Objective: We analyze the characteristics of Clostridioides difficile (C. difficile) infection among diarrhea patients in Kunming from 2018 to 2020 and provide evidence for follow-up surveillance and prevention. Methods: A total of 388 fecal samples of diarrhea patients from four sentinel hospitals in Yunnan Province from 2018 to 2020 were collected. Real-time quantitative PCR was used to detect the fecal toxin genes of C. difficile. The positive fecal samples isolated the bacteria, and isolates were identified by mass spectrometry. The genomic DNA of the strains was extracted for multi-locus sequence typing (MLST). The fecal toxin, strain isolation, and clinical patient characteristics, including co-infection with other pathogens, were analyzed. Results: Among the 388 fecal samples, 47 samples with positive reference genes of C. difficile were positive, with a total positive rate of 12.11%. There were 4 (8.51%) non-toxigenic and 43 (91.49%) toxigenic ones. A total of 18 strains C. difficile were isolated from 47 positive specimens, and the isolation rate of positive specimens was 38.30%. Among them, 14 strains were positive for tcdA, tcdB, tcdC, tcdR, and tcdE. All 18 strains of C. difficile were negative for binary toxins. The MLST results showed 10 sequence types (ST), including 5 strains of ST37, accounting for 27.78%; 2 strains of ST129, ST3, ST54, and ST2, respectively; and 1 strain of ST35, ST532, ST48, ST27, and ST39, respectively. Fecal toxin gene positive (tcdB+) results were statistically associated with the patient's age group and with or without fever before the visit; positive isolates were only statistically associated with the patient's age group. In addition, some C. difficile patients have co-infection with other diarrhea-related viruses. Conclusions: The infection of C. difficile in diarrhea patients in Kunming is mostly toxigenic strains, and the high diversity of strains was identified using the MLST method. Therefore, the surveillance and prevention of C. difficile should be strengthened.
目的： 对2018-2020年昆明地区腹泻患者中艰难梭菌感染特征进行分析，为后续监测和防治提供数据支持。 方法： 收集2018-2020年云南省4家哨点医院腹泻患者粪便标本共388份，使用实时荧光定量PCR方法进行艰难梭菌粪便毒素基因检测，对结果阳性的粪便标本进行菌株的分离，用基质辅助激光解析电离飞行时间质谱鉴定菌株。提取分离菌株的基因组DNA进行多位点序列分型（MLST）。分析毒素阳性和菌株分离阳性与患者的临床特征以及艰难梭菌阳性与其他病原共感染的情况。 结果： 388份粪便标本中，艰难梭菌内参tpi基因阳性标本47份，总阳性率为12.11%。其中，非产毒艰难梭菌4份（8.51%），产毒艰难梭菌43份（91.49%）。47份阳性标本分离得到18株艰难梭菌，阳性标本的分离率为38.30%。其中tcdA、tcdB、tcdC、tcdR和tcdE基因均为阳性的菌株14株。18株艰难梭菌的二元毒素均为阴性。所有分离菌株的MLST结果共形成10种序列型（ST），其中ST37型5株（27.78%）；ST129、ST3、ST54和ST2型各2株；ST35、ST532、ST48、ST27和ST39型各1株。粪便毒素基因阳性（tcdB+）结果与患者年龄、就诊前发热差异有统计学意义；菌株分离阳性仅与患者年龄差异有统计学意义。同时，部分腹泻患者存在艰难梭菌与其他腹泻病毒共感染的情况。 结论： 昆明地区腹泻患者中艰难梭菌的感染多为产毒株，MLST结果具有高度的离散特征，应加强开展艰难梭菌的监测和预防。.