OBJECTIVE To understand the molecular epidemiological characteristics,antimicrobial sensitivity and resistance mechanisms of Clostridioides difficile in Xi'an region,and provide data support for the prevention and control of C.difficile infection and the rational clinical use of antibiotics.METHODS A total of 87 strains of C.difficile,which were successfully isolated from stool samples collected from 6 hospitals from Oct.2018 to Dec.2022,were tested for virulence genes,population structure and genetic diversity were detected by Multilocus sequence typing(MLST)and Ribotyping(RT)methods,the drug sensitivity was detected by Etest,additionally,amino acid variations in the quinolone resistance-determining regions GyrA and GyrB were detected.RESULTS There were 41 strains(62.12％)with the genotype A+B+CDT—,23 strains(34.85％)with the genotype A-B+CDT—,and 2 strains(3.03％)with the genotype A+B+CDT+.MLST was divided into 25 ST types,and the main types were ST3,ST42 and ST39.There were 37 RT types,mainly were RT012,RT106 and RT001.All strains were sensitive to vancomycin and metronidazole,and the resistance rates to ciprofloxacin,levofloxacin and moxifloxacin were 90.80％,28.73％and 21.84％,respectively.GyrA contains two amino acid variations at Thr82-Ile and Asp205-Glu,and GyrB contains 6 amino acid variations.CONCLUSIONS The predominant toxin-producing strain of C.difficile in Xi'an is of A+B+CDT-genotype and the primary molecular types are ST54/RT012,ST42/RT106,ST3/RT001 and ST37/RT017.No strains resistant to vancomycin or metronidazole are detected.Amino acid variations in GyrA or GyrB of C.difficile are associated with quinolone resistance.To ef-fectively prevent the outbreak of C.difficile infection,it is crucial to enhance molecular epidemiology studies and strengthen antimicrobial resistance surveillance efforts.

OBJECTIVE To understand the molecular epidemiological characteristics,antimicrobial sensitivity and resistance mechanisms of Clostridioides difficile in Xi'an region,and provide data support for the prevention and control of C.difficile infection and the rational clinical use of antibiotics.METHODS A total of 87 strains of C.difficile,which were successfully isolated from stool samples collected from 6 hospitals from Oct.2018 to Dec.2022,were tested for virulence genes,population structure and genetic diversity were detected by Multilocus sequence typing(MLST)and Ribotyping(RT)methods,the drug sensitivity was detected by Etest,additionally,amino acid variations in the quinolone resistance-determining regions GyrA and GyrB were detected.RESULTS There were 41 strains(62.12％)with the genotype A+B+CDT—,23 strains(34.85％)with the genotype A-B+CDT—,and 2 strains(3.03％)with the genotype A+B+CDT+.MLST was divided into 25 ST types,and the main types were ST3,ST42 and ST39.There were 37 RT types,mainly were RT012,RT106 and RT001.All strains were sensitive to vancomycin and metronidazole,and the resistance rates to ciprofloxacin,levofloxacin and moxifloxacin were 90.80％,28.73％and 21.84％,respectively.GyrA contains two amino acid variations at Thr82-Ile and Asp205-Glu,and GyrB contains 6 amino acid variations.CONCLUSIONS The predominant toxin-producing strain of C.difficile in Xi'an is of A+B+CDT-genotype and the primary molecular types are ST54/RT012,ST42/RT106,ST3/RT001 and ST37/RT017.No strains resistant to vancomycin or metronidazole are detected.Amino acid variations in GyrA or GyrB of C.difficile are associated with quinolone resistance.To ef-fectively prevent the outbreak of C.difficile infection,it is crucial to enhance molecular epidemiology studies and strengthen antimicrobial resistance surveillance efforts.

