Distribution and drug resistance of pathogens causing nosocomial infection in burn patients / 第二军医大学学报

ABSTRACT

[Abstract] Objective To investigate the pathogen distribution and drug susceptibility profile of isolates from nosocomial infections in burn patients, so as to provide the reference for clinical diagnosis and treatment. Methods A retrospective analysis was carried out for the pathogens isolated from 534 patients in Changhai Hospital of Naval Medical University (Second Military Medical University) during the period from Jan. 2015 to Dec. 2017. The bacteria were identified by VITEK 2 Compact automatic microbiological analyzer or Microflex matrix-assisted laser time-of-flight mass spectrometer. The drug sensitivity was tested by VITEK 2 Compact automatic microbiological analyzer. Results A total of 1 219 strains were isolated, including 877 strains (71.9%) of Gram-negative specimens and 342 strains (28.1%) of Gram-positive pathogens. The top four Gram-negative bacteria were Klebsiella pneumoniae (203 strains, 16.7%), Pseudomonas aeruginosa (183 strains, 15.0%), Acinetobacter baumannii (176 strains, 14.4%) and Escherichia coli (101 strains, 8.3%). The top three Gram-positive bacteria were Staphylococcus aureus (136 strains, 11.2%), Enterococcus faecium (72 strains, 5.9%) and Enterococcus faecalis (60 strains, 4.9%). The pathogens were mainly isolated from wound secretions (577 strains, 47.3%), sputum/bronchoalveolar lavage fluid (341 strains, 28.0%) and urine (147 strains, 12.1%). And 93.5% (319/341) of respiratory pathogens were Gram-negative. Two or more pathogens were isolated from 58.2% (311/534) of the patients. On the top list of Gram-negative pathogens, Klebsiella pneumoniae was observed with a tendency of multi-drug resistance and was resistant to several antibiotics. The drug resistance of Pseudomonas aeruginosa could not be ignored, with a 35.5 % resistance rate for carbapenems. The resistance rate of Acinetobacter baumannii to carbapenems could reach as high as 93.2%, with resistance rate 80.0% to most other antimicrobial drugs. The prevalence of methicillin-resistant Staphylococcus aureus in Gram-positive bacteria was 69.1% (94/136). The resistance rate of Enterococcus spp. to antibiotics was 38.9%-66.3%. No Gram-positive pathogens were observed resistant to vancomycin, tigecycline or linezolid. Conclusion The pathogenic isolates causing nosocomial infection in burn patients are multi-bacterium, Klebsiella pneumoniae shows a tendency of multidrug resistance, and Gram-positive pathogens are sensitive to vancomycin, tigecycline and linezolid.