590 SAMUEL H. HURWITZ 



metabolism of phosphoric acid is intimately connected with that of the 

 earthy metals, calcium and magnesium, on the one hand, and with the 

 excretion of nitrogenous substances, especially of uric acid, on the other. 

 A critical summary of the normal and pathological metabolism of these 

 substances has been given by Magnus-Levy (/i) and by Morawitz(fe). 



This phase of mineral metabolism in blood diseases has been re- 

 viewed by Strauss(e). In the posthemorrhagic anemias, the elimination 

 of phosphoric acid has been found variable. Jacob and Bergell in a case 

 of posthemorrhagic anemia found a retention of phosphoric acid, whereas 

 Strauss reports only a slight change following the removal of a small 

 quantity of blood. After an acute hemorrhage in dogs Gies noted a 

 variable effect on the excretion of phosphorous compounds, mainly a 

 slight decrease. This tendency to the retention of phosphorus has been 

 attributed by him to the stimulated nuclear anabolism and to the in- 

 creased nucleoprotein formation following the loss of blood. 



Chlorotic patients also show great variability in the excretion of phos- 

 phoric acid and the earthy metals. Little has been added to our knowl- 

 edge of this subject since the earlier observations of Vannini. Of the 

 five patients studied by this worker some manifested a tendency to the 

 retention and others toward the increased excretion of these substances. 

 The majority of the patients eliminated more calcium and magnesium in 

 the feces than in the urine. 



Patients with pernicious anemia have been found to show wide fluctua- 

 tions in the elimination of phosphoric acid, calcium, and magnesium dur- 

 ing different periods of the disease. Among the earlier observers some 

 report a marked loss of phosphoric acid (Schmidt, R.), others a retention 

 (von Moraczewski(rf), Strauss(e)), and still others (von Stejskal(fr)) an 

 equilibrium between the amount absorbed and the quantity excreted. Of 

 great interest is the considerable increase in the total phosphates which 

 Denis (d) reports in two patients with pernicious anemia following splenec- 

 tomy. 



As a rule, the quantity of calcium lost was found to exceed the gain 

 (Schmidt, R., von Moraczewski(d)) ; whereas, the absorption and excre- 

 tion of magnesium oxid were more frequently in equilibrium. Both 

 earthy metals, however, may be excreted in excessive amounts in other 

 types of severe anemia. Thus in a five-day metabolism experiment on a 

 patient with congenital hemolytic jaundice, McKelvy and Rosenbloom 

 noted a loss of calcium and magnesium oxids, amounting to 0.482 gram of 

 the former and 0.924 gram of the latter. This patient showed a tendency 

 to retain phosphorus. 



The great increase in the breaking down of nucleoprotein which occurs 

 in certain forms of leukemia is associated with the appearance in the urine 

 not only of increased quantities of uric acid and purin bases but also of 

 phosphoric acid. In acute leukemia, in particular, has the excretion of 



