Leading article Inhibitor-resistant -lactamases

Of the various strategies developed to cope with the problems of -lactamase-producing bacteria, the use of specific -lactamase inhibitors has been most widely applied to treat various infectious diseases over the last ten years. Clavulanic acid, sulbactam and tazobactam, the three such molecules available for therapy, function as suicide inhibitors producing irreversible inhibition of Ambler class A -lactamases. 1‐3 In combination with lactam molecules, such as ampicillin for sulbactam, amoxycillin and ticarcillin for clavulanate, and piperacillin for tazobactam, these inhibitors provide broad-spectrum antimicrobial activity. Nevertheless, as early as 1987, amoxycillin-resistant isolates of Escherichia coli which were less susceptible to co-amoxiclav were noted. 4 Since then, such isolates have been occurring more frequently, especially among those organisms responsible for urinary tract infections. 5,6