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ObjectiveTo analyze the biofilm forming ability and antimicrobial resistance of  coagulasenegative staphylococcus（CNS）isolated from  blood culture.Methods126 strains of CNS from blood culture in a hospital were collected, biofilm formation was analyzed with  96well polystyrene plates, and polymerase chain reaction (PCR) was applied to detect mecA gene, antimicrobial resistance was analyzed.ResultsAmong 126 CNS isolates, 87(69.04%) were positive for biofilm,105 （83.33%）carried mecA gene. The resistant rates of CNS to penicillin, oxacillin, and erythromycin were all＞ 80%, none of the strains were resistant to linezolid, quinupristin / dalfopristin, vancomycin, and tigecycline; resistant rates of methicillinresistant CNS (MRCNS) to ciprofloxacin, gentamicin,levofloxacin, penicillin, rifampicin, and compound sulfamethoxazole were all higher than  methicillinsusceptible CNS(MSCNS) (all P＜0.05). Of MSCNS, 2 carried mecA gene.ConclusionCNS isolated from blood have strong biofilm forming ability, most are MRCNS and with multidrug resistance; there are strains with inconsistence of drugresistant  phenotype and genotype.

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ObjectiveTo evaluate serum Slit2 protein level in patients with chronic severe hepatitis B, and the relation with extent of liver damage and prognosis of patients.MethodsIn FebruaryJuly 2014, patients with chronic hepatitis  B(chronic hepatitis group)  and chronic severe hepatitis  B(chronic severe hepatitis group) in an infectious department were observed, healthy volunteers were as control group, and patients in chronic severe hepatitis group were subdivided into recovery subgroup and nonrecovery subgroup based on whether patients had recovered. Serum Slit2 protein, prothrombin activity(PTA),   total bilirubin (TBIL), and  alanine transaminase（ALT）levels were detected and compared.ResultsA total of 157 patients (chronic hepatitis  group, n=93; chronic severe hepatitis group, n=64) and 10 healthy volunteers were included in the study . Slit2 protein levels were significantly different among three groups（F=5.596，P=0.004）, serum Slit2 protein levels in chronic hepatitis group and chronic severe hepatitis group were (4.90±1.07) ng/mL  and (3.09±1.00)ng/mL respectively, both were higher than (2.10±0.60)ng/mL in healthy control group (both P＜0.05); serum Slit2  protein  level in chronic severe hepatitis group was significantly lower than chronic hepatitis group (P＜0.05). Serum Slit2 protein level in nonrecovery subgroup of chronic severe hepatitis group was significantly lower than recovery subgroup (［1.88±0.67］ ng/mL vs ［2.96±1.32］ng/mL, t=2.319,P=0.032). Serum Slit2  protein  level in patients with chronic hepatitis  B was positively correlated with PTA level(r=0.33，P＜0.05), but negatively correlated with serum TBIL level (r=-0.46，P＜0.05) and ALT level （r=-0.32，P＜0.05）.ConclusionSerum Slit2 protein level is an important index which can reflect the prognosis of patients with chronic severe hepatitis, low serum Slit2 level suggests the poor clinical prognosis.

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ObjectiveTo evaluate the effect of  tourniquet on incisional  infection  based on animal model, and evaluate the effect of ischemia preconditioning on incisional  infection, so as to provide experimental basis for the rational use of tourniquet in clinic.Methods100 BALB/c mice were randomly divided into 4 groups, with 25 mice in each group. Group A: tourniquet+methicillinresistant Staphylococcus aureus(MRSA) incisional infection; group B: ischemic preconditioning+MRSA incisional infection ; group C : MRSA incisional infection; group D: blank control. The survival rates, temperature, routine blood testing, and change in soft tissue beside femoral incision were compared among 4 groups.ResultsDuring observation period ,the survival rate in group A was 68%, in group B,C, and D were all 100%,  group A was lower than group B,C, and D (P＜0.05). The temperature at each time point was significantly different among group A, B, and C (P＜0.01); temperature curves of 4 groups were significantly different (P＜0.01); except basal body temperature, temperature at the other  time points among 4 groups were significantly  different(all P＜0.01); routine blood testing results (white blood cell count, total granulocyte count, and total lymphocyte count) among 4 groups  on the third, and seventh day were significantly different(all P＜0.05); on the seventh  day, routine blood testing results of 4 groups all returned to normal level, but group A was slightly higher than group B,C, and D. Section of epithelial tissue revealed that epithelial tissue in group A was not healed，inflammatory response of peripheral tissue was most serious;epithelial tissue in 10 mice in group B was healed，partial peripheral tissue revealed inflammatory response;epithelial tissue in 4 mice in group C was healed，most peripheral tissue revealed inflammatory response.ConclusionMice incisional infection will be aggravated by using lower limb tourniquet, incision healing and body function recovery time will be delayed, even lead to death. Ischemic preconditioning before making an incision model can reduce the severity of incisional infection, and shorten wound healing time.

