GANGRENE 325 



GANGRENE 



This term indicates merely that certain marked secondary 

 changes, either putrefaction or desiccation, have occurred in 

 necrotic areas of some size. Hence we have the chemical 

 changes of putrefaction added to those of necrosis in the case 

 of moist gangrene, whereas in dry gangrene nearly all the 

 chemical changes are brought to a standstill through the desic- 

 cation. In the latter it is only at the line of demarcation, where 

 some moisture remains, that chemical changes still go on ; these 

 consist chiefly of autolysis of the dead tissues, and also of their 

 digestion by leucocytes, which results eventually in the sepa- 

 ration of the dead tissue from the living ; this is best seen after 

 surface burns, carbolic-acid gangrene, etc. 



Moist gangrene is accompanied by the dual action of the 

 cellular enzymes and of the putrefactive organisms that are 

 growing in the dead tissue, and as a result such tissue con- 

 tains all the innumerable products of the decomposition of 

 proteids and fats. Thus Ziegler mentions as morphological 

 elements that may be present in gangrenous tissues : Fat- 

 needles, the so-called " margarin " crystals (a mixture of stearic 

 and palmitic acids), fine acicular crystals of tyrosin, globules of 

 leucin, rhombic plates of triple phosphate, black and brown 

 masses of pigment, and crystals of hematoidin. In the sputum 

 from pulmonary gangrene crystals of fatty acids are a peculiarly 

 characteristic feature, and according to Schwartz and Kayser, 1 

 they are produced by the action of bacteria upon fats, rather 

 than by the lipolytic enzymes of the tissues themselves. In 

 solution we also have, beyond a doubt, all the substances 

 formed in the decomposition of proteids, from proteoses and 

 peptones down through the different amino-acids to such final 

 products as ammonia and its salts, while CO 2 and H 2 S are 

 abundantly given off. In addition occur, undoubtedly, many of 

 the ptomai'ns which are formed by the action of the bacteria 

 upon the amino-acids derived from the proteids. 2 



If the necrotic tissue is in contact with living tissue over a 

 considerable area, enough of these products of autolysis and 

 putrefaction may be absorbed to cause intoxication (sapremia). 

 At the same time, the formation of such large quantities of 

 crystalloids from the proteids of the dead tissue leads to a 



1 Zeit. klin. Med., 1905 (56), 111. 



2 An interesting observation concerning gangrene of the lung has been made 

 by Eijkman (Cent. f. Bakt., Abt. 1, 1903 (35), 1), who found in this condition 

 bacteria that secrete an enzyme dissolving elastic tissue. 



