A 45-year-old man developed chorea, behavioural changes, moderate amyotrophy and 
polyneuropathy. Hypertrophic cardiomyopathy and increased serum lactate 
dehydrogenase and creatine kinase (CK) were found. Acanthocytes were not 
detected. The absence of XK protein and faintly expressed Kell antigens on 
erythrocytes were found. Genetic test revealed a R133X mutation of the XK gene, 
confirming the McLeod syndrome. After 7 years he suddenly developed delirium 
followed by severe hypoglycaemia, hyperthermia, rhabdomyolysis, hepatic and 
renal failure. Malignant arrhythmia caused death.