Patient handout

Other Autoimmune Encephalitis (surface + intracellular AB)

PRODUCTION

1. Your condition

This handout is for other autoimmune encephalitis (surface + intracellular ab). Your care team identified this based on: caspr2 morvan syndrome: neuromyotonia + insomnia + amnesia + dysautonomia tetrad (pmid 20663977).

Other reasons your team may use this plan: gaba-b receptor encephalitis: refractory status epilepticus + early-onset seizures + paraneoplastic sclc ~60% (graus 2016 pmid 26906964); ampa receptor encephalitis: limbic + psychosis; paraneoplastic sclc / breast / thymoma ~70%; dppx (perm-like): cns hyperexcitability + severe diarrhea + tremor + weight loss; rare.

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
methylprednisolone	1 g IV daily × 5 d	IV	daily × 5 d	First-line acute pulse for surface AB; Graus 2016 PMID 26906964
IVIG	0.4 g/kg/day × 5 d (2 g/kg total)	IV	daily × 5 d	First-line combo with steroid
plasmapheresis (PLEX)	5 cycles q48h	IV/large-bore	q2 days × 5	Alternative to IVIG for severe presentation
prednisone	60 mg PO daily × 2-4 wk then slow taper over 6-12 mo	PO	daily slow taper	Maintenance after IV pulse; slow taper to prevent relapse

Plan: AE-other surface vs intracellular AB treatment — surface immunotherapy priority; intracellular cancer-directed priority + immunotherapy adjunct (Graus 2016 PMID 26906964; Honnorat 2018 PMID 17480225)

3. When to call your provider

Contact your care team if any of the following happen:

Breakthrough symptoms on DMT → escalate (rituximab / cyclophosphamide)
Cancer recurrence → onc urgent + neuro coordination
New neurological deficit → ED + repeat workup
IgG <500 → IVIG / pause rituximab
Severe depression / suicidality → urgent psych

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

CASPR2 Morvan syndrome: neuromyotonia + insomnia + amnesia + dysautonomia tetrad; thymoma ~20%; younger male predominance (PMID 20663977)
GABA-B receptor encephalitis: refractory status epilepticus + paraneoplastic SCLC ~60% — both engines apply (neuro.status-epilepticus.core.v1)(life-threatening)
AMPA receptor encephalitis: limbic + psychosis; paraneoplastic SCLC / breast / thymoma ~70%
DPPX PERM-like: CNS hyperexcitability + severe diarrhea + tremor + profound weight loss; rare
mGluR5 Ophelia syndrome: limbic encephalitis + psychiatric + Hodgkin lymphoma paraneoplastic
IgLON5: parasomnia + sleep-disordered breathing + parkinsonism + bulbar features + chorea + tauopathy; HLA-DRB1*10:01+DQB1*05:01 (PMID 28381508)
Anti-Hu paraneoplastic SCLC ~80%: sensory neuronopathy + brainstem + cerebellum + limbic; INTRACELLULAR — cancer-directed PRIORITY (Honnorat 2018 PMID 17480225)
Anti-Ma2 paraneoplastic testicular germ cell (young men) / lung (older): diencephalic + brainstem + hypothalamic + sleep disorders; INTRACELLULAR — cancer-directed PRIORITY
Anti-Ri paraneoplastic breast / SCLC: opsoclonus-myoclonus + brainstem (OMR spectrum); INTRACELLULAR — cancer-directed PRIORITY
Anti-CV2/CRMP5 SCLC / thymoma: chorea + optic neuritis + sensorimotor + uveitis; INTRACELLULAR — cancer-directed PRIORITY
No improvement at 4 wk on first-line steroid + IVIG + PLEX (surface AB) → second-line rituximab + cyclophosphamide
Intracellular AB (Hu/Ma2/Ri/CV2-CRMP5) — antibodies are markers; T-cell mediated pathology; CANCER-DIRECTED THERAPY IS PRIORITY (chemo + surgery + radiation per cancer type); immunotherapy adjunct (Honnorat 2018 PMID 17480225)

5. Follow-up

Long-term coordination — neurology + oncology + sleep medicine for IgLON5 + neuropsych + cognitive rehab; PHQ-9 + cognitive battery at 3 + 6 + 12 + 24 mo; cancer surveillance long-term; AED management; pre-DMT vaccinations; goals of care discussion if intracellular AB + advanced cancer + poor prognosis

6. Sources

Guideline: Graus 2016 IRCNS Position Paper Autoimmune Encephalitis Criteria + Honnorat 2018 Lancet Neurol Paraneoplastic Neurological Syndromes + NEJM 2018 AE review + IgLON5 + CASPR2 Morvan + intracellular paraneoplastic 2020