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CT/GC
CHLAMYDIA TRACHOMATIS AND NEISSERIA GONORRHOEAE DETECTION BY NUCLEIC ACID AMPLIFICATION

Test Code CT/GC 
Test CHLAMYDIA TRACHOMATIS AND NEISSERIA GONORRHOEAE DETECTION BY NUCLEIC ACID AMPLIFICATION 
Methodology cobas® 4800 CT/NG Test by Polymerase Chain Reaction (PCR) 
Specimen SUBMIT ONLY 1 OF THE FOLLOWING SPECIMENS

URINE
1. Patient must not have urinated for at least 2 hours prior to sampling.
2. Collect 10 - 50 mL of first catch urine (first part of the stream) in a sterile container without preservatives.
3. Seal the container and label according to policy.
4. Refrigerate the specimen. Cause for rejection: urine stored longer than 24 hours at ambient temperature.
5. Transport promptly. Specimen should be received in the laboratory the same day as collected for transfer to a cobas® PCR Media tube.

NOTE: Urine specimens are accepted for both males and females. According to the MMWR( March 14, 2014), the sensitivity of detecting CT/GC infections by any NAAT test can be up to 10% lower in a female urine specimens compared to a vaginal or endocervical swab, while the specificity is the same. For female patients, a vaginal swab is the preferred specimen.


VAGINAL SWAB (Preferred Female Specimen): CT-GC Swab Collection

Collect using the cobas® PCR Sample Collection Kit, supplied by NorDx, as follows:
1. Insert dry swab into vagina (do not pre-wet in PCR media) and rotate swab for 30 seconds to ensure adequate sampling.
2. Transfer swab to the tube of cobas® PCR Medium and break swab into the tube at the scored black line on the shaft.
3. Leave swab in the transport medium and replace the tube cap securely to prevent leaking. (Cause for rejection: receipt of transport medium with no swab.)
4. Label the transport tube according to policy and transport to the lab for testing.
**SPECIMEN SOURCE IS REQUIRED ON REQUEST FORM FOR PROCESSING**.
5. Collected specimen swab is stable at 2°C to 30°C for 90 days.

ENDOCERVIX (Alternate Female Specimen)

Collect using the cobas® PCR Sample Collection Kit, supplied by NorDx, as follows:
1. Remove excess mucus from the exocervix using one of the swabs provided in the collection kit and DISCARD this swab. (Cause for rejection: cervical mucus present in specimen)
2. Insert the second swab into the endocervix and rotate for 15 - 30 seconds to ensure adequate sampling.
3. Transfer swab to the tube of cobas® PCR Medium and break swab into the tube at the scored black line on the shaft.
4. Leave swab in the transport medium and replace the tube cap securely to prevent leaking. (Cause for rejection: receipt of transport medium with no swab.)
5. Label the transport tube according to policy and transport to the lab for testing.
**SPECIMEN SOURCE IS REQUIRED ON REQUEST FORM FOR PROCESSING**.
6. Collected specimen swab is stable at 2°C to 30°C for 90 days.


NOTE:
• Vaginal swab is the optimal female specimen type for this assay. Use of other specimen types such as First-catch Urine, ThinPrep vial, or M-4 endocervical samples may reduce assay sensitivity.
• Replens® lubricant, spermicidal agents and feminine powder sprays may interfere with the assay lead to a result of INVALID. These products should not be used prior to specimen collection.


OTHER ACCEPTABLE SPECIMENS INCLUDE:
Endocervical swab in M-4 transport media, BD ProbeTec swab, Thinprep vial. These specimen types are not FDA-Approved and assay sensitivity may be affected.

**This test has been approved by the U.S. Food and Drug Administration (FDA) for use with the following specimen types: 1) self-collected vaginal swabs collected with a cobas PCR Female Swab Sample kit in a clinical setting, 2) male urine specimens that have been stabilized in cobas PCR media within 24 hours of collection. Use of other specimen types may adversely affect assay performance. 

Reference Values Negative for Chlamydia trachomatis
Negative for Neisseria gonorrhoeae
If positive, reported as positive for Chlamydia trachomatis DNA or positive for Neisseria gonorrhoeae DNA. 
Analytic Time 1 Day; Maximum Laboratory Time - 4 Days 
Day(s) Test Set Up 3 times per week 
CPT Code(s) 87491  Chlamydia
87591  Gonorrhoeae