Strandberg D A, Jorgensen J H, Drutz D J
Diagn Microbiol Infect Dis. 1984 Sep;2(4):333-7. doi: 10.1016/0732-8893(84)90065-8.
The susceptibilities of singly or multiply-resistant clinical isolates of Haemophilus influenzae were determined by agar dilution to aztreonam, imipenem, and six third-generation cephalosporins. These included selected isolates that were resistant to ampicillin only, chloramphenicol only, and four isolates that were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole. All of the isolates were highly susceptible to these newer beta-lactam antibiotics. Isolates resistant to trimethoprim-sulfamethoxazole and/or chloramphenicol had susceptibilities similar to those of strains resistant only to ampicillin. Ceftriaxone, ceftizoxime, and cefotaxime were the most active of the study antibiotics (MIC90 = 0.004-0.016 micrograms/ml), and were also bactericidal at concentrations no more than twice the minimum inhibitory concentration (MIC). Minimum inhibitory concentrations of cefoperazone increased dramatically with only a 10-fold increase in inoculum size of beta-lactamase producing strains, while MICs of the other new agents were not significantly affected by elevation of the inoculum. These new antibiotics appear to be promising candidates for therapy of infections due to resistant H. influenzae.
通过琼脂稀释法测定了流感嗜血杆菌单重或多重耐药临床分离株对氨曲南、亚胺培南和六种第三代头孢菌素的敏感性。这些分离株包括仅对氨苄西林耐药、仅对氯霉素耐药的特定分离株，以及对氨苄西林、氯霉素和甲氧苄啶-磺胺甲恶唑耐药的4株分离株。所有分离株对这些新型β-内酰胺类抗生素均高度敏感。对甲氧苄啶-磺胺甲恶唑和/或氯霉素耐药的分离株，其敏感性与仅对氨苄西林耐药的菌株相似。头孢曲松、头孢唑肟和头孢噻肟是研究中活性最强的抗生素（MIC90 = 0.004 - 0.016微克/毫升），且在浓度不超过最低抑菌浓度（MIC）两倍时即具有杀菌作用。对于产β-内酰胺酶菌株，接种量仅增加10倍，头孢哌酮的最低抑菌浓度就显著升高，而其他新型药物的MICs不受接种量增加的显著影响。这些新型抗生素似乎是治疗耐药流感嗜血杆菌感染的有前景的候选药物。
