Case 39 of 40
Memory changes over weeks and focal seizures need assessment for encephalitis
Example case for staff education
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Page 1
Panel 1: Three weeks before admission
New memory problems develop over several weeks.
Celeste: You have asked about that several times today.
Panel 2: Before admission
Short, repeated movements have also begun.
Celeste: His face and arm suddenly move, then it is over.
Panel 3: Day 1
Marked hyponatraemia accompanies the acute deterioration.
Ward doctor Amira: Treat the sodium disturbance carefully and establish the earlier history.
Panel 4: Day 1
Memory and behavioural changes preceded the worst confusion.
Celeste: This did not all begin yesterday.
Panel 5: Day 2
Sodium correction is monitored; neurological observations continue.
Nurse Tom: We will report any new movement or change in responsiveness.
Panel 6: Day 3
The broader syndrome persists.
Harish: Why are you asking me the same things?
Panel 7: Day 3
A stereotyped event is directly observed.
Nurse Tom: That matches the movements his wife described.
Panel 8: Day 3
Subacute memory change and focal events prompt investigation.
Neurologist Mira: We need to assess for an encephalitic or seizure-related illness.
Panel 9: Day 3
MRI shows abnormalities in both medial temporal regions.
Ward doctor Amira: The imaging supports further neurological investigation.
Page 2
Panel 10: Day 3
CSF investigations address infection and inflammation.
Neurologist Mira: We will test for treatable infections as well as other causes.
Panel 11: Day 3
Antiviral treatment begins while infectious encephalitis is assessed.
Nurse Tom: Treatment and investigation are proceeding together.
Panel 12: Day 4
EEG records temporal seizure activity.
Neurologist Mira: We also need to treat and monitor the seizures.
Panel 13: Day 5
The findings are considered together, with alternative causes assessed.
Ward doctor Amira: No single result should carry the whole diagnosis.
Panel 14: Day 6
Specialist treatment is planned while antibody studies continue.
Neurologist Mira: The clinical syndrome supports immune treatment after assessing infection and other alternatives.
Panel 15: Day 9
Paired testing supports LGI1 autoimmune encephalitis in this clinical context.
Ward doctor Amira: The antibody result fits the history, seizures and other findings.
Panel 16: Week 2
Brief seizures stop; confusion and memory problems remain.
Celeste: The movements have gone, but he still forgets our visits.
Panel 17: Week 3
The team monitors response and adverse effects.
Ward doctor Amira: We must follow cognition as well as seizure control.
Panel 18: Week 4
Physical recovery allows rehabilitation to begin.
Occupational therapist Ruth: We will practise with short, repeated instructions.
Page 3
Panel 19: Week 6
Attention improves before the ability to retain new information.
Harish: When did you say we were going home?
Panel 20: Week 6
A correct diagnosis has not produced immediate cognitive recovery.
Ward doctor Amira: Memory and daily function may improve on a different timescale.
Panel 21: Week 8
External prompts help him complete familiar activities.
Occupational therapist Ruth: Use this cue, then check the next step with me.
Panel 22: Month 3
He needs help with medicines and planning the day.
Celeste: We have arranged support rather than expecting him to manage alone.
Panel 23: Month 3
Follow-up considers relapse, seizures, treatment effects and residual impairment.
Neurologist Mira: Tell us about any new change from this stage of recovery.
Panel 24: Month 4
Physical stamina improves; memory difficulty remains.
Harish: I enjoy this, even when I cannot remember yesterday clearly.
Panel 25: Month 5
Repeated assessment guides rehabilitation and support.
Ward doctor Amira: We will compare progress across the things he needs to do.
Panel 26: Month 6
He has not regained his previous independence.
Celeste: He can do more, but still needs someone to help him organise it.
Panel 27: Month 6
The case ends with partial recovery and continuing care.
Harish: I want to keep working on the things I can do.
Sources
- [S17] Jith, A., Mathew, K.A., Narayanan, D. and Jacob, S.M. (2021) ‘CASPR2 positive autoimmune encephalitis presenting as delirium in an alcohol dependent patient: a diagnostic dilemma’, Kerala Journal of Psychiatry, 34(1), pp. 54–56.
- [S18] Bandyopadhyay, S., Sahu, A., Chandra, S.K., Ghosh Dastidar, A. and Pratihar, S. (2026) ‘Autoimmune Encephalitis in Later Life: A Missed Opportunity in Routine Geriatric Care’, Cureus, 18(2), e104404.
- [S20] Yen, L., Leung, M., Kellaher, D.C., Kukoyi, O. and Xiong, G.L. (2011) ‘The Horse With Stripes: A Case of Anti-NMDA Receptor Encephalitis’, Primary Care Companion for CNS Disorders, 13(4), 11l01141.
- [G02] Graus F, Titulaer MJ, Balu R, et al. A clinical approach to diagnosis of autoimmune encephalitis. Lancet Neurology. 2016;15:391–404.
- [G01] National Institute for Health and Care Excellence. Delirium: prevention, diagnosis and management in hospital and long-term care. CG103.
Commentary
Harish’s low sodium level requires treatment, but his symptoms began before the final deterioration. He has had several weeks of new memory difficulty, altered sleep and brief repeated movements. These suggest a wider neurological illness. Continue assessment after correcting sodium rather than assuming the cause has been fully treated.
New focal seizures, MRI abnormalities in both medial temporal regions and memory changes over weeks justify neurological investigation. Cerebrospinal fluid tests assess infection and inflammation, and EEG helps identify the events. Antiviral treatment begins while possible infectious encephalitis is assessed. Paired antibody tests later support LGI1 autoimmune encephalitis when considered with the other findings. An isolated positive blood test does not establish the diagnosis [G02].
The cited reports include confirmed antibody-associated disease and less certain suggestions of autoimmune disease [S17, S18, S20]. Their evidence differs in strength. This teaching example uses a diagnostic sequence with objective supporting findings. Low sodium remains part of Harish’s illness and still needs treatment.
The brief seizures stop before Harish’s memory and daily activities recover. Rehabilitation and review continue over months. At six months, recovery remains incomplete and he has difficulty retaining new information. Review which findings justified the additional investigations. During follow-up, distinguish continuing inflammation, seizures, medicine effects and residual injury. Prolonged delirium alone does not establish autoimmune encephalitis.