Facultative anaerobes are the most common cause of infections in anoxic parts of the human body, including deep wound, vagina, periodontal pockets, gastrointestinal tract, genitourinary tract and lungs. Generally, antibiotic susceptibility tests (AST) for facultative anaerobes are performed under aerobic conditions due to ease of handling and rapid growth. However, variation in susceptibility of facultative anaerobes to antibiotics under aerobic and anaerobic conditions can lead to failure of antibiotic treatment. Our study evaluated the susceptibility of facultative anaerobic microorganisms to antibiotics during growth under anaerobic or aerobic conditions. We compared the resistance patterns of representatives from 15 bacterial genera isolated from the human-gastrointestinal tract against 22 different antibiotics from six classes under aerobic and anaerobic conditions. Preliminary results obtained by a disc diffusion method were verified using minimum inhibitory concentration (MIC) testing. The results demonstrated that 7-strains had a similar pattern of drug resistance under both conditions, while the remaining ten strains had significant differences in resistance patterns between aerobic and anaerobic conditions for at least one antibiotic. We conclude that successful antibiotic therapy for host-associated pathogens requires proper assessment of the oxygen condition of the growth environment and MIC testing of each pathogen under anaerobic and aerobic conditions.

兼性厌氧菌是人体缺氧部位感染的最常见原因，包括深部伤口、阴道、牙周袋、胃肠道、泌尿生殖道和肺部。通常，由于易于处理和快速生长，兼性厌氧菌的抗生素敏感性试验 (AST) 在有氧条件下进行。然而，兼性厌氧菌在好氧和厌氧条件下对抗生素敏感性的变化会导致抗生素治疗失败。我们的研究评估了兼性厌氧微生物在厌氧或好氧条件下生长过程中对抗生素的敏感性。我们比较了在好氧和厌氧条件下，从人类胃肠道中分离出的 15 个细菌属代表对来自六类的 22 种不同抗生素的耐药性模式。使用最小抑制浓度 (MIC) 测试验证了通过圆盘扩散法获得的初步结果。结果表明，7 株菌株在两种条件下具有相似的耐药模式，而其余 10 株菌株在需氧和厌氧条件下对至少一种抗生素的耐药模式存在显着差异。我们得出结论，对宿主相关病原体的成功抗生素治疗需要对生长环境的氧气条件进行适当评估，并对厌氧和需氧条件下的每种病原体进行 MIC 测试。使用最小抑制浓度 (MIC) 测试验证了通过圆盘扩散法获得的初步结果。结果表明，7 株菌株在两种条件下具有相似的耐药模式，而其余 10 株菌株在需氧和厌氧条件下对至少一种抗生素的耐药模式存在显着差异。我们得出结论，对宿主相关病原体的成功抗生素治疗需要对生长环境的氧气条件进行适当评估，并对厌氧和需氧条件下的每种病原体进行 MIC 测试。使用最小抑制浓度 (MIC) 测试验证了通过圆盘扩散法获得的初步结果。结果表明，7 株菌株在两种条件下具有相似的耐药模式，而其余 10 株菌株在需氧和厌氧条件下对至少一种抗生素的耐药模式存在显着差异。我们得出结论，对宿主相关病原体的成功抗生素治疗需要对生长环境的氧气条件进行适当评估，并对厌氧和需氧条件下的每种病原体进行 MIC 测试。而其余十种菌株在需氧和厌氧条件下对至少一种抗生素的耐药模式存在显着差异。我们得出结论，对宿主相关病原体的成功抗生素治疗需要对生长环境的氧气条件进行适当评估，并对厌氧和需氧条件下的每种病原体进行 MIC 测试。而其余十种菌株在需氧和厌氧条件下对至少一种抗生素的耐药模式存在显着差异。我们得出结论，对宿主相关病原体的成功抗生素治疗需要对生长环境的氧气条件进行适当评估，并对厌氧和需氧条件下的每种病原体进行 MIC 测试。