What happens when your immune system hijacks your brain

鈥淢y year of unraveling鈥� is how a despairing Christy Morrill described nightmarish months when his hijacked his brain.

What鈥檚 called autoimmune encephalitis attacks the organ that makes us 鈥渦s,鈥� and it can appear out of the blue.

Morrill went for a bike ride with friends along the California coast, stopping for lunch, and they noticed nothing wrong. Neither did Morrill until his wife asked how it went 鈥� and he’d forgotten. Morrill would get worse before he got better. 鈥淯nhinged鈥� and 鈥渇ighting to see light,鈥� he wrote as delusions set in and holes in his memory grew.

Of all the ways our and damage the body instead of protecting it, autoimmune encephalitis is one of the most unfathomable. Seemingly healthy people abruptly spiral with confusion, memory loss, seizures, even psychosis.

But doctors are getting better at identifying it, thanks to discoveries of a growing list of the rogue antibodies responsible that, if found in blood and spinal fluid, aid diagnosis. Every year new culprit , said Dr. Sam Horng, a neurologist at Mount Sinai Health System in New York who has cared for patients with multiple forms of this mysterious disease.

And while involves general ways to fight the inflammation, two major clinical trials are underway aiming for more targeted therapy.

Still, it’s tricky. Symptoms can be mistaken for psychiatric or other neurologic disorders, delaying proper treatment.

鈥淲hen someone鈥檚 having new changes in their mental status, they鈥檙e worsening and if there鈥檚 sort of like a bizarre quality to it, that鈥檚 something that kind of tips our suspicion,鈥� Horng said. 鈥淚t鈥檚 important not to miss a treatable condition.鈥�

With early diagnosis and care, some patients fully recover. Others like Morrill recover normal daily functioning but grapple with some lasting damage 鈥� in his case, lost decades of 鈥渁utobiographical鈥� memories. This 72-year-old literature major can still spout facts and figures learned long ago, and he makes new memories every day. But even family photos can鈥檛 help him recall pivotal moments in his own life.

鈥淚 remember 鈥楿lysses鈥� is published in Paris in 1922 at Sylvia Beach鈥檚 bookstore. Why do I remember that, which is of no use to me anymore, and yet I can鈥檛 remember my son鈥檚 wedding?鈥� Morrill wonders.

Inflaming the brain

Encephalitis means the brain is inflamed and symptoms can vary from mild to life-threatening. Infections are a common cause, typically requiring treatment of the underlying virus or bacteria. But when that’s ruled out, an autoimmune cause has to be considered, Horng said, especially when symptoms arise suddenly.

The umbrella term autoimmune encephalitis covers a group of diseases with weird-sounding names based on the antibody fueling it, such as anti-NMDA receptor encephalitis.

While they’re not new diseases, that one got a name in 2007 when Dr. Josep Dalmau, then at the University of Pennsylvania, discovered the first culprit antibody, sparking a hunt for more.

That anti-NMDA receptor encephalitis tends to strike younger women and, one of the bizarre factors, it鈥檚 sometimes triggered by an ovarian 鈥渄ermoid鈥� cyst.

How? That type of cyst has similarities to some brain tissue, Horng explained. The immune system can develop antibodies recognizing certain proteins from the growth. If those antibodies get into the brain, they can mistakenly target NMDA receptors on healthy brain cells, sparking personality and behavior changes that can include hallucinations.

Different antibodies create different problems depending if they mostly hit memory and mood areas in the brain, or sensory and movement regions.

Altogether, 鈥渇acets of personhood seem to be impaired,” Horng said.

Therapies include filtering harmful antibodies out of patients’ blood, infusing healthy ones, and high-dose steroids to calm inflammation.

Stealth attack on the brain

Those cyst-related antibodies stealthily attacked Kiara Alexander in Charlotte, North Carolina, who鈥檇 never heard of the brain illness. She鈥檇 brushed off some oddities 鈥� a little forgetfulness, zoning out a few minutes 鈥� until she found herself in an ambulance because of a seizure.

Maybe dehydration, the first hospital concluded. At a second hospital after a second seizure, a doctor recognized the possible signs, ordering a spinal tap that found the culprit antibodies.

As Alexander’s treatment began, other symptoms ramped up. She has little clear memory of the monthlong hospital stay: 鈥淭hey said I would just wake up screaming. What I could remember, it was like a nightmare, like the devil trying to catch me.鈥�

Later Alexander would ask about her 9-year-old daughter and when she could go home 鈥� only to forget the answer and ask again.

Alexander feels lucky she was diagnosed quickly, and she got the ovarian cyst removed. But it took over a year to fully recover and return to work full time.

What could cause memories to vanish?

In San Carlos, California, in early 2020, it was taking months to determine what caused Morrill’s sudden memory problem. He remembered facts and spoke eloquently but was losing recall of personal events, a weird combination that prompted Dr. Michael Cohen, a neurologist at Sutter Health, to send him for more specialized testing.

鈥淚t鈥檚 very unusual, I mean extremely unusual, to just complain of a problem with autobiographical memory,鈥� Cohen said. 鈥淥ne has to think about unusual disorders.鈥�

Meanwhile Morrill鈥檚 wife, Karen, thought she鈥檇 detected subtle seizures 鈥� and one finally happened in front of another doctor, helping spur a spinal tap and diagnosis of LGI1-antibody encephalitis.

It鈥檚 a type most common in men over age 50. Those rogue antibodies disrupt how neurons signal each other, and MRI scans showed they鈥檇 targeted a key memory center.

By then Morrill, who鈥檇 spent retirement guiding kayak tours, could no longer safely get on the water. He鈥檇 quit reading and as his treatments changed, he鈥檇 get agitated with scary delusions.

鈥淚 lost total mental capacity and fell apart,鈥� Morrill describes it.

He used haiku to make sense of the incomprehensible, and months into treatment finally wondered if the 鈥渕eds coursing through me鈥� really were 鈥渄ousing the fire. Rays of hope?鈥�

A growing list of culprits

The nonprofit patient advocacy group lists about two dozen antibodies 鈥� and counting 鈥� known to play a role in these brain illnesses so far.

, offered at major medical centers around the country, are testing two drugs now used for other autoimmune diseases to see if tamping down antibody production can ease encephalitis.

More awareness of these rare diseases is critical, said North Carolina’s Alexander, who sought out fellow patients. 鈥淭hat’s a terrible feeling, feeling like you’re alone.鈥�

As for Morrill, five years later he still grieves decades of lost memories: family gatherings, a year spent studying in Scotland, the travel with his wife.

But he鈥檚 making new memories with grandkids, is back outdoors 鈥� and leads an AE Alliance support group, using his haiku to illustrate the journey from his 鈥渦nraveling鈥� to 鈥渢he present is what I have, daybreaks and sunsets鈥� to, finally, 鈥淚 can sustain hope.鈥�

鈥淚鈥檓 reentering some real time of fun, joy,鈥� Morrill said. 鈥淚 wasn鈥檛 shooting for that. I just wanted to be alive.鈥�

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