Resistance trends in Neisseria gonorrhoeae in southwestern Ohio

Fluoroquinolone-resistant Neisseria gonorrhoeae strains originated in Eastern Asia in the 1980s; first appeared in United States during the early 1990 s in Hawaii, and subsequently spread to California and the continental US shortly after 2000. In 2007, the CDC recommended that fluoroquinolones should not be used as first-line therapy and recommended monitoring local resistance patterns to guide treatment recommendations. The Public Health-Dayton and Montgomery County STD Clinic tested N. gonorrhoeae isolates in 1996, 2001 and since 2006 to monitor susceptibility trends in the region.

Cultures for N. gonorrhoeae were collected from male and female patients presenting to the Public Health-Dayton and Montgomery County STD Clinic. In 1996 and 2001, consecutive isolate were collected. Since 2006, 10 isolates were randomly selected per month. Susceptibility testing was performed using Etest strips. Susceptibility results were interpreted following the Clinical Laboratory Standards Institute guidelines.

In 1996, 102 isolates were tested; 85% were susceptible to ciprofloxacin (15% intermediate, 0% resistant) and 52% susceptible to tetracycline (39% intermediate, 9% resistant). In 2001, 106 isolates were tested; 100% were susceptible to ciprofloxacin and 76% susceptible to tetracycline (22% intermediate, 2% resistant). From 2006-2008, 286 isolates were tested; 98% were susceptible to ciprofloxacin (2% resistant), 60% susceptible to tetracycline (36% intermediate, 4% resistant) and 99% were susceptible to azithromycin.

Rates of ciprofloxacin resistance remain low in Montgomery County. Azithromycin is another potentially useful treatment; tetracycline is not acceptable for empirical therapy.