DIABETES MELLITUS.—True diabetes ; a disease characterised by the excretion of grape-sugar with the urine. Persons in whom the metabolic processes fail to make use of all the sugar and sugar-forming food which they eat, and who excrete part of this sugar with their urine, are designated as diabetic. There are two types of diabetes, a mild and a severe form. In the mild form, sugar is excreted only when sugar or articles closely allied to sugar (particularly starch and flour) are consumed. In the severe form, sugar is excreted independent of the above-mentioned articles of food, and seems to he developed from the proteids of the body. In cases of chronic diabetic disease, there are other chemical changes in the urine ; and such may also occur from inadequate treatment. The sugar contained in the urine is grape-sugar, so called because it was first found in fruits, particularly in grapes. Its fermentation causes the formation of the well-known spirits of wine. This sugar is a normal constituent of the tissue-juices and blood of animals. The remote causes of diabetes are as yet unknown, but it has been discovered that the disease stands in close relation to changes in the pancreas and to various diseases of the nervous system. From a practical standpoint, the question of inheritance is of great importance.
According to statistics, diabetes occurs at present more frequently than formerly, a fact which may, with some justice, be accounted for by the increased demand made upon the nervous system by the modern way of living. The largest number of cases occur after the age of 45 years, and, contrary to most other diseases, the course is then slower and milder than when the disease appears in youth. The disease usually begins insidiously, and almost without exception in a mild form ; if neglected, although some times also in spite of careful treatment, this develops into a severe and dangerous type.
The disorder has many symptoms, which may vary with each case. The most important of these are : Increased thirst, increased quantity of urine, loss in weight, unusual fatigue after exertion, mild and wandering pains in the muscles of the back and in the limbs, nerve pains (particularly in the hips and legs), spasms in the calves at night, diminished sexual desire in man, itching sensation and moist eruptions on the sexual parts of the woman, loosening of the teeth, receding of the gums around the incisors, weakening of the power of sight, and abscesses of the skin (so-called furuncles). These and similar symptoms are not necessarily all present, but
they frequently alternate, one coming and another going. If only one symptom is considered, it frequently happens that the disease is not recog nised, and therefore incorrectly treated. It is therefore necessary, if one of the mentioned symptoms is present, or if there be any other health disturb ance of doubtful origin, to have the urine examined for sugar. The best time for such an examination is three hours after a plentiful meal of bread, milk, and sugar. The night urine must not be taken for this purpose, for frequently it contains no sugar, even if much sugar is excreted during the day. Sugar is often found in the urine of patients who complain of nerve pains which were supposed to have resulted from a simple cold. Early recognition of the disorder is therefore important, firstly, in order to cure the disease if possible, or at least to prevent aggravation of the condition by proper regulation of the mode of living ; and, secondly, because neglect means the development of the severe type of the affection, or the accompaniment of dangerous complications, such as falling out of the teeth, cataract, gangrene of the feet, inflammation of the cellular tissues, arterio sclerosis, and heart weakness. The patient generally succumbs to these complications, or to the increasing weakness, or to a peculiar brain paralysis ; in some cases after one or two years, but more often after the disease has lasted a decade or longer.