Objective To investigate the distribution and antimicrobial susceptibility of clinical strains ofEnterobacteriaceae isolated from Huashan Hospital in 2014.MethodsEnterobacteriaceae were isolated from January to August 2014. Antimicrobial susceptibility testing was performed by agar dilution method. TheblaKPC gene was screened by PCR and DNA sequencing. Results were analyzed by WHONET 5.6 software.Results A total of 719 strains ofEnterobacteriaceae were collected, of whichKlebsiella spp., andE .coli accounted for 43.8% (315/719) and 30.4% (219/719), respectively. Resistance rates ofKlebsiella spp.,E. coli, andCitrobacter spp., to polymyxin B and polymyxin E were low (<3%). The percentage of theEnterobacter strains resistant to polymyxin B and polymyxin E was 10.9% and 11.1%, respectively. About 47.5% and 44.7% of theSerratia strains were resistant to polymyxin B and polymyxin E, respectively. More than 90% of theMorganella andProteus isolates were resistant to polymyxin B or polymyxin E. The carbapenem-resistantEnterobacteriaceae strains were mainly identiifed inKlebsiella isolates, more than 40% of which were resistant to meropenem and ertapenem, but only 2.9% and 2.6% were resistant to polymyxin B and polymyxin E, respectively. Ertapenem resistance was identified in 27.8% of theCitrobacter isolates and 17.9% of theSerratia isolates. Less than 10% of the otherEnterobacteriaceae strains were resistant to carbapenem. Overall, 20.7% (149/719) of the isolates wereblaKPC positive, mainly inK. pneumoniae (129/315, 41.0%). Seven strains ofSerratia marcescens and 2 strains ofK. Pneumoniae were resistant to both carbapenems and polymyxin.Conclusions The clinical isolates ofKlebsiella, E. coli, Enterobacter andCitrobacter in 2014 were still highly susceptible to polymyxin antibiotics.

Objective To investigate the changing patterns of serum IL-6, IL-10, IL-23 and osteopontin in patients with smear-negative pulmonary tuberculosis before and after treatment and their clinical implication.Methods A total of 43 patients with smear-negative pulmonary tuberculosis and 40 healthy controls were included in this study. Enzyme-linked immunosorbent assay (ELISA) was conducted to measure the levels of serum IL-6, IL-10, IL-23 and osteopontin in healthy individuals and patients before and after anti-tuberculosis treatment for 2, 4 and 6 months.Results The levels of serum IL-6, IL-10, IL-23 and osteopontin in patients with smear-negative pulmonary tuberculosis were signiifcantly higher than those in control group (P<0.05). After treatment for two months, the levels of serum IL-6, IL-10, IL-23 and osteopontin signiifcantly decreased in patients with smear-negative pulmonary tuberculosis (P<0.05). The serum IL-10 and osteopontin were nearly restored to normal levels in patients after four months treatment and there were no signiifcant difference compared with those in control group (P>0.05). The levels of serum IL-6 and IL-23 gradually decreased after treatment, and restored to normal at six months. There was no signiifcant difference compared with those in control group (P>0.05). Conclusions Serum IL-6, IL-10, IL-23 and osteopontin levels in patients with smear-negative pulmonary tuberculosis can be used as sensitive indicators for assessment of tuberculosis disease activity and therapeutic effect of anti-tuberculosis drugs.

Objective To investigate the prevalence, accessory gene regulator (agr) and staphylococcal cassette chromosome mec (SCCmec, only for methicillin resistantS. aureus, MRSA) types of theS. aureus strains carrying toxic shock syndrome toxin-1 (tst) and/or panton-valentine leukocidin (pvl) genes.Methods Nine hundred and sixteen isolates ofS. aureus were collected from seven hospitals in Shanghai and Zhejiang Province and subjected to detection oftst,pvl,mecA andmecC genes by polymerase chain reaction (PCR). Theagr and SCCmec (only for MRSA) types were determined in thetst orpvl gene positive isolates.Results Of the 916 isolates, 208 carriedtst gene (22.7%), 35 harboredpvl gene (3.8%), and 665 weremecA positive (MRSA). No isolate was mecC positive. Out of the 665 MRSA isolates, 198 hosted thetst gene (29.8%). The most commonagr and SCCmec types were agr 2 (97.0%) and SCCmec II (94.4%), respectively. For thepvl gene, only 14 isolates were positive (2.1%). Theagr 1 (85.7%), SCCmecIII (42.9%) and SCCmec IVa (28.6%) were the most commonagr type and SCCmec type. In the 251 methicillin-sensitiveS. aureus (MSSA) isolates, 10 carriedtst gene (4.0%) and 21 carriedpvl gene (8.4%). The prevalence oftst gene in MRSA was higher than that in MSSA, while the prevalence ofpvlgene was just the opposite. However, the prevalence ofpvlgene in MRSA isolates from Zhejiang Province was higher than that in the MRSA isolates from Shanghai (P<0.05).Conclusions The prevalence oftst gene in MRSA is signiifcantly higher than that in MSSA. The prevalence ofpvlgene is low in theS. aureus isolates studied. However, clinicians should pay close attention to these strains due to the implication of PVL toxin in some
severeS. aureus infections.

