A 79-year-old woman who had diabetes mellitus for 22 years developed coma 1 day after influenza A virus infection. Diabetic ketoacidosis (DKA) was diagnosed based on high serum glucose levels (902 mg/dL), an arterial pH of 7.19 and large urine ketone (3 + ). Subsequently, the patient was treated with insulin and fluid therapy. After improvement in serum glucose levels, diffusion-weighted magnetic resonance imaging (MRI) showed acute infarction in the bilateral middle and posterior cerebral artery territories (Fig. 1). No severe stenosis in major cerebral arteries on magnetic resonance angiography was detected. Transthoracic and transesophageal echocardiography did not show any potential cardiac source of embolism including patent foramen ovale or thrombi in the left ventricle.
In the present patient, brain lesions on MRI were located in the white matter, but not in cortices, suggesting microcirculatory impairment by hyperglycemia-induced hypercoagulability and/or hyperviscosity. DKA is associated with thrombotic risks, such as abnormalities in coagulation factors, platelet activation and blood volume, and cerebral edema as a result of DKA might predispose to stroke; however, DKA associated with stroke is rare in adults.