A system of practical medicine. By American authors. Vol. 4

by Unknown

In some cases which, from the character of the urine as well as from the other symptoms, should evidently be classed as diabetes insipidus, the quantity of urine, although somewhat increased, is not very excessive, reaching perhaps two liters, but in the great majority is discharged in much larger quantity. In a case which came under the observation of the writer by the kindness of H. E. Marion the amount of urine gradually rose from two or three gallons to five or six and seven, and on one occasion the patient, a girl of fifteen, after some unusual excitement is supposed to have passed eight gallons in the course of twenty-four hours. Of this eleven quarts was by actual measurement, and passed in the presence of her mother in the course of the afternoon.

The urine in these cases is, as would naturally be supposed, of a very pale color and of low specific gravity, which from 1005 to 1010, representing the usual range, may in extreme cases fall to or even below 1001 as measured by the ordinary urinometer. I have seen no case recorded where the specific gravity of such a urine has been determined by instruments of greater delicacy. Its odor is comparatively faint, but it is somewhat prone to decomposition. The solid constituents are often somewhat increased in the twenty-four hours, especially the urea, which may be present in double the usual amount. This is probably the result of an increased metamorphosis from the passage of so large an amount of water through the tissues.

It is not always true, however, that the solids are increased, and the difference in the amount of destructive metamorphosis taking place in different cases is probably closely connected with the clinical differences which may be observed in regard to the amount of wasting and affection of the general health. The phosphates are frequently increased, as found by Dickenson and Teissier; and such an increase has probably about the same meaning as the increase in urea. In other cases, however, they take part in the general diminution of solids, as in the case of Marion just alluded to, where they were reported as absent, which undoubtedly means simply present in so small amount as to escape the usual clinical tests.

Among the concomitant symptoms the most necessarily and closely connected with the increased discharge of fluid is its increased ingestion, so that the disease has been called polydipsia instead of polyuria, it being assumed that the thirst is the initial and important symptom upon which the diuresis naturally depends. It has been observed in many cases, however, that the quantity of water drunk is very much below that which is passed. In the case last spoken of the water ingested in the form of drink was but a small fraction of the quantity of the urine, so that the patient drank but two or three pints while passing many gallons. In cases where the beginning of the disease has been carefully observed patients have distinctly stated that the increased discharge began before they felt increased thirst. This of course takes no account of the quantity of water contained in solid or semi-solid food. Polyphagia is occasionally seen, as in the oft-quoted case of Trousseau, the terror of restaurant-keepers. So intense is the craving for water that in several instances where attempts have been made to limit its amount the unfortunate patient has drained the chamber-pot. Emaciation is probably connected with increased metamorphosis, as indicated by the increased secretion of urea and phosphates. Dryness of the skin has been frequently noted, and has been said to mark the distinction between polyuria and polydipsia, in the former the skin being dry, and in the latter moist. In one case, however, where copious perspirations were noted, the patient stated positively that the polyuria began a number of days before increased thirst was experienced. In another very extreme case, attended, however, with no wasting, night-sweats occurred. Pruritus has been mentioned as affording another point in the resemblance which undoubtedly exists between the severer cases of this disease and diabetes mellitus. Dyspeptic symptoms have been noted in some cases, and oedema may take place, as in many wasting diseases.

The nervous symptoms are perhaps the most important in the severer cases. In some which have been examined post-mortem distinct nervous lesions have been found, such as the remains of tubercular meningitis, tumors involving the cerebellum, and softening of the floor of the fourth ventricle; in others the patients are known to have been syphilitic.

Severe headache is a symptom of some importance, occurring in a considerable number, but not the majority, of cases. Atrophy of the optic nerve was present in two reported cases, to which the writer can add a third, where failing vision, headache, and emaciation were the principal and earliest phenomena, while at a later period the atrophy was demonstrable by the ophthalmoscope. The polyuria in this case, though marked, was not excessive, and the patient, a young man, after remaining for some years in a condition of chronic invalidism, died. Chronic interstitial nephritis had of course been suspected and sought for, but no evidence of it found beyond the symptoms already stated; neither were there any more definite cerebral symptoms.

Finally, it should be stated that a great many cases of this kind have no marked symptoms at all except the essential one, and so long as they are supplied with a sufficient amount of fluid live in comfort with their single inconvenience.

The diabète phosphatique of Teissier⁹ should be cited in this connection. In only a small proportion of his cases where an excess of phosphates was noted was the quantity of the urine also increased, and in these the symptoms seem as appropriate to the polyuria as to the phosphaturia. It is worthy of note, however, that one series of his cases is connected with disease of the nervous system; another alternates or coexists, as does also diabetes insipidus, with diabetes mellitus; and his fourth class closely resembles, with the exception of the increase of phosphates (if this can be looked upon, after what has been said above of the increase of solid urinary constituents, as an exception at all), the affection last named—i.e. diabetes mellitus. In fact, many of these cases of Teissier read like what would have evidently been called, without a quantitative analysis, simply polyuria or diabetes insipidus.

⁹ Du Diabète phosphatique, par L. S. Teissier, Paris, 1877.

According to Teissier, the presence of an excess of phosphates in the blood is sufficient to determine a polyuria. It is possible that in many cases where a polyuria accompanies phthisis, as noted in many of his cases, the symptom may be really due to actual organic (perhaps amyloid) disease of the kidney.