title: Effect of mixed cultures on antibiotic susceptibility testing.
abstract: Careful studies of the antibiotic susceptibilities of mixtures of bacteria likely to be encountered in clinical cultures have shown that the results obtained are completely unreliable. Mixtures of resistant and sensitive species appeared either as "resistant" or "sensitive" depending upon the organisms and the drug. A number of sensitive species gave reactions interpreted as resistant when tested in combination. Since reactions of bacterial mixtures are completely unpredictable, the authors emphasize that antibiotic susceptibility testing be limited to pure cultures.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D003352:Corynebacterium / Q000187:drug effects; D003470:Culture Media; D004917:Erythromycin / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D007612:Kanamycin / Q000494:pharmacology; D007709:Klebsiella / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D009268:Nalidixic Acid / Q000494:pharmacology; D009343:Neisseria / Q000187:drug effects; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology; D011113:Polymyxins / Q000494:pharmacology; D011511:Proteus / Q000187:drug effects; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013045:Species Specificity; D013210:Staphylococcus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D003470:Culture Media; D010406:Penicillins; D011113:Polymyxins; D009268:Nalidixic Acid; D007612:Kanamycin; D004917:Erythromycin; D002701:Chloramphenicol; D013752:Tetracycline