Objective:To analyze the medication law of TCM oral prescriptions in the treatment of postherpetic neuralgia (PHN).Methods:The effective cases and clinical studies about TCM oral prescriptions in the treatment of PHN were retrieved from CNKI, Wanfang Data, VIP, and CBM from January 1, 2002 to December 31, 2021. The medication frequency and drug properties were counted through the Ancient and Modern Medical Record Cloud Platform, and correlation analysis, cluster analysis and complex network analysis were performed.Results:A total of 233 articles were included, involving 243 prescriptions and 191 kinds of Chinese materia medica. There were 20 kinds of Chinese materia medica with frequency >40, most of which have the efficacy of promoting blood circulation to remove blood stasis. The Chinese materia with heat-clearing and detoxifying efficacy were also often used. The properties were mainly warm, mild, slight cold, and cold, tastes were mainly bitter, pungent and sweet, and meridians were mainly liver, spleen and heart meridians. The association rule analysis was used to obtain 15 commonly used TCM groups. The commonly used Chinese materia medica could be clustered into 4 categories. The core prescription obtained by complex network analysis was Angelicae Sinensis Radix, Glycyrrhizae Radix et Rhizoma, Corydalis Rhizoma, Bupleuri Radix, Carthami Flos, Paeoniae Radix Alba, Persicae Semen, Chuanxiong Rhizoma, and Rehmanniae Radix.Conclusion:TCM oral prescriptions for the treatment of PHN put promoting blood circulation to remove blood stasis and activating meridians to stop pain in priority, taking into account the clearing heat, regulating qi and blood.

Objective:To characterize the epidemiology of hand, foot and mouth disease (HFMD) cases caused by coxsackievirus group A type 6 (CV-A6) in Xi’an from 2016 to 2020 and provide evidence for the prevention and control of HFMD.Methods:The enterovirus (EV) types were identified using real-time RT-PCR. The data of HFMD cases were collected from the National Notifiable Infectious Diseases Reporting System of China Center for Disease Control and Prevention. Descriptive epidemiological method were used to analyze the distributions and the data were statistically analyzed with Excel 2007 and SPSS 18.0.Results:In the 4 034 HFMD cases, 17.85% had enterovirus group A type 71 (EV-A71) infections, 23.92% had coxsackievirus group A type 16 (CV-A16) infections, and 47.79% had other EV infections. 2 571 HFMD cases were randomly selected, including 1 268 other EV positive cases. The detection rate of CV-A6 in HFMD cases was 34.73% (893/2 571), and the constituent ratio of CV-A6 in other EV positive cases was 70.43% (893/1 268). The cases mainly occurred in children aged≤5 years (95.18%), more boys were affected than girls (1.47∶1). HFMD caused by CV-A6 was concentrated in April to June. Compared with EV-A71 and CV-A16, the clinical classification had significant difference in CV-A6 group ( χ2=139.55, P<0.001), but the ratio of sex and age-group had no significant difference ( F=2.74, P=0.065; χ2=2.43, P=0.297). Conclusions:The predominant pathogen of HFMD in Xi’an from 2016 to 2020 were other EV, among which CV-A6 accounted for the highest proportion in other EV positive cases. It is necessary to strengthen the prevention and control of HFMD caused by CV-A6 and carry out the surveillance for various pathogens of HFMD.

Objective:To explore the positive rates of 2019-nCoV nucleic acid at different time of courses of COVID-19.Methods:Patients with confirmed COVID-19 were enrolled in this study. Nasal and throat swabs were collected from different courses of disease. Real-time RT-PCR was used to detect 2019-nCoV nucleic acid.Results:From January 23 to February 20, 2020, a total of 120 confirmed cases of COVID-19 were reported in Xi’an, and 85 cases(70.83%) were positive in first detection. The COVID-19 cases included consistently nucleic acid positive and intermittently nucleic acid positive patients. 2019-nCoV nucleic acid could be detected in incubation period, and the longest observed duration of nucleic acid positive in this study was 26 days. The positive rate of 2019-nCoV nucleic acid was up to 84.21% on the 6th day, and the positive rate decreased as time passed during the course of COVID-19. Three patients (2.86%) were tested positive for 2019-nCoV nucleic acid again in nasal and throat swabs after discharge.Conclusions:The positive rate of 2019-nCoV nucleic acid was higher in the early stage of disease. 2019-nCoV nucleic acid can be detected in incubation period, and virus shedding may last for a long period.

