A multi-drug-resistant isolate of Neisseria gonorrhoeae has been confirmed by the Public Health England (PHE) Reference Laboratory as resistant to the current recommended dual first-line therapy. The isolate has a ceftriaxone MIC of 0.5 mg/L and an azithromycin MIC of >256 mg/L (high-level azithromycin resistant, HLAziR).
On wider antimicrobial susceptibility testing, the strain was susceptible only to spectinomycin. This is the first global report of HLAziR N. gonorrhoeae which is also resistant to ceftriaxone.
The strain was isolated from a heterosexual man who had attended sexual health services in England in early 2018. The case reported one regular female partner in the UK, and a female sexual contact in south-east Asia a month prior to symptom onset. The case was treated empirically with ceftriaxone (1 g), and subsequently with spectinomycin. At test-ofcure (TOC) the urine NAAT was negative but the throat swab was culture positive; reinfection was excluded indicating treatment failure. The patient is being treated with IV ertapenem. The ertapenem MIC was low (0.032 mg/L) suggesting that this may be an effective therapy, although there are no defined breakpoints. The results of the next TOC investigation will be available in mid-April. Follow-up of the case and sexual contacts is ongoing.
The provisional test result from the UK sexual contact was negative. PHE is supporting clinical and microbiology teams in the management of the case and has formed an incident management team (IMT) to coordinate the investigation and contain spread.
Reference: UK case of Neisseria gonorrhoeae with high-level resistance to azithromycin and resistance to ceftriaxone acquired abroad. Health Protection Report. Volume 12, Number 11. March, 29, 2018. Accessible at: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/694655/hpr1118_MDRGC.pdf
Source: Public Health England