Question 2. Which specimen types are suitable for CT and NG, RNA, transcription-mediated amplification (TMA), urogenital tests (test codes 11361, 11362, 11363)?

The following specimen types are suitable: Vaginal, Endocervical or Urethral using Aptima® Multitest or Unisex Collection Kit First catch urine in Aptima® Urine Collection Kit Liquid cytology (PreservCyt®) preservative (ThinPrep®) in Aptima® Transfer Tube SurePath™ preservative fluid in Aptima® Transfer Tube

Question 3. Which extragenital specimen types are suitable for CT and NG TMA?

Rectal swabs in Aptima® Transport Tube3 are suitable for the following tests: N gonorrhoeae, RNA, TMA rectal (test code 16504) C trachomatis, RNA, TMA rectal (test code 16505) N. gonorrhoeae/C. trachomatis, RNA, TMA rectal (test code 16506) Throat (pharyngeal) swab in Aptima® Transport Tube3 are suitable for the following tests: C trachomatis, RNA, TMA throat (test code 70048) N gonorrhoeae, RNA, TMA throat (test code 70049) N gonorrhoeae/C. trachomatis, RNA, TMA throat (test code 70051) Conjunctiva swab using Aptima® Multi-test Collection kit, Aptima® Unisex Collection kit or Universal Transport Medium are suitable for the following test: Chlamydia trachomatis/Neisseria gonorrhoeae, TMA (test code 13525)

Chlamydia trachomatis/Neisseria gonorrhoeae RNA, TMA

Test codes: 11361, 11362, 11363; 16504, 16505, 16506; 70048, 70049, 70051

According to the Centers for Disease Control (CDC), sexually active women 24 years old or younger should be screened for urogenital CT/NG.¹ Women and men who have suspected exposure, are at high risk for sexually transmitted infections (STIs), or have symptoms of an STI should also receive urogenital CT/NG testing.¹

The collection and testing of extragenital (rectal and throat) specimens for CT/NG should be directed by symptoms at these sites, sexual history, and potential or known exposures.¹

The following specimen types are suitable:

Vaginal, Endocervical or Urethral using Aptima^® Multitest or Unisex Collection Kit
First catch urine in Aptima^® Urine Collection Kit
Liquid cytology (PreservCyt^®) preservative (ThinPrep^®) in Aptima^® Transfer Tube
SurePath™ preservative fluid in Aptima^® Transfer Tube

Rectal swabs in Aptima^® Transport Tube³ are suitable for the following tests:

N gonorrhoeae, RNA, TMA rectal (test code 16504)
C trachomatis, RNA, TMA rectal (test code 16505)
N. gonorrhoeae/C. trachomatis, RNA, TMA rectal (test code 16506)

Throat (pharyngeal) swab in Aptima^® Transport Tube³ are suitable for the following tests:

C trachomatis, RNA, TMA throat (test code 70048)
N gonorrhoeae, RNA, TMA throat (test code 70049)
N gonorrhoeae/C. trachomatis, RNA, TMA throat (test code 70051)

Conjunctiva swab using Aptima^®Multi-test Collection kit, Aptima^®Unisex Collection kit or Universal Transport Medium are suitable for the following test:

Chlamydia trachomatis/Neisseria gonorrhoeae, TMA (test code 13525)

Repeat testing of the same positive sample using the same methodology is not recommended for most populations and does not improve the positive predictive value when screening with currently available nucleic acid amplification tests (NAATs).⁴ In rare circumstances, confirmatory testing can be considered, eg, when a false-positive CT or NG NAAT result is expected to have adverse medical, social, or psychological consequences, or in low-prevalence settings, where the positive predictive value (likelihood that a positive result is a true positive) is reduced.⁴ In these cases, the following tests target alternative nucleic acid regions and can thus be used to confirm positive CT or NG NAAT screening test results:

Chlamydia trachomatis RNA, TMA, Alternate Target (test code 15031)
Chlamydia trachomatis RNA, TMA, Alternate Target, Rectal (test code 91046)
Neisseria gonorrhoeae RNA, TMA, Alternate Target (test code 15033)
Neisseria gonorrhoeae RNA, TMA, Alternate Target, Rectal (test code 90990)

Per the Centers for Disease Control guidelines, non-pregnant women should be retested approximately 3 months after treatment due to high re-infection rates.¹

Test-of-cure for therapeutic failure is not recommended for non-pregnant women unless symptoms persist and should not be performed earlier than 4 weeks post-treatment due to continued presence of nonviable organisms.¹ Pregnant women should receive a test-of-cure 4 weeks after treatment and be retested again 3 months after treatment.¹

References

Workowski KA, Bachmann LH, Chan PA, et al. Sexually transmitted infections treatment guidelines, 2021. MMWR Recomm Rep. 2021;70(4):1-187.
Gaydos CA, Quinn TC, Willis D, et al. Performance of the APTIMA Combo 2 assay for detection of Chlamydia trachomatis and Neisseria gonorrhoeae in female urine and endocervical swab specimens. J Clin Microbiol. 2003;41(1):304-309.
Van der Pool B, Chernesky M, Gaydos G, et al. Multicenter comparison of nucleic acid amplification tests for the diagnosis of rectal and oropharyngeal chlamydia trachomatis and neisseria gonorrhoeae infections. J Clin Microbiol. 2022;60(1):e0136321.
Laboratory diagnostic testing for Chlamydia trachomatis and Neisseria gonorrhoeae. Expert Consultation Meeting summary report. January 13-15, 2009. Atlanta, GA. http://www.aphl.org/aphlprograms/infectious/std/Documents/ID_2009Jan_CTGCLab-Guidelines-Meeting-Report.pdf. Accessed June 20, 2014.

This FAQ is provided for informational purposes only and is not intended as medical advice. A physician’s test selection and interpretation, diagnosis, and patient management decisions should be based on the physician’s education, clinical expertise, and assessment of the patient.

Document FAQS.154 Version: 2

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Version 1: effective 02/29/2016 to 04/19/2024
Version 0: effective 12/05/2014 to 02/28/2016

Chlamydia trachomatis/Neisseria gonorrhoeae RNA, TMA

add Question 1. Who should be tested for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG)?

add Question 2. Which specimen types are suitable for CT and NG, RNA, transcription-mediated amplification (TMA), urogenital tests (test codes 11361, 11362, 11363)?

add Question 3. Which extragenital specimen types are suitable for CT and NG TMA?

add Question 4. Should repeat testing be used to confirm a positive CT or NG TMA screening test?

add Question 5. For patients who test positive for CT or NG, how long after treatment should they wait before retesting?