Objective:To analyze the clinical characteristics of HBV-related liver cirrhotic patients with low viral load.Methods:A retrospective analysis on 481 inpatients with HBV-related cirrhosis with low viral load [HBV DNA≤2 000 IU/ml (10 4 copies/ml)] general condition, virological indicators, liver function-related indicators, complications, and incidence of complications were analyzed. The t-test was used to compare the average measurement data, and the χ2 test was used to compare the count data. Results:481 cases were mainly male (male/female: 324/157), aged 20-83 (53.31 ± 11.67) years old. Han nationality accounted for 71.518%. 386 cases were HBsAg positive. 391 cases were HBeAg positive, and 140 cases were HBV DNA positive. The average value of bilirubin, albumin, alanine aminotransferase, aspartate aminotransferase, platelets, and prothrombin were 50.59 ± 91.25 (μmol/L), 33.68 ± 7.5 (g/L), and 60.66 ± 106.95(U/L), 63.37 ± 86.19(U/L), 106.65 ± 83.22(×10 9/L), 68.82% ± 25.33%, respectively. CTP class A/B/C had 220/150/111 cases. The average values of CTP, MELD, APRI and FIB-4 were 7.61 ± 2.58, 10.98 ± 5.79, 2.34 ± 3.56, 6.91 ± 8.04, respectively. The overall incidence of complications in HBV-related cirrhotic patients with low viral load, HBV DNA negative, HBV DNA positive, HBsAg negative, and HBsAg positive were 80.0%, 82.7%, 73.6%, 85.3%, and 78.8%, respectively. Among them, 283 cases (58.84%), 197 cases (55.77%), 86 cases (61.43%), 52 cases (54.74%) and 231 cases (59.84%) were of hypersplenism, and 267 cases (55.51%), 197 cases (55.77%), 70 cases (50.00%), 56 cases (58.95%), and 211 cases (54.66%) were of esophagogastric varices. There were 59 cases (12.27%), 48 cases (14.08%), 11 cases (7.86%), 12 cases (12.63%), and 47 cases (12.18%) of rupture of esophageal and gastric varices, respectively. 202 cases (42.00%), 147 cases (43.11%), 55 cases (39.29%), 42 cases (44.21%), and 160 cases (41.45%) were of ascites, respectively. 17 cases (3.53%), 12 cases (3.52%), 5 cases (3.5%), 2 cases (2.11%), 15 (3.89%) cases were of hepatic encephalopathy, respectively. There were 6 cases (1.25%), 3 cases (0.88%), 3 cases (2.14%), 0 cases (0%), 6 cases (1.55%) of liver cancer. 29 cases (6.03%), 21 cases (6.16%), 8 cases (5.71%), 9 cases (9.47%) and 20 cases (5.18%) were of portal vein thrombosis. Compared with the overall incidence of complications, 341 HBV DNA-negative patients and 95 HBsAg-negative patients still had higher incidence of complications. The patients were grouped by age, and in < 40 years old, 40-50 years old, and > 50 years old, the overall complications were 80.8% in 42 cases, 76.8% in 116 cases and 81.7% in 227 cases, and the difference was not statistically significant. Conclusion:HBV infection patients with low viral load, and those whose HBsAg has disappeared, are still at risk of developing liver cirrhosis and even serious complications, and whether such population need antiviral therapy and benefit from it deserves further research.

Objective To understand the distribution of novel coronaviruses in the external environment of confirmed COVID-19 cases. Methods Environmental surface swab specimens such as bed rails, doorknob, closestool, hand washing sink, table, locker,ward pager, mobile phone, cup, clothes, were collected from the sentinel hospital of COVID-19, and samples were collected for the nucleic acid detection by RT-PCR. Results A total of 150 environmental samples were collected from 30 confirmed COVID-19 cases, 6 samples were determined to be novel coronaviruses postive (positive rate 4.00%). The total 14 mobile phone showed 3 novel coronaviruses positive.Among the 30 confirmed COVID-19 cases, 6 cases (positive rate 20.00%)were found novel coronaviruses in the external environment. Conclusions Novel coronaviruses exists in external environment of confirmed COVID-19 cases, which indicates the potential risk of COVID-19 infection.

