[An elderly patient with symptoms of dehydration].

In connection with serious dehydration symptoms in an elderly patient, which appeared to be attributable to a hypersmolar nonketoacidotic diabetic syndrome, a comprehensive study of this syndrome is made with reference to a study of pertinent literature. Possible causes, pathogenesis, clinic and treatment are extensively dealt with. The seriousness of this clinical picture, the high rate of mortality and the favourable prognosis if immediate action is taken are pointed out.