Appelbaum P C, Spangler S K, Jacobs M R
Department of Pathology (Clinical Microbiology), Hershey Medical Center, Hershey, PA 17033.
J Antimicrob Chemother. 1993 Aug;32(2):223-31. doi: 10.1093/jac/32.2.223.
Susceptibilities of 539 Gram-positive and Gram-negative anaerobes were tested by agar dilution against 15 new and existing antimicrobial agents. Organisms included 218 Bacteroides fragilis group strains, 15 non-fragilis group Bacteroides, 130 Porphyromonas/Prevotella, 49 fusobacteria, 50 peptostreptococci, 53 clostridia and 24 Gram-positive non-sporeforming bacilli. Of 412 Gram-negative bacilli, 89% were beta-lactamase-positive, while only two of the Gram-positive strains (both clostridia) produced this enzyme. Using established and preliminary breakpoints, all strains were susceptible to biapenem and imipenem (MIC90s 1 mg/L) and chloramphenicol (MIC90 8 mg/L). Only one of all the strains tested (a Cl. innocuum) was resistant (MIC > 4 mg/L) to RP59500; the latter had MIC90 2 mg/L, while 98% of strains were susceptible to trospectomycin (MIC90 16 mg/L). Ninety-nine per cent of strains were susceptible to piperacillin/tazobactam (MIC90 8 mg/L) compared to 86% to piperacillin (MIC90 > 64 mg/L). Corresponding data for ticarcillin/clavulanate versus ticarcillin were 97% susceptible (MIC90 8 mg/L) compared to 83% (MIC90 > 64 mg/L). Enhancement of the beta-lactam by the inhibitors was only seen in beta-lactamase-producing strains. Amoxycillin and cefoperazone were less often active (36% susceptible, MIC90 > 256 mg/L and 66% susceptible, MIC90 64 mg/L, respectively). Cefoxitin had greater activity than cefotetan (90% susceptible, MIC90 32 mg/L, compared to 72% susceptible, MIC90 > 64 mg/L). Metronidazole was active against 94% of strains (MIC90 4 mg/L). All metronidazole-resistant strains were Gram-positive (75% of non-sporeforming bacilli, 9% of clostridia and 6% of peptostreptococci). Ninety per cent of strains were susceptible to clindamycin (MIC90 4 mg/L).
采用琼脂稀释法对539株革兰氏阳性和革兰氏阴性厌氧菌进行了15种新的和现有的抗菌药物的药敏试验。受试菌株包括218株脆弱拟杆菌群菌株、15株非脆弱拟杆菌群拟杆菌、130株卟啉单胞菌/普雷沃菌、49株梭杆菌、50株消化链球菌、53株梭菌和24株革兰氏阳性无芽孢杆菌。在412株革兰氏阴性杆菌中，89%产β-内酰胺酶，而革兰氏阳性菌株中只有2株（均为梭菌）产生该酶。根据既定的和初步的折点，所有菌株对比阿培南、亚胺培南（MIC90均为1mg/L）和氯霉素（MIC90为8mg/L）敏感。所有受试菌株中只有1株（无害梭菌）对RP59500耐药（MIC>4mg/L）；后者的MIC90为2mg/L，而98%的菌株对曲氟沙星敏感（MIC90为16mg/L）。99%的菌株对哌拉西林/他唑巴坦敏感（MIC90为8mg/L），而对哌拉西林敏感的菌株为86%（MIC90>64mg/L）。替卡西林/克拉维酸与替卡西林的相应数据分别为97%敏感（MIC90为8mg/L）和83%（MIC90>64mg/L）。β-内酰胺酶抑制剂增强β-内酰胺类药物的作用仅见于产β-内酰胺酶菌株。阿莫西林和头孢哌酮的活性较低（分别为36%敏感，MIC90>256mg/L和66%敏感，MIC90为64mg/L）。头孢西丁的活性高于头孢替坦（90%敏感，MIC90为32mg/L，而72%敏感，MIC90>64mg/L）。甲硝唑对94%的菌株有活性（MIC90为4mg/L）。所有耐甲硝唑菌株均为革兰氏阳性菌（75%的无芽孢杆菌、9%的梭菌和6%的消化链球菌）。90%的菌株对克林霉素敏感（MIC90为4mg/L）。
