HEMOLYSIS HY JiACTKRIA 210 



Agglutination of the corpuscles during life may bo of great patho- 

 logical importance, for such masses of agglutinated corpuscles may 

 readily produce capillary thrombi and emboli, which, if wide-spread, 

 may create much disturbance. Somethmes the serum of one indi- 

 vidual of a species agglutinates the corpuscles of another individual 

 of the same species (isoagglutination) j^^" a fact which must be taken 

 into account in performing transfusion of blood, lest dangerous ag- 

 glutination take place. Agglutination of an individual's corpuscles 

 by his own serum {autoagglutination) , may also be observed under 

 experimental, and perhaps under pathological conditions (Land- 

 steiner),**^ this pathological autoagglutination probably occurring 

 especially at temperatures below 37°. (See Paroxysmal Hemoglobin- 

 uria.) Many bacteria produce substances that are agglutinative for 

 human red corpuscles, among them being B. typhosus, pyocyaneus, 

 and staphylococcus. Flexner^^ has found in typhoid fever thrombi 

 that seemed to be composed of agglutinated red corpuscles, almost 

 free from fibrin and leucocytes. Probably many of the so-called 

 "hyaline thrombi" found frequently in infectious diseases are really 

 composed of agglutinated, partly hemolyzed red corpuscles (see 

 "Thrombosis," Chap. xiii). 



Hemolysis by Bacteria^^ 



Both pathogenic and non-pathogenic bacteria produce hemolytic 

 substances that are excreted into the fluids in which they grow. Dur- 

 ing many infectious diseases marked hemolysis occurs, especially in 

 those diseases accompanied by septicemia. After death the hemo- 

 globin of the blood goes into solution, and the resulting staining of 

 the walls of the blood-vessels, and later of the tissues everywhere, is 

 generally familiar. In the post-mortem hemolysis probably the pu- 

 trefactive organisms are chiefly concerned, although it is marked a 

 very short time after death in many cases of septicemia, particularly 

 when the infecting organism is the streptococcus, and here probably 

 the pathogenic organism is the chief cause of the hemolysis. The 

 hemolytic action of bacteria can be studied both in vitro and in vivo. 

 Among the best known hemolytic bacterial toxins are tetanolysin, 

 pyocyanolysin, typholysin, staphylolysin,^'' and streptocolysin, as they 

 have been termed. Of tliese, the case of pyocyanolysin is question- 



"« Review bv Happ, Jour. Exp. Med., 1920 (31) 313. 



s^ See also Clough and Richter, Bull. Johns Hop. Hosp., 1918 (29), 86; Rous 

 and Robertson, Jour. Exp. Med., 1917 (27), 509. 



" Univ. of Penn. Med. Bull., 1902 (15), 324; Amer. Jour. Med. Sci., 1903 (126), 

 202. 



*^ See Pribram, Kolle and Wassermann's Handbuch., 1913 (II), 1328. 



*" Analysis of staphj-loh^sin by Burkhardt (Arch. exp. Path, und Pharm., 1910 

 (63), 107), showed it to be dialyzable, protein- and biuret-free, thermolabile and 

 soluble in ether. From B. puiidum he isolated a hemolj'tic substance which 

 seems to be a derivative bj' oxidation of erucacic acid (oxj-diniethylthiolerucacic 

 acid). 



