DIABETES MELLITUS.
The urine in this disease contains a sugar which may be regarded as identical with sugar of grapes. It is generally of very high specific gravity, varying from the highest specific gravity observed in health to 1055 or even 1060. • Schonlein has an opinion that in the first stages of diabetes there is albumen in the urine, and that this becomes replaced by sugar. This opinion I scarcely can believe correct. The fact, indeed, could not well have escaped my notice, my attention having been parti cularly directed to the study of albuminaria for some years past. The experiments of Kant have shown that urea is generally ex creted in diabetes mellitus to the same amount as in health in the twenty-four hours. During the progress of the disease I have several times observed the whole of the sugar sud denly disappear from the urine, and its place supplied by an enormous excretion of urea.
I at first was inclined to regard this as a favourable indication, but experience has not confirmed that belief. Uric acid is 'not un commonly present in considerable quantity, and this I believe to be a favourable indication in diabetes. Simon has shown that the ab solute quantity of urea excreted in twenty four hours is occasionally diminished; but the general rule is that the quantity approaches that of health. Caseous matter is sometimes found in diabetic urine, and, when present, it excites rapid fermentation immediately after the urine is voided.
Bouchardat has described a form of sugar which occasionally exists in diabetes, which is insipid, but which corresponds in every other respect with the sweet sugar. Simon says he once met with it.
Lehmann, Ambrosiani, Milner, and Simon have observed the presence of hippuric acid in diabetic urine.