Study on antibiotic resistance and resistance genes of methicillin-resistant Staphylococcus aureus in children
10.3760/cma.j.issn.1000-6680.2013.11.001
- VernacularTitle:儿童耐甲氧西林金黄色葡萄球菌的耐药性和耐药基因研究
- Author:
Xia WU
;
Chuanqing WANG
;
Xiufeng YAN
;
Aimin WANG
;
Leiyan HE
;
Zuhuang MI
;
Hui YU
- Publication Type:Journal Article
- Keywords:
Methicillin resistance;
Staphylococcus aureus;
Drug tolerance;
Genes;
Drug resistance,multiple;
Child
- From:
Chinese Journal of Infectious Diseases
2013;31(11):641-645
- CountryChina
- Language:Chinese
-
Abstract:
Objective The aim of this study was to study the antibiotic resistance and resistance genes of methicillin-resistant Staphylococcus aureus (MRSA) in children from Shanghai area,and to determine the relationship between phenotypic and genotypic resistance profiles.Methods In this study,a total of 37 MRSA strains isolated from clinical specimens of hospitalized patients in Children's Hospital of Fudan University from March 2009 to November 2011 were collected.The mecA,ermA,ermB,ermC,aac (6') /aph (2),aph (3')-Ⅲ,ant (4',4),and qacA genes were detected by polymerase chain reaction (PCR).Resistance to antibiotics was detected by agar dilution tests.The data analysis was done by chi square test.Results Among the 37 MRSA isolates,all (100.0 ％) were mecA gene positive,9 (24.3％) were ermB gene positive,none was ermA/C gene positive,21 (56.8％) were aac (6')/aph (2) gene positive,10 (27.0％) were aph (3')-Ⅲ gene positive,6 (16.2％) were ant(4',4) gene positive,and 9 were qacA gene positive (24.3％).The positive rate of aac(6')/aph(2) in hospital acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) was significantly higher than that of community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) (85.7％ vs18.8％,x2=60.340,P=0.000).Among the 37 MRSAisolates,37 (100.0％) were resistant to penicillin,ampicillin-sulbactam,cefazolin,cefoxitin and cefuroxime.The 37 isolates were all susceptible to teicoplanin,vancomycin,and linezolid.The resistant rates to gentamicin,erythromycin,clindamycin,sulfamethoxazole,fosfomycin,rifampicin,and levofloxacin were 51.4％ (19/37),81.1％ (30/37),51.4％ (19/37),16.2％ (6/37),27.0％ (10/37),37.8％ (14/37) and 54.0％ (20/37),respectively.Compared with CA-MRSA,HAMRSA isolates had significantly higher resistance rates to gentamicin (12.5％ vs 81.0％; x2 =17.033,P=0.000),levofloxacin (31.2％ vs 71.4％; x2 =5.903,P=0.017),and rifampin (6.2％ vs 61.9％; x2=11.959,P=0.001).The rate of gentamicin resistance in aac(6')/aph(2) gene carrying strains was significantly higher than strains not carrying the gene (x2 =29.757,P=0.000).Conclusions MRSA in children carry a variety of drug-resistant genes,showed multi-drug resistance.HA-MRSA carries more resistance genes,and has higher rates resistance to antimicrobials than CA-MRSA.
