Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The invitro testing of Hemophilus influenzae and Streptococcus pyogenes for co-trimoxazole sensitivity requires certain "defined" media that have to be free of inhibitory substances. The use of Columbia agar base with Fildes extract for H. influenzae or of blood agar for S. pyogenes may produce "false-resistant" strains. The addition of thymidine phosphorylases in the form of gentlylysed horse blood (2 to 10%) does not remove all inhibitors in those tests, especially where "undefined" agar bases are used, and results in scanty growth of H. influenzae; the addition of more than 2% results in dark plates, making reading of sensitivities difficult. Fildes agar for testing H. influenzae may be made with enriched sheep or horse blood if the proper "defined" agar base is used. The use of Wellcotest or DST (Oxoid) agar is recommended with Fildes extract for H. influenzae or with blood for S. pyogenes for in vitro testing for co-trimoxazole sensitivity. The addition of thymidine phosphorylase in the form of 2% lysed horse blood does not interfere with reading. However, it results in scanty growth of H. influenzae. Proper inoculation of plates is important. The growth on the plates should be light, dense, but not confluent. Heavy growth may render some strains "false-resistant" even when defined media are used. Our results indicate that many of the previously reported resistant strains of H. influenzae and S. pyogenes may have been "false-resistant" because of the use of "undefined" media. We believe that, in view of our results, respiratory infections may be treated with co-trimoxazole until bacteriologic studies prove that this treatment is contraindicated, since H. influenzae and S. pyogenes are usually found sensitive in vitro under proper conditions.
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PMID:In vitro sensitivity of hemophilus influenzae and streptococcus pyogenes to co-trimoxazole. 109 53

The in-vitro activities of piperacillin plus tazobactam at ratios of 4:1, 8:1 and 16:1 were determined against 952 non-copy clinical aerobic bacterial isolates collected from 20 UK centres. Tazobactam enhanced the activity of piperacillin against Enterobacteriaceae, Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis. No enhancement was noted for Pseudomonas aeruginosa, other Pseudomonas spp., streptococci and enterococci. For 95.6% of strains MICs were either the same or only one two-fold dilution different with all the three ratios of tazobactam, and for most of the remaining strains the piperacillin MIC was lowest with the highest proportion of the tazobactam (4:1). The percentage of strains which remained resistant was also lowest with the 4:1 ratio. Regression analysis of MICs versus inhibition zone size with a variety of disc strengths tested on DST agar indicated that for Enterobacteriaceae, and H. influenzae 30 +4 micrograms, and 5 +1 microgram piperacillin/tazobactam discs gave the most reliable results. However, for S. aureus no disc gave good discrimination. Zone sizes obtained on DST and Iso-Sensitest agar were similar, with 96.1% of 1450 paired tests showing agreement to within 3 mm.
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PMID:The activity of piperacillin/tazobactam against clinical isolates collected in 20 UK centres and the design of a disc test for susceptibility testing. 822 17