Ciprofloxacin cured Gyrase A wild-type Neisseria gonorrhoeae infections

Ciprofloxacin cured 100 percent of Gyrase A wild-type Neisseria gonorrhoeae infections, and physicians prescribed it significantly more frequently when they received electronic reminders of test results and recommendations, in a single-center study.

“Recent reports of untreatable gonorrhea have caused great concern. Treatment with ceftriaxone may be a major driver of resistance, and reducing its use may curb the emergence of resistance infections as said at an annual scientific meeting on infectious diseases.

The Centers for Disease Control and Prevention ranks multidrug-resistant N.gonorrhoeae third among all drug-resistant threats in the United States. As noted during an oral presentation at the meeting,beginning in the late 1990s strains of N.gonorrhoeae developed resistance to sulfanilamides, penicillin, tetracycline and fluoroquinolones, leaving only the extended-spectrum cephalosporins for empiric treatment. Recent reports of cephalosporin-resistant N.gonorrhoeae in other countries have raised the specter of untreatable gonorrhea.

Because antimicrobial resistance can shift in response to selective pressure, experts are exploring the use of antibiotics once considered ineffective for treating N.gonorrhoeae infections.  Researchers developed a real-time reverse transcription polymerase chain reaction test for a mutation of codon 91 in the gyrase A (gyrA)gene in N.gonorrhoeae that reliably predicts resistance to ciprofloxacin.

Test result takes 24-48 hours. The test is not Food and Drug Administration approved but has been validated in accordance with Clinical Laboratory Improvement Amendments. 

In November  2015, UCLA Health began gyrA genotyping all N.gonorrhoeae-positive specimens, and in May 2016, it began sending providers electronic reminders of genotype results and treatment recommendations. For gyrA wild-type infections, UCLA Health recommends 500 mg oral ciprofloxacin.

Genotyping of 582 cases tested between January 2015 and November 2016 showed that 43 percent were wild type. Another 27 percent cases were mutant (resistant) and 30 percent had an indeterminate genotype. Before UCLA Health implemented its electronic reminder system, physicians treated only three percent of cases with ciprofloxacin. After the reminder system went into effect, this proportion rose to 18 percent (P=.002).

Initial test-of-cure data are promising. All 25 patients with wild-type infections who received ciprofloxacin and returned 7-90 days later tested negative for N.gonorrhoeae. Culture sites included the urethra (seven cases), pharynx (seven cases), rectum (seven cases), and genitals (four cases). Prior studies have demonstrated that reminder notifications improve uptake of antimicrobial stewardship.

Other health centers should consider implementing the gyrA assay, and using reminder notifications may improve uptake by providers.