GANGRENE 391 



Self-digestion of the pancreas occurs soon after death, and the pancreatic 



juice may in ^his way bring about a portmortom fat digestion that rnsornbles 

 soiHowhat tho intravital fat necrosis in its fzjross appearances/* and Wells found 

 that the same changes might ne j)ro(luced by injecting pancreatin into the bodies 

 of dead animals, or by keeping fat tissue in pancreatin solutions. WuUT found 

 that fatty acids were demonstrable by Benda's method in the pancreas of nearly 

 all cadavers. The process differs from the intra ntam form in being le.ss sharply 

 circumscribed, and microscopically by the absence of cellular and vascular reaction. 

 That the essential changes of fat necrosis can be produced postmortem is final 

 proof that they arc due to enzymes, rather than to circulatory or cellular action. 



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 stand- 

 still through the desiccation. 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 

 separation 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 contains all the innumerable 

 products of the decomposition of proteins and fats. Thus Ziegler 

 mentions as morphological elements that may be present in gangren- 

 ous tissue: Fat needles, the so-called "margarin" crystals (a mixture 

 of stearic and palmitic acids), fine acicular crystals of tyrosine, globules 

 of leucine, rhombic plates of triple phosphate, black and brown masses 

 of pigment, and crystals of hematoidin. In solution we also have, 

 beyond a doubt, all the substances formed in the decomposition of 

 proteins, from proteoses and peptones down through the different 

 amino-acids to such final products as ammonia and its salts, while CO2 

 and H2S are abundantly given off. In addition occur, undoubtedly, 

 many of the ptomains which are formed by the action of the bacteria 

 upon the amino-acids derived from the proteins.'*^ In the sputum from 

 pulmonary gangrene there is but little soluble protein, most of the 

 nitrogen, of which there is much, is in the formed elements. ^^ The 

 fetid plugs which occur in the bronchioles in gangrene, the "Dit- 

 trich's plugs," were found by Traube to be composed chiefly of fatty 



" Chiari, Zeit. f. Heilk.,'lS96 (17), 69; Pforringer, Virchow's Arch., 1899 (158), 

 126; Liepmann, ibid., 1902 (169), 532; WulfT, Berl. klin. Woch., 1902 (39), 734. 



*^ 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 enzvme dissolving elastic tissue. 



*«Orszag, Zeit. klin. Med., 1909 (67), 204. 



