Detection of resistance genes

Test description

• Amplification ‘of’ genes by PCR.  Detection for vanA and vanB is done by in-house real-time duplex PCR. Detection for other ‘from’ genes (including vanD, vanE and vanG) is done by whole genome sequencing. 
• Amplification of cfr, (cfr(B), optrA and poxtA if linezolid resistant. Detection is done by in-house real-time PCR. 

Purpose of detection resistance genes

• Detection of vancomycin resistance in enterococci (van-genes)
• Detection of linezolid resistance in enterococci (cfr, cfr(B), optrA, poxtA) 

Criteria for performing this test

• See identification of enterococci
• Strains phenotypically resistant to vancomycin
• Strains that are phenotypically linezolid resistant.
• Suitable samples for detection of resistance genes
• Clean culture on plate with individual colonies

Instructions for transport

See identification enterococci

Unacceptable requests

• No clean culture
• Incomplete request form

Turn around time and analysis frequency

Frequency of analysis: 

• fromA/B: 1x per week
• fromD/E/G and cfr/cfr(B)/optrA/poxtA: 1x per 2 weeks

Turn around time: 

• TAT ofA/B: 8 days
• TAT ofD/E/G: 35 days

Reporting of test results

• How: via fax
• When: see schedule.