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Objective:To investigate the pathogen distribution and antimicrobial resistance among lower respiratory tract infections in patients with hematological malignancies.Methods:Sputum samples were collected from 967 patients with hematological malignancies and lower respiratory tract infections in Department of Hematology,the Second Hospital of Shanxi Medical University from January 2017 to July 2020. The pathogens and drug sensitivity reports were carried out by automatic bacterial identification instruments. WHONET 5.6 and SPSS 20.0 softwares were used for statistical analysis.Results:A total of 961 strains of pathogens were isolated, 516 (53.7%) pathogens were Gram-negative bacteria, mainly 118 strains of Klebsiella pneumonia (12.3%), 68 strains of Pseudomonas aeruginosa (7.1%), 67 strains of Acinetobacter baumannii (7.0%),52 strains of Stenotrophomonas maltophilia (5.4%), 43 strains of Escherichia coli (4.5%), and 42 strains of Enterbacter cloacae (4.4%). There were 171 (17.8%) strains of Gram-positive bacteria and 274 (28.5%) fungi. The drug resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem were 22.1%-31.3%. Stenotrophomonas maltophilia was sensitive to levofloxacin, compound sulfamethoxazole and minocycline. The antimicrobial resistance rates of these three enterobacteria to carbapenems, cefoperazone/sulbactam, piperacillin/tazobactam were low (<10%). The resistant Gram-positive bacteria to ticoplanin, vancomycin and linazolamide were not detected.Conclusion:The major pathogens related to lower respiratory tract infections in patients with hematological malignancies are gram-negative bacteria in our centre. Different pathogens appear different characteristics of antimicrobial resistance.
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This study aimed to investigate antimicrobial susceptibility of hospital acquired Burkholderia cepacia infection in Shanxi [China] during August 2009 and December 2012. To characterize an emerging nocosomial infection. The medical records of 112 patients that were tested positive for B. cepacia were retrospectively analyzed. The K-B disk diffusion method was used to determine the drug susceptibility of the isolated strains. A hundred and fifty strains of B. cepacia were isolated from 112 patients. The sensitivity rates of B. cepacia to meropenem, imipenem, cotrimoxazole, minocycline and ceftazidime were 65.7%, 14.3%, 76.0%, 68.1% and 74.1%, respectively. All patients suffered from more than two underlying diseases, 89 [79.5%] from another bacterial infection and 92 [82.1%] with indwelling catheter. All patients were given antibiotics, including 62 patients that received carbapenem antibiotics. The average duration of hospitalization before detection of B. cepacia was 31+/-24 days, after which 65 patients [58.0%] improved, 22 [19.0%] died, 8 [7.1%] quit the therapy, and 17 [15.2%] were discharged after full recovery. The prevalence of hospital acquired B. cepacia infection and drug-resistance in the hospital is reported and risk factor exploration requires further study
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Objective To characterize 16S rRNA methylase encoding genes associated with aminoglycoaides resistance, gene cassettes of class Ⅰ integrons of the multidrug-resistant Acinetobctcter spp. The sixty one Acinetobacter isolates were collected at the Second Hospital of Shanxi Medical Uni versity from July, 2007 to May, 2008. Methods Species identification was confirmed by sequence analysis of the blaOXA-51-like gene and 16S-23S rRNA gene space-region. Antimierobial susceptibility tests were performed by agar dilution method. 16S rRNA methylaae encoding genes and gene cassettes associated with integrons were amplified by PCR method. Results Among the sixty one strains, there were fifty five of Acinetobacter baumannii, three genospecies 3TU, one 13TU, one Aeinetobaeter ealcoacetieus, and one Aeinetobaeter haemolytieus. Forty eight isolates showed high-level resistance to three aminoglyeosides, including amikaein, tobramyein and gentamicin. The armA gene was found in 47 isolates and all isolates were negative for rmtA, rmtB, rmtC and rmtD genes. The Intl gene was found in 27 isolates. The gene cassettes contained arr-3, accA4,ctacCI ,catB8, aadA1 or dfrA12 genes. According to the PFGE DNA patterns, 5 distinct clones of armA-pasitive strains were identified. Clone A and Clone B were the dominant clones, widely distributed among different divisions. Condnsions 16S rRNA methylase encoding gene (armA) distributed widely in muhidrug-resistant Acinetobacter spp. The armA gene is not located in class Ⅰintegron. The class Ⅰ integron carries multiple resistant genes associated with aminoglycosides and chloramphenieol resistance.PFGE analysis suggests that armA-pesitive strains are widely spread in our hospitaL Effective infection control measure should be conducted in order to control the outbreak of resistant bacteria.