Rationale: The medical history and findings on physicalexamination should arouse suspicion of anaerobic infection. Predisposingfactors (e.g., solid tumor), foul odor of lesion or drainage, gas ordiscoloration in tissue, and tissue necrosis, gangrene, or abscess point towarda narrowed differential diagnosis. Gas gangrene is commonly caused byclostridial species (e.g., C. perfringens). However, Gram-negativebacteria, which are much more common with surgical infections, may, rarely,cause gas in mixed infections of soft tissue. Gram-positive organisms (e.g., Strep.pyogenes, Staph. aureus) also commonly cause postsurgical infections, butusually not gas gangrene. • Gram strain. Typical bacterialmorphologies are suggestive of anaerobes. • Cultures of pus or wound aspirate onselective and nonselective media • Aerobic culture. “Sterile pus” (no growth)indicates anaerobes • Selective anaerobic cultures and speciesidentification
【google翻译】 理由:病史和体检结果应该引起怀疑厌氧菌感染。诱发因素(例如,固体肿瘤病变或排水),难闻的气味,气体或变色的组织,组织坏死,坏疽,或脓肿指向一个狭窄的鉴别诊断。气性坏疽的常见原因梭菌物种(如产气荚膜梭菌)。然而,革兰阴性菌,更常见的是与外科手术感染,可能很少,导致气体在混合感染的软组织。革兰阳性菌(如链球菌,化脓性链球菌,金黄色葡萄球菌)也通常导致手术后感染,但通常不气性坏疽。
•革兰株。典型的细菌形态提示厌氧菌。•在选择性和非选择性的平板培养脓液或伤口分泌物•需要培养。 “无菌脓”(没有增长)表示厌氧菌•选择性厌氧培养和物种鉴定
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