Nearly three centuries ago Thomas Willis observed the urine from a diabetic patient to be "wonderfully sweet, as if imbued with honey or sugar." Ever since then glycosuria has been of paramount interest to the clinician, for it has become synonymous with diabetes mellitus. However, glycosuria may be due to factors that have no relation to diabetes (e. g., "renal glycosuria"), while, conversely, diabetes may exist in the aglycosuric patient (e. g., in the presence of severe nephrosclerosis). Furthermore, there is a possibility that glycosuria alone is not an index of the severity of diabetes. Hence, controversies exist in the literature concerning the significance of transient glycosuria, the significance of glycosuria associated with a normal blood sugar level and the relative importance of the blood sugar level as compared with the amount of sugar excreted in the urine.
Recent studies in renal physiology have provided information that should clarify some