(P190) Molecular-based Testing for the Detection of Rectal and Oropharyngeal* Chlamydia trachomatis and Neisseria gonorrhoeae Infections

Tuesday, July 25, 2023

16:00 – 18:00 CST

Primary Presenter(s)

Paula B. Dixon, BS, AS

Laboratory Manager
University of Alabama at Birmingham
Birmingham, Alabama, United States

Co-author(s)

CC

Catherine L. Cammarata, BS in Medical Technology

Manager of Health Services
Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center
New Orleans, Louisiana, United States
ST

Stephanie Taylor

Professor of Medicine & Microbiology
Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center
New Orleans, Louisiana, United States
EL

Elizabeth Lockamy

Sr. R&D Manager
Becton, Dickinson and Company, BD Life Sciences – Integrated Diagnostic Solutions
Sparks, Maryland, United States
JI

Jordan Ippolito

Clinical Project Specialist
BD, United States
BV

Barbara Van Der Pol, PhD, MPH

University of Alabama at Birmingham, United States

Background

Extragenital (rectal and oropharyngeal) infections with Chlamydia trachomatis and Neisseria gonorrhoeae have been identified using nucleic acid amplification tests (NAATs). Extragenital infections with these organisms are more common than previously recognized, and they may be more difficult to treat than genital infections. However, the limited quantity of commercially available tests approved for use with rectal and oropharyngeal specimens has hindered widespread routine testing using these specimen types.

Methods

An investigator-initiated study was conducted involving three manufacturers of NAATs used for CT/GC testing using urogenital specimen types. Collaboration among the manufacturers led by an independent investigator allowed for aliquots of remnant specimens in Thin-Prep^® PreservCyt^® Solution containing expressed rectal or oropharyngeal swabs to be tested on the BD COR instrument using the BD CTGCTV2 assay in this study. Three US laboratory sites tested n=4610 specimens (n=2292 rectal [n=132 CT positive, n=95 GC positive] and n=2318 oropharyngeal [n=24 CT positive, n=97 GC positive]) obtained as remnant samples as described above. The ThinPrep aliquots were added to the BD Molecular Swab tubes for testing on the BD COR. The specimens were collected from both high and low prevalence clinical sites that included sexually transmitted disease (STD), family planning, and obstetrics and gynecology clinics (OB/GYN). The final anatomical site infected status determined using a composite reference standard with concordance of 2 out of 3 comparator results. Sensitivity and specificity were calculated for each target and specimen type.

Results

Target by specimen type	Sensitivity (95% CI)	Specificity (95% CI)
CT, Rectal Specimens	97.7% (93.5%, 99.2%)	99.4% (99.0%, 99.7%)
CT, Oropharyngeal Specimens	100.0% (86.2%, 100.0%)	99.8% (99.5%, 99.9%)
GC, Rectal Specimens	95.8% (89.7%, 98.4%)	99.8% (99.5%, 99.9%)
GC, Oropharyngeal Specimens	92.8% (85.8%, 96.5%)	99.5% (99.1%, 99.7%)

Conclusion

Based on the pre-specified acceptance criteria, all sensitivity and specificity requirements of the BD COR System per target and per specimen type were met. The BD CTGCTV2 assay on the BD COR System could help bridge the gap in need and availability of widespread extragenital testing for CT and NG.

*Pending 510(k) clearance, not available for sale in the United States.