My son has a rare illness that falls between the cracks of healthcare coverage, and we've struggled to find a solution

• Our healthcare system divides conditions into physical health concerns, which are "medical" problems, and mental health issues.
• My son has a rare illness that falls between the cracks of physical illness and psychological manifestations.
• Not only does this mean that very few people have any idea how to treat my son, but that treatment falls between the cracks of what insurance will pay for.

My son, who I won't name to give him some privacy, has a rare disorder that crosses the arbitrary boundaries between psychological and physical illness. It's been a costly struggle to find treatment, and our experience shows the shortcomings of the way we approach medical treatment.

My son's disease is called PANDAS, or pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections. It causes children to have tics, obsessive-compulsive disorder, separation anxiety, fears and other symptoms following a strep infection.

Because this disease is caused by a physical mechanism - the immune system mistakenly attacking the brain when the body is exposed to infection - but shows up primarily in psychological symptoms, most medical doctors and psychiatrists are stumped by it.

My son's journey started four years ago with sudden onset throat-clearing tics at age six. The doctor we went to didn't believe in PANDAS.

The tics went away on their own. A year and a half later, as his fears escalated, he started to experience OCD. Then, a sore throat and a cough preceded a sudden plunge into madness.

A variety of expensive treatments

My husband, son, baby daughter, and I happened to be living in Scotland for work at the time, and the UK medical system responded by refusing to test my son for strep and throwing up their hands.

We ended up paying hundreds of dollars to an out-of-network PANDAS specialist in the US, who kindly helped us get antibiotics sent to the UK, and a couple of thousand pounds consulting a nutritionist. My son barely improved. After eight months of homebound misery in the UK, we came back to the US, leaving jobs in the UK behind.

In the US, we decided to get a second opinion, so we went to a prominent children's hospital. Doctors there performed many tests: MRI, lumbar puncture, blood tests.

Thousands of dollars later, paid for by our insurance, we ruled out many scary possibilities. These tests did not rule out PANDAS, but the neurologist said she couldn't believe that a disease could exist unless she could see it in her tests. She sent us off to a psychiatrist.

The psychiatrist recommended an OCD intensive at a children's psychiatric hospital.

Read more: A 24-year old got a mysterious disease where her body attacked her brain - and scientists are learning it's more common than they thought

After two and a half months of hard work at the hospital, he barely made any progress. He tried various drugs that didn't work. The hospital stay cost over a thousand dollars a day, which our insurance covered. But our whole family stayed in hotels near the hospital in Rhode Island for two and a half months, which we had to pay for, now with our finances running on fumes.

Back home in New Jersey, we decided to try the medical route again. He had his tonsils removed, which insurance covered. But our insurance denied a doctor recommended, but "experimental," treatment for PANDAS - intravenous immunoglobulin treatment (IViG). It would have cost $10,000 that we didn't have, so we weren't able to pursue it.

More drastic and difficult measures

This past June, after a year and much suffering, our insurance did approve a more drastic and difficult procedure - plasmapheresis, or the process of filtering the blood to remove antibodies - and we decided to risk it.

On the last day of the treatment, an allergic reaction landed my son in an ambulance and admitted to the hospital through the emergency room.

Our insurance has told us it won't pay for the ambulance ride and the hospital costs. It should all be covered by our health insurance plan, but I will be sorting this out for months to come.

My son is almost 11 and getting better. He is able to go to school about 60% of the time, and his thinking is clearer again. The OCD still has him in a vise grip, but other fears are loosening.

The plasmapheresis seems to be working, though he will likely need another, which, thankfully, is already approved by insurance.

He also needs psychological therapy to help combat his OCD, but guess what? The only people who treat this aren't covered by our insurance, and our son would need to be seen twice a week, at a cost of $200 a visit.

So far, we are going without. We will keep looking, but few mental health professionals accept insurance these days.

One of the hardest parts about my son's illness falling between the cracks of physical and mental health coverage is that none of the specialists who treat PANDAS take insurance.

They can't. They've told me that insurance gives them a hard time about paying their claims and sets ridiculously low limits for charges. Treating this disease requires long visits to get all the history and symptoms straight.

Even the tests to help determine the shape of the illness are not covered. We keep delaying or skipping treatments and tests that aren't covered because we can't afford them.

Read more: 5 mistakes I made when I had my first kid that I wish I could have avoided

But we are some of the lucky few. We have insurance, we have discovered what this mysterious disease is, and we are getting some treatment to get my son better.

I work from home as much as I can, but it is hard, because my son often can't go to school. When he's at his most sick, I can't work at all.

Still, we won't be able to afford all the treatment that my son needs. I want my son to get better. I want the health system to catch us before we fall completely through the cracks - health-wise for my son, and financially for my whole family.

Want to tell us your healthcare story? Email Zach Tracer at ztracer@businessinsider.com.