ObjectiveThe clinical features, bacteria distribution and antibiotic resistance proifle of blood stream infection(BSI) were investigated in the patients with decompensated liver cirrhosis for better management of such infections.MethodsThe clinical data of BSI were collected in the patients with decompensated liver cirrhosis between January, 2012 and December, 2014, and reviewed retrospectively in terms of risk factors, diagnosis and treatment, pathogen distribution and prognosis.ResultsOf the 1 071 patients with decompensated liver cirrhosis and suspected bacterial infection, 154 (14.4%) were diagnosed as BSI evidenced by blood culture. Of these patients, the leukocyte count in the peripheral blood was higher than 10×109/L in only 48 (31.2%) patients; neutrophil proportion>0.75 in 133 patients (86.4%); serum procalcitonin level>0.5 ng/mL in 74 patients (68.5%). A total of 155 bacterial strains were isolated, including 115 strains of gram-negative bacilli and 40 strains of gram-positive cocci. Most patients (68.8%) recovered and 31.2% died or discharged from hospital voluntarily. All these BSI patients had Child-Pugh grade C liver function. Some patients also had other serious systemic diseases or repeated hospitalization.ConclusionThe prevalence of BSI is high in the decompensated liver cirrhosis patients with poor prognosis. Gram-negative bacilli are the major pathogens of such septicemia. Early diagnosis and proper use of antibiotics based on antimicrobial susceptibility testing are important to improve patient outcome.

ObjectiveTo understand the clinical and microbiological characteristics of AIDS-associated bloodstream infection (BSI).MethodsThe clinical and laboratory ifndings of 143 cases of BSI in AIDS patients who were hospitalized during the period from 2013 to 2014 were retrospectively analyzed.ResultsThe prevalence of BSI in AIDS patients was 22.1%. The 143 patients were divided into two groups in terms of fungal or bacterial infection. The incidence of speciifc skin rashes, anemia, hepatosplenomegaly and lymph node enlargement in fungal infection group was higher than those in bacterial infection group (allP<0.05). CD4+ cell count, WBC, neutrophils, RBC, hemoglobin, and platelet count in fungal infection group were lower than those in bacterial infection group, while AST and Cr were the opposite (allP<0.05).Penicillium marneffei(84/143, 58.7%) was the most common pathogen isolated from AIDS-associated BSI, followed byEscherichia coli (10/143, 7.0%),Cryptococcus neoformans (9/143, 6.3%),Klebsiella pneumoniae (7/143, 4.9%),Salmonella (6/143, 4.2%),Candida albicans(3/143, 2.1%), andAeromonas (3/143, 2.1%). Most strains were still susceptible to the commonly used antibiotics.ConclusionsThe prevalence of BSI is high in AIDS patients. Fungal BSI is more likely to have skin rash, anemia, hepatosplenomegaly and lymphadenopathy, hematologic abnormalities, liver and renal function impairment. Fungi, especiallyPenicillium marneffei, are the main pathogen of AIDS-associated BSI. Most strains are susceptible to the commonly used antibiotics.

