The HVR Genotypes and Their Relationship with the Resistance of Methicillin-Resistant Staphylococci
10.3969/j.issn.1672-173X.2001.02.003
- VernacularTitle:耐甲氧西林葡萄球菌HVR基因分型及其与耐药性的关系
- Author:
Fang LIAO
1
;
Xinjian FAN
;
Xiaoju LÜ
;
Ping FENG
Author Information
1. the First Affiliated Hospital WCUMS
- From:
Journal of Sichuan University (Medical Sciences)
2001;32(2):167-171
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the HVR-PCR genotype of methicillin-resistant Staphylococci in local hospitals and compare it with the antibiograms, with aview to selecting effective antibacterial agents, moreover, to discuss preliminarily its role in molecular epidemiology. Methods The minimal inhibitory concentrations(MICs) of 86 MRSA, 10 MRSE(Mcr S.epidemidis), 5 MSSE(Mcs S.epidemidis), 8 MRSH(Mcr S. haemolyticus) and 5 MSSH(Mcs S. haemolyticus) clinical isolates collected from 4 local hospitals were tested by serial two-fold agar dilution method; their DNA were extracted by moved basic lytic method, whose polymerase chain reaction(PCR) products amplified, based on the size of mec-associated hypervariable region(HVR) were analyzed by PAG vertical and agarose gel electrophoresis. Results MRSA, MRSE and MRSH were grouped into 4, 3 and 2 HVR genotypes respectively according to the size of the PCR products. The PCR products amplified from 9 of 10 MRSE isolates were the same as the products amplified from MRSA isolates. MRSA strains in this study were mainly HVR genotypes A and D, which accounted for 52.32% and 39.53%； Genotypes B and C were the most multi-drug resistant, but genotype D was multi-sensitive. The Ⅰ genotype of MRSE was multi-drug resistant, but its genotype Ⅲ was multi-drug sensitive. The genotype a of MRSH was more resistant than genotype b. Conclusion These results suggest that HVR-PCR genotype method is an easy and fast method for epidemiological investigation of nosocomial infections caused by MRSA， and it is helpful for clinical selection of antibacterial agents. This method can compare the mec determinants of MRSA and Mcr CNSt isolates and hence to search for the origin of the mec determinant.
