V. METHODS OF CLINICAL DIAGNOSIS There are a number of methods used in the clinical diagnosis of the different forms of diseases of nutrition, of a general character. There fore we will take up these before speaking of the individual types of dis ease which we have set forth above. Of course only such methods are meant as can be employed without complicated apparatus, and without too much loss of time, and the use of which will be of actual assistance in the diagnosis of the diseases of nutrition. These method.s are to some extent those in general use in the practice of medicine; to some extent they are methods modified to correspond with the conditions of early childhood, and to the least extent are they adapted only to diseases of this period of life.
The regular observation of the body weight is one of the most important and valuable nwans of assistance in judging the course and severity of diseases of nutrition, as well as the results of the therapeutic measures employed. Weighing should be done every day in acute cases, at the same hour, and in chronic cases at least twice a week.
The above prececlure is a certain standard of measurement. Less certain are the various methods of milk examination in use clinically. Certain gross faults of breast-milk can be diagnosed macroscopically. A watery appearance of the milk, or the fact that the drops pressed out of the breast during or after nursing are thin, almost transparent, and do not adhere to the nipple, point to deficiency in fat and other constituents (Epstein). A diffuse light yellow color, or the appearance of yellowish streaks in the expressed milk drops render probable an admixture of colostrum.
The microscopic examination of breast-milk, which was exten sively employed by Fleisehmann, and recently highly recommended by Friedmann, is only of value in so far as it verifies the presence of colos trum corpuscles or pus cells, which the macroscopic examination has already made probable (Biedert-Winter, Epstein). The estimation of the number of fat globules in the field of view, and their relative sizes has little value. At most, preponderance of the smallest fat globules is useful as a sign of a poor breast-milk.
Also the different lactoscopes, of which there are a great many of different construction, nre only useful in recognizing the grossest bad qualities of breast-milk, and accomplish no more than the naked eye.
Uniikoff's reaction for testing the age of milk in the sense of the duration of lactation in the nurse, is of little value. It consists in adding
to 5 c.c. of milk 2.5 c.c. of a 10 per cent, solution of ammonia, and awaiting the appearance of a rose color. It is not reliable in practice, as Brudzinski, who found it in the 12th and 14th months of lactation, has shown.
The same is true of Storch's reaction, which depends on the fact that raw milk breaks up hydrogen peroxide into water and free oxygen, the latter being recognized by the appearance of a blue color on the addition of paraphenylendiamin. Thiemich, by thorough researches, has disproved the supposition of Nordheim, that this method is of value in explaining certain cases of failure of a child to thrive at its mother's breast.
Thus we cannot rely upon any of the methods mentioned above, and will not assign to them any important role among diagnostic criteria.
It is the same \vith the simple clinical methods of testing eow's milk. One of the most recent is the examination of market milk in cover-glass preparations, advanced by Petruschky and Kriebel. Its value has been repeatedly confirmed (llabinowitsch, Beek, Piorkowski). The procedure consists in drying a drop of milk on a slide, fixation in the flame, removal of the fat with ether, and staining by Gram's method, and its simplicity permits its wide use.
Examination, with the stomach tnbe, which Epstein introduced into pediatrics, teaches us about a number of deviations from the normal course of gastric digestion. The procedure, of which we will take up the details in speaking of therapeutics, is extremely simple. It enables us in the first place to judge of the motility of the stomach. Normally the stomach should be found empty 11 to 2 hours after the taking of food, in naturally nourished infants, and at most 3 hours after in the artificially nourished (Epstein, Cassel, Szydlowski, et al.). Every devi ation from the normal signifies a diminution in the gastric motility-. In the second place the use of the tube makes possible the recognition of mucus, the testing of the reaction of the gastric juice, the macro scopic and microscopic examination of the gastric contents, the chemi cal tests for the presenee of free hydrochloric acid, and organic acids (lactic, butyric ancl acetic acids), and the microscopic and cuLtural examination of bacteria. Thus it gives 116 a valuable diagnostic and therapeutic finger-post (Bauer-Deutseh, Finizio, von Hecker, A. II. Mayer, Waehenheini, et al.). The methods of obtaining these data do not differ from those in general use.