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Virology Laboratory

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) by molecular amplification - endocervical specimen

  • LIS Mnemonic: CTGCMA


    ENDOCERVICAL SWAB SPECIMEN - Obtain an APTIMA Combo 2 Assay Unisex Swab Specimen Collection Kit for Endocervical and Urethral Swab Specimens to collect patient specimens. Remove excess mucus from the

    Volume Required


    Minimum Required



    After specimen collection, transport the collection tube at room temperature.




    Use only the swabs and the specimen transport tubes contained in the APTIMA Combo 2 Assay Unisex Swab Specimen Collection Kit for Endocervical and Urethral Swab Specimens to collect patient specimens. Collection kits are available from Central Laboratory Services or the Clinical Virology Laboratory. Please carefully follow the instructions on the cover of the collection kit to obtain the desired specimen. For swab specimens, use only the unisex BLUE SHAFTED swab for specimen collection. The large tipped cleaning swab (WHITE SHAFT) should only be used to remove excess mucous from the cervical os and surrounding mucosa and should be discarded after use. Specimens not collected as instructed will be rejected.

    Unacceptable conditions

    Specimen not collected using an appropriate GenProbe APTIMA Combo 2 collection kit. Specimens not collected according to the defined collection instructions.

Days Performed

Mon, Wed, Fri



Reflex Testing

Test for Neisseria gonorrhoeae is performed in combination with the test for C. trachomatis. Positive results obtained for either C. trachomatis or N. gonorrhoeae when using the GenProbe APTIMA Combo 2 Assay will be confirmed using a second supplemental molecular amplification assay that detects a nucleic acid sequence different from that detected in the initial screening assay.


87801 (Combo) 87491 (CT supplemental) 87591 (GC supplemental)


The GenProbe APTIMA Combo 2 Assay uses transcription-mediated amplification (TMA) to replicate a specific region of the 23S rRNA from C. trachomatis and a specific region of the 16S rRNA from N. gonorrhoeae via DNA intermediates. A unique set of primers is used for each target molecule.

Disease Information


The GenProbe APTIMA Combo 2 Assay is designed to detect the presence of C. trachomatis and N. gonorrhoeae in clinician-collected endocervical, vaginal, and male urethral swab specimens, patient-collected vaginal swab specimens, and in female and male urine specimens. The assay is also intended for use with testing of gynecological specimens collected in the PreserCyt Solution and processed with the Cytyc ThinPrep 2000 System. The assay may be used to test specimens from symptomatic and asymptomatic individuals to aid in the diagnosis of gonococcal and/or chlamydial urogenital specimens. Alternative specimen sources such as conjunctival, nasopharyngeal and rectal specimens can also be tested using this assay for newborns or infants with suspected conjunctivitis and/or pneumonia due to infection with C. trachomatis during birth and for anorectal infections in women and men. Lastly, the test is applicable for the detection of C. trachomatis and/or N. gonorrhoeae in investigating sexual assault and abuse. Additional testing will be done to confirm any initial positive NAAT results in this patient population.


If positive, results are reported as Chlamydia trachomatis rRNA detected or Neisseria gonorrhoeae rRNA detected or both Chlamydia trachomatis rRNA and

Reference Values

Negative or no Chlamydia trachomatis rRNA detected. Negative or no Neisseria gonorrhoeae rRNA detec

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