For more than two decades, a Saskatoon woman believed she was living with Multiple Sclerosis. Just over a year ago, she found out she'd been misdiagnosed with the disease.

When she was 21 years old, Jackie Pilon was diagnosed with MS after she'd had an issue with vision in her right eye followed by encephalitis, an inflammation of the brain. It was April 1992, and she said it was a difficult prognosis to live with.

"I was about to get married, and I was basically told that having children would probably not be a good idea for me, and my husband would probably become my caregiver before long," she said.

Taking the medical condition into consideration, Pilon changed her career aspirations. But she was willing to tackle life head on and decided, along with her husband, to have children.

"When they first mentioned it, quite honestly, I was in disbelief because for so many years, over half my life, I was living with an illness called MS." - Jackie Pilon 

MS is a difficult disease to diagnose and symptoms vary. Pilon was diagnosed as relapsing-remitting which is characterized by unpredictable relapses followed by periods of months or even years without symptoms.

Pilon said over the years she experienced numbness or tingling, which at the time was connected to the diagnosis, but in hindsight could have been pinched nerves or related to anxiety.

The family ended up living in New York while Pilon's husband played in the NHL, and she was prescribed a medication only approved in the U.S.

"They didn't see a need to re-evaluate at the time and the medication; there were no side effects," Pilon said.

For 17 years Pilon stayed on the medication, which required injections, only going off while pregnant with her children.

A year ago, while getting treated for migraines, Pilon got an MRI and her neurologist said he wasn't detecting any of the signs that should be present for MS.

"When they first mentioned it, quite honestly, I was in disbelief because for so many years, over half my life, I was living with an illness called MS. And it was one of those things that partially defines you," she said.

Pilon had actually been living with Acute Disseminated Encephalomyelitis, which does carry some of the same symptoms as MS but is not as serious a diagnosis. Pilon said there were many opportunities for experts to re-evaluate her condition but since, at the time, the medication appeared to be working it wasn't a consideration.

Learning the new diagnosis has been a journey, she said.

"It was anger at the first diagnosis, of missed opportunities. But then it became the missed opportunities brought me where I am here, and I think I'm a pretty good person right now. So if it wasn't for this I don't know who I would be," she said.

"The biggest acceptance, I think, is just time. It's just taken me a while to really be able to say it out loud that this is happening and this is real."

MS difficult to diagnose

The misdiagnosis of Pilon's MS, while difficult, isn't that surprising, according to Dr. Micheal Howard-Tripp with the College of Physicians and Surgeons of Saskatchewan.

"Some people are diagnosed with MS and hardly have any symptoms throughout their lifetime; others have a rapidly progressive disease where they develop symptoms very quickly," he said.

Dr. Micheal Howard-Tripp

Dr. Micheal Howard-Tripp with the College of Physicians and Surgeons of Saskatchewan says MS is hard to diagnose. (CBC)

Howard-Tripp said in the two decades since the original diagnosis, the state of medical knowledge, particularly surrounding MS, has changed. But he added that even today, the diagnosis of the disease is not straight forward.

"There is no definitive test that you can do that says this patient has MS [or] this Patient doesn't have MS," he said.

Diagnosis is essentially an art and a science. Howard-Tripp said when physicians see a patient they take a history, explore signs and symptoms, then do a differential diagnosis. That means a doctor takes the most likely diagnoses and runs tests to confirm or refute them.

"Even despite that, you end up with one or two diagnoses that are most likely," he said.

Howard-Tripp said that doctors can "anchor" to a diagnosis and may not explore it further. He suggested patients have conversations with their doctors if new symptoms persist or if there is concern of a misdiagnosis.  

Pilon said she has no regrets or animosity, just advice. She said people should stay proactive in their own health and do research into any diagnosis.