Molecular Characteristics And Infection Risk Factors Of Clostridium Difficile In A Hospital In Ningxia

Objective At present,the epidemiology of Clostridium difficile infection(CDI)in Ningxia has not been reported.This study aims to understand the molecular epidemiology and risk factors of CDI in patients with clinical diarrhea during a period of time in the General Hospital of Ningxia Medical University.Method Collect 530 diarrhea stool specimens from the General Hospital of Ningxia Medical University from Jan 1st.2019 to Dec 1st.2020,and conduct anaerobic culture of Clostridium difficile(CD),matrix-assisted laser desorption ionization time-of-flight mass spectrometer(MALDI-TOF MS)identification,use common PCR method to detect CD toxin genes(tcd A,tcd B,cdt A and cdt B),perform multilocus sequence typing(MLST),and use the software Bio Num-erics BN7.5cn for cluster analysis.Construct evolutionary tree,analyze homology.Further collect patient clinical data,conduct a1:2 case-control study,use SPSS26.0 software to perform statistical analysis on all data,Single factor analysis screened out meaningful items(P<0.05),and screen independent risk factors.And calculate its OR value and 95% confidence interval(95% CI).Results A total of 38 CD strains were detected in 530 diarrhea stools,and 36toxin-producing CD strains(6.8%,36/530),of which 5 strains of tcd A-tcd B+ strains(13.9%,5/36),29 strains of tcd A+tcd B+ strains(80.5 %,29/36),two strains of tcd A+tcd B-(5.5%,2/36).No binary toxin was detected in all strains.There were 36 CDI patients,24 males and12 females,with an average age of 51.1±13.5 years old,5 persons(13.9%)≥65 years old;the positive rate of CDI was higher in ICU,nephrology,and hematology,which were 33.3%(1/3),18.8%(3/16)and 14.3%(2/14).According to MLST analysis,there are 18 ST types in all CDs.The main types ST2,ST42,ST54 account for 10.5%(4/38),followed by ST3,ST8,ST35 and ST102,all accounting for 7.9%(3/38).The ST types of CD are scattered.1: 2 The final multivariate logistics regression analysis of the case-control study showed:hospitalization history within six months(OR 5.61,95%CI 1.52 ～ 20.72,P=0.010),gastrointestinal diseases(OR 4.24,95%CI 1.19～15.12,P=0.026)and liver and gallbladder diseases(OR 6.25,95%CI 1.67～23.41,P=0.006)is an independent risk factor for CDI.Conclusion The CD infection rate in the General Hospital of Ningxia Medical University(6.8%,36/530)is slightly lower than other areas in China.The toxin gene of Clostridium difficile is mainly tcd A+tcd B+,and no binary toxin strains have been detected.The ST type is relatively dispersed,mainly ST2,ST42 and ST54,which are more consistent with other regions in China.In order to prevent Clostridium difficile infection,it is recommended that patients with hospitalization experience within six months,and risk factors for gastrointestinal diseases should be clinically identified early to be alert to the occurrence of CDI.