Objective: To understand the etiological and clinical characteristics of children with severe hand, foot and mouth disease (HFMD) in Xi′an in 2018, and to provide the evidence for clinical diagnosis and treatment. Methods: The children with severe HFMD admitted at Xi′an Children′s Hospital from January to December 2018 were selected as the research objects.Clinical data were collected, and the anal swab were detected by adopting real time(RT)-polymerase chain reaction(PCR). Results: Ninety-five cases of HFMD were treated in Xi′an Children′s Hospital in 2018, of which 92 cases were severe and 3 cases were critical.Eighty-seven cases were positive for enterovirus nucleic acid, 30 cases were enterovirus 71(EV71)(31.6%), 39 cases were coxsackievirus A6(CA6) (41.0%), 3 cases were CA16(3.2%), 2 cases were CA10(2.1%) and 13 cases were other enteroviruses (13.7%). Among 95 patients, the ratio of male to female was 1.1∶1.0; the peak period of incidence of HFMD was from May to July, and the main age of onset of severe HFMD was under 3 years old.The main clinical manifestations were mental retardation, vomiting, irritability, lethargy and convulsion.Severe cases of CA6 are prone to convulsion.The main form of rash in CA6 cases was bullous rash, and demethylation may occur in recovery period.The rash in EV71 cases was small, thick, hard and few.After active treatment, only one child with EV71 infection died because of severe cerebral dysfunction, frequent convulsions and neurogenic pulmonary edema.The other child was discharged with hemiplegia and language dysfunction.The other severe children were cured and discharged from hospital. Conclusions In 2018, CA6 was the main pathogen of severe HFMD in Xi′an, with bullae was the main manifestation of skin rash, and nail removal could occur during convalescence.Critical and death cases were still caused by EV71.

Objective: To analyze the epidemiological characteristics and etiologic agent of herpangina in Xi’an in 2016. Methods: Herpangina epidemiological data and random stool samples were collected from two sentinel hospitals. The data were statistically analyzed with Excel and SPSS 18.0 and samples were detected and enteroviruses were genotyped using real-time PCR and RT-snPCR. Results: Totally 421 cases were reported and the male-to-female ratio was 1.54∶1, age ranged from 3 month to 13 years, and 90.50% were under three years of age. Herpangina showed semiannual peaks in April to October, of which the highest was in June (23.75%, 100/421). Lab result showed that 71.05% were EV positive out of 152 samples, and further genotyping indicated 60 were non-typable, and other 48 comprised of eight serotypes of EV including EV-A71, CV-A4, CV-A5, CV-A6(6.48%), CV-A10(23.15%), CV-A12, CV-A16 and CV-B3. Conclusions Male children under 3 years of age were the main population and herpangina cases were most frequently reported in June in Xi’an in 2016. CV-A6 and CV-A10 were more frequently detected in the typable ones.

Objective To evaluate the application of modified MELD score based on the estimated glomerular filtration rate (eGFR) in the prognosis of patients with liver failure.Methods Clinical data of 558 patients with liver failure admitted in the First Affiliated Hospital of Xinjiang Medical University from December 2001 to September 2017 were retrospectively analyzed.Among all patients,238 cases survived (survival group) and 320 died (fatal group) within 3 months.The eGFR was used in the modified model for end stage liver disease (MELD) instead of serum creatinine.Cox regression analyses were fitted with modified MELD or MELD scores by SAS 9.0 PHREG.The receiver operating characteristic (ROC) curve was generated and the values of modified MELD score and MELD score in predicting the prognosis of patients with liver failure in 3 months were compared.Kaplan-Meier method was used to analyze the survival rate of patients with liver failure.Results Cox regression analysis showed that total bilirubin,international normalized ratio (INR) and eGFR were independent prognostic factors for patients with liver failure.The fitted MELD modified score =4.07 × ln total bilirubin (mg/dL) + 12.99 × ln INR-8.32 × ln eGFR.The area under the ROC curve (AUC) of the modified MELD score and the MELD score were 0.814 and 0.757,respectively,and the sensitivity and specificity of the modified MELD score were 70.0％ and 71.4％,respectively.The predictive power of modified MELD scores in patients with liver failure was better than MELD score (Z =4.47,P ＜ 0.01).The 3-month survival rate of patients with modified MELD score ＜-15.38 was significantly higher than those with modified MELD score ≥-15.38 (x2 =99.20,P ＜ 0.01).Conclusions eGFR is an independent risk factor for the prognosis of patients with liver failure.The modified MELD score including eGFR and excluding etiological factors can be more effective and more accurate for prognosis of patients with liver failure.