title: Evaluation of the Bacti-Lab streptococci culture systems for selective recovery and identification of group A streptococci.
abstract: Twenty-nine lots of Bacti-Lab streptococci culture plates containing nalidixic acid, neomycin, and amphotericin B were inoculated with 25 strains of group A, B, C, F, and G strepotocci, 13 strains of nonstrepotcoccal organisms representative of the throat flora, and 198 fresh clinical thorat specimens to determine the accuracy of the plates in identifying group A streptococci. With the Bacti-Lab test plates 98.87% of the beta-hemolytic streptococcal strains tested produced growth 95.51% yielding more than 50 colonies. Of the nonstreptococcal beta-hemolytic and non-beta-hemolytic organism tested, 79.54% were inhibited by the selective media. When bacitracin disks were used for presumptive identification group A streptococci from clinical thorat specimens, 12.00% false positive and 0.00% false negative results were obtained as measured by the direct flourescent-antibody and Lancefield grouping methods.
mesh_terms: D000362:Agar; D000666:Amphotericin B; D000818:Animals; D001414:Bacitracin; D001431:Bacteriological Techniques / Q000295:instrumentation; D001769:Blood; D005069:Evaluation Studies as Topic; D005189:False Positive Reactions; D006801:Humans; D009268:Nalidixic Acid; D009355:Neomycin; D010614:Pharynx / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000254:growth & development; D012756:Sheep; D013211:Staphylococcus aureus / Q000254:growth & development; D013291:Streptococcus / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification*
chemical_list: D001414:Bacitracin; D009268:Nalidixic Acid; D000666:Amphotericin B; D000362:Agar; D009355:Neomycin