Case Presentation and Discussion
A 27 year-old male with a history of non-insulin-dependent type 2 diabetes (HbA1c 13.9%) presented with several weeks of right-sided headaches and visual abnormalities including achromatopsia and macropsia. Admission labs demonstrated hyponatremia to 132 mmol/L, a normal anion gap, and an elevated serum glucose of 345 mg/dL. MRI demonstrated confluent T2-FLAIR hypointense signal in the right temporo-occipital white matter and subtle cortical diffusion restriction in the right occipital lobe (Figures 1-3). The patient was diagnosed with non-ketotic hyperglycemic seizures based on the imaging findings. His symptoms improved with normalization of serum glucose levels and initiation of levetiracetam.
Figure 1.
Axial FLAIR shows hypointense signal in the temporo-occipital white matter.
Figure 2.
Coronal T2 shows hypointense signal in the temporo-occipital white matter.
Figure 3.
Axial DWI shows subtle cortical diffusion restriction in the right occipital lobe.
Partial seizures are a known complication of hyperglycemia, and occur more commonly in non-ketotic hyperglycemia than in diabetic ketoacidosis. The pathophysiology is likely multifactorial, with increased metabolism of GABA as well as hyponatremia thought to be factors in reducing the seizure threshold. 1 The T2 hypointense signal may result from free radical accumulation and iron deposition in the setting of excitotoxic axonal damage, although this is incompletely understood. 2 Previous case reports have demonstrated similar presentations in older patients (>50 years) with very elevated serum glucose levels (generally >400 mg/dL).3–5 We present a case of non-ketotic hyperglycemic seizures with classic confluent T2-FLAIR hypointense white matter signal in a young patient with a relatively low serum glucose and mild hyponatremia.
Footnotes
Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
ORCID iD
Alex S. Hong https://orcid.org/0000-0002-3334-5035
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