Background The Austrian Society for Sexually Transmitted Diseases started a surveillance project in 2010 to evaluate the gonococcal resistance in Austria.
Methods In 2010 and 2011 a national network of 39 centres was established to collect 1569 gonococcal isolates and the anamnestic data of the patients. Gonococcal culture plates were sent from the participating laboratories to the Outpatient´s Center in Vienna, where gonococcal resistance testing was performed by disc diffusion test, agardilution breakpoint technique, agardilution, and Etest. The following antibiotics were tested: cefixime, ceftriaxone, penicillin, ciprofloxacin, azithromycin, tetracycline, spectinomycin, and gentamicin. Results were interpreted according to CLSI and EUCAST guidelines.
Results In Vienna, 1456 isolates were collected, whereas 111 strains were sent from the federal states. Of all collected isolates 87% were genital, 5% pharyngeal, and 7% rectal isolates, respectively. Gonococci were collected more often from men (56%) than from women, 10% of men reported homosexual contacts. A concurrent infection with Chlamydia trachomatis was observed in 15% of all patients.
While 2010 all isolates displayed susceptibility to third generation cephalosporines, in 2011 7 gonococcal strains were resistant to cefixime (MIC > 0.125 µg/ml) but still susceptible to ceftriaxone (MIC ≤ 0.125 µg/ml). Furthermore, an increase of MIC values for cefixime as well as for ceftriaxone was observed in 2011. Resistance to azithromycin increased from 1% in 2010 to 1.5% in 2011. Resistance to quinolones was detected in 58% in 2010 rising to more than 60% in 2011, respectively.
Conclusion Third generation cephalosporines still represent the most appropriate drug for gonococcal therapy. As Azithromycin resistance is low in Austria it is suitable for alternative therapy especially in case of coinfection with C. trachomatis. Due to the increasing MIC values for cephalosporines and the rising rates for azithromycin resistance it is highly recommended to determine the resistance pattern of the respective gonococcal strain by culture performance.
- antibiotic resistance
- Neisseria gonorrhoeae