C-160. Beneficiaries of Trichomonas vaginalis Molecular Analyte-Specific Reagent Testing in a Metropolitan Setting of High Sexually-Transmitted Disease Prevalence

E. Munson1, M. Napierala1, R. Olson1, T. Endes2, T. Block1;
1Wheaton Franciscan Lab., Wauwatosa, WI, 2Wheaton Franciscan Med. Group, Franklin, WI.

Background: Trichomoniasis is considered by many to be a significant sexually-transmitted disease (STD) in the spectrum of public health and primary care because of its purported association with agents such as HIV and Neisseria gonorrhoeae (Ng). However, its true significance may be grossly underestimated due to diagnostic modalities that exhibit poor sensitivity. Methods: An audit of Trichomonas vaginalis (Tv) wet mounts within a regional healthcare system (centered in a high-STD prevalence community) revealed that >97% of such requests emanated from two urban emergency departments, a suburban urgent care facility, and a regional outpatient physician group. On a retrospective basis, 1086 cryptically-encoded genital specimens in Gen-Probe (San Diego, CA) collection devices were tested with the transcription-mediated amplification (TMA)-based Tv analyte-specific reagent (ASR; Gen-Probe) at frequencies commensurate with routine clinic testing volume. Results of TMA-based Ng and Chlamydia trachomatis (Ct) assays and corresponding wet mount were recorded prior to decoding. Results: The rate of positive Tv ASR result (14.7%) doubled that of the wet mount (7.2%; P < 0.0002). Analogous increases were observed at one urban emergency department and within the regional outpatient physician group (P < 0.0002). No significant increase in ASR-positive rate was observed from the urgent care facility (P = 0.73) or from the urban emergency department that encountered a lower frequency of African American patients (P = 0.75). While positive Tv findings via wet mount did not provide a significant association with concomitant Ct or Ng infection overall, a positive Tv ASR was a better predictor of concomitant Ct or Ng infection (odds ratios 2.34 and 4.46, respectively; P < 0.0001). The increased rate of positive Tv ASR result was observed in both point-of-care (P = 0.02 versus wet mount) and laboratory (P = 0.003) testing. Conclusion: Tv ASR is a highly-sensitive assay that not only transcends issues of specimen integrity and microscopic acumen, but also, in defined populations, has an increased ability to predict the likelihood of additional STD.