Stepwise diagnosis of Trichomonas vaginalis infection in adolescent women.
The objective of this study was to examine the effects of clinical factors and of the type and timing of a secondary test in improving the sensitivity of Trichomonas vaginalis detection in young women over that of a wet mount alone. For this purpose, sexually active adolescent women (n = 345) were recruited from a hospital teen clinic or emergency department. Following an interview and a pelvic exam, four primary T. vaginalis tests (wet mount, culture, a rapid test, and a nucleic acid amplification test [NAAT]) were performed on vaginal swabs. If the wet-mount result was negative, two secondary tests (culture and a rapid test) were performed on the used wet-mount swab and saline. A positive result by any of the four primary tests was considered a true T. vaginalis-positive result. The prevalence of T. vaginalis was 18.8% overall and 8.8% in the 307 wet-mount-negative women. There was 100% concordance between primary and secondary rapid tests. Secondary culture was 80% sensitive compared to primary culture. The likelihood of a positive rapid test increased with increasing time between specimen collection and testing. A wet mount followed by a rapid test was the most sensitive strategy using two tests (86.4%; confidence interval [CI], 75.3 to 93.4%). Limiting secondary testing to those with multiple partners resulted in a lower sensitivity (73.9%; CI, 61.5 to 84%) that was not significantly better than that of the wet mount alone (58.5%; CI, 45.6 to 70.6%). We conclude that a rapid test can be delayed or performed on a used swab with no loss of sensitivity. Until a NAAT for T. vaginalis is commercially available, a stepwise approach using an additional rapid test for wet-mount-negative women is recommended for adolescent women regardless of clinical factors.
Pattullo
Lucia
L
Division of Adolescent Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., ML 4000, Cincinnati, OH 45229-3039, USA
Griffeth
Sarah
S
Ding
Lili
L
Mortensen
Joel
J
Reed
Jennifer
J
Kahn
Jessica
J
Huppert
Jill
J
D000293:Adolescent; D000818:Animals; D005260:Female; D006801:Humans; D010274:Parasitology / Q000379:methods*; D015995:Prevalence; D012680:Sensitivity and Specificity; D014245:Trichomonas Infections / Q000175:diagnosis* / Q000453:epidemiology*; D014246:Trichomonas vaginalis / Q000302:isolation & purification*; D055815:Young Adult