The Combined Effect of Sulfanilamide and Penicillin in Treatment of Experimental Erysipelothrix Rhusiopathiae Infection of Mice

Abstract

In a previous communication (1) we reported the results of determinations oi the therapeutic effect of sulfonamide compounds in mice inoculated with Erysipelothrix rhusiopathiae. A report was also made of the ineffective use of these compounds in treatment of patients with erysipeloid of Rosenbach and in treatment of one patient with the septicemic form of the infection (2). In our experimental study sulfanilamide, sulfapyridine, sulfathiazole and sulfadiazine were separately administered to mice orally in doses of 0.2 Gm. per kilogram of body weight. To some the compounds were administered twice daily for two days before inoculation with a virulent strain of Erysipelothrix rhusiopathiae and twice daily thereafter for six additional days. For others treatment was begun four hours after inoculation and then administered twice daily for six additional days; in still others, for eight additional days. It was observed that 12.5 per cent of mice treated before or after the administration of these compounds survived. Additional evidence of some therapeutic effect was the greater percentage (50 per cent) of survival of the animals treated before inoculation and the longer time of survival of animals treated after inoculation compared with those of the untreated control group. The therapeutic effect of these compounds is therefore limited. Sulfanilamide and sulfapyridine appeared to give better results than sulfathiazole and sulfadiazine. The therapeutic effect of these compounds was slightly enhanced when they were employed in conjunction with subcurative injections of immune serum. In another communication (3) we studied the therapeutic effects of penicillin and streptomycin in mice inoculated with Erysipelothrix rhusiopathiae. In this study (3) the sodium salt of penicillin was administered in 5 daily injections for five successive days. The last of the daily injections (given in peanut oil-beeswax was twice the amount of the preceding four. The number of units per injection varied from 20 to 300. In some mice treatment was initiated immediately after inoculation, for others eight hours after inoculation, for still others sixteen hours after inoculation. The survival rate was 100 per cent with 600 units daily administered immediately after inoculation, and after treatment with 1,800 units daily beginning 8 hours after inoculation. The survival rate was 50 per cent after treatment with either 600 or 1200 units daily administered in 8 hours after inoculation. Streptomycin showed very slight therapeutic effect. Only four mice survived of 48 treated with varying numbers of units up to 3,600 units daily. The purpose of the present investigation was to determine if combined sul-