Abstract
In order to explain the occurrence of a massive, brawny edema at the site of operative wounds in sensitized, reinjected dogs, the following working hypothesis was formed: Sensitized animals which have circulating ineffective amounts of the antigen, may react locally with anaphylactic changes if through any mechanism (for example, by inflammation and edema) an effective dose of the antigen accumulates in those tissues.
This conception was then tested experimentally in the rabbit.
Rabbits were sensitized by four muscular and intraperitoneal injections of 4 c.c. horse serum at 4 to 5 day intervals. 15 to 21 days after the last injection, 10 c.c. of horse serum were given intraperitoneally. 30 to 45 minutes after the reinjection, none of the rabbits having shown any collapse, the hairy surface of the ear was moistened with 1 c.c. of commercial xylol in order to produce irritation and edema.
The results were strikingly different and support the working hypothesis. In a great majority of the 36 controls edema of a fair to good degree developed in six hours; it was generally less in 24 hours, and after 48 hours had largely disappeared, leaving a practically normal ear. No dermatitis with blisters and crusts was observed; nor were hemorrhages or gangrene seen except once among the controls. In this instance the loss of substance was not more than one half millimeter of the ear tip.
In the sensitized series (17 rabbits) the edema of the ear developed more slowly and less frequently than among the controls. The maximum was reached generally in 24 hours, and the subsidence was slow, lasting 5 to 6 days. Within 22 to 48 hours, numerous small hemorrhages, blisters and subsequent crusts appeared. In these rabbits (10 out of 17) the ear after a few days showed the picture of an exfoliative dermatitis.
Get full access to this article
View all access options for this article.