NMDA Encephalitis – The New Encephalitis on the Block!

Question.... Given an aspect of its mechanism of action (decrease in glutamate receptor excitability) would not PHENOBARBITAL be more efficacious for seizures in these patients?

Saw 2 cases of this within a month while a med student back in California 3 yrs ago. We worked with the California encephalitis project and both young females had ovarian teratomas. They also both needed cyclophosphamide which helped with autoimmune B cell activity. The problem with this diagnosis is the confirmation. Took like 2 weeks from some lab (the only one in the country at that time I believe in Colorado or Minnesota.) Both were awesome cases and both recovered well albeit after a prolonged ICU/hospital stay

I saw a case of this about a few years ago. A teenage girl who had gone to a Pink Floyd cover band show and came in the next day saying she felt trippy and kept hearing Pink Floyd songs vibrating in her head. I pulled out 2 gigantic earwax balls and everything improved and sent her home.... until the next day when she came back in with hallucinations and more Pink Floyd. She had a normal head ct and LP. She was sent to psychiatry for a week and ultimately saw a neurologist who eventually diagnosed NMDA encephalitis. Encephalitis was hardly a blip on the radar when I saw her with cerumen impaction.

I had a case about a year ago, had never heard of NMDAe at the time. No clue what it was at the time, but in asking around, it turned out it was the 3rd case in about a year at our facility. Given that no one else had really heard of it outside of out Neuro ICU attending, I think it's probably grossly underdiagnosed. The case I saw was a 20yo girl with what sounded like acute psychosis (auditory hallucinations and bizarre behaviors) 3 days prior, and was actually admitted to a state psych facility where she began to spike a fever and started having orofacial dyskinesias (chewed through the side of her tongue). The astute doc at the psych facility actually suggested NMDAe, thankfully. She ended up getting steroids, IVIG, and I think plasmapheresis as well. She had an ovarian teratoma that was also resected. It took approx 2 weeks to get the CSF diagnosis, but was indeed positive for anti-NMDA receptor Ab. In f/u, i think I saw that she had been on the ventilator for about a month and her total hospital course was approx 2 months. She was pretty debilitated (I want to say she was non-verbal at discharge) for a while but it looks like she's done a good bit better w/ some rehab and time.

I had a case of NMDAe as well. Quite atypical however. This was a 6 y/o AA male! He had initially presented with irritability and nonspecific flu-like symptoms for 1 week prior to developing generalized tonic clonic seizure activity. He was admitted to neuro and was initially treated for new onset seizures with keppra. He had the full neuro/infectious disease w/u and improved slightly but tanked completely when the neuro service put him on Phenobarb. He was on the neuro unit for a month before he was tested for NMDAe which came back positive over a week after that. He was treated with 1 week of high dose steroids and IVIG, but by that point he had pretty much destroyed all of his NMDA receptors (which can take months to regenerate). He improved steadily, but very slowly for the succeeding weeks and was eventually transferred to another facility for rehab. It can take over a year to come back from this thing. I guess this is something to keep in the back of our minds for weird seizure presentations.

The book "Brain on Fire" is awesome. A great patient perspective that speaks to all aspects of what we do.

With the lp results you obtained, why was viral meningitis excluded before the seizures where one would think of more of an encephalitis?

Are you recommending we order anti-nmda on all LP's for ams and seizure or just those patients exhibiting psychotic features?

I read the book Brain on Fire last fall and loved it. It really was interesting to see our work from the patient's perspective, in a case that no one could figure out. I could just feel her frustration through her writing. It made me realize how frustrating it must be for my patients when I can't figure out the cause of their chest pain, abdominal pain, headaches, etc.....

Cannot believe I just saw a case of this! I listened to this segment and I thought I would never see it. I admitted a valedictorian with possible first psychotic break. Don't even know why I did the LP. Took the inpatient team a week to figure it out. +ovarian teratoma. Thank you EMRAP!