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ObjectiveTo analyze the positive report time, distribution and antimicrobial resistance of pathogens isolated from blood culture at a hospital, so as to provide laboratory basis for prevention, contro1,and  rational antimicrobial use for bloodstream infection.MethodsFrom January 2013 to January 2015, blood culture specimens of outpatients and inpatients were performed bacterial identification and antimicrobial susceptibility testing, antimicrobial resistance was analyzed.ResultsA total of 1 973 blood culture specimens were sent by clinical departments, 219 (11.10%) of which were isolated pathogens. Most positive blood culture specimens were from department of paediatrics(n=199).  Isolation rates of gramnegative bacteria, grampositive bacteria, and fungi were  44.34% (n=98), 50.23%  (n=111)，and 5.43% (n=12) respectively; the main pathogens was  coagulasenegative staphylococcus (n=53, 23.98%), followed by Escherichia coli (n=39,17.65%), Staphylococcus aureus (n=23, 10.41%), Klebsiella pneumoniae (n=15, 6.79%)，and Pseudomonas aeruginosa (n=13,5.88%), the average positive blood culture  report time of top five pathogens was 1-2 days. The detection rates of extendedspectrum βlactamaseproducing Escherichia coli and Klebsiella pneumoniae accounted for 53.85% and 53.33% respectively, susceptibility of gramnegative bacilli to carbapenems was relatively high（76.92%-100%）; methicillinresistant isolates accounted for 39.13% among Staphylococcus aureus and  64.15% among coagulasenegative staphylococcus, vancomycinresistant  and teicoplaninresistant strains were not found;  resistant rate of Candida glabrata to 5fluorocytosine was 14.29%，but was susceptible to amphotericin B.ConclusionThe major pathogens isolated blood culture are grampositive bacteria,  in order to reduce the emergence of drugresistant strains, clinicians should choose antimicrobial agents according to blood culture results and antimicrobial susceptibility testing results.

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ObjectiveTo  realize detection, antimicrobial resistance, and ward distribution of imipenemresistant Acinetobacter baumannii (IRAB ) from sputum.MethodsAB strains isolated from sputum specimens in a hospital between January 1, 2009 and  September 30, 2013 were analyzed retrospectively.  Ward distribution, antimicrobial resistance, and isolation rates  between  IRAB and nonIRAB strains were compared.Results711 AB strains were isolated from sputum, 442 of which were IRAB, 269 were nonIRAB.AB were mainly distributed in intensive care unit(ICU, 39.10%) and neurology department (25.18%) ; detection rate of IRAB was  significantly higher than nonIRAB in ICU (57.47%［n=254］ vs  8.92%［n=24］,χ2=165.50,P＜0.05)， detection rate of IRAB in ICU was significantly higher than nonICU (91.37% vs 43.42%, χ2=257.29,P＜0.05). Detection rates of IRAB in 2009-2013 increased continuously (25.30%， 36.36%， 74.68%， 65.56%, and 90.07%, respectively). The resistant rate of IRAB to amikacin was low (27.25%)， resistant rates of nonIRAB to amikacin and piperacillin /tazobactam were both low (7.31% and 8.24% respectively);except compound sulfamethoxazole， resistant rates of IRAB to other antimicrobial agents were all significantly higher than nonIRAB strains (all P＜0.05).ConclusionThe detection rate and drug resistant rate of IRAB from sputum are both high,  early culture， early treatment，and early isolation should be carried out to reduce the emergence of multidrugresistant organisms.

