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Official Description

Infectious agent detection by nucleic acid (DNA or RNA); Chlamydia trachomatis, amplified probe technique

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 87491 refers to the detection of the infectious agent Chlamydia trachomatis through nucleic acid techniques, specifically utilizing an amplified probe technique. This method is crucial for identifying infections caused by Chlamydia trachomatis, which is a common sexually transmitted disease (STD). The amplified probe technique enhances the sensitivity of the test, allowing for the detection of Chlamydia nucleic acids, which may be present in low quantities in the specimen. This is particularly important as Chlamydia infections often do not present noticeable symptoms, especially in women, leading to potential long-term complications such as infertility if left untreated. In men, while symptoms such as burning and itching of the urethra may occur, they typically do not experience the same level of reproductive damage. The testing process involves collecting a specimen using a swab from areas such as the cervix, male urethra, or eye, and the methodology can vary depending on the test kit used. The amplified probe technique, such as polymerase chain reaction (PCR), is employed to create multiple copies of the Chlamydia nucleic acids, ensuring accurate detection even when the organism is present in low levels. This procedure is vital for timely diagnosis and treatment, thereby reducing the risk of complications associated with untreated Chlamydia infections.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure associated with CPT® Code 87491 is indicated for the detection of Chlamydia trachomatis infections. The following conditions and symptoms may warrant the use of this test:

  • Asymptomatic Infection Chlamydia trachomatis infections often present without symptoms, particularly in women, making screening essential for early detection.
  • Symptoms of Urethritis In men, symptoms such as burning and itching of the urethra may indicate a potential Chlamydia infection, prompting the need for testing.
  • Risk of Infertility Women with suspected Chlamydia infections may be tested to prevent complications such as pelvic inflammatory disease (PID) and infertility.
  • Sexually Active Individuals Routine screening is recommended for sexually active individuals, especially those with multiple partners or those who do not consistently use barrier protection.

2. Procedure

The procedure for CPT® Code 87491 involves several key steps to ensure accurate detection of Chlamydia trachomatis nucleic acids:

  • Specimen Collection A specimen is collected using a swab from the cervix in females, the male urethra, or the eye in cases of conjunctivitis. Proper collection techniques are essential to obtain a viable sample for testing.
  • Preparation of the Specimen The collected specimen is prepared for testing, which may involve lysing cells to release nucleic acids. This step is crucial for ensuring that the nucleic acids from the Chlamydia organism are available for detection.
  • Amplification of Nucleic Acids An amplification technique, such as polymerase chain reaction (PCR), is employed to create multiple copies of the Chlamydia nucleic acids. This amplification is particularly important when the initial sample may contain low levels of the target microorganism.
  • Detection of Nucleic Acids Following amplification, various techniques are used to detect the presence of the Chlamydia nucleic acids. This may involve hybridization methods that allow for the identification of the specific nucleic acid sequences associated with Chlamydia trachomatis.

3. Post-Procedure

After the procedure associated with CPT® Code 87491, the following post-procedure considerations are important:

Results from the nucleic acid detection test are typically available within a short timeframe, allowing for prompt diagnosis and treatment. If the test is positive, appropriate antibiotic therapy should be initiated to treat the Chlamydia infection. Patients should be counseled on the importance of notifying sexual partners and the need for follow-up testing to ensure the infection has been effectively treated. Additionally, individuals may be advised on preventive measures to reduce the risk of future infections, including safe sex practices and regular screenings, especially for those at higher risk.

Short Descr CHLMYD TRACH DNA AMP PROBE
Medium Descr IADNA CHLAMYDIA TRACHOMATIS AMPLIFIED PROBE TQ
Long Descr Infectious agent detection by nucleic acid (DNA or RNA); Chlamydia trachomatis, amplified probe technique
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 3
CCS Clinical Classification 206 - Microscopic examination (bacterial smear, culture, toxicology)
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GA Waiver of liability statement issued as required by payer policy, individual case
GW Service not related to the hospice patient's terminal condition
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
GZ Item or service expected to be denied as not reasonable and necessary
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Q4 Service for ordering/referring physician qualifies as a service exemption
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
X5 Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
FP Service provided as part of family planning program
33 Preventive services: when the primary purpose of the service is the delivery of an evidence based service in accordance with a us preventive services task force a or b rating in effect and other preventive services identified in preventive services mandates (legislative or regulatory), the service may be identified by adding 33 to the procedure. for separately reported services specifically identified as preventive, the modifier should not be used.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
GC This service has been performed in part by a resident under the direction of a teaching physician
KX Requirements specified in the medical policy have been met
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
QJ Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b)
QW Clia waived test
U6 Medicaid level of care 6, as defined by each state
XE Separate encounter, a service that is distinct because it occurred during a separate encounter
Date
Action
Notes
2022-01-01 Note Short description changed.
2011-01-01 Changed Short description changed.
1998-01-01 Added First appearance in code book in 1998.
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