Demonstration of the presence of an OXA carbapenemase gene by PCR.
Carbapenemase-mediated carbapenem resistance in Acinetobacter is most often due to the production of an OXA-23-like, OXA-40-like or OXA-58-like carbapenemase. In addition, carbapenem resistance in Acinetobacter may be due to overexpression of an OXA-51-like carbapenemase. OXA-51-like carbapenemases are intrinsic in A. baumannii and normally expressed at low levels but they can be overexpressed following the insertion of an ISAba1 sequence element upstream of the OXA-51 gene.
To check for the presence of OXA-23-like, OXA-40-like, OXA-58-like and OXA-51-like genes, a multiplex PCR is used and contains primers for each of the four groups of OXA-type carbapenemases. Any Acinetobacter isolates that are carbapenem resistant, but only positive for OXA-51-like genes in the multiplex PCR, are tested by PCR for the ISAba1 insertion sequence.
This test is appropriate for carbapenem-resistant Acinetobacter or Pseudomonas isolates.
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Area |
Health Science |
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Lab name |
Antibiotic Reference Laboratory |
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Lab location |
Kenepuru Science Centre, Porirua |
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Test name |
OXA-23-like, OXA-40-like, OXA-58-like and OXA-51-like carbapenemase gene PCR |
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Organisms |
Acinetobacter and Pseudomonas |
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Requested for surveillance |
no |
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Notice required |
no |
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Routine turnaround time |
6 working days for reference specimens |
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Sample requirements |
Pure culture |
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Media requirements |
A slope of any medium that supports the growth of the organism |
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Pre-transport requirements |
Ambient temperature |
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Transport requirements |
Ambient temperature |
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Unacceptable sample types |
Clinical specimens will not be accepted. |
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How results reported |
The results will state whether OXA-23-like, OXA-40-like, OXA-58-like or OXA-51-like genes or the IS Aba1 insertion sequence were detected |
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Referral link |