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ObjectiveTo survey the retraction of  dental unit waterlines (DUWLs) in medical institutions, and evaluate the influencing factors for retraction of DUWLs.MethodsIn MayNovember 2014, dental chair units(DCUs) in medical institutions in Tianjin City were sampled through systematic random sampling method, retraction volume of DUWLs was detected by independently made detector, the relevant influencing factors were  investigated.ResultsA total of 58 DCUs in 30 medical institutions in 10 districts(counties) of Tianjin  were investigated,the average retraction volume of DUWLs was （103.60±117.85 ）mm3, the qualified rate of retraction volume of DUWLs was 48.28 %（28/58）；length of utilization of DCUs was positively correlated with DUWLs  retraction （r=0.52，P＜0.001）.There were no significant difference in retraction volume of DUWLs among medical institutions in different districts(counties), levels of  medical institutions,DUC brands, and modes of DUC water supply(all P＞0.05).ConclusionThe qualified rate of retraction volume of DUWLs is low, routine maintenance of DUCs needs to be intensified,especially the longterm used DUCs,  contaminatin of DUWLs due to the invalidity of retraction valve should be prevented.

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ObjectiveTo explore the status and influencing factors of surgical site infection (SSI) following laparoscopic surgery in patients in department of general surgery, so as to take effective measures to reduce SSI.MethodsActive monitoring method was used to survey SSI among 401 patients undergoing laparoscopic surgery from January 1, 2013 to December 31, 2013, univariate analysis and multivariate analysis on risk factors for SSI were conducted.ResultsOf 401 investigated patients, 12 (2.99%) developed SSI. Univariate analysis showed that risk factors for SSI in patients with laparoscopic surgery were  elderly patients, emergency operation, infected wound, gastrointestinal tract operation, and grade Ⅳof ASA score (all P＜0.05).Multivariate logistic regression analysis revealed that elderly patients (OR, 5.02［95%CI,1.38-30.25］), emergency operation (OR,4.37 ［95%CI,1.96-28.55］), infected wound (OR,7.27［95%CI,2.54-25.05］), and gastrointestinal tract operation  (OR,8.13 ［95%CI,1.38-18.33］)were high risk factors for SSI following laparoscopic surgery(all P＜0.05).ConclusionThere are multiple factors influencing SSI after laparoscopic surgery, diversified prevention and control measures can effectively reduce the incidence of postoperative SSI.

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ObjectiveTo investigate the incidence and influencing factors for sharp injuries occurred in workers in central sterile supply departments (CSSDs).MethodsIn OctoberNovember 2012, a multicenter crosssectional survey was conducted, a total of 95 workers in CSSDs of 16 hospitals in Hunan Province were surveyed through questionnaires.ResultsA total of 89 workers (93.68%) in CSSDs sustained  sharp injuries, 46 (48.42%) of whom sustained 1-5 times of sharp injuries, 22(23.16%) sustained 6-10 times of sharp injuries, and 11 (11.58%) sustained for at least 10 times of sharp injuries. 81 workers (85.26%) sustained at least one time of sharp injuries one year before survey, 52(54.73%) of whom were injured  by contaminated needles or other sharps. Logistic regression analysis revealed that higher educational background was protective factor for sharp injuries（OR 90%CI: 0.05-0.87）; while poor sleep quality（OR 90%CI: 1.03-17.94）,  frequent touching  sharps（OR 90%CI: 1.11-12.15）, and irrational placing of objects by the other medical stuff (surgeons and nurses in operating rooms) （OR 90%CI: 1.23-16.98) were the risk factors for sharp injuries.ConclusionThe incidence of sharp injuries among workers in CSSDs is high, which is related to personal factors and environmental factors. It is suggested to strengthen staff  training to enhance their awareness of precaution.

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ObjectiveTo investigate in vitro activity of antimicrobial agents against Enterococcus spp. isolated from clinic specimens in a hospital.Methods188 Enterococcus spp. isolates from specimens sent by clinic departments in June 2013July 2014 were identified and performed antimicrobial susceptibility testing.ResultsOf 188 Enterococcus spp. isolates, 119 were Enterococcus faecium(E. faecium), 60 were E. faecalis, and 9 were E. avium, these strains  were mainly isolated from urine (34.57%) and blood specimens(19.15% ).  No daptomycin and linezolidresistant strain was detected;resistant rates of E. faecium to vancomycin was 1.68%, to penicillin，ampicillin，high concentration gentamycin，erythromycin,and levofloxacin were all ＞ 70%; except tetracycline, resistant rates of E.faecalis to the other antimicrobial agents were all lower than E. faecium, resistant rates of E. faecalis to penicillin and ampicillin were 16.67% and 13.33%  respectively.ConclusionDaptomycin has high activity against Enterococcus spp. in this hospital.

