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CHLAMYDIA TRACHOMATIS MOLECULAR DETECTION (TMA)

Item Value
Available Stat? No
Performed by? San Francisco Dept. of Public Health (SFDPH) Public Health Laboratory (PHL)
Test not performed by SFGH Clinical Laboratory
Principle The APTIMA(R) Transcription Mediated Amplification (TMA) Assay for chlamydia and gonorrhea is a sensitive and specific FDA-approved assay for the detection of Neisseria gonorrhoeae and Chlamydia trachomatis infection for the following specimen sources: endocervical, vaginal, male urethral, and urine.

In addition, the San Francisco Public Health Laboratory has validated this assay for the detection of N. gonorrhoeae and C. trachomatis in pharyngeal and rectal sources. Conjunctival, or any other sources, are not validated for this assay, and cannot be tested. The assay detects the presence of ribosomal RNA (rRNA) of N. gonorrhoeae and C. trachomatis in patient samples, negating the need for culture methods.
Method Gen-Probe APTIMA(R) Transcription Mediated Amplification (TMA)

Container type Materials for specimen collection, and acceptable specimen sources:

APTIMA(R) Unisex Swab Collection Kit (White shaft swab for cleaning endocervix/Blue shaft swab for collecting sample): for endocervical, male urethral, rectal, and pharyngeal sources

APTIMA(R) Urine Collection Kit (disposable pipette, urine transport tube): for urine specimens

APTIMA(R) Vaginal Swab Collection Kit (Pink shaft swab): for vaginal sources
Collection Instructions Urine specimens: Transfer, at the clinic, within 24 hours of urine collection using the disposable pipette provided in the APTIMA(R) urine kit, the first-catch urine specimen from a urine collection cup to an APTIMA(R) urine transport tube bringing the final volume in the APTIMA tube to within the marked fill area. Tightly re-cap the APTIMA urine transport tube, and make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number). Urine specimens properly transferred to a urine APTIMA transport tube within 24 hours of urine collection can be stored at 2°C to 30°C for up to 30 days before being submitted to the laboratory.

Endocervical swab specimens: Using the APTIMA(R) Unisex Swab Collection Kit, remove excess mucus from the cervical os and surrounding mucosa with the cleaning swab (white shaft swab). Discard this swab. Insert the cervical specimen collection device (blue shaft swab) into the endocervical canal. Rotate the device clockwise three full turns to ensure adequate sampling. Withdraw the device carefully; avoid any contact with the vaginal mucosa. Remove the cap from the unisex specimen transport tube and immediately place the specimen collection device into the transport tube. Break the swab shaft at the scoreline, and recap the tube, leaving the lower half of the blue swab in the tube. Use care to avoid spilling of contents. Make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number), and specimen source. After collection, cervical specimens can be stored at 2°C to 30°C for 60 days until tested.

Male urethral swab specimens: The patient should not have urinated for at least 1 hour prior to sample collection. Using the APTIMA(R) Unisex Swab Collection Kit, insert the specimen collection swab (blue shaft swab) 2 to 4 cm into the urethra. Gently rotate the swab clockwise for 2 to 3 seconds in the urethra to ensure adequate sampling. Withdraw the swab carefully. Remove the cap from the swab specimen transport tube and immediately place the specimen collection swab into the transport tube. Carefully break the swab shaft against the side of the tube at the scoreline and discard the top portion of the swab shaft; use care to avoid splashing of contents. Re-cap the swab specimen transport tube tightly and make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number), and specimen source. After collection, male urethral specimens can be stored at 2°C to 30°C for up to 60 days until tested.

Vaginal swab specimens: Peel open the APTIMA(R) Vaginal Swab Collection Kit. Remove the swab (pink shaft swab). Carefully insert the 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. While holding the swab in the same hand, unscrew the cap from the tube. Do not spill the contents of the tube. Immediately place the swab into the transport tube so that the score line is at the top of the tube. Carefully break the swab shaft at the score line against the side of the tube. Discard the top portion of the swab shaft. Tightly screw the cap onto the tube, and make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number). After collection, vaginal specimens can be stored at 2°C to 30°C for up to 60 days until tested.

