Methodology
Transcription Mediated Amplification (TMA) and Dual Kinetic Assay (DKA).
Turn Around Time (TAT)
4 days
Test Description
The APTIMA Combo 2 Assay is an automated, target amplification nucleic acid probe test that utilizes target capture for the in vitro qualitative detection of ribosomal RNA (rRNA) of Chlamydia trachomatis (CT) in urogenital specimens.
Clinical Significance
Infection with Chlamydia trachomatis (CT) is the most frequently reported bacterial sexually transmitted disease (STD) in the United States. CT can cause urethritis, cervicitis, proctitis, conjunctivitis, endometritis, and salpingitis; if left untreated, the infection may ascend to the uterus, fallopian tubes, and ovaries causing pelvic inflammatory syndrome, ectopic pregnancy, and tubal factor infertility. Reiter’s syndrome (urethritis, conjunctivitis, arthritis, and mucocutaneous lesions) has also been associated with genital CT infection. Many infections remain asymptomatic, and high numbers of infected patients may not seek care.
Specimen Requirements
Urine (First catch, preferred), Vaginal/Endocervical Swab, ThinPrep, (See OB/GYN Specimen Collection Media)
Sample Collection, Storage and Transport
A: Urine Collection for Male (using Aptima PCR Urine Kit)
- Note expiry date on sample collection vial. Do not use expired vials.
- Patients should not have urinated for at least one hour prior to specimen collection.
- Direct the patient to collect first-catch urine (approximately 20 to 30 mL of the initial urine stream) into a urine collection cup. The collection of larger volumes of urine may reduce test sensitivity.
- The first catch urine should be immediately transferred into the Aptima PCR Media tube using the provided disposable pipette. (Note: If the urine specimen cannot be transferred immediately, it can be stored at 2°C to 30°C for up to 24 hours.)
- The correct volume of urine has been added when the fluid level is between the two black lines on the tube label.
- Re-cap the Aptima urine specimen transport tube tightly. Label the vial with two patient identifiers, place the vial and pathology request form in a specimen bag, transport and store 2°C to 30°C for up to 30 days of collection.
B: Vaginal swab – Clinician collection (using Aptima Unisex Swab Kit)
- Note expiry date on sample collection vial. Do not use expired vials.
- Collect: Partially peel open the swab package and remove the swab. Remove the blue- shaft specimen collection swab. Do not touch the soft tip or lay the swab down. If you touch the soft tip, use a new APTIMA Combo 2 Unisex Swab Collection Kit.
- Carefully insert the blue-shaft swab into the vagina about 2 inches (5 cm) past the introitus and gently rotate the swab for 10 to 30 seconds.
- Make sure the swab touches the walls of the vagina so that moisture is absorbed by the swab and then withdraw the swab without touching the skin.
- Align: Remove the cap from the Aptima Unisex Swab Media Tube and immediately place the swab into the transport tube so that the score line is at the top of the tube.
- Break: Carefully break the swab shaft at the score line against the side of the tube.
- Close: Tightly recap the Aptima Swab. The specimen is now ready for transport. Discard the top portion of the swab. Label the sample tube with two patient identifiers and place it with a laboratory requisition in a specimen bag, transport and store 2°C to 30°C for up to 60 days of collection.
C: Endocervical swab – Clinician collection (using Aptima Unisex Swab Kit)
- Note expiry date on sample collection vial. Do not use expired vials.
- Clean: Remove excess mucus from the cervical ostium and surrounding mucosa using the cleaning swab (white-shaft swab in the package with red printing). Discard this swab. Note: Cleaning excess mucus from the cervical os is required to ensure an adequate sample is obtained for processing.
- Collect: Insert the specimen collection swab (blue-shaft swab in the package with the green printing) into the endocervical canal. Gently rotate the swab clockwise for 10 to 30 seconds in the endocervical canal to ensure adequate sampling.
- Withdraw the swab carefully; avoid any contact with the vaginal mucosa.
- Align: Remove the cap from the Aptima Unisex Swab Media Tube and immediately place the swab into the transport tube so that the score line is at the top of the tube.
- Break: Carefully break the swab shaft at the score line against the side of the tube.
- Close: Tightly recap the Aptima Swab. The specimen is now ready for transport. Discard the top portion of the swab. Label the sample tube with two patient identifiers and place it with a laboratory requisition in a specimen bag, transport and store 2°C to 30°C for up to 60 days of collection.
D: Endocervical ThinPrep using Plastic Spatula and Brush
- Note expiry date on sample collection vial. Do not use expired vials.
- If lubrication of the speculum is required, please use warm water. The use of lubricant may interfere with pathology tests. However, if necessary a small amount of water- soluble carbomer-free lubricant should be applied sparingly to the outer portion of the speculum only, avoiding the tip.
- Obtain an adequate sample from the ectocervix using a plastic spatula. Select the contoured end of the plastic spatula and rotate it 360º in a clockwise direction around the entire ectocervix, while maintaining tight contact with ectocervical
- Rinse the plastic spatula immediately into the vial by swirling the spatula vigorously in the vial 10 times. Discard the plastic spatula.
- Obtain an adequate sampling from the endocervix using an endocervical brush device. Insert the Cytobrush into the endocervical canal until only the bottom-most bristles are exposed. Slowly rotate 1/4 or 1/2 turn in one direction. Do not over-rotate the brush.
- Rinse the endocervical brush immediately in the same vial by rotating the device in the solution 10 times while pushing it against the vial wall. As a final step, swirls the brush vigorously to further release material. Discard the the brush.
- Tighten the cap so that the torque line on the cap passes the torque line on the vial. Do not over-tighten. Label the vial with two patient identifiers, place the vial and pathology request form in a specimen bag, transport and store 2°C to 30°C for up to 1 year of collection.
E: Cervical ThinPrep using a Broom-like device
- Note expiry date on sample collection vial. Do not use expired vials.
- If lubrication of the speculum is required, please use warm water. The use of lubricant may interfere with pathology tests. However, if necessary a small amount of water- soluble carbomer-free lubricant should be applied sparingly to the outer portion of the speculum only, avoiding the tip.
- Obtain an adequate sample from the transformation zone of the cervix using a cervical sampler (broom-like device). Insert the central bristles of the broom into the endocervical canal deep enough to allow the shorter bristles to fully contact the ectocervix. Push gently, and rotate the brush 360° in a clockwise direction 3–5 times.
- Rinse the cervical sampler immediately into the vial by pushing it into the bottom of the vial 10 times, forcing the bristles apart. As a final step, swirls the brush vigorously to further release material. Visually inspect the cervical sampler to ensure that no material remains attached. Discard the collection device. Do not leave the head of the cervical sampler in the vial.
- Tighten the cap so that the torque line on the cap passes the torque line on the vial. Do not over-tighten. Label the vial with two patient identifiers, place the vial and pathology request form in a specimen bag, transport and store 2°C to 30°C for up to 1 year of collection.
Special Patient Preparation
A: Urine Collection
- Patients should not have urinated for at least one hour prior to specimen
- Female patients should not cleanse the labial area prior to collecting
- If the collected urine contains excess blood (specimen has a dark red or brown color) it should be discarded and not used for testing.
Unacceptable Specimen Conditions
Urine specimens with more than 24 hours of collected without transferred to cobas PCR media. Urine specimen with volume under or above the black lines, specimen contains excess of blood (has a dark red or brown color), expired collection and transport vials, specimens contains excess of mucous, swab specimens without Dacron or Flock swab inside.
Insurance Pre-Authorization Required
Not required.