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ObjectiveTo explore the incidence of surgical site infection (SSI) and  compliance to bundled intervention measures, and evaluate the effect of bundled interventions on controlling SSI.MethodsFrom October 2013 to September 2014, three types of surgeries (colorectal surgery, abdominal hysterectomy, and femoral neck repair surgery) in 29 hospitals in China were monitored, October 2013 to March 2014 was baseline investigated stage, April 2014 to September 2014 was intervention stage. ResultsA total of 6 166 episodes of surgeries  were monitored, the incidence of SSI was 1.64%, incidence of  SSI following colorectal surgery, abdominal hysterectomy, and femoral neck repair surgery were 4.47%, 1.03%, and 0.21% respectively. The P75 time of three types of surgeries were 3, 2, and 2 hours respectively.Compared with the baseline stage， the compliance to most intervention measures improved after intervention, the largest increase in the compliance to interventions was  disinfection with chlorhexidinecontaining disinfectant at surgical sites of colorectal surgery (increased by 29.09%), followed by preoperative shower of femoral neck repair surgery (increased by 26.24%), preoperative shower  of colorectal surgery(increased by 22.95%),  and skin preparation on the day of operation (increased by 20.75%). Incidences of SSI in three types of surgeries were not significantly different before and after intervention(all P＞0.05).ConclusionThe incidences of SSI are different among different types of surgeries，the compliance to most bundled intervention measures has improved to some extent after intervention, but effectiveness of intervention measures needs to be further observed.

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ObjectiveTo understand the constituent and antimicrobial  resistance of pathogens causing intraabdominal infection,  so as to provide reference for clinical treatment of intraabdominal infection.MethodsPathogens causing intraabdominal infection in patients in a hospital from January 2011 to December 2013 were identified and performed antimicrobial susceptibility testing, and results were  analyzed with WHONET5.6 software.ResultsA total of 810 nonrepeated strains were isolated from 15 946 intraabdominal specimens, isolation rate was 5.08%; isolation rates of gramnegative bacilli, grampositive bacteria, and fungi were  59.88%(n=485), 33.95% (n=275), and 6.17%(n=50) respectively;  the top five pathogens were Escherichia coli (E. coli,24.20%), Enterococcus faecium (E. faecium, 15.06%), Acinetobacter baumannii (A. baumannii, 8.89%), Klebsiella pneumoniae (K. pneumoniae, 7.66%), and coagulase negative staphylococcus (CNS, 6.91%). The detection rates of extendedspectrum β1actamases(ESBLs) in E. coli and K. pneumoniae were 59.18％ and 32.79％ respectively. Enterobacteriaceae were still highly sensitive to imipenem, but carbapenemresistant Enterobacteriaceae strains accounted for 4.08%-6.67% ; multidrugresistant A. baumannii accounted for  52.11%（37/71）, methicillinresistant strains in Staphylococcus aureus and CNS accounted for 53.57％（15/28） and 71.43％（40/56） respectively, resistance rate of E. faecium to vancomycin was 8.26%.ConclusionThe main pathogens causing intraabdominal infection in this hospital are gramnegative bacilli, especially E. coli, while E. faecium is the most common grampositive pathogen, antimicrobial resistance of bacteria is still serious.

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ObjectiveTo investigate the incidence and risk factors for surgical site infection (SSI) in clean wound orthopedics surgery.MethodsSSI among patients receiving clean wound orthopedic surgery from April 1 to September 30 in 2014 were monitored, risk factors for SSI were analyzed.ResultsA total of 665 patients were monitored, 14 cases(2.11%)  of SSI occurred. Univariate analysis  showed that types of skin, skin preparation modes, and ASA score were risk factors for SSI in clean wound orthopedic surgery  (all P＜0.05）. Multivariate logistic analysis revealed that conventional skin preparation,ASA score ≥ grade Ⅱ, and duration of operation ≥90 minutes were independent risk factors for SSI in patients receiving clean wound orthopedic surgery (OR［95%CI］, 3.96［1.07-14.70］,6.45［1.97-21.11］, and 4.08［1.35-12.30］ respectively）.ConclusionThe improved method of skin preparation, grade I ASA score, and shortening duration of operation can reduce the incidence of SSI in clean wound orthopedic surgery, on the basis of improving the autoimmunization of patients, strengthening  prevention and control of healthcareassociated infection can reduce the incidence of SSI in clean wound orthopedic surgery.

