[A case of Satoyoshi syndrome with symptoms resembling neuroleptic malignant syndrome]

Satoyoshi syndrome is a rare neurological disorder of unknown etiology characterized by progressive muscle spasms, alopecia, diarrhea and skeletal abnormalities. We here describe a 25-year-old man who developed symptoms similar to neuroleptic malignant syndrome (NMS). He began to have the clinical characteristics of Satoyoshi syndrome at the age of 12 years. He was admitted to hospitals many times with painful muscle spasms and pyrexia in the early stage of the disease. He received steroid pulse therapy and oral prednisone at the age of 19, the extent and frequency of the spells being reduced thereafter. He was admitted to our hospital due to recurrence of his usual muscle spasms. He was treated with midazolam intravenously to relieve severe muscle ache, pain in the left shoulder, and insomnia. About 90 minutes later, he became comatose, with the following manifestations: hyperthermia, low blood pressure, tachycardia, profuse perspiration, acute respiratory failure, and ensuing cardiac arrest. He developed rhabdomyolysis, acute renal failure, hepatic damage, and diffuse intravascular coagulation. Serum creatine kinase level was elevated to 306,910 IU. He died of multiple organ failure 13 days after admission. His symptoms resembled NMS and malignant hyperthermia (MH). None of patients with Satoyoshi syndrome accompanied by NMS or MH have been reported. It remains to be clarified whether midazolam administration induces NMS in Satoyoshi syndrome. Nevertheless, careful attention should be paid when one administers midazolam to patients with this syndrome.