Allele‑specific duplex polymerase chain reaction to differentiate Mycobacterium abscessus subspecies and to detect highly clarithromycin‑resistant isolates.

On the basis of the structural differences of erm, we used a duplex polymerase chain reaction (PCR) to differentiate Mycobacterium abscessus subsp. abscessus and subsp. massiliense isolates and to detect the point mutations of 23S rRNA gene that confer a high level of resistance to clarithromycin. Subsp. massiliense strains occupying almost half of the clinical isolates can be simply identified, and their clarithromycin susceptibility can be rapidly determined.

Drug-resistance and Gene erm Existing in Meticillin-resistant Staphylococcus aureus / 中华医院感染学杂志

OBJECTIVE To investigate the resistance of meticillin-resistant Staphylococcus aureus(MRSA) and the occurrence of gene erm.METHODS ATB Staph and microdilute tests were performed to detect the susceptibility to 15 kinds of antibiotics in 50 strains of the S.aureus(SAU).Gene erm of these strains was detected by polymerase chain reaction(PCR).RESULTS There were no strains resistant to vancomycin,teicoplanin,fusidic acid and quinupristin-dalfopristin in 42 strains of MRSA detected.There were no strains sensitive to penicillin,oxacillin,gentamicin,tetracycline,ciprofloxacin and levofloxacin.Thirty-five strains habored gene erm in 42 strains of MRSA.The positive rate of gene erm was 83.3%.CONCLUSIONS The multiple-resistance of the MRSA is a serious issue.The resistance to erythromycin in MRSA is mediated by gene erm which encodes the methylase and changes the target site of drug action.