Etiology.—Diabetes occurs most fre quently in middle age, but polyuria is not rare in childhood. In some families several polyurics will be found; these are usually families showing a neuro pathic diathesis.
Case observed in a girl, 16 years old, who suffered from diabetes insipidus, who belonged to a family in which the disease Wai hereditary. Four genera tions and 8 out of 19 members of the family had suffered from polyuria, viz.: the great-grandmother, 3 of ber children, 3 grandchildren, and the great-grand child,—the patient. The disease was, in all cases, directly inherited by the child from its parent, all the first-born being , attacked. The grreat-grandfather suf- I fered from enuresis, hut not from poly nria. Lauritzen (Ilospitalstidende, p. 353, '93).
Study in metabolism on two cases of diabetes insipidus in a man of 47 and l a girl of 14 years showed that they did not eliminate more water in the urine than they ingested; insensible perspira tion was practically normal, contrary to the statements of some. In one case there was a retention of the albumin metabolism and in the other a loss. Di gestive functions were good. Acidity of the urine was high. The elimination of P20, in the aces was normal. In the urine there was a retention on the part of the man and a loss of P,O, on that of the girl. G. Vannini (Berliner klin. Woch., July 16, 1900).
In a certain number of cases the poly uria is referable to a traumatic cause; for instance, a fall upon the head. Some times diabetes mellitus immediately fol lows the traumatism and it is only after a time, two months or more, that it changes to diabetes insipidus. There is, consequently, an undoubted connection between the two affections. This has likewise been proved by experimenta tion. Claude Bernard, in puncturing a certain spot in the floor of the fourth ventricle in a rabbit, caused diabetes mellitus, while in puncturing at a slightly different point, he caused sim ple polyuria.
After traumatism of the cranium the chronic lesions of the encephalon, and tumors, in particular, occupy an impor tant place in the etiology of polyuria. I have seen several cases of this kind. In one of them there was found at the autopsy a tumor of the optic thalamus. The polyuria appeared very suddenly.
Syphilitic lesions of the encephalon are the principal causes of polyuria. The number of such cases is very great.
Finally, simple neuroses frequently bear a relation to this affection.
As already pointed out by the writer, the suprarenal gland contains a sub stance which gives rise to glyeosnria if brought into the circulation in minute doses. This substance is identical with that constituent of the suprarenal which turns solutions of iron green and re duces ammoniacal solution of silver, and which also serves to increase blood pressure. Suprarenin and adrenalin
possess this sugar-producing power. A fraction of a milligramme of this sub stance, or the contents of a single su prarenal gland, serves to give rise in a rabbit to nearly 6 per cent. of dex trose in the urine. In dogs fed exclu sively on meat, 4 per cent. of grape sugar was found in the urine. The gly cosuria persisted for two and three days. By continued injections of supra renal juice true diabetes may be pro duced. The starting-point of the sugar producing agent of the suprarenals the writer believes to be in the liver. Hun gry dogs whose glycosurie power may be regarded as exhausted excrete scarcely any dextrose after injections. but if feil on fat they begin again to give oiT dextrose in large quantity. There is a great probability that the suprarenals have etiological relation to many forms of human diabetes; especially Addison's disease may be due to loss of activity in the suprarenals. F. Blum (Amer. 'Medicine, :May 31, 1902).
Pathology.—As to the pathogenesis, it is not unlikely that primary polyuria— not polydipsia—is caused by paralysis of the vasoconstrictors of the kidney. It is difficult to conceive of a permanent ex citation of the vasodilators. There may likewise be a defect in the normal re sorption of the water, which, as we know, takes place in the normal condition in the tubules; but this mechanism appears rather to be that of the polyuria attend ing interstitial nephritis. The health is naturally much less affected in polyuria than in diabetes mellitus; brut in true polyuria the defective hydration of the tissues is likely to cause certain nervous troubles, which in themselves are of no very great importance.
Treatment.—In neuropathic subjects the general condition should be treated by means of bromide of potassium, vale rian, etc. For the special treatment of the polyuria ergot of rye (or, even better, ergotine) and antipyrine should be used.
The above two remedies, the first named, in particular, have cured the dis ease. I have also obtained some success by the use of the continuous current, the positive pole being placed upon the spinal column, and the negative at the level of the hilum of the kidney.
Small doses of amylene hydrate may in many eases bring about a temporary improvement in the polyuria and poly dipsia and, in a few, a permanent cure. The only drawbacks are the disagreeable taste and insolubility. It can be ordered in Capsules to be followed by a glass of beer or wine. W. Niessen (Then Monats., Aug., 1900).
If the polyuria is dependent upon nervous lesions, the same means are to be employed.