PrEP Use Only: Chlamydia/Gonococcus, Pharyngeal Swab, NAA

CPT: 87491; 87591
87491; 8759187491; 87591
87491; 8759187491; 87591
Updated on 06/9/2024
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  • Pre-exposure prophylaxis screening for Ct/GC, Pharyngeal Source

Special Instructions

Submit one specimen per test requested. Specify the exact specimen source/origin (e.g., pharyngeal). Indicate a specific test number on the test request form.

Expected Turnaround Time

2 - 3 days

Related Documents

Specimen Requirements


Pharyngeal specimen collected with Aptima® Unisex collection swab and submitted in the Aptima® swab specimen transport tube


1 swab (pharyngeal)

Minimum Volume

1 swab (pharyngeal)


Aptima® swab specimen transport tube


Use the blue-shafted swab, labeled "unisex collection swab for endocervical and male urethral specimens," to rub the posterior pharynx and tonsillar areas. Do not use the white-shafted swab; discard this swab. 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 at the scoreline; use care to avoid splashing of the contents. Recap the swab specimen transport tube tightly.

Storage Instructions

Maintain specimen at room temperature or refrigerate (2°C to 30°C).

Causes for Rejection

Inappropriate transport conditions; bacterial swabs; swabs from sites other than pharyngeal; unlabeled specimens or those with a discrepancy between the specimen label and the test request form; Aptima swab transport tube with no swab, two swabs or swab not supplied by Hologic; Aptima swabs greater than 60 days from collection; any transport device other than an Aptima swab transport

Test Details


This test is used for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae in patients who are eligible for or who are receiving pre-exposure prophylaxis for HIV (PrEP).


Nucleic acid amplification (NAA)


Kent CK, Chaw JK, Wong W, et al. Prevalence of rectal, urethral, and pharyngeal Chlamydia and gonorrhea detected in 2 clinical settings among men who have sex with men: San Francisco, Calif, 2003. Clin Infect Dis. 2005 Jul 1;41(1):67-74.15937765


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
188710 PrEP: Ct/GC NAA, Pharyngeal 188610 C. trachomatis, NAA, Pharyn 57288-3
188710 PrEP: Ct/GC NAA, Pharyngeal 188634 N. gonorrhoeae, NAA, Pharyn 57289-1
188710 PrEP: Ct/GC NAA, Pharyngeal 019054 PDF N/A

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