[A case of possible neuro-Sweet disease with prolonged disturbance of consciousness and no dermal lesion during the course of dementia].

The patient was a 58-year-old man with 1-year history of cognitive decline, which was diagnosed as Alzheimer's disease in another hospital. He was admitted to our hospital for extreme fatigue, weight loss, and dysphagia, subsequent to the left peripheral facial paresis. Brain magnetic resonance (MR) imaging showed bilateral diffuse white matter lesions and hippocampal atrophy. After admission, he presented with sudden high fever, recurrent exacerbations of consciousness, and increased C-reactive protein level with marked neutrophilia, with the result that he underwent mechanical ventilation. Routine cerebrospinal fluid findings at the exacerbation were normal i.e. 4.7 cells/mm(3), 40 mg/dl of protein, but IL-6 concentration was mildly elevated to 22.2 pg/ml. After confirming the positivity of HLA (human leukocyte antigen) B54 and Cw1, we administered steroid to him and his physical activity and state of consciousness significantly improved. During the course of treatment, dermal lesion characterisitic of Sweet disease was absent. We diagnosed this case was possible neuroSweet disease proposed by Hisanaga in 2005.