DIAGNOSTIC TESTING for Chlamydia trachomatis and Neisseria gonorrhoeae

 

Immunologist               Claudia Rogers, BS MT (ASCP)               (307) 777-6061

Microbiologist                  Jody Fleming, BS MT (ASCP)               (307) 777-3609 

 

NUCLEIC ACID AMPLIFIED TESTING

Amplified nucleic acid probe technology is used for testing Chlamydia and Gonorrhea specimens. (See Bacteriology section for Gonorrhea cultures).  Specimens are submitted in a specific transport medium that lyses the organisms, exposing the nucleic acid to be tested.   Both organisms are tested on the same specimen.  Specimens to be tested include clinician-collected endocervical, vaginal, and male urethral swab specimens, and female and male urine specimens from both symptomatic and asymptomatic individuals.  The assay will detect nucleic acid of live, as well as dead organisms, and therefore should not be used as a test of cure.  However, in certain cases it may be necessary to retest previously positive individuals after 3-4 weeks, this testing is done only after consultation with the Immunologist.

 

Supplies
Collection kits are available from WPHL.  Use the WPHL Supply Order Form.  Download the form from the Forms page, complete all sections and FAX to the WPHL.  Do not order more kits than you can use within the dating period for each kit.  WPHL does not replace expired kits.

 

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) Testing

TYPE OF TEST

Nucleic acid amplification testing, NAAT, which detects both organisms on the same specimen. 

SPECIMEN REQUIREMENTS

Specimens must be collected in the appropriate APTIMA Combo 2 collection tube by Hologic Gen-Probe.  Refer to the Chlamydia Collection Protocol on this web site.  Follow the specific instructions for each sample type – female endocervical, vaginal and urine; male urethral and urine.  Accurate testing is directly related to adequate specimen collection.  Do not contaminate the outside and silver top of the specimen tube during collection.

Rectal and pharyngeal specimens are not FDA- approved for use with the APTIMA Combo 2 assay.  However, the WPHL has performed a validation study that meets CLIA requirements and demonstrates the APTIMA Combo 2 assay is acceptable for testing rectal and pharyngeal specimens at our facility using the blue unisex swab kit.

SHIPPING REQUIREMENTS

If using WPHL mailing containers, place the specimen in the biohazard bag with absorbent paper and put into the aluminum container.  Wrap the completed WPHL test request form around the outside of the aluminum container and insert this into the cardboard mailing container. 

If not using WPHL mailing containers, place the specimen in the biohazard bag with absorbent paper and insert the completed WPHL test request form into the outside pocket of the biohazard bag.  Then place into an approved shipping container.

Ship as diagnostic specimen following postal or carrier shipping regulations.

Female endocervical, vaginal, and male urethral specimens are stable at room temperature for 60 days.  Urines are stable for 30 days. 

DAYS TEST PERFORMED

Monday, Wednesday, and Friday.

RESULTS AVAILABLE

Results are mailed upon completion.  POSITIVE results are called to the submitter. 

REPORTING & INTERPRETATION

Chlamydia and Gonorrhoeae results are reported as NEGATIVE, POSITIVE, EQUIVACOL, or INCONCLUSIVE.  NEGATIVE results indicate no CT/GC detected.  POSITIVE results indicate organisms were detected and results will be differentiated as positive for CT, GC or both.  EQUIVACOL indicates the presence or absence of an organism was not clear.  This may be due to inadequate specimen collection, early stage of infection, or concurrent antibiotic therapy with residual organism still present.  A second specimen should be collected and resubmitted.  INCONCLUSIVE indicates testing was unable to determine presence or absence of organisms due to improper sampling.  For example, excess mucus may not have been removed with the white cleaning swab before collection of the specimen.  A second specimen should be collected and resubmitted.

ADDITIONAL COMMENTS

Collection protocol should be carefully reviewed to determine how and which type of tube to collect and submit based on collection site.

 

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