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ObjectiveTo investigate healthcareassociated infection(HAI) in different departments in a children’s hospital, and provide scientific basis for effective prevention and control of HAI in children.MethodsBy bedside visiting and medical record reviewing, survey on HAI prevalence rate was conducted among hospitalized patients in a given day in 2012, 2013, and 2014 respectively, and surveyed data of three years were analyzed.ResultsHAI prevalence rates in 2012, 2013, and 2014 were 6.52%, 5.59%, and 5.85% respectively, there was no significant  difference (χ2=1.02, P=0.60); the average HAI prevalence rate in three years  was 5.98%, there was significant difference in average HAI prevalence rate among different departments（χ2=291.83，P＜0.001）, the top 4 departments of HAI prevalence rate was hematology (27.49%), cardiothoracic surgery (21.13%), neonatal intensive care unit (16.43%), and pediatric intensive care unit (12.76%); the main infection sites were lower respiratory tract (58.44%), upper respiratory tract (22.63%), and  gastrointestinal tract (6.58%); the main pathogens causing HAI was Klebsiella pneumoniae(n=32,28.32%), followed by Acinetobacter baumannii  (n=9,7.96%),  Escherichia  coli (n=9,7.96%),and Pseudomonas aeruginosa (n=7, 6.19%).ConclusionStrengthening prevention and control intervention of HAI in high risk departments has important significance to reduce the incidence of HAI in children’s hospital.

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ObjectiveTo understand the specimen sources, clinical characteristics, and antimicrobial resistance of Burkholderia cepacia(B. cepacia) isolated from infected patients  in intensive care unit(ICU), so as to provide reference for guiding rational use of antimicrobial agents.MethodsClinical data of patients with B. cepacia infection in an ICU between 2011 and 2014 were analyzed retrospectively,  antimicrobial resistance of  strains was analyzed.ResultsA total of 267 B. cepacia strains were isolated, the major specimen sources  were sputum （80.15%,n=214）,  blood（14.23%,n=38）,and urine（3.37%,n=9）. Antimicrobial susceptibility testing results revealed that B. cepacia had multiple resistance, and was naturally resistant to multiple clinically used  antimicrobial agents, such as ampicillin, cefazolin, ampicillin/sulbactam, nitrofurantoin, and cefuroxime,resistant rates  were all 100%; resistant rates to ceftazidime  and levofloxacin were 4.12%  and 3.00% respectively；resistant rate to compound sulfamethoxazole had increased tendency（χ2=5.885, P=0.015）.ConclusionIsolation of B. cepacia in  ICU increased year by year, antimicrobial resistance is serious, management and targeted monitoring of prevention and control of healthcareassociated infection should be strengthened， antimicrobial agents should be chosen according to antimicrobial susceptibility testing results.

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ObjectiveTo investigate cognitive status and influencing factors for hand hygiene(HH) among health care workers(HCWs) , and provide basis for scientific management of HH.MethodsIn April 2013,  HCWs in a general hospital were selected  by randomly sampling method, questionnaires were used to survey the implementation of HH in recent one month and HCWs’ cognition on knowledge about HH.ResultsA total of 750 HCWs were investigated, 652 available questionnaires were collected. The frequency of hand washing and hand disinfection per day among most HCWs were 10-19 times, accounting for 46.62% and 47.85% respectively;  30.52% of HCWs washed their hands for ≥30 seconds each time, 60.58% of HCWs dried hands with paper towel after washing hands, 57.21% of HCWs  abided by  sixstep hand washing method. The overall correct rate of cognition on ten opportunities that requiring HH in clinical practice was 68.68%.The main factors influencing the implementation of HH were as follows: skin irritation of hand sanitizer and hand disinfectant subjectively considered by HCWs(63.34%), inadequate hand washing facilities( 41.10%);  high cost of hand sanitizer ,  hand disinfectant, and dry paper towel (38.96%),et al.ConclusionIn addition  to intensifying education on HH, installing rational HH facilities and improving HH standard are  key points in strengthening HH in general hospital.