Objective To examine the distribution of bacterial species and antimicrobial susceptibility profile of pathogens in febrile neutropenic patients.Methods A total of 355 bacterial strains were isolated from febrile neutropenic patients in Shanghai General Hospital from January 2005 to December 2012. Antimicrobial susceptibility testing was done by Kirby-Bauer method. The susceptibility testing results were analyzed according to CLSI 2014 breakpoints.Results Gram-negative bacteria accounted for 70.4% of the 355 isolates, while gram-positive organisms accounted for 29.6%. The most common bacterial species werePseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Stenotrophomonas maltophiliaand Staphylococcus haemolyticus. Non-fermentative bacteria accounted for 53.2% of all the gram-negative bacterial isolates. All theEnterococcus and
Staphylococcus isolates were susceptible to linezolid, vancomycin and teicoplanin. All theStaphylococcus strains were resistant to methicillin.P. aeruginosa isolates were relatively more susceptible to cefoperazone-sulbactam, piperacillin-tazobactam and cefepime (>70%) than imipenem (40.8%) and meropenem (59.2%). All theK. pneumoniae isolates were susceptible to imipenem and meropenem and more than 70% of the isolates were susceptible to cefoperazone-sulbactam, amikacin. More than 80% of theA. baumannii isolates were susceptible to carbapenems, cefoperazone-sulbactam, amikacin, ciprolfoxacin and aminoglycosides. All the E. coli isolates were susceptible to carbapenems and more than 70% were susceptible to cefoperazone-sulbactam and ceftazidime. More than 90% of theS. maltophilia strains were sensitive to levolfoxacin, minocycline, cefoperazone-sulbactam and trimethoprim-sulfamethoxazole.Conclusions Our data suggest that gram-negative bacteria, especiallyEnterobacteriaceae and non-fermentative bacteria, are still the primary pathogens in febrile neutropenic patients. Antimicrobial resistant strains are prevalent. Such data of bacterial species and antimicrobial susceptibility proifle of pathogens in febrile neutropenic patients are useful for empirical antimicrobial therapy of such infections.

Objective To investigate the distribution and antibiotic resistance of clinical isolates in People’s Hospital of Qingyang during 2014 to provide evidence for rational antimicrobial therapy.Methods Bacterial strains were isolated and identified by routine methods and tested by disk diffusion method and E-test for antimicrobial susceptibility. The data were analyzed according to CLSI breakpoints using WHONET 5.6 software.Results Of the 2 121 nonduplicate strains isolated from January through December 2014, 1 565 (73.8%) were gram-negative and 556 (26.2%) were gram-positive strains. The top ifve pathogens wereE. coli, K. pneumoniae, A. baumannii, S. aureusand P. aeruginosa. The prevalence of methicillin-resistantStaphylococcus aureus (MRSA) and methicillin-resistant coagulase negativeStaphylococcus (MRCNS) was 44.6% and 15.4%, respectively.E. coli was the most common gram-negative bacterial species, whileS. aureus was the most common gram-positive bacteria species. Gram-positive bacteria were still highly susceptible to vancomycin, and gram-negative bacteria (such as Enterobacteriaceae) were still highly susceptible to carbapenems.ConclusionsE. coli is the most prevalent pathogen isolated from inpatients in this hospital during 2014. The prevalence of ESBLs-producing strains is the highest inE. coli isolates. The pathogenic bacteria in this hospital showed increasing resistance to a variety of antibacterial agents. Surveillance of antibiotic resistance and effective control measures are necessary to control the growing antimicrobial resistance.

Objective To examine the distribution and antibiotic resistance proifle of the bacterial isolates from lower respiratory tract of hospitalized patients for better empirical therapy.Methods A total of 3 155 lower respiratory tract specimens were collected from Respiratory Department of the First Afifliated Hospital of Chongqing Medical University in 2013 to identify bacterial pathogens for susceptibility testing. The results were compared with the data of 2011 and 2012.Results The top three bacterial species from lower respiratory tract in the period from 2011 to 2013 wereA. baumannii,P. aeruginosa, andK. pneumoniae. The prevalence ofS. aureusincreased, while the prevalence ofS. maltophilia andS. pneumoniae was still low.A. baumannii isolates were highly resistant to antibiotics. Not more than 40% of these strains were susceptible to the antimicrobial agents except minocycline, which was active against more than 60% of the ICU and non-ICU strains. More than 70% of theP. aeruginosa strains from non-ICU were susceptible to cefepime, meropenem, imipenem, levofloxacin, and ciprofloxacin in the three years, 50%-70% of the strains from ICU were susceptible to the antimicrobial agents tested. Carbapenem-resistantA. baumannii andP. aeruginosa strains were identiifed.S. maltophilia strains were relatively susceptible to minocycline and levolfoxacin. All the S. aureus isolates were susceptible to vancomycin, linezolid, and tigecycline. The prevalence of MRSA increased year by
year. More than 80% of theK. pneumoniae andE. coli strains were susceptible to imipenem, piperacillin-tazobactam, and cefepime. ESBLs-producingK. pneumoniae was identified. More than 85% of theH. influenzae strains were susceptible to meropenem, ceftazidime, cefuroxime, ciprolfoxacin, levolfoxacin, and amoxicillin-clavulanate potassium. All theS. pneumoniae isolates were susceptible to vancomycin, and 80%-96% of these strains were susceptible to levofloxacin and penicillin.ConclusionsA. baumannii,P. aeruginosa, andK. pneumoniae are the top three bacterial species isolated from lower respiratory tract. Carbapenem-resistantA. baumannii,P. aeruginosa and ESBLs-producingK. pneumoniaeare emerging. The prevalence of MRSA is increasing year by year, which poses a challenge to antimicrobial therapy. It is urgent to contain and control the growing antibiotic resistance.

