The beta-lactamase problem: new therapeutic options

As a consequence of their successful use in prophylaxis and therapy, bacterial resistance mediated by beta-lactamases is now widely diffused among beta-lactam antibiotics. Several effective strategies have been suggested in order to overcome this problem. One interesting option is offered by the development of a series of new beta-lactam compounds that possess a very high intrinsic stability to the hydrolytic action of the most common beta-lactamases. Among these molecules the oral third generation cephalosporins represent a significant breakthrough. Cefetamet pivoxil, because of its broad coverage of most gram-negative and gram-positive community acquired pathogens, rightly belongs to these new agents. The activity of cefetamet has been confirmed in a survey in Italy involving 4191 isolates. on this collection of strains cefetamet emerged as the most active in vitro compound, followed by cefixime, with all other comparative agents (cefuroxime, cefaclor, cephalexin, cefradoxil, ampicillin, amoxicillin-clavulanate, ampicillin-sulbactam, doxycycline, erythromycin and clindamycin) displaying lower eradication rates. According to the data gathered in the Italian survey, cefetamet can be considered the only compound, among those taken into consideration, that might be selected as the drug of choice in the empiric therapy of respiratory and urinary community-acquired infections. In fact, the prevalence of resistance to cefetamet in the most prevalent pathogens occurring in this setting is, at present, sufficiently low to render therapeutic failures, based on this parameter, highly improbable.