ing
amounts of salt.

Dr. O'Hara likewise describes another test known as ~The Added Urea
and Salt Test~, which was first described by von Monakow and also
carried out in the Peter Bent Brigham Hospital. The method used was as
follows:

ADDED UREA AND SALT TEST

Patient is given 75 grams of protein, 4 grams of sodium chloride, and
1500 c.c. of water, with a caloric value of from 2000 to 2200
calories. After the output of fluid, salt and nitrogen reaches an
equilibrium on this diet on one day 10 grams of additional salt is
given and several days later the patient receives 20 grams of urea.
This order may be reversed. The daily output of urine, salt, and
nitrogen is determined and charted. After the salt and nitrogen is
added to the diet in normal individuals, their excretion after
forty-eight hours returns to its previous level. In diseased kidneys
this may not be the case.

~Value of Tests.~--Thus it is seen that in these tests for kidney
functions, an effort is made to determine the extent of damage wrought
by the disease upon the renal organs and the manner in which they
react under definite circumstances. However, it is not so simple as it
would seem to formulate a dietary based on the findings resulting from
the renal tests. Notwithstanding this, these tests are coming more and
more into use, both in hospitals and private practice, and a nurse
must understand just how they are carried out, and must realize that
unless her part is performed with absolute accuracy the entire value
of the test will be obliterated. Too much stress cannot be laid upon
this phase of the test, if it is to be of any value whatsoever in
determining the condition of a diseased kidney.

CHRONIC INTERSTITIAL NEPHRITIS

This form of nephritis is more insidious in character, developing more
slowly and manifesting different characteristics, than those seen in
some of the other types already mentioned. The condition is, as a
rule, associated with heart symptoms and high blood pressure. The
blood shows an increase in urea and other end-products of protein
metabolism, whereas there is no manifest change in the metabolism of
salt or water. The great increase in volume of urine voided would show
an inability on the part of the kidneys to eliminate a highly
concentrated urine. This hypothesis is further demonstrated in the
urine tests.

~Urinalysis.~--Upon analysis the urine in these cases shows less
albumen and fewer casts than found in