250 MALIGNANT EDEMA 
MALIGNANT EDEMA 
Synonyms. Septiceemia gangreenosa; oedema malin; traumatic 
spreading gangrene. 
Characterization. Malignant edema is an acute, wound infection 
disease of domesticated animals, which is especially characterized 
by edematous, later crepitating tumors at the place of infection due 
to Bacillus oedematis maligni. Nearly all species of animals including 
man are susceptible. 
History. Crepitating tumors following wounds, withdrawing of 
setons, castration, and the like have long been known. It was 
pointed out by Girard that crepitating tumors in sheep could be caused 
by subcutaneous injection of animal tissue taken from putrefying 
tissue. Chauveau (1873) showed by experiments performed on goats 
that the development of the disease stood in a close relation to living 
organisms present in injected putrescent blood. Pasteur, in 1887, 
studied more closely the organism and named it Vibrion septique. He 
obtained it in pure culture. Later Koch and Gaffky (1881) studied 
exhaustively the disease caused through contamination by contact 
with the ground, which they named malignant edema. Since then 
Kitt, Jensen, Sand and Leclainche have studied its bacteriology, while 
Jensen and Sand, v. Ratz, Froéhner, Carl and others have made 
valuable contributions to the appearance of the malady among 
domesticated animals. Malignant edema is a wide spread but not a 
common disease. 
Etiology. Malignant edema is caused by Bacillus oedematis 
maligni Koch (Vibrion septique Pasteur). This was the first anaero- 
bic organism to be isolated or studied. It is found in the soil and also 
in the intestinal tract of certain animals. It is described as a bacillus 
resembling that of anthrax, but somewhat more slender with rounded 
ends, and spore bearing. It is a strict anaerobe. In artificial cul- 
tures as well as in the animal body, after the death of the latter the 
bacilli grow into Jong filaments. Exceptionally, living animals con- 
tain the spore bearing bacilli in the edematous fluid (Jensen and 
Sand). The bacilli stain very readily with aqueous aniline dyes. In 
culture media containing sugar, gases are formed which have a charac- 
teristic disagreeable odor. The inoculation of a pure culture into thé 
deep connective tissue of mammals and birds produces a tumor 
quickly spreading from the place of inoculation and later crepitating 
on account of the formation of gas. Several varieties of its bacillus 
