Performance of Nucleic Acid Amplification Tests for the Detection of NG and CT

The purpose of this study was to use participant samples to simultaneously evaluate three nucleic acid amplification tests (NAATs) diagnostic platforms.

Background \& Significance: Infections due to Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) are major threats to public health. Most CT and NG infections are asymptomatic, but infection can lead to serious sequelae, including infertility, chronic pelvic pain, adverse obstetrical outcomes, increased risk of acquiring the human immunodeficiency virus (HIV), and disseminated infection.

There has also been growing concern over antibiotic resistance. In 2013, the US Centers for Disease Control and Prevention (CDC) classified drug-resistant NG as one of the three urgent-level resistant bacteria. Improved detection of extragenital NG is thought to be a crucial component of adequate treatment and for prevention of further resistance.

Currently, the CDC recommends using NAATs to screen and diagnose for NG and CT in the genitourinary tract due to their superior sensitivity compared to traditional culture methods. There are currently no FDA-approved commercial NAAT tests for the detection of pharyngeal and rectal NG or CT infections. The goal of this study is to evaluate the diagnostic performance of three NAAT assays for detection of extragenital NG and CT infections.

Design \& Procedures: A cross-sectional, single visit study evaluating the performance of three commercial NAATs to detect NG and CT in the rectum and pharynx. A fourth NAAT will be used as a tiebreaker. The performance of the fourth NAAT will not be evaluated. Each manufacturer will provide a specific swab collection kit and transport media.

This research study will take place at healthcare clinics that focus on sexually transmitted infections, women's health, student health, family planning, and lesbian, gay, bisexual, and transgender (LGBT) health. This research will include specimens collected from adult males, females, and transgender persons seeking sexually transmitted infection (STI) testing at the participating study clinics. Both symptomatic and asymptomatic participants are included in the study population.

Potential participants will be identified, assessed for eligibility, and asked to provide oral informed consent. If a potential participant agrees to take part in the research, the participant will have eight total swabs collected: four swabs from the pharynx and four swabs from the rectum. The swabs needed for routine clinical care are taken first prior to collection of the research study swabs. All study procedures take place during one clinic visit; there are no follow-up visits as part of the study. Participants continue with routine clinical care as directed by their medical providers.

Subject participation is confidential and anonymous. The results of the tests and participation in this research are not placed in the participant's medical records.

Each study swab is used for a specific NAAT and tested at one of the two reference testing laboratories. The Anatomic Site Infection Status (ASIS) is defined by the results of the two other NAATs, and, if necessary, results from the tiebreaker NAAT. Each anatomic site is considered in isolation. If fewer than four swabs at an anatomic site are completed, then the test results from that specific anatomic site are excluded from analysis.

Eligibility Criteria:
Inclusion Criteria:

1. Attending a participating clinic for evaluation of sexually transmitted infections (STIs)
2. ≥18 years of age at date of screening
3. Able and willing to provide informed consent
4. Willing to comply with study procedures, including collection of 4 swabs each from the pharynx and rectum for NG and CT testing

Exclusion Criteria:

1. Receipt of any systemic antibacterial drug in the past 14 days
2. Receipt of myelosuppressive chemotherapy in the past 30 days