Gas-producing perianal abscess raises the possibility of clostridial infection, with Clostridium perfringens being the most common causative agent, which is highly lethal if untreated timely. As the treatment of clostridial infections often differs from that of non-clostridial infections, which they may closely resemble, the importance of accurate pathogenic organism identification cannot be overemphasized. The 16S rDNA of bacteria is highly conserved within a species and among species of the same genus but demonstrates substantial variation between different species, thus making it a suitable genomic candidate for bacterial detection and identification. Here, we report the case of a 53-year-old patient who was admitted to the hospital for a gas-producing perianal abscess. The patient was managed with ceftizoxime and ornidazole and then received debridement and drainage at the lesion on the second day after admission. The bacterial cultures of the patient isolates from the debridement showed a coinfection of Escherichia coli and Enterococcus faecium. Although perianal redness and swelling subsided obviously after the surgery, the patient was febrile to 38.3℃ with his left upper thigh red and swollen, aggravated with tenderness and crepitus. Considering insufficient debridement and the risk of incorrect identification of pathogens, a second debridement and drainage were performed 4 days after the primary operation, and 16S rDNA sequencing of the isolates implicated Clostridium perfringens infection. Given the discrepancies in diagnostic results and the treatment outcomes, Enterococcus faecium was identified as sample contamination, and a diagnosis of coinfection of Clostridium perfringens and Escherichia coli in gas-producing perianal abscess was confirmed. The patient was then successfully treated with meropenem and vancomycin and was discharged at 27 days of admission. This case represents the first report of coinfection of both clostridial and non-clostridial organisms in gas-producing perianal abscess and the first case reporting the use of 16S rDNA sequencing in the diagnosis of perianal abscess. Timely pathogen identification is critical for treating gas-producing perianal abscess and an antibiotic regimen covering both aerobic and anaerobic organisms is recommended before true pathogens are identified.

中文翻译：

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产气性肛周脓肿经16S rDNA测序诊断产气荚膜梭菌与大肠杆菌共感染一例

产气性肛周脓肿增加了梭菌感染的可能性，产气荚膜梭菌是最常见的病原体，如果不及时治疗，是高度致命的。由于梭菌感染的治疗通常不同于非梭菌感染，它们可能非常相似，因此不能过分强调准确识别病原体的重要性。细菌的 16S rDNA 在一个物种内和同一属的物种之间高度保守，但在不同物种之间表现出显着差异，因此使其成为细菌检测和鉴定的合适基因组候选物。在这里，我们报告了一名 53 岁患者的病例，该患者因产气性肛周脓肿入院。患者接受头孢唑肟和奥硝唑治疗，入院后第二天接受病灶清创引流。从清创术中分离出的患者细菌培养物显示大肠杆菌和屎肠球菌共感染。术后虽然肛周红肿明显消退，但患者仍发热至38.3℃，左大腿上部红肿，加重，压痛和捻发音。考虑到清创不充分和病原体识别错误的风险，在初次手术后4天进行了第二次清创和引流，分离株的16S rDNA测序涉及产气荚膜梭菌感染。鉴于诊断结果和治疗结果的差异，粪便肠球菌被确定为样本污染，并确认产气性肛周脓肿中产气荚膜梭菌和大肠杆菌共感染的诊断。患者随后成功接受美罗培南和万古霉素治疗，并在入院 27 天后出院。该病例是产气性肛周脓肿中梭菌和非梭菌共感染的首例报告，也是首例使用 16S rDNA 测序诊断肛周脓肿的病例。及时识别病原体对于治疗产气性肛周脓肿至关重要，在识别真正的病原体之前，建议采用涵盖需氧和厌氧生物的抗生素治疗方案。诊断为产气性肛周脓肿产气荚膜梭菌和大肠杆菌共感染。患者随后成功接受美罗培南和万古霉素治疗，并在入院 27 天后出院。该病例是产气性肛周脓肿中梭菌和非梭菌共感染的首例报告，也是首例使用 16S rDNA 测序诊断肛周脓肿的病例。及时识别病原体对于治疗产气性肛周脓肿至关重要，在识别真正的病原体之前，建议采用涵盖需氧和厌氧生物的抗生素治疗方案。诊断为产气性肛周脓肿产气荚膜梭菌和大肠杆菌共感染。患者随后成功接受美罗培南和万古霉素治疗，并在入院 27 天后出院。该病例是产气性肛周脓肿中梭菌和非梭菌共感染的首例报告，也是首例使用 16S rDNA 测序诊断肛周脓肿的病例。及时识别病原体对于治疗产气性肛周脓肿至关重要，在识别真正的病原体之前，建议采用涵盖需氧和厌氧生物的抗生素治疗方案。该病例是产气性肛周脓肿中梭菌和非梭菌共感染的首例报告，也是首例使用 16S rDNA 测序诊断肛周脓肿的病例。及时识别病原体对于治疗产气性肛周脓肿至关重要，在识别真正的病原体之前，建议采用涵盖需氧和厌氧生物的抗生素治疗方案。该病例是产气性肛周脓肿中梭菌和非梭菌共感染的首例报告，也是首例使用 16S rDNA 测序诊断肛周脓肿的病例。及时识别病原体对于治疗产气性肛周脓肿至关重要，在识别真正的病原体之前，建议采用涵盖需氧和厌氧生物的抗生素治疗方案。