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ObjectiveTo realize basic status of occupational exposure among medical postgraduates, and provide theoretical evidence for making occupational precaution measures.MethodsData about occupational exposure among medical postgraduates in a teaching hospital between January 2011 and December 2013 were analyzed retrospectively.ResultsA total of 3 362 medical postgraduates  were monitored, 56 (1.67%) sustained occupational exposure. The most common occupational exposure sites were left hand  thumbs(n=15, 26.79%）, occupational exposure most frequently occurred during operation（n=29，51.79%），a total of 40(71.43%)  occupational exposure occurred during the process of  operation and invasive procedure,all were sharp injuries. 46(82.14%) exposure sources were with bloodbornetransmitted diseases. Surgery students accounted for 66.07%(n=37) of students sustained occupational exposure, exposure rate in master’s candidates was higher than doctoral  candidates(2.31% vs 0.28%，χ2=18.325，P＜0.001）. After timely treatment and preventive medication, none of the students were infected.ConclusionIt is necessary to strengthen the occupational safety education for medical postgraduates, improve precaution awareness, standardize all kinds of procedures,and implement standard precaution; timely and effective treatment after exposure is important for reducing occupational injury among medical postgraduates.

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ObjectiveTo intervene hand hygiene(HH)  of health care workers (HCWs) in an intensive care unit(ICU) of a hospital,  and evaluate HH compliance of  HCWs and influencing factors.Methods37 HCWs from an ICU of a teaching hospital were chosen as studied subjects, HH status before and after intervention was observed and analyzed by direct and indirect methods.ResultsIn the first monitoring stage, HH rate in baseline and postintervention survey stage was significantly different （46.96% vs  63.30%, χ2=7.344，P=0.007); in the second monitoring stage, HH compliance rate increased from 57.85%  to 88.58%. HH compliance rate was positively correlated with consumption of HH product per  bedday（r=0.725,P＜0.001）, but negatively correlated with incidence of healthcareassociated infection(HAI) and case rate of HAI（r=-0.983, -0.990, respectively, both P＜0.001）, HH rate to alcoholbased hand sanitizers was positively correlated with consumption of HH product per bedday （r=0.391, P＜0.001）.ConclusionLongterm monitoring and intervention of HH compliance is necessary, combination of direct observation and indirect assessment of HH product consumption is helpful for effective monitoring and intervention of HH compliance among HCWs.

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目的比较某院2012—2014年医院感染现患率及抗菌药物使用情况，为医院感染管理提供依据。方法采用床旁调查与查阅病历相结合的方法，于2012年10月31日、2013年6月6日、2014年6月13日对某院所有住院患者进行调查，并填写统一的现患率调查表。 结果2012—2014年医院感染现患率为2.74%，例次现患率为2.97%。各年医院感染例次现患率分别为4.12%、2.50%、2.37%，3年间比较差异有统计学意义（χ2=6.373，P=0.041）。医院感染部位居前3位的分别为呼吸道（占57.95%）、皮肤软组织（占19.32%）、泌尿道（占11.36%）；共检出医院感染病原菌84株，以革兰阴性（G-）杆菌为主（55株，占65.48%）。2012—2014年抗菌药物使用率分别为30.23%、29.57%、32.64%；用药目的以治疗为主（590例，占64.69%），治疗使用抗菌药物病原学送检率为58.92%。结论2012—2014年医院感染现患率呈下降趋势，应进一步加强重点部门、重点部位的医院感染监测与防控，督导临床医生合理、规范使用抗菌药物。

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凡不能用其他原因解释的腹泻（稀便≥3次/24 h）,加上粪便中检测出艰难梭菌（Clostridium difficile，CD）及其毒素，或结肠镜和组织学检查证实为假膜性结肠炎均可确诊为CD感染（Clostridium difficile infection，CDI）［1］。CD是引起抗菌药物相关性腹泻最常见的病原体，约占抗菌药物相关性腹泻的10%～30%。近年来，毒力更强的BI／NAPI／027型CD菌株的出现使CDI发病率增加,且疾病程度更加严重［2］。