Trends in antimicrobial susceptibility of Neisseria gonorrhea in a sexually transmitted disease (STD) clinic in central Israel, 2009 to 2014

Background: We assessed antibiotic susceptibility to all N. gonorrhea isolates from patients attending a walk in STD clinic during 1.2009-7.2014.

Methods: Strains were isolated from clinical and screening specimens. Susceptibility to penicillin, ceftriaxone, tetracycline, ciprofloxacin azithromycin and spectinomycin was performed using Etests. Gentamicin susceptibility by Etest was performed since 2011. EUCAST criteria were used to define breakpoints. We calculated geometrical MIC means. ANOVA was used for comparisons.

Results: 338 isolates were tested. Mean age was 34. Samples were taken from urethral discharge 190 (56.2%), pharynx 130 (38.5%) and rectum (5.3%). See table for antibiotic susceptibility (year, % sensitive/resistant). All isolates remained susceptible to ceftriaxone. There was significant decline in susceptibility for tetracycline and azithromycin. All isolates were sensitive to spectinomycin, but there was a significant rise in MICs within the susceptible range. None had MIC>8mg/l for gentamycin but a significant trend towards higher MICs was noted. Ciprofloxacin susceptibility remained ~50%.

Conclusion: Rate of susceptible isolates to tetracycline, and azithromycin decreased significantly since 2013. MICs are also increasing within the susceptible range for tetracycline, azithromycin, spectinomycin and gentamicin. This emphasizes the importance of surveillance.

	Penicillin N=338	Ceftriaxone N=338	Tetracycline* N=3382009	Ciprofloxacin N=338	Azithromycin* N=337	Spectinomycin* N=338	Gentamicin* N=115
2009	0.358 4.2/14.6	0.008 100/0	0.817 60.4/25.0	0.140 50.0/50.0	0.233 81.2/10.4	8.813 100/0	-
2010	0.417 13.3/16.7	0.006 100/0	0.880 66.7/20.0	0.163 46.7/53.3	0.183 93.3/0	7.972 100/0	-
2011	0.244 14.3/14.3	0.005 100/0	0.806 83.9/3.6	0.020 75.0/25.0	0.224 98.2/0	8.540 100/0	3.984 -
2012	0.266 15.8/13.2	0.005 100/0	0.570 81.6/15.8	0.068 61.8/38.2	0.180 94.7/0	7.942 100/0	3.932 -
2013	0.470 2.3/18.6	0.005 100/0	1.483 59.3/36.0	0.125 54.7/45.3	0.265 72.1/5.8	10.567 100/0	5.499 -
2004	0.479 7.1/14.3	0.006 100/0	4.356 35.7/54.8	0.570 35.7/64.3	0.240 3.8/0	12.325 100/0	6.397 -

MIC geomtric means, % suceptible/resistant. *P<0.05