578 SAMUEL H. HURWITZ 



4.06 grams of nitrogen, which may, according to them, be the result of a 

 possible toxogenic destruction of protein. In their patient, on the other 

 hand, Pearce and his co-workers found a slightly positive nitrogen balance. 

 In experimental hemolytic anemia produced by hemolytic serum, Pearce, 

 and Jackson noted an increased output of total nitrogen, rest nitro- 

 gen, purins, and phosphorus. These experimental results are of in- 

 terest because, as these workers point out, the changes caused by hemo- 

 lytic serum anemia, jaundice, and cell degeneration represent as close 

 an approach, aside from chronicity, to conditions in congenital hemolytic 

 jaundice as can be brought about experimentally. These studies are sug- 

 gestive and give some support to the view that a toxic destruction of tissue 

 may take place in the hemolytic anemias. 



A review of the literature of this subject indicates, therefore, that 

 even the most severe types of chronic anemia may often run their course 

 for a considerable period without injury to the body protein; but that 

 under certain conditions, a pathological increase in the .excretion of 

 nitrogen may at times occur in the course of severe anemias as a result 

 of the toxic destruction of protein. That this may explain the increased 

 protein destruction in the severe anemias of known etiology appears not 

 unlikely. Thus Rosenqvist has shown that the hemolytic lipoid extracted 

 by Tallqvist from the fish tapeworm acts destructively not only upon 

 the red blood-corpuscles, but also upon the protoplasm of other tissues, and, 

 according to Bohland a similar condition may be present in the anemia 

 of anchylostomiasis. 



That other poisons may also cause a destruction of body tissue protein 

 has gained support from the experiments of Whipple and his co-workers, 

 who demonstrated a great rise in the urinary nitrogen in animals after 

 the injection of ti toxic proteose obtained from closed intestinal loops or 

 following the absorption of protein split-products either from such loops or 

 from inflammatory exudates. 



The Nitrogen Balance in Leukemia. The nitrogenous metabolism 

 in acute and chronic leukemia has been studied by a number of investi- 

 gators. An accurate estimation of the results of many of the earlier 

 researches is rendered difficult by the shortness of the periods of observa- 

 tion, the lack of accurate determinations of the food intake, and the pres- 

 ence of such complicating factors as fever, hemorrhage, and the like. Of 

 the studies recorded in the literature, those of Magnus-Levy (c), von 

 Stejskal and Erben(a), Taylor(6), Musser and Edsall, Edsall(fc), Good- 

 all, and Murphy, Means and Aub permit of some definite conclusions. 

 These studies seem to show fairly definitely that there is, in chronic 

 leukemia, no increase in the nitrogenous metabolism at all comparable 

 with that in the respiratory metabolism. There is either a slight reten- 

 tion, a slight loss, or a nitrogen balance. 



Some differences have been found to exist in the two forms of chronic 



