects children as well, and families are traveling from neighboring states, with their little ones, to get help from Phoenix Children's Hospital.
"It's an aching, always there pain," Gwen Aron, 12, tells us. "Sometimes it's gone, but then when you go into activity it worsens."
Gwen and her brother Cooper were both diagnosed with juvenile rheumatoid arthritis, an auto-immune disease that causes pain, inflammation and stiff joints. Relief comes from an arsenal of daily medication and weekly injections made for adults.
"It's scary as heck to think about what [the meds are] doing to their system in the long-term," Kevin Aron, Gwen and Cooper's dad, explains.
And while this brother and sister try to stay active in sports, on some days a wheelchair is their reality. "You feel so alone," Lauren Aron, Gwen and Cooper's mother, says. "Even though there are so many kids, it's the number one childhood disease, we had never met anybody who had this."
According to The Arthritis Foundation, thousands of children in Arizona are living with these auto-immune diseases. In fact, the organization tells us, more children have juvenile arthritis than juvenile diabetes, muscular dystrophy, cystic fibrosis and cerebral palsy combined.
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A pediatrician first spotted the condition in Gwen when she was seven.
"She said, 'Well, she's got fluid on her knee, I'm fairly sure that this is arthritis,'" explains Lauren.
"And we were fairly certain that she was crazy," Kevin adds with a laugh.
"Yeah, kids don't get arthritis," Lauren states in agreement.
At 10-years-old, Cooper began complaining of symptoms. And it was all too familiar for the Arons.
"At times, we do see it physically," Kevin tells us. "There have been times where an arm or a knee has shown it, but more often than not, the pain is completely invisible."
But the kids try to remain optimistic, even when their bodies are hurting.
"When I try to be positive, I just look on the bright side, I say, 'Hey, I don't have to write my own homework today,' I can have my mom write it for me," Cooper tells us through his giggles.
It's the funny moments that help the Aron family smile through the pain. But they're not alone.
Some 300,000 children in the U.S. and 6,000 in Arizona are diagnosed with rheumatologic illnesses, according to the Foundation.
"Some parents will say that their child is walking like an old man or an old lady, that's the first clue for us," says Dr. Elisa Wershba, a Valley pediatric rheumatologist.
We caught up with Dr. Wershba at the Arthritis Foundation in Phoenix, who says the need for pediatric specialists in this field is growing.
"We are seeing a lot of autoimmune conditions, and more need for these doctors," Dr. Wershba says.
Dr. Wershba tells us that she's seen families seeking pediatric specialists drive in from Texas, and New Mexico, a state with just one pediatric rheumatologist. Other states lack pediatric rheumatologists altogether.
"I would call it a nationwide shortage for sure," Dr. Wershba says. In Arizona, all three pediatric rheumatologists are located at Phoenix Children's Hospital. Dr. Wershba is one of them.
"We're fortunate to be in a state that has a few, but you think about 6,000 plus kids and three doctors, it's pretty easy to see the math doesn't add up," explains Kevin.
"If we're finding there is a longer wait then we do triage, and we see the most serious patients soonest," Dr. Wershba says.
She also explains that pediatricians and rheumatologists who specialize in adults provide medical care for children with juvenile rheumatoid arthritis, which helps with the case load, but points out differences in care.
"Some people think that kids are little adults, but we in pediatrics do not think that way. Children are children," she states. "One of the biggest differences is the dose of medications we use.
"We actually see children who are treated by [rheumatologists who specialize in adults] try to put them on a lower dose of medication, for safety purposes obviously, but we actually dose medication just as aggressively. But, we use weight-based dosing."
On this day, Dr. Wershba and volunteers loaded up medicine for young patients to participate in summer arthritis camp, called Camp Cruz, which is offered by the Arthritis Foundation.
"When parents have the support of other parents, and see other children, that's the most helpful thing," says Dr. Wershba.
"When you're at camp, everybody there understands, and everybody's going through the same thing," explains Lauren. "Even most of the counselors have arthritis or an autoimmune condition, so the Arthritis Foundation has been life-changing for us and for our children."
Right now, the Arthritis Foundation is offering a fellowship program to encourage medical students go into the field of rheumatology. Two months ago, the University of Arizona was awarded one of those fellowships.
"For undergrad trainees, and for people who want to go into medicine, it does help propel interest," Dr. Wershba says. The goal? Trying to level the playing field for kids like Gwen and Cooper.
There is no cure for pediatric arthritis, the hope is that a child goes into remission. If you want to help, the Arthritis Foundation needs donations and volunteers.
To make a donation: www.walktocurearthritis.org/arizona.