Non-tuberculous mycobacteria ( NTM) are organisms ubiquitously existing in the environment, which have been considered as contamination or colonization bacteria .In recent years, more and more evidences suggest that NTM can cause human diseases , resulting in nosocomial infection, even outbreaks.The aim of this article intends to introduce the epidemiology and prevention of NTM infection .

Objective　 To investigate the changing spectrum and antibiotic resistance of the pathogenic bacteria isolated from general surgical infections.　Methods　 The relevant bacterial materials from 557 patients with general surgical infection from June 1993 to July 1997 were investigated.　Results　 1 045 strains in 38 species of gram-negative bacteria and 418 strains (8 species) of gram-positive bacteria were isolated with a negative over positive rate of 71.4% to 28.6%. For gram-negatives, E coli was the most common, and enterobactor cloacae ranking the third was on a dramatic increase from isolations. Staphylococcus aureus and staphylococcus epidemidis were the most common gram-positive species followed by enterococcus faecalis. Enterobactor cloacae and enterococcus faecalis are multi-antibiotic resistant bacteria. The result of drug susceptibility test showed that gram-negative bacteria were sensitive to fluoroqinolones or third-generation cephalosporins while gram-positive bacteria were sensitive to vancomycin and rifampicin.　 Conclusion　 This study showed that the rational application of antibiotics is very important to suppress the spectrum changing and antibiotic resistance of the bacteria.

Objective To explore the risk factors of septicemia in hospitals. Methods A retrospective control study of cases was conducted, using SPSS software to conduct single factor and Iogistic regression analysis so as to screen possible risk ractors. Results Differences of 14 factors were shown to be statistically significant in the analysis of single factors. Further Iogistic regreasion analysis of the 14 factors indicate that the following are independent risk factors of septicemia in hospitals: basic diseases(OR = 5.3), tumor chemotherapy(OR=15.9), albumin＜30g/L(0R=5.9), vascular catheterization ＞ 2 days(OR= 5.2), operation time＞ 4 hours(OR= 4.9), continuous use of antibiotics(OR=1.1), and simultaneous use of more than 2 kinds of antibiotics(OR= 9.0).Conclusion Septicemia in hospitals results from the synergistic effect of a variety of factors. The possible risk factors that have been screened need to be further confirmed through perspective studies and clinical trials.

Objective To investigate the physiological state of L. pneumophila in biofilm. Methods Genes previously identified as good markers for the transmissive and replicative phases of the L. pneumophila life cycle during growth in Acanthamoeba castellanii were examined for their expression fold change in the sessile cells as compared to planktonic cells using real-time RT PCR. Results Mature L. pneumophila biofilms were formed at 37t in 75 cm2 cell culture treated flasks for 18 days. The ratio of gene (mip, flaA and fliA) expression in post-exponential cells compared to exponential cells is 0. 53, 4. 45 and 3. 67. The exponential phase cultures display replicative traits and post-exponential bacteria express transmissive factors. The ratio of gene (mip, flaA and fliA) expression in sessile cells compared to exponential cells is 4.42, 5.24 and 16.21, while the sessile cells compared to exponential cells is 8.39, 1. 18 and 4. 43, respectively. Conclusion The violence gene expression of L pneumophila in biofilm is unique.

OBJECTIVE To compare the difference of Pseudomonas aeruginosa(PAE) biofilms formation in different conditions including incubated time,temperature,attaching materials,and flowing speed.METHODS PAE biofilms were established in a chemostat-coupled MRD and detected with the method of viable bacteria counting.The number of CFU/disc was measured in different culture time(8h,24h or 72h),different temperature(23℃ or 37℃),different adherent materials(glass or silicone),different flow velocities(30ml/h or 90ml/h) and different culture media(M63 medium,M-H croth or LB broth).RESULTS Keeping the other conditions invariable,the log10CFU/disc of viable bacteria in 8h,24h or 72h biofilms were 4.01?0.26,4.59?0.49 or 5.20?0.47,respectively(P

