A decade ago, Doug Upton was the picture of strength as a U.S. Marine Corps officer stationed in Jordan.

But in 2016, subtle warning signs emerged, indicating something wasn’t quite right.

“My legs were numb a lot,” Upton, now 34, said. He couldn’t keep up during battalion runs, and he sometimes slipped from ladders that had previously been easy to climb.

He was later diagnosed with relapsing-remitting multiple sclerosis and started immunosuppressive therapy. After retiring from the Marines, he adjusted to life with MS — and eventually stabilized.

Then, in 2022 at age 31, he caught a cold that just wouldn’t go away.

What followed would strip away the Sewickley, Pennsylvania, resident’s memory, mobility and, at times, his sense of self, the result of a rare and often misunderstood condition: autoimmune encephalitis.

The disease can be challenging to diagnose and treat and can manifest with vast difference from person to person. For Upton, the condition required more than three months of hospitalization, followed by an even longer recovery.

Just a few years earlier, Upton ran and finished the Marine Corps Marathon in Washington, D.C. Autoimmune encephalitis left him wondering if he’d ever walk again.

“It was discouraging because you come home and your pants don’t fit. You can’t see, you can’t walk,” Upton remembered. “I honestly didn’t think I was going to run again, because I remember walking and it was such a horrible thing.” He almost resigned himself to believing this was “the new way (life) is going to be.”

Tough to diagnose

At first glance, his monthslong decline looked like infection, stress or possibly a psychiatric illness.

That’s common with autoimmune encephalitis, a condition that can unfold gradually over weeks before erupting into seizures, hallucinations and profound memory loss, explained Kiran Thakur, associate professor of neurology at Columbia University Irving Medical Center.

Because symptoms often mimic other disorders — and nearly half of encephalitis cases lack a confirmed cause — diagnosis can be delayed at a moment when early treatment is critical, she said.

Simply put, encephalitis is an inflammation of the brain, Thakur said. The disease has a “spectrum of causes, and the wide-ranging symptoms include confusion, memory loss, hallucinations, seizures, speech problems and muscle weakness."

In infectious encephalitis — caused by viruses including herpes simplex or West Nile — the onset is often rapid and notable. In just a day or two, a patient can go from completely normal to extreme confusion and actively seizing. It’s not a subtle disease, Thakur said.

Autoimmune encephalitis, on the other hand, can look very different. As a result, it can be quite challenging to diagnose.

“Essentially what happens in autoimmune encephalitis is that this antibody in the immune system kind of gets confused and attacks itself,” Thakur said.

Rather than a sudden crash, patients may decline over the course of a few weeks. They may start feeling a bit off, gradually accumulating symptoms such as fever, headache and weakness.

“Oftentimes with autoimmune encephalitis we see a kind of more indolent course,” she said. Patients progressively feel worse until suddenly more severe symptoms — seizures, memory loss, psychosis, vision changes and more — kick in.

That diagnostic gray zone can delay targeted treatment in a condition where time matters.

Upton’s bout followed a similar trajectory.

By summer 2022, Upton, a native of Slippery Rock, had earned his MBA and was working in Pittsburgh. An enthusiastic amateur runner, he had completed the Marine Corps Marathon in 2019 and continued to run other shorter races since. Then came that stubborn cold.

“I got sick and couldn't fight it,” Upton said. By September, he emailed his boss to request emergency medical leave. His wife, Allison, drove him to the hospital.

From there, his memory fractures.

“I don't remember the first three and a half months,” he said, describing hallucinations during his hospitalization in the neurology section of UPMC Magee Womens Hospital in Oakland, from September through December 2022.

He lost both short- and long-term memory. He couldn’t tell time. He slurred his speech. He couldn’t walk.

“I came home with pinhole vision,” just a tiny slice of sight in the center of his field of vision. He couldn’t turn his head without losing his balance. “I'd fall over, couldn't lift my head, couldn't close my eyes.”

He had to shower sitting down, or he’d take a tumble.

He forgot hobbies. Forgot conversations. For a time, he even forgot he had children. “It was just horrible.”

When he was released from the hospital, his children — ages 2 and 4 — were nervous around him. He couldn’t pick them up and could only sit nearby on the floor to spend time with them.

His diagnosis was never fully definitive — infectious versus autoimmune — but doctors treated him with intravenous immune globulin, or IVIG — a therapeutic, immune-boosting product made from human plasma containing antibodies from thousands of donors, which he still receives. Today, his MS is stable and his brain lesions are unchanged.