Rectal swab specimens: From the APTIMA(R) Unisex Swab Collection Kit, use only the blue shaft specimen collection swab for specimen collection. Do not use the white cleaning swab for specimen collection. For asymptomatic collection: moisten the swab with sterile saline and insert into the anus and rectum - leave for 20 seconds. For symptomatic collection: swab rectal mucosa using a sterile anoscope. Remove the cap from the swab specimen transport tube and immediately place the specimen collection swab into the transport tube. Carefully break the swab shaft against the side of the tube at the scoreline and discard the top portion of the swab shaft. Use care to avoid spilling of contents. Re-cap the swab specimen transport tube tightly and make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number), and specimen source. After collection, rectal specimens can be stored at 2°C to 30°C for up to 60 days until tested.

Pharyngeal (throat) swab specimens: From the APTIMA(R) Unisex Swab Collection Kit, use only the blue shaft specimen collection swab for specimen collection. Do not use the white cleaning swab for specimen collection. Swab the area between the tonsillar pillars and the region posterior to the pillars. Remove the cap from the swab specimen transport tube and immediately place the specimen collection swab into the transport tube. Carefully break the swab shaft against the side of the tube at the scoreline and discard the top portion of the swab shaft. Use care to avoid spilling of contents. Re-cap the swab specimen transport tube tightly and make sure the specimen is labeled with the following required information: first and last name of patient (or patient medical record number), and specimen source. After collection, pharyngeal specimens can be stored at 2°C to 30°C for up to 60 days until tested.
Sample type Urine, male urethra, female endocervical, rectal, pharyngeal or vaginal.
Special instructions Testing for Chlamydia trachomatis by nucleic acid amplification is performed by the San Francisco Department of Public Health (SFDPH). Specimens must be submitted with a SFDPH requisition. Use this link to a fillable .pdf of the correct requisition, for use by ZSFG inpatient locations:
http://sfcdcp.org/document.html?id=1094
Do NOT use a ZSFG Clinical Lab requisition for these test requests.
Properly labeled specimens, accompanied by an SFDPH requisition, can be brought to the ZSFG Clinical Laboratory for messenger transport to SFDPH.
Normal range Results are available in LCR, under Microbiology. Click on PHL Results.

Normal Range: Negative.

Synonyms Chlamydia Molecular Testing, Chlamydia NAAT
Stability Once specimens are placed into the APTIMA(R) collection tubes they can be stored and transported at room temperature (stable 2°C to 30°C for up to 30 days for urine specimens, 60 days for other specimen types).
Causes for rejection Please note that PHL will not call in the event that a test request must be cancelled for any of the following reasons:

Samples accompanied by incomplete requisition will be rejected for testing.

The patient identification must match between the specimen tube label and the test request form. Mismatches in identification between specimens and forms will not be tested.

The fluids that are contained within the APTIMA(R) transport tubes act as a preservative and a cell lysis buffer for specimens. Urine specimens with a final volume higher than the marked fill area could lead to reduced sensitivity upon testing, and will be rejected upon arrival to the laboratory.

Unprocessed urine specimens submitted in urine collection cups will always be rejected upon receipt.

APTIMA(R) swab transport tubes that do not have a swab in the tube upon receipt at the laboratory will not be processed. Swabs should remain in the tubes as indication of specimen collection (to prevent the likelihood producing false-negative results).

APTIMA swab transport tubes that contain the white cleaning swab provided in the kit upon receipt at the laboratory will not be processed. These swabs can damage the testing machine if left in the transport tube upon processing.

Do not puncture the foil caps of the APTIMA transport tubes. The machine that
processes these specimens punctures the foil cap upon testing. Specimen collection tubes received with punctured foil-caps can leak in transit, and will not be processed.
Turn around times The turn-around-time for specimen testing is 7 business days (Monday through Friday) from receipt; however, results can be made available within a shorter time period. To expedite testing, please contact the Public Health Laboratory directly: 415-554-2800.
Additional information Notes on results reporting:

Specimens resulted as "unsatisfactory" are the result of sometimes unknown qualities of a specimen that caused the testing machine to reject the specimen in duplicate. The most frequent causes of assay rejection by the machine, which lead to "unsatisfactory" results are: too low of volume in the APTIMA(R) transport tube, caused by a spilling or pouring out of fluid volume during specimen collection; and crystallized substances in urine specimens that we were unable to dissolve upon warming of specimens. Please recollect a specimen in these instances.

Specimens resulted as "inconclusive" were tested in duplicate, and were found to be inconclusive in the presence of chlamydia or gonorrhea ribosomal RNA. Please resubmit a specimen for testing.
Last Updated 4/6/2016 11:20:36 AM
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