THE BETA-LACTAMASE PROBLEM - NEW THERAPEUTIC OPTIONS

As a consequence of their successful use in prophylaxis and therapy, b acterial 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 i s 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 thi rd generation cephalosporins represent a significant breakthrough. Cef etamet pivoxil, because of its broad coverage of most gram-negative an d grampositive community acquired pathogens, rightly belongs to these new agents. The activity of cefetamet has been confirmed in a survey i n Italy involving 4191 isolates. On this collection of strains cefetam et 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 eradicati on rates. According to the data gathered in the Italian survey, cefeta met can be considered the only compound, among those taken into consid eration, that might be selected as the drug of choice in the empiric t herapy of respiratory and urinary community-acquired infections. In fa ct, the prevalence of resistance to cefetamet in the most prevalent pa thogens occurring in this setting is, at present, sufficiently low to render therapeutic failures, based on this parameter, highly improbabl e.