207. Implementation of a Rapid Molecular Assay for Determination of Neisseria gonorrhoeae Susceptibility in a Large Health System
Session: Poster Abstract Session: Diagnostics: Bacteriology, Sequencing, and Resistance
Thursday, October 27, 2016
Room: Poster Hall
  • Allan-Blitz - gyrA Assay Implementation.pdf (3.3 MB)
  • Background: In 2013 the Centers for Disease Control and Prevention declared the emergence of multi-drug-resistant Neisseria gonorrhoeae (NG) infections to be one of the top three urgent threats to public health. In response we developed a rapid molecular assay to detect alterations in the gyrase A (gyrA) genotype of NG species conferring fluoroquinolone-resistance. In November 2015, UCLA Health began routine gyrA genotype testing NG positive specimens from the Cobas CT/NG assay (Roche Molecular Systems, Pleasant, CA).

    Methods: We reviewed patient records for all laboratory confirmed NG cases between January 1st 2015 and May 5th 2016 to determine HIV-infection status, time-to-treatment and gyrA genotype results by anatomic site. At least one NG infection detected from a patient on a single date was considered a case. Infections in different anatomic locations were considered unique infections.

    Results: Among 199 patients (84% men; 35% HIV-infected), there were 221 cases and 233 unique NG infections. Of cases, 78 (35%) were treated the same day as specimen collection. The mean time to treatment among non-empirically treated cases (N=118) was 5.3 days (SD 4.8 days). Of 101 infections after routine genotyping began, 68 (67%) were successfully genotyped. Of those 46 (68%) were wild-type gyrA and 22 (32%) were mutated. Among the remaining 33 infections, 29 could not be genotyped (23 pharyngeal, 3 urethral, 2 rectal, 1 genital) and 4 were not attempted. Among cases, 202 (91%) were treated with ceftriaxone: 125 (95%) of 131 before assay introduction versus 77 (86%) of 90 after assay introduction (chi-square statistic=6.6; p-value=0.01). Among 23 cases with wild-type gyrA genotype NG infection treated at least two days after specimen collection, two (9%) were treated with ciprofloxacin.

    Conclusion: A large health system successfully implemented routine NG gyrA genotyping on NG positive specimens. Successful genotyping may depend on anatomic site of infection. Introduction of NG genotyping was associated with a significant reduction in ceftriaxone use.

    Lao-Tzu Allan-Blitz, MD Candidate, 2018, David Geffen School of Medicine, UCLA, Los Angeles, CA, Romney Humphries, PhD, Department of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA, Peera Hemarajata, MD, PHD, Clinical Microbiology, UCLA, Los Angeles, CA, Xiaoyan Wang, Ph.D, Department of Medicine Statistics Core, UCLA, Los Angeles, CA and Jeffrey Klausner, MD, MPH, Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA


    L. T. Allan-Blitz, None

    R. Humphries, None

    P. Hemarajata, None

    X. Wang, None

    J. Klausner, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.