title: Comparison of nucleic acid amplification assays with BD affirm VPIII for diagnosis of vaginitis in symptomatic women.
abstract: A commercially available, nonamplified, nucleic acid probe-based test system (BD Affirm VPIII) was compared with nucleic acid amplification (NAA)-based assays for determining the etiology of vaginitis in a cohort of 323 symptomatic women. First, a semiquantitative, multiplexed PCR assay (BV-PCR) and the Affirm VPIII Gardnerellavaginalis test were compared with a unified bacterial-vaginosis (BV) reference standard incorporating both Nugent Gram stain scores and Amsel clinical criteria. In the evaluable population of 305 patients, BV-PCR was 96.9% (191/197) sensitive and 92.6% specific (100/108) for BV, while Affirm VPIII was 90.1% sensitive (179/197) and 67.6% specific (73/108). Second, a multiplexed PCR assay detecting Candida albicans and Candida glabrata (CAN-PCR) was compared with the Affirm VPIII Candida test using a reference standard for vulvovaginal candidiasis (VVC) of yeast culture plus exclusion of alternate vaginitis etiologies. In the population evaluated (n = 102), CAN-PCR was 97.7% sensitive (42/43) and 93.2% specific (55/59) and Affirm VP III was 58.1% sensitive (25/43) and 100% specific (59/59) for VVC. Finally, the results of a commercial NAA test (GenProbe Aptima Trichomonas vaginalis assay; ATV) for T. vaginalis were compared with the Affirm VPIII Trichomonas vaginalis test. In the absence of an independent reference standard for trichomonal vaginitis (TV), a positive result in either assay was deemed to represent true infection. In the evaluable cohort of 388 patients, the sensitivity of ATV was 98.1% (53/54) versus 46.3% (25/54) for Affirm VPIII. The diagnostic accuracy of the combined NAA-based test construct was approximately 20 to 25% higher than that of the Affirm VPIII when modeled in populations with various prevalences of infectious vaginitis.
authors.affiliation: ViroMed Laboratories Inc., Minnetonka, Minnesota, USA.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Cartwright
authors.forename: Bryndon D
authors.initials: BD
authors.lastname: Lembke
authors.forename: Kalpana
authors.initials: K
authors.lastname: Ramachandran
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Body
authors.forename: Melinda B
authors.initials: MB
authors.lastname: Nye
authors.forename: Charles A
authors.initials: CA
authors.lastname: Rivers
authors.forename: Jane R
authors.initials: JR
authors.lastname: Schwebke
mesh_terms: D000328:Adult; D002181:Candidiasis, Vulvovaginal / Q000175:diagnosis* / Q000382:microbiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D014247:Trichomonas Vaginitis / Q000175:diagnosis* / Q000469:parasitology; D016585:Vaginosis, Bacterial / Q000175:diagnosis* / Q000382:microbiology; D055815:Young Adult