Open Access Highly Accessed Research article

Decreased susceptibility of Neisseria gonorrhoeae isolates from Switzerland to Cefixime and Ceftriaxone: antimicrobial susceptibility data from 1990 and 2000 to 2012

Helen Kovari1*, Maria DG de Melo Oliveira2, Paula Hauser1, Severin Läuchli3, Jürg Meyer3, Rainer Weber1 and Reinhard Zbinden2

Author Affiliations

1 Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland

2 Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland

3 Division of Dermatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland

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BMC Infectious Diseases 2013, 13:603  doi:10.1186/1471-2334-13-603

Published: 26 December 2013



Neisseria gonorrhoeae can rapidly develop resistance to antimicrobial agents. Over the last years, decreased gonococcal susceptibility to third-generation cephalosporins, especially cefixime, emerged worldwide. Therefore, current international guidelines recommend dual therapy for gonorrhoea with ceftriaxone plus either azithromycin or doxycycline. Gonococcal susceptibility data in Switzerland are sparse.


We investigated the prevalence of antibiotic susceptibility of N. gonorrhoeae in specimens collected between 1990 and 2012 at the University of Zurich, Switzerland. Minimum inhibitory concentrations (MICs) for cefixime, ceftriaxone, ciprofloxacin, and penicillin were determined by Etests. The European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints were used to define reduced susceptibility.


A total of 320 isolates were tested. Between 1990 and 2006 all tested samples were susceptible to both cephalosporins. Subsequently, the prevalence of elevated MICs for cefixime increased to 10.4% (2007/2008), 11.5% (2009/2010), and 11.4% (2011/2012); and for ceftriaxone to 2.4% (2007/2008), 4.7% (2009/2010), and 0% (2011/2012), respectively. The prevalence of resistance to ciprofloxacin (72.7%) and penicillin (22.7%) was high in 2011/2012.


Decreasing susceptibility of N. gonorrhoeae to third-generation cephalosporins in Switzerland supports treatment recommendations with ceftriaxone plus azithromycin or doxycycline. Health-care providers need to be aware of possible treatment failures with cephalosporins. Continued surveillance of gonococcal antimicrobial resistance is essential.

Neisseria gonorrhoeae; Gonorrhoea; Antimicrobial resistance; Cephalosporins