Surveillance of antibiotic resistance among the bacterial strains isolated from hospitals in Shanghai: results of 2016 / 中国感染与化疗杂志

ABSTRACT

Objective To investigate the resistance profile of clinical bacterial isolates to antibiotics in Shanghai during 2016.Methods Antimicobial susceptibility testing was carried out for the clinical isolates collected from 47 hospitals according to a unified protocol using Kirby-Bauer method or automated systems.The participating hospitals included 28 tertiary hospitals and 19 secondary hospitals across Shanghai.Results were analyzed according to CLSI 2016 breakpoints.Results A total of 122 548 clinical isolates were collected,including 35 522 (29.0％) strains of gram positive cocci and 87 026 (71.0％) strains of gram negative bacilli.Overall,28.9％ of the isolates were from secondary hospitals and 71.1％ from tertiary hospitals.Gram positive and gram negative isolates accounted for 25.8％ and 74.2％ in secondary hospitals,30.3％ and 69.7％ in tertiary hospitals,respectively.The overall prevalence of MRSA in Staphylococcus aureus was 48.7％ and 77.2％ of MRCNS in coagulase-negative Staphylococcus.The average prevalence of MRSA and MRCNS was 55.9％ and 73.3％ in secondary hospitals,45.9％ and 78.6％ in tertiary hospitals.No strains were found resistant to vancomycin in Staphylococcus.About 77.4％ of the 1 111 strains of non-meningitis S.pneumoniae isolated from children were penicillin-susceptible (PSSP),13.2％ were penicillin-intermediate (PISP) and 9.4％ were penicillinresistant (PRSP).The prevalence of PSSP,PISE and PRSP was 97.8％,2.2％,and 0 in secondary hospitals,76.5％,13.7％,and 9.8％ in tertiary hospitals.Of the 285 strains isolated from adults,94.0％,4.2％ and 1.8％ were PSSP,P1SP and PRSP,respectively.The prevalence of PSSP,PISP and PRSP among the isolates from adults was 93.7％,5.3％,and 1.0％ in secondary hospitals,94.2％,3.7％,and 2.1％ in tertiary hospitals.Overall,37 strains of vacomycin-resistant E.feacium (14 from secondary hospitals and 23 from tertiary hospitals) and 25 strains of vacomycin-resistant E.feacalis (all from tertiary hospitals) were identified.PCR and sequencing analysis indicated that most of these resistant strains were vanA type.The overall prevalence of ESBLs-producing srains was 52.2％ in E.coli,30.9％ in Klebsiella pneumoniae and 29.8％ in Proteus mirabilis.Specifically,the corresponding prevalence of such strains was 55.1％,33.6％ and 34.0％ in secondary hospitals,51.0％,29.7％ and 28.0％ in tertiary hospitals,respectively.Enterobacteriaceae strains were still highly susceptible to carbapenem antibiotics.Overall,8.9％ and 9.1％ of the Enterobacteriaceae strains were resistant to imipenem and meropenem,respectively.The figure was 6.6％ and 7.1％ in secondary hospitals,9.9％ and 10.0％ in tertiary hospitals.Extensively drug-resistant strains were identified in A.baumannii,K.pneumoniae,P.aeruginosa,and E.coli,specifically,223,63,10,and 4 strains in secondary hospitals;224,201,22,and 9 strains in tertiary hospitals.Conclusions Antibicotic resistance is still very serious in the common clinical strains,which poses a critical threat to healthcare facilities.This issue should be taken seriously and effective infection control measures must be put in place.