Tally F P, Sullivan C E
Pharmacotherapy. 1981 Jul-Aug;1(1):28-38. doi: 10.1002/j.1875-9114.1981.tb03551.x.
Metronidazole is a 5-nitroimidazole that has selective activity against anaerobic microorganisms, including bacteria and protozoa. Intravenous metronidazole has recently been approved by the U.S. Food and Drug Administration for the treatment of serious anaerobic bacterial infections. It is usually bactericidal at low concentrations, and its spectrum of activity encompasses almost all anaerobic bacteria and some capnophilic organisms. Anaerobic bacteria known to be resistant to metronidazole include occasional anaerobic cocci, some nonsporulating gram-positive bacilli and propionibacterium. Metronidazole is the most active antimicrobial agent against Bacteroides fragilis, the most resistant of anaerobic bacteria. Kill-curve studies demonstrate that there is a 2 to 5 log decrease in the number of colony forming units of B. fragilis and Clostridium perfringens within one hour. The only well documented metronidazole-resistant strain is a B. fragilis isolated from the normal flora of a patient on long-term metronidazole therapy for Crohn's Disease. Metronidazole resistance in Trichomonas vaginalis has recently been described in a few strains that are able to survive at increased oxygen tensions. Metronidazole has been shown to be efficacious in certain protozoal infections including trichomonal vaginitis, extraintestinal amebiasis, and giardiasis. Clinical studies have shown metronidazole to be efficacious in the therapy of a variety of anaerobic infections, including non-traumatic brain abscesses, intraabdominal sepsis, pelvic suppuration and necrotizing soft tissue infections. There have been disappointing results in the therapy of anaerobic pleuropulmonary infections with a number of superinfections caused by aerobic bacteria. Since metronidazole lacks any activity against aerobic bacteria, it must be combined with other agents, usually aminoglycosides, in the treatment of mixed infections involving anaerobic and aerobic bacteria.
甲硝唑是一种5-硝基咪唑类药物，对包括细菌和原生动物在内的厌氧微生物具有选择性活性。静脉注射甲硝唑最近已被美国食品药品监督管理局批准用于治疗严重的厌氧细菌感染。它在低浓度时通常具有杀菌作用，其活性谱几乎涵盖所有厌氧细菌和一些嗜二氧化碳菌。已知对甲硝唑耐药的厌氧细菌包括偶尔出现的厌氧球菌、一些非芽孢形成革兰氏阳性杆菌和丙酸杆菌。甲硝唑是对脆弱拟杆菌最具活性的抗菌剂，脆弱拟杆菌是最耐药的厌氧细菌。杀菌曲线研究表明，在一小时内脆弱拟杆菌和产气荚膜梭菌的菌落形成单位数量减少2至5个对数。唯一有充分记录的甲硝唑耐药菌株是从一名因克罗恩病接受长期甲硝唑治疗的患者正常菌群中分离出的脆弱拟杆菌。最近在一些能够在较高氧张力下存活的阴道毛滴虫菌株中发现了甲硝唑耐药性。甲硝唑已被证明对某些原生动物感染有效，包括滴虫性阴道炎、肠外阿米巴病和贾第虫病。临床研究表明，甲硝唑在治疗多种厌氧感染方面有效，包括非创伤性脑脓肿、腹腔内脓毒症、盆腔化脓和坏死性软组织感染。在治疗厌氧性胸膜肺部感染以及由需氧菌引起的一些二重感染方面，结果令人失望。由于甲硝唑对需氧菌没有任何活性，在治疗涉及厌氧菌和需氧菌的混合感染时，它必须与其他药物联合使用，通常是氨基糖苷类药物。
