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Particle agglutination tests are laboratory procedures used to assess the presence and levels of specific antibodies in a patient's blood. These tests play a crucial role in evaluating infection status and identifying various viral and bacterial infections. For instance, they can be utilized to detect infections caused by the measles virus, streptococcal bacteria, or Treponema pallidum, which is responsible for syphilis. The CPT® Code 86406 specifically refers to the titer measurement of each antibody following a positive screening result. This means that if an initial screening test indicates the presence of an antibody, the titer test is performed to quantify the level of that antibody in the serum or plasma. The process begins with obtaining a blood sample through a venipuncture, which is a separate reportable procedure. The serum or plasma is then subjected to various testing methods, including semiquantitative hemagglutination, fluorescent enzyme assays, and light flow cytometry, to accurately determine the antibody titer levels.
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Particle agglutination tests are indicated for the evaluation of infection status and the identification of specific viral and bacterial pathogens. The following conditions may warrant the use of this testing method:
The procedure for conducting a particle agglutination test involves several key steps to ensure accurate results. First, a blood sample is obtained from the patient through a venipuncture, which is a separate and reportable procedure. This step is critical as it provides the serum or plasma needed for testing. Once the blood sample is collected, it is processed to separate the serum or plasma from the cellular components. The next step involves testing the serum or plasma using various methods to detect the presence of antibodies. These methods may include semiquantitative hemagglutination, where particles agglutinate in the presence of specific antibodies, fluorescent enzyme assays that utilize fluorescent markers to identify antibodies, and light flow cytometry, which measures the light scattered by particles in a fluid stream to quantify antibody levels. If the initial screening test is positive, the titer levels for each antibody are then reported using CPT® Code 86406, providing a quantitative measure of the antibody concentration in the sample.
After the particle agglutination test is completed, the results are analyzed and reported to the healthcare provider. Depending on the findings, further clinical evaluation may be necessary. If the titer levels indicate a significant presence of antibodies, this may suggest an active infection or a recent exposure to the pathogens tested. The healthcare provider will interpret the results in conjunction with the patient's clinical history and symptoms to determine the appropriate course of action, which may include additional testing, treatment, or monitoring. It is important for the patient to follow up with their healthcare provider to discuss the results and any necessary next steps.
| Short Descr | PARTICLE AGGLUT ANTBDY TITR | Medium Descr | PARTICLE AGGLUTINATION TITER EACH ANTIBODY | Long Descr | Particle agglutination; titer, each antibody | 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 | 2 | CCS Clinical Classification | 235 - Other Laboratory |
| 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. | 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. | GZ | Item or service expected to be denied as not reasonable and necessary |
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| 2013-01-01 | Changed | Short Descriptor changed. |
| 1995-01-01 | Added | First appearance in code book in 1995. |
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