Simultaneous occurrence of diabetic ketoacidosis, thyroid storm, and multiple cerebral infarctions due to Moyamoya disease.

Diabetic ketoacidosis (DKA) is one of the precipitating factors that can evoke a thyroid storm. Thyroid storm may cause cerebral ischemia in Moyamoya disease, which can coexist in patients with Graves' disease. A 16-year-old girl complaining of dizziness and palpitations visited the emergency department and was diagnosed with DKA combined with hyperthyroidism. A thyroid storm occurred 6 h after the start of DKA management. Her Burch and Wartofsky score was 65 points. Right hemiplegia developed during the thyroid storm, and brain magnetic resonance (MR) diffusion-weighted images revealed multiple acute infarcts in both hemispheres. MR angiography showed stenosis of both distal internal carotid arteries and both M1 portions of the middle cerebral arteries, consistent with Moyamoya disease. After acute management for the thyroid storm with methimazole, Lugol solution and hydrocortisone, the patient's neurological symptoms completely resolved within 1 month, and free T4 level normalized within 2 months. Thyroid storm may trigger cerebral ischemia in Moyamoya disease and lead to rapid progression of cerebrovascular occlusive disease. As a simultaneous occurrence of DKA, thyroid storm and cerebrovascular accident in Moyamoya disease highly elevates morbidity and mortality, prompt recognition and management are critical to save the patient's life.