Beta-lactam antibiotics (aztreonam, ampicillin, cefazolin and ceftazidime) in the control and eradication of Salmonella typhimurium in naturally resistant and susceptible mice.

This study was undertaken to investigate the efficacy of different beta-lactam antibiotics in the treatment of systemic salmonella infections in the mouse typhoid model. Innately susceptible BALB/c (Itys) and resistant CBA (Ityr) mice were used to investigate the efficacy of one monocyclic (aztreonam) and three bicyclic (ampicillin, cefazolin, ceftazidime) beta-lactam antibiotics in controlling systemic salmonella infections when given for brief or prolonged periods. The present study confirms and amplifies earlier reports on ampicillin therapy, demonstrates marked differences in the efficacy of the different antibiotics and shows that aztreonam is not only very effective but can completely eradicate the salmonellae from the RES when given early in the infection.