Background Antimicrobial therapy is essential to control Neisseria gonorrhoeae (NG). The appearance of isolates with decreased susceptibility or resistant to third-generation cephalosporins (TGC) has raised several concerns. Recent clinical trials suggest that gentamicin could be an alternative for NG treatment, but no susceptibility data to this drug is available in European NG isolates. Objectives were: describe the epidemiological and antibiotic susceptibility profile to NG strains isolated.

Methods Descriptive retrospective study of NG strains isolated during 2011 and 2012. The susceptibility to cefixime, ceftriaxone, gentamicin and ciprofloxacin was performed using agar dilution (AD) and disc diffusion (DD) methods according to the CLSI guidelines.

Results A total of 275 NG strains were isolated: 143 urethral (52%), 47 rectal (17%), 44 pharyngeal (16%), 28 endocervical (10%), vaginal and 13 (5%), belonging to 225 patients (174 men (77.3%), 51 (22.7%) women). The average age was 33.32 years (15–58 years). About 80% of the samples (221) were from STD Clinics Infectious Service. 151 patients (67.1%) were symptomatic at the moment of diagnosis, 32 cases (14.2%) were detected during screening and 42 cases (18.7%) during contact tracing. Urethritis was the most common clinical manifestation in men and accounted 71, 3% of the cases.

All strains were susceptible to TGC by both methods. Ciprofloxacin showed 59.3% resistant strains by AD with low minor discordances between the two methods in 22 strains. 74.5% of the strains showed a MIC of 8 µg/ml to gentamicin (range: 2 – 16µg/ml), and inhibition zone in the DD method between 16 and 38 mm.

Conclusions During the study period we found no resistant strains to TGC, but it was recorded a high rate of resistance to ciprofloxacin. The susceptibility profile of gentamicin is similar to those published but further research is needed to establish clinical breakpoints and doing a treatment recommendation.