[Antipneumococcal activity of erythromycin and spiramycin in 2 experimental models in mice]

Macrolides often remain the first intention treatment in many chest infections caused by S. pneumoniae. Antipneumococcal activities of spiramycin and erythromycin have then been tested in a septicaemia model and in a pulmonary infection model in mice. In the septicaemia model, spiramycin has been found 5 to 15 times more active than erythromycin by subcutaneous route and 1.5 to 6 times by oral route. In the pneumonia model, spiramycin has been found as active (one strain) to 5 times more active than erythromycin (three strains) by both subcutaneous and oral route. These data might indicate that better tissular penetration of spiramycin is responsible for better in vivo activity. These facts also support the statement that MIC should not be the only choice standard of infectious chemotherapy.