Validation of Gen-Probe APTIMA Trichomonas vaginalis Analyte Specific Reagent for Use in Public Health Clinical Laboratories to Detect Trichomonas vaginalis in Urine Sediment

Background:
Trichomonas vaginalis (TV) infection is one of the most common curable sexually transmitted diseases (STDs) and untreated infection has been associated with significant morbidity including preterm delivery and increased risk of HIV infection. Traditional detection methods for TV in public health clinical laboratories have drawbacks with the most significant being low sensitivity. Urine samples, which are used in the molecular detection of other STDs in public health clinical laboratories with high sensitivity, have the potential to be used in amplified assays to detect TV in these settings.

Objective:
To validate Gen-Probe APTIMA Trichomonas vaginalis Analyte Specific Reagent (ASR) for TV testing in a public health clinical laboratory.

Method:
Urine samples were collected from Genesee County Health Department Adult Clinic patients (n=637). A portion of each sample was microscopically evaluated for TV, another was used to culture TV, and a third was tested using Gen-Probe ASR to molecularly detect the presence of TV nucleic acid in the sample. The sensitivity and specificity for each assay was established.

Result:
Results show the Gen-Probe ASR to be 99.5% sensitive in detecting infection with TV while microscopic detection and culture have sensitivities of 50.0% and 61.9%, respectively. Prevalence of TV infection in this population was high, 13.2%.

Conclusion:
The Gen-Probe ASR was validated for use in this public health clinical laboratory. It detected significantly more TV infections and revealed that up to 50% of TV infections are not being diagnosed in this public health clinic using current approved testing methods.

Implications:
Validation of Gen-Probe ASR for TV testing in this laboratory proves the significance of molecular assays in the public health sector and demonstrates the limitations of microscopic detection and culture. A more sensitive test permits the true epidemiology of TV infection to be determined and allows for increased diagnosis, treatment, and prevention.