Bacterial Vaginosis (BV), NAAT
Test Mnemonic
BVAMP
CPT Codes
- 81513 - QTY (1)
LOINC ®
74635-4
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| One | Vaginal | Aptima Multitest Collection Kit | Ambient | Ambient | Vaginal Multitest (orange tube pink swab): A vaginal swab is the only acceptable specimen. Carefully insert the swab into the vagina about 2 inches past the introitus and gently rotate the swab for 10-30 seconds. Make sure the swab touches the vaginal walls so that moisture is absorbed by the swab. Vaginal swab specimens may be patient-collected in a clinical setting when a pelvic exam is not otherwise indicated (https://www.hologic.com/package-inserts/swab-collection-instructions-vaginal-main-english#4257225834-454981651). Place swab into Aptima transport tube. Snap off swab at the score line, and close the tube tightly. |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 15⁰C to 30⁰C, 30 days. |
| Refrigerated | 2⁰C to 8⁰C, 30 days. |
| Frozen | -20⁰C to -70⁰C, 90 days. |
Days Performed
Mon - Sun
Turnaround Time
1 - 4 days
Methodology
| Name | Description |
|---|---|
| Transcription-Mediated Amplification |
Reference Range
Special Info
Microbiology Preanalytic Guidance: http://portals.ccf.org/plmi/Laboratory-Medicine/Microbiology-Specimen-Collection-Transport-Information. The specimen must be a vaginal swab collected and transported using the Aptima Multitest Swab Specimen Collection Kit. Up to two tests can be run on a single Aptima Multitest Swab specimen (ie. TRVAMP+BVAMP or CVTV+BVAMP) - if specimen sources have been correctly selected, the shared tests will print on the same label. Do not place more than one label on a single collection tube. Specimens collected from a non-vaginal source, with an inappropriate or expired collection device, or containing >1 swab may be rejected. Related alternative orders: 1. BVSTN: in-house vaginal smear gram stain for bacterial vaginosis diagnosis by Nugent score (recommended over NAAT when ordered alone due to lower patient cost). 3. BVCNSM: in-house vaginal smear gram stain for bacterial vaginosis diagnosis by Nugent score and microscopic exam for yeast (use when both BV and uncomplicated vulvovaginal candidiasis are on the differential).
Clinical Info
Vaginitis syndrome is characterized by a spectrum of conditions including vaginal and vulvar irritation, odor, discharge and pruritus. Causes of vaginitis include mechanical and chemical factors (feminine hygiene products, contraceptive materials, etc.) as well as infectious agents. Up to 90% of infectious vaginitis cases are caused by bacterial vaginosis (BV), vulvovaginal candidiasis (candida vaginitis, CV) and trichomoniasis (Trichomonas vaginalis, TV). BV has been diagnosed in 22-50% of symptomatic patients, CV in 17-39%, and TV in 4-35%. BV is characterized by a change in the vaginal microbiota dominated by Lactobacillus species to a polymicrobial anaerobe-dominated microbiota that includes Gardnerella vaginalis, Atopobium vaginae, Prevotella, Bacteroides, Peptostreptococcus, Mobiluncus, Sneathia (Leptotrichia), Mycoplasma, and BV associated bacteria. BV can be diagnosed using clinical criteria (i.e., Amsel’s diagnostic criteria), by determining the Nugent score from a vaginal Gram stain (order code BVSTN), or by nucleic acid amplification tests (NAAT). The latter can be associated with higher patient costs, but can be more convenient if microscopy is locally unavailable, or the same swab is already being collected for gonorrhea, chlamydia, and/or trichomonas testing. The Aptima BV assay is an FDA-cleared in vitro NAAT that utilizes real time transcription-mediated amplification (TMA) for detection and quantitation of ribosomal RNA from bacteria associated with bacterial vaginosis (BV), including Lactobacillus (L. gasseri, L. crispatus, and L. jensenii), Gardnerella vaginalis, and Atopobium vaginae. The assay uses an algorithm to report a qualitative result for BV based on detection of target organisms, and does not report results for individual organisms. The assay is intended to aid in the diagnosis of BV on the automated Panther system using clinician-collected and patient-collected vaginal swab specimens from patients with a clinical presentation consistent with vaginitis and/or vaginosis.
Clinical Limitation
1. The performance of the assay has not been evaluated in patients <14 years of age. 2. Therapeutic failure or success cannot be determined with the assay since nucleic acid may persist following appropriate antimicrobial therapy. 3. A negative result does not preclude a possible infection because results are dependent on adequate specimen collection. Test results may be affected by improper specimen collection, technical error, specimen mix-up, or other factors. 4. The effects of tampon use and other specimen collection variables have not been assessed for their impact on assay detection. 5. Interference with the Aptima BV assay was observed in the presence of the following substances: Mucus (1.5% V/V), Vaginal Moisturizing Gel (0.5% W/V) and Tioconazole (5% W/V). 6. Additional microorganisms not detected by the Aptima BV assay such as Prevotella species and Mobiluncus species, Ureaplasma, Mycoplasma, and numerous fastidious or uncultivated anaerobes have also been found in women with BV, but are less associated with BV due to their relatively low prevalence, sensitivity, and/or specificity. 7. Cross-reactivity was observed with the Aptima BV assay in the presence of Lactobacillus acidophilus.
Clinical Reference
Workowski KA, Bachmann LH, Chan PA, Johnston CM, Muzny CA, Park I, Reno H, Zenilman JM, Bolan GA. Sexually Transmitted Infections Treatment Guidelines, 2021. MMWR Recomm Rep. 2021 Jul 23;70(4):1-187. doi: 10.15585/mmwr.rr7004a1. PMID: 34292926; PMCID: PMC8344968.