Hyperosmolar hyperglycaemic state causing atypical status epilepticus with hippocampal involvement

Area of Science:

• Neurology
• Endocrinology
• Epileptology

Background:

• Diabetes mellitus can lead to hyperglycaemic hyperosmolar state (HHS), a serious condition.
• HHS can cause neurological complications like coma and seizures, typically resolving with metabolic correction.
• Unresponsiveness in HHS may indicate underlying subclinical epileptiform activity.

Purpose of the Study:

• To describe an unusual case of non-convulsive status epilepticus (NCSE) in an elderly woman with HHS.
• To highlight the risk of hippocampal involvement and subsequent epilepsy in such cases.
• To emphasize the importance of considering NCSE in unresponsive HHS patients.

Main Methods:

• Case report of an elderly woman presenting with HHS and unresponsiveness.
• Clinical evaluation, electroencephalography (EEG) to detect epileptiform discharges.
• Neuroimaging to assess hippocampal involvement.
• Follow-up with antiseizure medication (ASM) and assessment of seizure recurrence and hippocampal sclerosis.

Main Results:

• The patient experienced NCSE originating from the mesial temporal lobe with selective hippocampal involvement.
• Despite initial treatment for HHS, she remained unresponsive due to NCSE.
• Recurrence of seizures after ASM discontinuation led to hippocampal sclerosis.
• She eventually became seizure-free with continued ASM treatment.

Conclusions:

• Unresponsiveness in HHS may be a sign of subclinical NCSE.
• NCSE in HHS can lead to progressive hippocampal damage and potentially long-term epilepsy.
• Early detection and management of NCSE are vital to prevent permanent neurological sequelae in HHS patients.