Objective To examine the prevalence ofHelicobacter pylori in Shanghai and relevant risk factors, evaluate the resistance proifle ofH. pylori isolates to antibiotics used in ifrst-line therapy in two hospitals in Shanghai.MethodsH. pylori were isolated from the biopsy samples of gastric mucosa collected from September 2013 to January 2015. Antimicrobial susceptibility test was performed by E-test method for 131H. pylori strains to 4 antibiotics, clarithromycin, metronidazole, amoxicillin and tetracycline. Results A total of 955 patients receiving gastroscopy were enrolled. And 248 (26.0%)H. pylori strains were isolated from the biopsy samples of gastric mucosa. Overall, 14.5%, 64.1%, 0 and 0.8% of the strains were resistant to clarithromycin, metronidazole, amoxicillin and tetracycline, respectively. Resistance to two drugs was found in 10.7%(14/131) of the strains, and majority (92.8%, 13/14) of which were resistant to clarithromycin and metronidazole.Conclusions The prevalence ofH. pylori in gastric mucosa is rather lower compared with the data reported previously. It is associated with the sex, age and clinical outcome of patients, however, antibiotic resistance profile is not related to these factors.H. pylori eradication therapy should be individualized according to the results of susceptibility test in Shanghai.

Objective To investigate the antimicrobial resistance proifle in the clinical bacterial strains isolated from Peking Union Medical College Hospital during 2014.Methods A total of 8 295 nonduplicate clinical isolates were collected. Disc diffusion test (Kirby-Bauer method) and automated systems were employed to study the antimicrobial susceptibility. The data were analyzed by using WHONET 5.6 software according to CLSI 2014 breakpoints.Results Of the 8 295 isolates, 67.4% were gram-negative, and 32.6% were gram-positive. The top 10 most frequently isolated bacteria were:E. coli(18.1%),P. aeruginosa (10.8%),K. pneumoniae (10.2%),S. aureus (9.8%),
A. baumannii(9.2%),E. faecalis (6.3%),E. faecium (4.1%), coagulase-negativeStaphylococcus (4.1%),E. cloacae (3.1%) andS. maltophilia (2.9%). Methicillin resistant strains inS. aureus (MRSA) and coagulase negativeStaphylococcus (MRCNS) accounted for average of 28.4% and 66.5%, respectively. The resistance rates of MR strains to β-lactams and other antimicrobial agents were much higher than those MS strains. Overall, 81.3% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 81.1% of MRCNS strains were susceptible to rifampin. No staphylococcal strains were resistant to vancomycin, teicoplanin or linezolid. The resistance rate ofE. faecalis strains to most of the drugs tested (except chloramphenicol) was much lower than those ofE. faecium. Several strains of bothE. faecium andE. faecalis were found resistant to vancomycin and teicoplanin, which were Van-A and Van-B types based on their phenotype. No linezolid resistant enterococcal strains were found. Data showed that 90.8% ofβ-hemolyticStreptococcus strains were susceptible to penicillin. ESBLs-producing strains accounted for 54.2%, 31.0% and 28.9% inE. coli,Klebsiella spp (K. pneumoniae andK. oxytoca) andP. mirabilis, respectively.Enterobacteriaceae isolates were still highly susceptible to carbapenems. Overall, no more than 3.3% of these strains were resistant to carbapenems. A few extensively drug-resistant strains ofK. pneumoniae (1.3%, 11/842) were identiifed. The resistance rates ofP. aeruginosa to imipenem and meropenem were 17.5% and 11.8%, respectively.P. aeruginosa isolates showed the lowest resistance rate (5.9%) to amikacin. And 69.0% and 67.4% ofA. baumanniiisolates were resistant to imipenem and meropenem.A. baumannii isolates showed the lowest resistance rates to cefoperazone-sulbactam and minocycline (47.8% and 28.7%), respectively. The prevalence of extensively drug-resistant strains was 32.3% inA. baumannii and 1.8% inP. aeruginosa. The prevalence of β-lactamase inH. inlfuenzae was 33.7%. More than 93.0% ofS. pneumoniae strains were resistant to erythromycin and clindamycin.Conelusions Bacterial resistance is still increasing in this hospital, especially carbapenem resistantEnterobacteriaceae. It is necessary to take effective hospital infection control measures and use antibiotics rationally.