Details of the latest case where published in the Drug Surveillance Report this month

Irish health officials have highlighted the global threat of antimicrobial resistance in gonorrhoea after details emerged of only the second case ever of cephalosporin resistant gonorrhoea in a heterosexual man in Ireland.

There has only ever been one previous case of gonorrhoea with a ceftriaxone minimum inhibitory concentration (MIC) above the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoint of 0.12mg/L reported in Ireland, and that occurred in 2012.

Details of the latest case were published this month in the Drug Surveillance Report from the Health Protection Surveillance Centre (HPSC).

The report notes: “These cases illustrate the global threat of antimicrobial resistance in gonorrhoea and highlight the importance of Ireland having a robust national surveillance system for gonorrhoea antimicrobial resistance.”

In the recent case, the patient was initially reviewed for genito urinary symptoms by a GP in late July and was started on empiric therapy for a urinary tract infection.

The patient, who reported recent sexual contact with a female during a visit to Asia, later attended a specialised sexually transmitted infection (STI) service with symptoms of urethral discharge and dysuria.

The HPSC report adds: “In accordance with the National Guidelines for the Prevention and Control of Gonorrhoea and for minimising the impact of Antimicrobial Resistance in Neisseria gonorrhoeae, a urethral swab was taken for culture and microscopy; and a first void urine (FVU) sample was taken for nucleic acid amplification test (NAAT).”

The man was later treated with 500mg ceftriaxone (intramuscular) and 1g azithromycin (oral).

Further phenotypic and genotypic analysis was performed in the Department of Clinical Microbiology, St James’s Hospital, which confirmed a gonorrhoea infection.

Antimicrobial susceptibility testing in the National Interim Gonococcal Reference Laboratory indicated that the isolate was resistant to ceftriaxone (MIC: 0.5 mg/L), cefixime and ciprofloxacin; and was susceptible to azithromycin (MIC: 0.125 mg/L), spectinomycin and tetracycline.

The patient was recalled early to the clinic, eight days following the initial visit.

At this point, the patient was asymptomatic, a FVU sample was taken and empirical treatment with 2g azithromycin (oral) was administered. The FVU sample was taken for Test of Cure (ToC) and it was subsequently reported negative for Neisseria gonorrhoeae by NAAT, indicating successful initial treatment.

Onward transmission of the ceftriaxone resistant isolate in Ireland is not likely as the patient reported that he had no sexual contact since his return to Ireland from Asia.

World Health Organization data show a disproportionately high burden of gonococcal disease and high levels of gonococcal antimicrobial resistance in Asia due to widespread and uncontrolled use of antimicrobials and difficulties in conducting antimicrobial resistance surveillance in resource-poor settings.

These issues highlight the importance of promoting sexual health among international travellers, in particular those travelling to Asia.

peter.doyle@imt.ie