To help the clinical microbiology laboratories understanding the standards of antimicrobial susceptibility testing (AST) from Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) ; discuss when to perform AST,how to confirm unusual or inconsistent results and adopt the suitable AST method,how to interpret the information of continuous monitoring development of resistance and testing of repeat isolates,how the drug-resistance mechanism influence the report and treatment.This will provide accurate and timely AST results for clinicians.

OBJECTIVE To investigate the ?-lactamases producing rate in Haemophilus influenzae(HIN) and the antibiotics sensitivity,to guide the treatment of Haemophilus species infection.METHODS The strains from respiratory tract samples,were isolated and cultivated in chocolate cultures 2006 to 2007.Drug sensitivity test and beta-lactam enzyme test of Haemophilus species were taken.The results were analyzed by software SPSS11.5.RESULTS Totally 195 isolates of HIN were isolated 32 produced ?-lactamases(16.4%).The sensitivity of H.influenzae to cefuroxime,cefotaxime and ampicillin/sulbactam was 90.8%,93.8% and 95.4%,respectively.CONCLUSIONS Cefotaxime,ampicillin/sulbactam and cefuroxime are the most effective antibiotics for H.influenzae infection.

OBJECTIVE To investigate the current status about fungal infections in hospital and to provide the evidence to clinical treatment by identification,and susceptibility test for 62 strains of fungal infection in target population.METHODS The positive sample of blood culture was detected by Bio-Merieux Bact/Alert 3D fully automated microbial detect system,and the fungus identified by Bio-Merieux API 20C Aux yeast system,VITEK identification system,or YBC identification card.The susceptibility test perform by ATB Fungus 2 INT tip.The fungal strains were cultured with Sabouraud medium.RESULTS Among the 62 fungal strains,61 were Candida which accounted for 88.7%,from them C.albicans was predominan,accounted for 35.5%.Susceptibility rate to fluconazole,amphotericin B,itraconazole and flucytosine was 91.0%,100.0%,91.0%,and 100.0%.The distribution of fungi was higher in ICU accounted for 50.0% than in other wards.CONCLUSIONS The rate of the Candida especially C.albicans infection is increasing in Beijing Hospital.The result of susceptibility test showed that the fungi are good susceptibe to antifungal drugs.Highly resistant strain is rare,therefore,the clinics should choose the appropriate antifungal agents and minimize the incidents of resistance of fungal infections according to the culture and in vitro susceptibility of fungus.

Objective To evaluate the reliability of using imipenem,meropenem,cefoperazonesulbactam,piperacillin-tazobactam in the treatment of hospital-acquired Gram-negative bacterial infections with Monte Carlo simulation(MCS).Methods The MIC of the four agents collected from hospital-acquired infections were detected in accordance with broth dilution method of Clinical and Laboratory Standard Institute (CLSI).MCS were conducted with MICs and the pharmacokinetics parameters of the four agents based on conventional dose regimens.The cumulative fraction of response (CFR) of time over MIC target attainment in different dosing regimen were generated.Results A total of 2 541 strains,including 2 093 strains of Enterobacteriaceae and 448 strains of glucose non-fermentative bacilli were collected.The MIC90 of imipenem and meropenem against Enterobacteriaceae were less than 1 mg/L in general,whereas MICg0 of two agents with β-1actamase inhibitors was around 64 mg/L.As to glucose non-fermenting bacteria,MICs of all the four agents were very high,especially to Acinetobacter baumannii,which indicated MIC50 more than 32 mg/L.MCS revealed that carbapenems had significantly higher CFR than those with β-1actamase inhibitors.Imipenem and meropenem (1 g,q8 h) obtained CFRs of 74.69％ and 81.42％,respectively.The CFR of cefoperazone-sulbactam (2 g,q8 h) and piperacillin-tazobactam (4 g,q6 h) (both excluding β-1actamase inhibitors) were just 49.59％ and 27.66％ respectively,which increased after excluding A.baumannii in piperacillin-tazobactam.Conclusions The conventional dose regimens of imipenem and meropenem are reliable for the empiric therapy of Gram-negative hospital-acquired bacterial infections.Piperacillin-tazobactam is suggested to use with higher doses or prolonged infusion time to satisfy the time of drug concentration exceeded the MIC (T ＞ MIC) requirement.More clinical studies of cefoperazone-sulbactam should be conducted to optimize its regimen and guarantee its efficacy.

Objective　To select suitable media for increasing isolation rate of haemophilus.Methods　Haemophilus was inoculated on seven types of media.The average growth index(GI) of Haemophilus was calculated and Haemophilus was isolated from 325 specimens of the respiratory tract and its isolation rate was compared with that media of brchoc and brchoc-V agare.Results　The GI of media with 2% fresh yeast infusion and 50% of meat infusion was higher than that of those with no yeast and meat infusion.The GI of Haemophilus on BRchoc was higher than that of the BSchoc(P<0.001).The isolation rate of Haemophilus from 325 respiratory tract specimens on BRchoc-V was 77.2%,which was significantly higher than that on the medium BRchoc (32.0%).Conclusions　BRchoc-V is a better medium for isolation of Haemophilus.This medium is effective to improve the isolation rate of Haemophilus.

