Studies on the Chemistry of Blood Serum

In a recent publication 1 the author recorded the results of a chemical analysis of blood sera from different diseased conditions. It was observed that the proteins of the serum are subject to extensive variations, and in certain diseases the globulin fraction in the serum is greatly increased. In the serum of cases of chronic parenchymatous nephritis the increase in the globulin content is most pronounced, and the globulin may constitute nearly all of the protein present. On the other hand, the protein fractions of sera from cases of chronic interstitial nephritis present, in their quantitative relations, little or no change from the normal. In certain cases of the latter group, there appears to be a tendency for the globulin in the serum to fall below the normal percentage. For reasons which will be given in a future publication the author is of the opinion that the changes occurring in the protein composition of blood serum in different diseases are not accidental, but are the results of well defined influences acting upon the blood and its serum. In contrasting the findings in the sera of patients with chronic interstitial nephritis and with chronic parenchymatous nephritis, the conclusion is reached that the two diseases are genetically different in respect to the blood, and that the change in the protein composition of the blood serum plays a direct part in the production of some of the clinical manifestations of the two types of renal disease. The composition of the urine and the blood serum (the chlorides and nitrogenous waste products) in chronic interstitial nephritis depends upon the degree of impairment of the renal function; whereas in the chronic parenchymatous nephritis the chemistry