Epidemiology, Laboratory Detection, and Therapy of Penicillin-resistant Streptococcal Infections

Abstract

Streptococci cause a wide range of infections in humans including respiratory tract infections, endocarditis, meningitis, bacteremias, and skin and soft tissue lesions. Mutations in the penicillin binding proteins target sites in these organisms have recently caused resistance to penicillins and cephalosporins. The passage of resistant genetic material from one streptococcal species to another has been recognized as one of the mechanisms by which this resistance has occurred and spread. Such resistance has been a particular problem in Streptococcus pneumoniae and viridans group streptococci with penicillin resistance levels in excess of 25%, now common in both groups of organisms worldwide. Fourth-generation cephalosporins, with their enhanced antibacterial activity against Gram-positive organisms (cefpirome > cefepime) and their increased stability to the β-lactamases produced by many bacterial species, offer a new option for the treatment of potentially life-threatening infections such as pneumococcal pneumonia and meningitis with or without bacteremia. Clinical trials are currently in place to evaluate the role of these agents in these, and other, indications of Gram-positive infections. Prior studies of cefpirome therapy for infections caused by Streptococcus spp. were successful, and recent expanded in vitro investigations profess a future for expanded use of cefpirome to treat infections produced by several Gram-positive species.