NOTES ON 
EXAMINATION OF URINE. 
Prepared by JUDSON DALAND, M.D., 
Instructor in Clinical Medicine, University of Pennsylvania. 
ASED UPON PROF. JAMES TYSON’S “ HANDBOOK FOR PRACTICAL EXAMINATION 
OF URINE.” SIXTH EDITION. 
In the examination of urine, the following are the steps found most con- 
renient in actual practice. Observe:— /1 jA 
I. The quantity passed in twenty-four hours. 
II. Color and transparency. 
iii. odor. ' ;A r) Js - f 
IV. Reaction. . \ O 
V. Specific gravity. \ -p\ J / 
VI. 1 resence or absence of sediment, its quantity apd character / \ 
VII. Presence or absence of albumin. . -Vv f y 
VIII. Presence or absence of sugar. 
Heat and Acid Test. 
The best test for determining the presence of albumin in urine is heat 
corroborated by nitric acid. To apply this test, fill a test-tube one-fourth its 
depth with perfectly clear urine, to which, if it be not distinctly acid in reac- 
tion, a drop or two of acetic acid is added—only enough to make it clearly 
acid—and the fluid boiled over a spirit lamp. If an opacity results, the 
slightest degree of which becomes visible in a clear urine held in a good light, 
it is due oiiher to albumin or earthy phosphates. If the latter, it promptly 
disappears on the addition of a few drops of nitric acid; if albumin, it is 
permanent. 
Acetic acid is preferred to nitric for acidulating the urine, because not 
only is it true that a small quantity of albumin is dissolved by a large 
amount of nitric acid, but also that if a drop or two of nitric acid be added 
to a specimen of albuminous urine, so as to render it distinctly acid, it may 
happen, on boiling, that no precipitate will appear, although much albumin 
is present. This is because the serum-albumin is converted into acid-albumin 
or syntonin, which is not coagulated by heat. 
The Nitric Acid Test. 
This is best applied according to Heller’s method. Upon a convenient 
quantity of pure, colorless nitric acid in a small test-tube, allow to trickle 
from a pipette, down the side of the inclined glass, an equal amount of clear 
urine, which will thus overlie the acid. If albumin is present, there 
appears at the point of contact between the urine and nitric acid a sharp 
white band or zone, of varying thickness, according to the quantity of 
albumin present. 
Occasionally, a somewhat similar white zone is formed by the action of 
nitric acid on the mixed urates if present in excess, by which the more 
insoluble acid urates are thrown down. This zone might be mistaken for 
that of albumin, but the acid urates begin to appear, not so much at the 
border, between the urine and acid, as higher up; nor does the zone on its 
upper surface remain so sharply defined, but, while under examination, is 
seen to diffuse itself into the urine above. Further, the application of heat 
causes its immediate disappearance. 
Rarely the urine is so concentrated that nitric acid forms crystals of 
nitrate of urea, which, however, are dissolved by the application of heat. 27 
The Picric Acid Test. 
Into a test-tube, about six inches long, pour a four-inch column of clear, 
transparent urine; then, holding the tube in a slanting position, pour gently 
an inch of a saturated solution of picric acid on the surface of the urine, 
where, in consequence of its low specific gravity (1005), it mixes only with 
the upper layer of the urine. 
As far as the yellow color of the picric acid solution extends, the coagu- 
lated albumin renders the liquid turbid, contrasting with the transparent 
urine below. For the action of the test,'there must be an actual mixture, and 
not a mere surface contact. When, in consequence of the scantiness of the 
albumin, the turbidity is very slight, the application of heat to the upper 
part of the turbid column increases it. Then, if the tube bo placed in a 
stand, the coagulated albumin will gradually subside, and, in the course of 
an hour or so, forms a delicate, horizontal film at the junction of the colored 
and unstained stratum of urine. No previous acidulation of the urine is 
required, as the picric acid accomplishes this, if needed. Urates, peptones 
and vegetable alkaloids, like quinine, morphine, etc., are precipitated by 
picric acid from urine containing them, but it should be remembered that 
the application of a moderate amount of heat will dissolve the ring thus 
formed. * 
By Fehling’s Solution. 
Place a small quantity of Fehling’s solution in a test-tube, and dilute it 
with about four times its bulk of distilled water, and then boil the mixture 
for a few seconds. If a precipitate occur, the test solution is worthless, and 
a fresh supply obtained. To the boiling, diluted, fresh Feliling's solution 
add the suspected urine, drop by drop, and if sugar is present, a yellowish or 
reddish-yellow precipitate, the suboxide of copper, appears. Whenever 
Fehling’s solution shows the presence of sugar in the urine, this result 
should be corroborated by the application of the subnitrate of bismuth, or 
BOtger’s test, as follows:— 
SUBNITRATK OF BlSMUTII TEST. 
Add to urine an equal quantity of liquor potassa? or soda? and a pinch of 
ordinary subnitrate of bismuth, and boil; when, if sugar is present, the sub- 
nitrate is converted into the black metallic bismuth. If tiie quantity of 
sugar is small, the bismuth assumes a grayish hue. 
Before applying either of the above tests, albumin, if present, should 
always be removed by the addition of acetic acid, boiling and filtration. 
It should be remembered that occasionally uric acid, creatinin, etc., have 
the power of reducing Fehling’s solution, and thus leading us to erroneously 
believe sugar to ho present. 
The Picric Acid and Potash Test. 
To a fluid-drachm of suspected urine, add 40 minims of a saturated solu- 
tion of picric acid and half a drachm of liquor of potassse. Boil this mixture, 
and, if sugar is present, a dark, mahogany-red color will be produced. 
For quantitative work, perhaps the fermentation test can be most easily 
applied by the physician. 
Quantitative Determination of Sugar by the Fermentation Test. 
Having taken the specific gravity of the urine, add a piece of compressed 
yeast about the size of a walnut, then place it in a warm place, about 80-‘J0° 
F , for three or four hours, or until Fehling’s solution shows no sugar. 
Allow the urine to cool to the original temperature, and again take the 
specific gravity. Multiply the number of degrees of specific gravity lost by 
.23, and the result is the percentage amount of sugar present