Clinical evaluation of a new Pap test-based method for screening of Chlamydia trachomatis and Neisseria gonorrhoeae using liquid-based cytology media.

OBJECTIVES: The majority of chlamydial and gonococcal infections in women are asymptomatic and, if left untreated, may result in serious sequelae. Simple and accurate testing of men and women at risk for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) is the single most effective strategy for control of sexually transmitted infections. New tests using easy-to-acquire samples, such as the Papanicolaou (Pap) test, need to be validated in an effort to expand and improve detection. The objective of this study was to determine the performance of a new nucleic acid amplification test using two liquid-based cytology media for the detection of CT and GC.

METHODS: The study was conducted in two phases at 11 geographically diverse, high- and low-prevalence sites. Three endocervical reference swabs as well as an endocervical SurePath or PreservCyt liquid cytology specimen sampled with a broom or brush/spatula were collected in a randomized order from each subject. Reference endocervical swabs were tested with three Food and Drug Administration-approved methods and compared to two new automated tests, the CT Q Amplified DNA Assay (CTQ) and the GC Q Amplified DNA Assay (GCQ).

RESULTS: For the SurePath phase, 1838 subjects were enrolled. The sensitivity and specificity of the CTQ assay were 95.0% and 99.7%, respectively, and the GCQ assay was 100% for both. In the PreservCyt phase, 2164 subjects were enrolled. The sensitivity and specificity of the CTQ assay were 94.1% and 99.8%, respectively, and the GCQ assay was 95.3% and 99.95%, respectively. There was no significant difference in the results.

CONCLUSIONS: In this investigation, high sensitivity and specificity of the CTQ and GCQ assays were demonstrated for samples collected in either of two liquid-based cytology media when compared with endocervical swabs. The results were similar in both collection methods (broom or brush/spatula) and in high- and low-risk populations.