A 61 year old african-american woman presents with nausea, vomiting, and confusion for 3 days, which markedly worsened today. There was no history of fever, headache, trauma, or urinary or bowel symptoms.
She was in apparent good health immediately prior to this, with her only comorbidity being type 2 diabetes mellitus for 5 years, which was well controlled on metformin 850 mg twice a day alone.
Her random capillary glucose is 100 mg/dl. Her full blood count, liver function tests, amylase and lipase, urinalysis, ecg, chest x-ray and plain CT brain are found to be normal.