A 15-year-old boy presented with osmotic symptoms and photopsia. He had short-term memory impairment, visual hallucinations, and headache. His random blood sugar was 474 mg/dl, HbA1c -9.4%, and glutamic acid decarboxylase -65 >2000 IU/ml. Magnetic resonance imaging brain and cerebrospinal fluid study were normal. Digital electroencephalography was suggestive of bilateral hemispheric occipital lobe seizures. He responded well to insulin and antiepileptic medications.
Keywords: Hyperglycemia; occipital lobe seizures; type 1 diabetes mellitus.