Epidemiology of beta-lactamases in Africa: correlation with resistance to beta-lactam antibiotics.

In 45 centers from eight African countries, 2,888 bacterial isolates were collected from patients with community-acquired infections. Isolated pathogens included Staphylococcus aureus (29%), Escherichia coli (20%), Neisseria gonorrhoeae (6%), Proteus species (6%), Klebsiella species (6%), Klebsiella pneumoniae (4%), and Staphylococcus epidermidis (4%). An overall sensitivity of 16.2% was shown to penicillin G (number of isolates tested = 2,467), 31.8% to ampicillin (2,687), 45% to amoxicillin (1,959), and 84.9% to cefuroxime (2,888). Beta-lactamase presence was measured by a chromogenic method. Beta-lactamase was found in 75% of all pathogens tested, including 69.5% of gram-negative and 83.3% of gram-positive pathogens; 73% of E coli isolates, 76% of N gonorrhoeae, 75% of Klebsiella species, and 84% of S aureus were beta-lactamase positive. Beta-lactamase presence was associated with bacterial resistance for penicillin G, ampicillin, and amoxicillin, but not cefuroxime, whose sensitivity remained high. The higher resistance rates and beta-lactamase prevalence in Africa suggest the need for national antibiotic prescribing policies and surveillance schemes and replacement of relatively ineffective penicillins with newer agents such as cefuroxime.