[Cerebral infarction and high serum levels of muscle-derived enzymes associated with abrupt increase in hematocrit in a patient with secondary erythrocytosis].

A 70-year-old man was admitted to our hospital because of fever and progressive dyspnea in December 1989. He was already diagnosed as having erythrocytosis secondary to pulmonary fibrosis 4 years previously and the values of his hematocrit (Ht) were maintained between 44.5 and 62.9% by repeated phlebotomy. Immediately after admission, severe diarrhea developed and the Ht value was 61.5%. Around 1:30 a.m. of the 3rd hospital day, he developed disturbance of consciousness. In addition, the serum levels of LDH, CPK, aldolase, and myoglobin of muscle origin increased markedly and the Ht value showed 78.5%. While the level of consciousness was gradually restored by 600 ml phlebotomy and 1,500 ml saline infusion, dysarthria and hemiplegia became evident. The Ht value early in the morning of the 3rd hospital day was reduced to 59.4%. Although cranial CT and MRI performed 74 days and 15 months, respectively, after the onset of the symptoms failed to reveal any abnormal shadow, he was clinically suspected to have cerebral infarction. These findings emphasize that abrupt increase in Ht or blood viscosity is a possible factor triggering cerebral infarction, and adequate control of Ht value is recommended for the prevention of such a condition in the aged.