Upton's case was particularly complex because of several overlapping factors, Cigdem Isitan-Alkawadri, a UPMC neurologist who treated Upton, said in an email.

Not only is MS an inflammatory neurological disease, Upton was also receiving a treatment for the disease that made him more susceptible to contracting post-infectious encephalitis.

"This overlap made it challenging to clearly distinguish between an infectious cause and a form of autoimmune encephalitis," she said, adding that the "overall pattern of his symptoms, imaging findings, and spinal fluid results" ultimately led the medical team to treat it as autoimmune encephalitis.

Complex cases like Upton's "require a broad diagnostic approach and careful monitoring over time in order to determine the most likely cause and identify the most effective treatment strategy," she said, adding that UPMC has a multidisciplinary autoimmune encephalitis clinic that brings together experts in neuroimmunology, epilepsy and neuropsychiatry. This niche multidisciplinary effort is one of the few in the country, said Isitan-Alkawadri, who is also an assistant professor of neurology at the University of Pittsburgh’s School of Medicine.

Why awareness matters

Advocacy group Encephalitis International has promoted the FLAMES acronym — standing for flu-like symptoms, loss of consciousness, acute headache, memory problems, emotional or behavioral changes, and seizures — to help people recognize the symptoms.

Thakur believes tools like this can save lives.

Awareness campaigns have worked for other neurological emergencies, such as stroke. Patients with autoimmune encephalitis, she said, need similar recognition to ensure rapid diagnosis and treatment.

Because early treatment is essential with encephalitis, doctors often will begin broad therapy — antivirals, antibiotics and steroids — while still awaiting test results.

In autoimmune cases, treatments may include steroids, plasma exchange or IVIG, a blood-derived therapy that helps clear harmful antibodies, Thakur said.

Autoimmune encephalitis is rare. But its effects can be devastating — personality changes, memory loss, psychiatric symptoms, seizures — depending on which brain regions are inflamed.

“We know that patients need a lot of rehab, physical therapy, occupational therapy, cognitive rehab, and that really also is so fundamental in terms of the overall recovery course,” Thakur said. Social support and cognitive rehabilitation are vital.

Rebuilding a life

Recovery, however, was anything but quick.

Upton spent months in intensive rehabilitation: “It was three times a week — speech, occupational, physical therapy, like, bang, bang, bang,” he said.

The exercises felt almost childlike — placing pegs and climbing stairs — but they helped him rebuild his foundation to living.

Tasks like placing items on a shelf or tapping nails in a hole were repeated over and over. “They seem like simple, kiddie stuff,” Upton said. But each time the tasks would become a little easier to complete.

His father-in-law drove him to appointments. His wife managed the household. Friends sent messages of support.

And the Marine Corps training that once helped him endure desert heat now carried him through recovery.

“The grit that you get from the Marine Corps — rough situations and uncomfortable environments — and to be able to maintain your cool and just keep going was very helpful,” he said.

Still, progress was painfully incremental. He started by using a rowing machine for two minutes. Then five. Then 10. He walked a few houses down the street, then farther each day.

“I honestly didn't think I was gonna run again,” he said. At the start of his recovery, walking felt so unnatural that he assumed the feeling would be permanent.

His rehabilitation doctor, at UPMC Rehabilitation Institute in McCandless, insisted on patience when Upton was eager to return to work as a technology management consultant.

“When I finally did go back … you go back to work for one day, for one hour,” he said. “Just take it slow and take your time and focus on recovery, because don't rush yourself.”

Recovery from encephalitis varies significantly from person to person, Isitan-Alkawadri said. For Upton, "one encouraging factor was that he responded well to treatment with intravenous immunoglobulin, or IVIG," she said.

Additionally, "his active engagement in rehabilitation also played an important role, and with continued therapy he was able to gradually return to his baseline level of functioning."

This past fall, Upton again toed the starting line of the Marine Corps Marathon — the first time he had run that distance since autoimmune encephalitis had knocked his feet from under him.

“It was a good validation to kind of be back to normal.”

Today, Upton lifts weights again. He works full time. He is preparing for the birth of his fourth child.

He doesn’t claim expertise. But he does offer advice to others facing the same frightening road.

“It's going to be a very long, arduous road, but just take it day by day,” he said. “Just trust the process.”

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