Anti LGI1 Encephalitis
Description
● Occurrence:
➣first mentioned in or around 2010.
➣ Case reports and series are now recorded all over the world.
➣For instance, in a Japanese case from 2024, a patient was diagnosed with anti-LGI1 encephalitis after being brought to psychiatry with anxiety, panic, and psychosis.
➣Middle-aged to older individuals are usually affected (median ~60 years, although variation is broad).
● Overview / Cases Found
➣Key symptoms include seizures, disorientation, and memory loss due to limbic encephalitis.
➣Neurological aspects may be preceded by psychiatric manifestations, such as anxiety, mood swings, psychosis, and personality abnormalities.
➣Fasciobrachial dystonic seizures (FBDS) are a hallmark symptom that is sometimes misdiagnosed as tics or behavioural problems. They are very short.
➣Approximately 60% of individuals experience hyponatraemia as a result of SIADH.
➣Although tumour connection is rare, there is still a slight chance of an underlying malignancy, unlike anti-NMDAR encephalitis.
● Medical Management
➣Obstacles that physicians encounter:
1. Diagnostic delay: antibody testing is delayed by the initial mental diagnosis.
2. Misidentification of seizures: FBDS are frequently disregarded.
3. Relapse risk: prompt identification is necessary for effective early aggressive therapy to improve results.
4. Electrolyte instability: Hyponatraemia might complicate presentation by causing disorientation or seizures.
● How they managed:
➣Diagnosis: anti-LGI1 antibody tests in serum and CSF, EEG, and MRI (mesial temporal lobe hyperintensities).
➣First-line treatment:
➣high corticosteroid dosage.
the exchange of plasma or IV immunoglobulin (IVIg). ➣Rituximab or cyclophosphamide, if refractory, is the second-line therapy.
➣Antiepileptic medications are used to treat seizures, however immunotherapy frequently works better than AEDs alone.
➣ Supportive care: control hyponatraemia with salt tablets, hydration restriction, and vaptans if severe.
➣Relapse prevention measures include long-term monitoring and a gradual immunotherapy taper.
Protocol
➣Challenges nurses face:
•It might be challenging to distinguish early symptoms like agitation, panic, psychosis, and sleeplessness from a fundamental mental illness.
• Seizures are common during admission (perhaps hundreds each day in FBDS), and it might be challenging to identify mild seizures.
• Electrolyte imbalances: frequent hyponatraemia need close observation.
• Families that experience abrupt behavioural and cognitive deterioration are experiencing emotional anguish.
• Side effects of immunotherapy and steroids (hyperglycemia, infection risk, mood changes) are a burden of treatment.
●How nurses managed it:
1. Safety and observation:
• measures to avoid seizures (fall prevention, bed cushioning).
• learning to identify short-lived FBDS bouts.
• regular or ongoing neurochecks.
2. Management of electrolytes:
•Frequent serum sodium tests, fluid balance, and daily weights.
•teaching the patient and their family about SIADH and the value of fluid restriction.
3. Assistance with medication:
•Keep an eye on the adverse effects of steroids (blood pressure, blood sugar, infection symptoms, mood swings).
•Make sure that immunotherapy schedules (IVIg infusions, plasmapheresis sessions) are followed.
•Record the frequency of seizures and the response to therapy.
4. Treatment of mental symptoms:
•calm setting, assurance, and de-escalation methods.
•Working along with psychiatry to modify medications (to prevent oversedation).
5. Support and education for families:
•Describe how the sickness is autoimmune rather than "purely psychiatric."
•Offer materials on long-term management and relapse indicators.
6. Coordination between disciplines:
•Collaborate closely with immunology, neurology, psychiatry, and endocrinology (for SIADH).
Notes
Numazawa T, et al. Anti-LGI1 encephalitis preceded by psychiatric symptoms: a case report. (Japan, 2024).
van Sonderen A, et al. Clinical profile and long-term prognosis of LGI1 antibody encephalitis: a multicentre study. Lancet Neurology, 2016.
Dalmau J, Graus F. Autoimmune encephalitis update. Lancet Neurol. 2018.