Objective To describe the profile of patients with infective endocarditis (IE) and assess prognostic factors of IE.Methods Clinical and etiology data of 218 patients with IE were collected retrospectively from January 2011 to January 2013.The distribution and antimicrobial susceptibilities of pathogens causing IE were evaluated.Prognostic factors associated with IE were determined by univariate and multivariate regression analysis.Results There were 148 men and 70 women with age of (46.0 ± 14.6)years.Ninety-five (43.6％) of them had heart diseases,including 72 cases (33.0％) of congenital heart disease and 23 cases (10.6％) of chronic rheumatic heart disease.Vegetations were detected by echocardiography in 171 (78.4％) patients.Microorganisms causing IE were identified in 84 cases (38.5％) cases.Streptococcus viridans was the dominant pathogen,accoumed for 63.1％ of all the pathogens,followed by Staphylococcus (13.1％) and Enterococcus (4.8％).Totally 7/11 Streptococcus viridans was susceptible to penicillin,while 100％ susceptible to the third and fourth generation cephalosporins,vancomycin and linezolid.One hundred and eighty cases underwent operations.The in-hospital mortality rate of IE was 3.2％.In univariate regression,health care-associated infection,prosthetic valve,anemia and chest symptoms (distress or pain) were related to the increased risk of mortality in patients with IE,while surgery appeared to be a protective factor.In the logistic regression model,the variables significantly associated with IE prognosis were health care-associated infection (OR =17.03,95％ CI 1.76-164.75,P =0.014) and anemia (Hb ＜ 90 g/L) (OR =13.47,95％ CI 2.46-73.60,P =0.003) and surgery treatment (OR =0.17,95％ CI 0.03-0.97,P =0.047).Conclusions Although Streptococcus viridans is the most common pathogen causing IE,the pathogens of IE become versatile.The antibacterial activity of penicillin against Streptococcus viridans is low.Health care-associated infection and anemia are risk factors of IE prognosis,while surgery treatment is a protective factor of severe IE.

Objective To explore the incidences of ventilator-associated pneumonia (VAP)in intensive care units (ICUs)in China.Methods From October 2013 to September 2014,46 hospitals in 12 provinces and cities were se-lected to participate in the study,all patients admitted to ICUs were included,the incidences of VAP were surveyed and compared with data from the U.S.National Healthcare Safety Network (NHSN).Results A total of 17 358 patients were surveyed,the total patient-days were 176 096 d,the total catheter-days were 91 448 d,813 patients developed VAP,the incidence of VAP was 8.89/1 000 catheter-days,VAP mainly occurred in general ICUs (76.74%);the incidences of VAP were varied with patients in different types of ICUs,ranging from 4.50/1 000 catheter-days to 32.79/ 1 000 catheter-days.Conclusion The incidence of VAP in patients in ICUs at 46 hospitals in China is significantly higher than that reported by NHSN,even higher than the P90 .

Objective The purpose of this study was to compare and develop the method for identification of Non-tuberculous Mycobacteria (NTM) using matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS),and evaluate the feasibility,accuracy and repeatability of MALDI-TOF MS to discriminate NTM.Methods Fifteen clinical strains were collected from January to March in 2012 and 68 environmental strains were retrospectively collected from 2011 to 2012.A protocol for sample pre-treatment and protein extraction was developed and utilized it to identify clinical and environmental isolates.The results from 16 s rRNA sequencing were served as control.Results Method A was more effective in protein extraction.Although all the three methods got the same species result,a total of 83 strains belonging to 10 distinct species grown in Middle brook 7H10 media were analyzed.All members of the NTM were identified accurately at the genus level and 80.7％ (67/83) of strains could be identified at the species level.Six strains were identified at the complex level.81.9％ (68/83) of NTM got high spectral scores.The identification of cultured colony could be completed in 1.5 hours.And it had good reproducibility.Conclusion MALDI-TOF MS can be used as a rapid and accurate method for identification of Mycobacteria in clinical microbiology laboratories,implying its good application prospects.

Objective To investigate the prognosis and related factors of community acquired pneumonia (CAP). Methods From August 2003 to March 2009, 689 CAP cases from 37 hospitals of 23 cities in China were enrolled. The onset information and clinical outcomes in one month of onset were recorded. Pearson Chi-square test and Logistic regression test were performed using the SPSS 12.0 software to identify prognosis-related factors. Results Among 689 patients there were 396 male and 293 female. The median age was (53 19) years old, 247 patients (35.8%) were≥65 years old. Forty four patients died with a fatality rate of 6.4%. Univariate analysis identified 19 risk factors, they were age≥65 years old, smoking, aspiration, use of antimicrobial agents in 3 months, use of immunodepressant in 2 months, heart failure, chronic renal failure, chronic liver disease, eerebrovascular disease, diabetes, emaciation, altered mental status, respiratory rate > 28/min, pulse > 100/min, lower diastolic blood pressure, neutrophil ratio > 0.9, ALT >40 U/L, elevated blood urea nitrogen level and PORT classification ≥Ⅳ. By multivariate analysis, use of antimicrobial agents in 3 months, respiratory rate > 28/min, pulse > 100/min and PORT classifications≥Ⅳ were identified as the independent risk factors for mortality. Conclusions The general fatality rate of CAP is low in China. Use of antimicrobial agents in 3 months, respiratory rate > 28/min, pulse > 100/min and PORT classifications≥Ⅳ are independent risk factors for mortality.

The diagnosis and treatment of invasive fungal infections has been attracting more and more attention along with the increase incidence in the current clinical practice.We hereby work out this paper to elaborate some key issues,coveting the history and methodology of anti-fungal susceptibility testing, the MIC recognition of yeast fungus and mycelial fungus,breakpoint interpretation,and finally the guidance for clinical practice.To better undemtand susceptibility test results and improve the guality of susceptibility tests in this review,we chosed several most-often used anti-fungal drugs and explained their effect activity.