250 DISEASES OF THE BLOOD 



each of its constituents is decreased (Panum l ), but the propor- 

 tion of blood to body weight remains about normal. 



Anemia due to hemolytic agencies presents quite differ- 

 ent features, in that the red corpuscles are almost solely attacked 

 and the products of their disintegration are present in the plasma. 

 As a result, the plasma or serum may contain free hemoglobin, 

 and if the hemoglobin is in large amounts, it may escape into 

 the urine. Thus paroxysmal hemoglobinuria is probably due to 

 the presence in the blood of hemolytic substances, which can be 

 demonstrated in the blood of the patients during the attack. 2 

 The products of the decomposition of the hemoglobin set free 

 by hemolysis are present not only in the blood, but also in the 

 organs, particularly the liver and spleen, which become rich in 

 iron. Excretion of bile-pigments also increases, and " hematog- 

 enous jaundice " may result, the bile-pigments that are present 

 in the blood being derived from the hematoidin of the hemo- 

 globin molecule. Changes in metabolism occur which are quite 

 similar to those observed in other forms of anemia, with fatty 

 changes in all the parenchymatous organs, increased proteid 

 katabolism, and an excessive quantity of pigmentary substances, 

 particularly urobilin, in the urine. 



CHLOROSIS 



The characteristic feature of the blood in chlorosis is the 

 relatively small amount of hemoglobin in proportion to the 

 number of corpuscles. Apparently, therefore, the fault lies 

 rather in the manufacture of hemoglobin than in either a 

 destruction or a deficient formation of red corpuscles. Erben's 3 

 analyses of chlorotic blood showed that the total amount of 

 proteid is decreased, chiefly because of the deficiency of hemo- 

 globin ; the relation of serum globulins and serum albumins is 

 unchanged, while the proportion of fibrinogen is increased. 

 There is much more fatty substance than normal in both the 

 serum and the erythrocytes, but the lecithin is decreased both 

 in the serum and in the total blood, although somewhat 

 increased in the red cells. Cholesterin is decreased in both 

 serum and corpuscles. In the ash, phosphoric acid, potas- 

 sium, and iron are decreased, while calcium and magnesium are 

 both increased. An apparent increase in sodium chloride exists, 

 but it is only apparent, being the result of the increase in the 

 proportion of plasma in the blood. 



1 Virchow's Arch., 1864 (29), 241. 



2 See Donath and Landsteiner, Zeit. klin. Med., 1905 (58), 173 ; Eason, 

 Jour. Pathol. and Bact., 1906 (11), 203. 



3 Zeit. klin. Med., 1902 (47), 302. 



