A lowered tolerance to carbohydrate, as shown by alimentary and spontaneous glucosuria, has long been a well-recognized symptom of hyperthyroidism, and by many authors regarded as a most important one. Scarcely any two observers agree, however, as to the frequency of its occurrence, and many hypotheses have been advanced to explain its presence in some cases and absence in others.
It was thought that a systematic study of the sugar in the blood concomitantly with that of the urine under uniform conditions might throw some light on this subject, and give us a more accurate knowledge of the frequency and degree of lowered carbohydrate tolerance in this disease. For this reason the present work was undertaken. While it was in progress, Flesch1 reported a series of forty cases of hyperthyroidism with special reference to the concentration of sugar in the blood under various conditions. His results, which are