300 EDEMA 



free (Christen 1 ). Cholesterin is present particularly in fluids 

 that have been standing for a long time in the body, appearing 

 often as visible crystals shining in the fluid ; it probably origi- 

 nates from degenerating cells. Glycogen is not present (Car- 

 riere 2 ). The various immune bodies, cytotoxins, hemolysins, 

 bacteriolysins, agglutinins, etc., seem to pass freely into both 

 transudates and exudates, and their presence is not characteristic 

 of either. 3 



Toxicity. Contrary to earlier ideas, transudates are not 

 toxic, even in nephritis (Bay lac, 4 Boy-Teissier, 5 Lafforcade 6 ), 

 and therefore the toxic manifestations frequently observed after 

 reduction of edema in nephritis, and ascribed to absorption of 

 poisons in the transudates, are probably due to some other cause. 

 In inflammatory exudates, of course, the causative agents as 

 well as the products of cell destruction render the fluids poisonous. 



Enzymes. All the enzymes of the plasma may appear 

 in edematous fluids, being in all cases probably more abundant 

 in exudates than in transudates. According to Carriere, 7 

 oxidases are inconstant, even in exudates. Lipase is said to be 

 much more abundant in exudates than in transudates. 8 (Con- 

 cerning proteolytic enzymes see "Autolysis of Exudates," 

 Chap, iii.) 



Precipitin Reactions, etc. Edematous fluids have been 

 often used as a source of material in immunizing animals against 

 human proteids. The precipitins thus formed are specific for 

 human serum or for the proteids of the effusion, but cannot be 

 used to differentiate a transudate from an exudate, or a hydro- 

 thorax fluid from an ascites fluid (Quadrone 9 ). Immune bodies, 

 complement, agglutinins, and antitoxins are present in effusions 10 ; 

 e. g.j the common use of blister fluid for the Widal test. Fur- 

 thermore, according to Hamburger, 11 edema fluid is distinctly 

 more bactericidal than normal lymph. 



1 Cent. f. inn, Med., 1905 (26), 329. 



2 Compt. Kend. Soc. Biol., 1899 (51), 467. 



3 Granstrom, Inaug. Dissert., St. Petersburg, 1905. 



4 Compt. Kend. Soc. Biol., 1901 (53), 519. 



5 Ibid., 1904 (56), 1119. 



6 Gaz. heb. Med. et Chir., Jan. 28, 1900. 



7 Compt. Kend. Soc. Biol., 1899 (51), 561. 



8 Zeri, II Policlinico, 1903 (10), No. 11 ; Memmi, Clin. Med. ItaL, 1905, 

 No. 3. 



9 Cent. f. Bakt. (ref.), 1905 (36), 270. 



10 Granstrom, loc. cit. 



11 Virchow's Arch., 1899 (156), 329. 



