[A comparison of Ultrax, Diazil, Bactrim and Spiramycin in experimental toxoplasmosis in mice (author's transl)].

White mice infected intraperitoneally with the RH-strain of Toxoplasma gondii (inoculum size 50,000 to 100,000 free protozoans per mouse) received treatment between the second and eighth day after infection with sulphamethazine-pyrimethamine, sulphamethoxy-diazine-pyrimethamine, trimethoprim-sulphamethoxazole or spiramycin subcutaneously. All untreated controls and all mice of the trimethoprim-sulphamethoxazole and spiramycin-treated groups died during the acute stage (except two mice in the latter group on the 15th day). The mean survival times were 6.5, 7.5 and 7.6 days, respectively. The best results were obtained in the sulphamethazine-pyrimethamine-treated mice; 18 out of 27 survived the 30-day observation period (5 cured), in contrast to only 9 out of 40 sulphamethoxydiazine-pyrimethamine-treated mice. Considering the high pathogenicity of the RH-strain, the differences in immunological defence mechanisms in mice (absence of antibody-activating "accessory factor") and the late commencement of treatment of the infected mice, one can state that the combination of sulphamethoxydiazine-pyrimethamine should also be capable of overcoming acute human toxoplasmosis in pregnancy. Spiramycin, by contrast, should be given only in cases where sulphonamide intolerance exists and must then be given in high doses until delivery. The combination of sulphamethoxazole-trimethoprim cannot be recommended.