Sun Yang, Bai Haotian, Qu Ji, Liu Jichao, Wang Jincheng, Du Zhenwu, Feng Linlin
Orthopaedic Medical Center, the Second Hospital of Jilin University, Changchun, Jilin, China.
The Engineering Research Centre of Molecular Diagnosis and Cell Treatment for Metabolic Bone Diseases of Jilin Province, Changchun, Jilin, China.
Gut Pathog. 2021 Oct 13;13(1):61. doi: 10.1186/s13099-021-00457-x.
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.
产气性肛周脓肿增加了梭菌感染的可能性，其中产气荚膜梭菌是最常见的病原体，如果不及时治疗，其致死率很高。由于梭菌感染的治疗方法通常与非梭菌感染不同，而它们可能非常相似，因此准确鉴定致病生物体的重要性再怎么强调也不为过。细菌的16S rDNA在一个物种内以及同一属的物种之间高度保守，但在不同物种之间存在很大差异，因此使其成为细菌检测和鉴定的合适基因组候选物。
在此，我们报告一例53岁患者，因产气性肛周脓肿入院。患者接受头孢唑肟和奥硝唑治疗，入院后第二天在病变处进行清创引流。清创术中患者分离出的细菌培养显示大肠埃希菌和粪肠球菌混合感染。虽然术后肛周红肿明显消退，但患者发热至38.3℃，左大腿上部红肿，压痛和捻发音加重。考虑到清创不彻底以及病原体鉴定错误的风险，在初次手术后4天进行了第二次清创引流，分离株的16S rDNA测序表明产气荚膜梭菌感染。鉴于诊断结果和治疗结果的差异，粪肠球菌被确定为样本污染，产气性肛周脓肿产气荚膜梭菌和大肠埃希菌混合感染的诊断得到证实。患者随后接受美罗培南和万古霉素成功治疗，入院27天后出院。
本病例是产气性肛周脓肿中梭菌和非梭菌生物体混合感染的首例报告，也是首例报告使用16S rDNA测序诊断肛周脓肿的病例。及时鉴定病原体对于治疗产气性肛周脓肿至关重要，在确定真正的病原体之前，建议使用覆盖需氧菌和厌氧菌的抗生素方案。
