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Official Description

Antibody; bacterium, not elsewhere specified

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 86609 refers to the testing of antibodies against bacteria that are not specifically categorized under other codes. This procedure involves analyzing a blood sample to detect the presence of antibodies, which are proteins produced by the immune system in response to infections. The common language description highlights that this code encompasses tests for various bacteria, including but not limited to listeria, mycobacterium tuberculosis, and the toxic shock syndrome antibody. These tests are particularly relevant for patients who experience chronic or recurrent infections, as they help identify underlying bacterial causes that may not be covered by more specific codes. The methodology for testing varies based on the specific antibody being assessed; for instance, listeria is typically tested using complement fixation, while mycobacterium tuberculosis is evaluated through enzyme-linked immunosorbent assay (ELISA), and toxic shock syndrome is assessed using multi-analyte immunodetection (MAID). The immunoglobulin G (IgG) class of antibodies is the most frequently tested, although other classes such as IgM may also be included. Importantly, this code can be reported multiple times, reflecting the number of different organisms tested, the various antibody classes analyzed, and the distinct methodologies employed for each organism.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 86609 is indicated for the testing of antibodies in patients who may be experiencing infections caused by bacteria that are not specifically classified under other CPT® codes. The following conditions and scenarios may warrant the use of this code:

  • Chronic Infections Patients with ongoing or recurrent infections that require further investigation to identify potential bacterial causes.
  • Recurrent Infections Individuals who experience repeated episodes of infection, necessitating a comprehensive evaluation of their immune response to various bacterial pathogens.
  • Suspected Bacterial Infections Cases where there is a clinical suspicion of infection by bacteria such as listeria, mycobacterium tuberculosis, or those associated with toxic shock syndrome.

2. Procedure

The procedure associated with CPT® Code 86609 involves several key steps to ensure accurate testing for antibodies against unspecified bacteria. The following procedural steps are typically followed:

  • Step 1: Sample Collection A blood sample is collected from the patient, which serves as the specimen for antibody testing. Proper collection techniques are essential to avoid contamination and ensure the integrity of the sample.
  • Step 2: Sample Preparation The collected blood sample is processed to separate the serum, which contains the antibodies. This may involve centrifugation to separate the components of the blood effectively.
  • Step 3: Antibody Testing The specific methodology for testing is selected based on the bacteria of interest. For instance, complement fixation may be used for listeria, ELISA for mycobacterium tuberculosis, and MAID for toxic shock syndrome. Each method is designed to detect the presence of antibodies in the serum.
  • Step 4: Result Interpretation After the testing is completed, the results are analyzed to determine the presence and levels of antibodies. This information is crucial for diagnosing potential bacterial infections and guiding further clinical decisions.
  • Step 5: Reporting The results are compiled into a report that is provided to the healthcare provider. This report may include quantitative or qualitative results, depending on the testing methodology used.

3. Post-Procedure

Post-procedure care for patients undergoing testing with CPT® Code 86609 typically involves monitoring for any adverse reactions to the blood draw, although such reactions are rare. Patients may be advised to follow up with their healthcare provider to discuss the results of the antibody tests. Depending on the findings, further diagnostic testing or treatment may be necessary. It is also important for healthcare providers to consider the clinical context of the results, as the presence of antibodies may indicate past exposure or current infection, necessitating additional evaluation or intervention.

Short Descr BACTERIUM ANTIBODY
Medium Descr ANTIBODY BACTERIUM NOT ELSEWHERE SPECIFIED
Long Descr Antibody; bacterium, not elsewhere specified
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 14
CCS Clinical Classification 235 - Other Laboratory
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.
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.
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.
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GA Waiver of liability statement issued as required by payer policy, individual case
GW Service not related to the hospice patient's terminal condition
Date
Action
Notes
1993-01-01 Added First appearance in code book in 1993.
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