OBJECTIVE To compare the BacT/Alert FN with Botai SN anaerobic blood culture bottles for detection of commonly encountered anaerobes.METHODS Using these two types of anaerobic bottles to culture 5 commonly encountered anaerobes in automatic blood culturing system and BacT/Alert system,and then to analyze the results.RESULTS There were all 32 anaerobic bottles reported positive results by BacT/Alert FN bottles,and only 8 positive bottles were reported by Botai SN bottles.CONCLUSIONS The performance of the BacT/Alert FN is much better than Botai SN anaerobic blood culturing bottle when it is used to detect commonly encountered anaerobes.

OBJECTIVE To investigate the variation of in vitro activity,the ?-lactamases,type diversity and the homology of multiple resistances in Acinetobacter isolated.METHODS The multiple resistant Acinetobacter were selected to detect susceptibility test by K-B antimicrobial agents.The resistant rates were analyzed by WHONET 5.4,the isolates ?-lactamases phenotype was detected by three-dimensional test,genomic types were measured by PFGE.The ?-lactamases genotype was determined by PCR assay with specific-primer,and DNA sequencing was also used to analyze resistance-related gene.RESULTS Twenty-eight of 45 strains were OXA producing strains(68.3%),10 strains were IMP producing strains(24.4%),13 strains were TEM producing strains(31.7%),18 strains were CTX-M producing strains(43.9%),6 strains were PER producing strains(14.6%),and 7 strains were AmpC producing strains(17.1%).None produced SHV ?-lactamases.Twenty-four strains were produced 2 or more than 2 kinds of ?-lactamases.CONCLUSIONS The multiple resistance of Acinetobacter can produce kinds of ?-lactamases,but producing ?-lactamases are not the only one mechanism.

Objective To compare the isolation rate of Ureaplasma urealyticum(Uu), Mycoplasma hominis(Mh) and Chlamydia trachomatis(CT), and to analyze the resistance of Mh and Uu to 6 kinds of antibiotics. Methods CT in genitourinary tract of 1 059 NGU patients was detected by kit of VIDAS. Uu and Mh in genitourinary tract was detected by kit of IST. Results From 1 059 tested samples, the total positive percentage for Mycoplasma and Chlamydia was 36.3% and 5.6% respectively, 14.8% and 3.7% for Mycoplasma and Chlamydia from male samples, 52.6% and 7.2% for Mycoplasma and Chlamydia from female samples. The colony counting result showed that the number of female samples with colonies more than 104 cfu/ml was greater than that of male samples, 73.2% versus 60.3% for Uu and 30.5% versus 25% for Mh. The sensitivity of Mycoplasma to antimicrobial agents was as follows from high to low: Pristinamycine, Doxycycline, Josamycin, Tetracycline, Ofloxacin, Erythromycin. Conclusions The isolation of Mycoplasma was more than that of Chlamydia from patients with genitourinary tract infection.Resistance monitoring of Mycoplasma periodically played an important role in clinical drug treatment.

Objectives To evaluate mini/VITAL and BacT/Alert, two fully automated blood culture systems. Methods Standard mini/VITAL AER and ANA bottles (bioM′erieux, Marcy 1′Etoile, France) and BacT/Alert FAN aerobic and FAN anerobic bottles (organon Netherlands) were used. The bottles were analysed over a period of 7 days. A total of 600 samples of blood, 108 samples of body fluid, and 100 strains of imitation were detected by mini/VITAL and BacT/Alert parallelly. The bottles of flagged positive were smeared and Gram stained before being examined under a microscope. Subcultures were performed in parallel on fresh blood agar and chocolate agar incubated in microaerophilic Conditions with 5% CO 2. All the bottles flagged negative were examined in the same conditions as the positive bottles. Results mini/VITAL: The positive rate for aerobic and anaerobic blood cultures was 10% and 5% respectively, for aerobic body fluid culture was 26 9%. No contaminants were detected. 0.5% false positive and 0.8% false negative were detected. 90% of positive sample were detected in 48 h. The shortest time of report of positive bottles was 1.5 h for blood culture. BacT/Alert: The rate of positive of aerobic and anaerobic blood culture was 9.8% and 5% respectively. The positive rate of body fluid culturs was 26.9%. There were used 3 bottles contaminated. The false positive and false negative rate were 0.5% and 0 98% respective. 95.5% of positive bottles were detected in 48 h. The shortest time of flagged positive was 2.5 h. Conclusion mini/VITAL and BacT/Alert were accurate automated blood culture systems for the detection of bacteremia. There was no significant difference on the speed of detection between BacT/Alert FAN bottles and mini/VITAL standard bottles.

Objective To evaluate the effect and feasibility of using estrogen cream for the prevention and treatment of recurrent urinary tract infection (UTI) in postmenopausal women Methods Forty five postmenopausal women with a history of recurrent UTI were divided into two groups (group premarin and group antibiotic) Participants were assigned to apply intravaginal premarin cream (group premarin, n =30) or oral antibiotic (group antibiotic, n =15) for 3 months respectively Urine routine test, midstream urine and vaginal cultures, vaginal health score (VHS), vaginal cell maturation value (MV), endometrial thickness and blood estrogen level were obtained before and after the study Results The incidence of UTI in the group premarin was significantly reduced as compared with that in the group antibiotic (2/27 vs 12/15, P