July 14, 2016

Clinical Management for Emerging Antimicrobial-Resistant Neisseria gonorrhoeae

Overview

Antibiotic-resistant gonorrhea is a public health issue. CDC estimates there are more than 800,000 new gonorrhea infections each year. Left untreated, it can cause pelvic inflammatory disease in women, which can lead to serious reproductive complications including tubal infertility, ectopic pregnancy, and chronic pelvic pain. Prevention relies largely on prompt detection and effective antimicrobial treatment; however, treatment has been compromised by the evolution of antibiotic resistance to the antibiotics used to treat gonorrhea.
Since 2012, the Centers for Disease Control and Prevention (CDC) has recommended dual therapy with a single dose of 250 mg of intramuscular ceftriaxone in combination with 1 gram of oral azithromycin. This recommendation was made to preserve the last highly effective class of antibiotics left to treat gonorrhea (i.e., cephalosporins) for as long as possible after laboratory data suggested that the oral cephalosporin, cefixime, was becoming less effective. Today, this combination therapy is the only recommended treatment option available for gonorrhea.
Clinicians should not treat gonorrhea with only azithromycin. Surveillance data suggest that azithromycin resistance might be emerging. In addition, data suggest the use of azithromycin as a monotherapy to treat gonorrhea might promote the emergence of azithromycin-resistant gonorrhea. Clinicians must follow gonorrhea dual therapy recommendations and can find the most up-to-date gonorrhea treatment guidance within CDC’s STD Treatment Guidelines.

Surveillance

Although azithromycin is part of the recommended antimicrobial treatment for gonorrhea, a  recent analysis of gonorrhea specimens from CDC’s sentinel surveillance system, the Gonococcal Isolate Surveillance Project (GISP), shows declining susceptibility to azithromycin. Specifically, the percentage of samples with reduced azithromycin susceptibility increased from 0.6% in 2013 to 2.5% in 2014. This is the highest percentage of specimens with reduced azithromycin susceptibility seen since monitoring for the drug began more than 20 years ago.
In contrast to previous antimicrobial resistance patterns, declining azithromycin susceptibility occurred in all parts of the country, especially in the Midwest, as well as among men who have sex with men (MSM), men who have sex with men and women, and heterosexuals.
Isolates with reduced azithromycin susceptibility were highly susceptible to ceftriaxone, and isolates with reduced ceftriaxone susceptibility were highly susceptible to azithromycin, suggesting that cases resistant to one drug would be cured by the second. This demonstrates the strength and importance of dual treatment.
It is too early to know if this decline in azithromycin susceptibility is a trend, but it is concerning because gonorrhea can rapidly develop resistance and widespread resistance could have major treatment implications. Not only is azithromycin part of the currently recommended therapy, it is the backbone of every alternative treatment.

Reporting

Clinicians should report apparent treatment failures to CDC recommended therapies to their local health department’s Sexually Transmitted Disease (STD) program. Health departments are encouraged to notify CDC of such cases by contacting Robert D. Kirkcaldy, MD, MPH (rkirkcaldy@cdc.gov; 404-639-8659). Additional resources and references for antibiotic-resistant gonorrhea are available online.

Prevention and Screening

The complications and spread of gonorrhea can also be prevented through screening. Key screening recommendations are as follows:

• Screen all sexually active women younger than 25 years, as well as older women with risk factors such as new or multiple sex partners or a sex partner who has a sexually transmitted infection.
• Screen sexually active MSM at anatomic sites of possible exposure at least annually.

Clinicians should also:

• Notify and treat sexual partners to prevent reinfection and help halt the spread of gonorrhea.
• Consider Expedited Partner Therapy (EPT) for heterosexual partners unable or unwilling to access care.

Please visit CDC’s STDs webpage for the most current information on STD treatment.