Barry A L, Fuchs P C, Jorgensen J H, Tenover F C, Allen S D, Hardy D J, McLaughlin J C
Clinical Microbiology Institute, Tualatin, Oregon 97062.
J Clin Microbiol. 1993 Mar;31(3):751-3. doi: 10.1128/jcm.31.3.751-753.1993.
In vitro studies evaluated methods for testing the susceptibility of Haemophilus influenzae to piperacillin-tazobactam combinations. Ampicillin-resistant beta-lactamase-nonproducing strains of H. influenzae may be presumed to be relatively resistant to combinations of piperacillin-tazobactam, even though they frequently appear to be susceptible by disk diffusion methods. Other ampicillin-resistant or -susceptible strains were predictably susceptible; i.e., 130 such strains gave zones of inhibition > or = 26 mm in diameter, and MICs for these strains were < or = 0.125/4.0 micrograms/ml (< or = 1.0/0.12 micrograms/ml when an 8:1 ratio was tested). A resistant category has yet to be defined. For quality control purposes, H. influenzae ATCC 49247 should give zones of inhibition 32 to 38 mm in diameter, and broth microdilution MICs should be 0.12/4.0 to 0.5/4.0 micrograms/ml.
体外研究评估了检测流感嗜血杆菌对哌拉西林 - 他唑巴坦组合敏感性的方法。对氨苄西林耐药且不产β - 内酰胺酶的流感嗜血杆菌菌株可能被认为对哌拉西林 - 他唑巴坦组合相对耐药,尽管它们通过纸片扩散法通常表现为敏感。其他对氨苄西林耐药或敏感的菌株可预测为敏感;即,130株此类菌株产生的抑菌圈直径≥26 mm,这些菌株的最低抑菌浓度(MIC)≤0.125/4.0微克/毫升(当检测8:1比例时,≤1.0/0.12微克/毫升)。尚未定义耐药类别。为进行质量控制,流感嗜血杆菌ATCC 49247应产生直径为32至38 mm的抑菌圈,肉汤微量稀释法测定的MIC应为0.12/4.0至0.5/4.0微克/毫升。