Prevalence of porA pseudogene deletion among Neisseria gonorrhoeae isolates referred to the UK’s Gonococcal Resistance to Antimicrobials Surveillance ProgramMartina Toby A , Pamela Saunders B , Michelle Cole B , Vlad Grigorjev B , Sarah Alexander B C and Catherine Ison B
A 56 Dean Street, Soho, London, W1D 6AQ, UK.
B Sexually Transmitted Bacteria Reference Unit, Public Health England, 61 Colindale Avenue, London, NW9 5EQ, UK.
C Corresponding author. Email: Sarah.Alexander@phe.gov.uk
Sexual Health 14(4) 392-393 https://doi.org/10.1071/SH16162
Submitted: 26 August 2016 Accepted: 22 February 2017 Published: 18 May 2017
porA pseudogene-negative Neisseria gonorrhoeae isolates produce false-negative results when examined by polymerase chain reaction (PCR) with porA pseudogene targets. In the present study, 533 representative gonococcal isolates received in 2011 via the Gonococcal Resistance to Antimicrobials Surveillance Program were examined to determine the prevalence of porA-negative isolates. Less than 0.4% (2/533) of isolates were found to be reproducibly negative with the porA real-time PCR but were confirmed as N. gonorrhoeae with molecular, biochemical and immunological confirmatory tests. Sequencing revealed both isolates contained the Neisseria meningitidis porA gene. Low prevalence indicates that although these isolates do not present a major public health problem, microbiologists should remain vigilant.
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