2025 CPT code 83520
(Active) Effective Date: N/A Laboratory - Chemistry Procedures Pathology and Laboratory Feed
Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; quantitative, not otherwise specified.
Modifiers may be applicable to further specify the circumstances of the service. For example, modifier 59 may be used to indicate a distinct procedural service.
Medical necessity must be established by the ordering physician and should be documented in the patient's medical record. The documentation should demonstrate a clear link between the test ordered (83520) and the patient's signs, symptoms, or diagnosis.
The laboratory analyst performs the technical steps to quantitate the noninfectious antigen or noninfectious antibody from any specimen type.
In simple words: This test measures the amount of a specific substance in a sample of your bodily fluid, like blood or urine, using a method called immunoassay. It's used when there's no other specific test for the substance being measured.
This code describes a quantitative immunoassay for an analyte that is not an infectious agent antibody or infectious agent antigen.It is used when other specific analyte or method-specific codes are unavailable within the Chemistry (82009-84830) subsection.
Example 1: A patient presents with symptoms suggestive of an autoimmune disorder.A physician orders an immunoassay for a specific autoantibody not otherwise specified in CPT, and 83520 is reported., A patient with a history of cancer is being monitored for recurrence. A physician orders a quantitative immunoassay for a tumor marker not listed elsewhere in CPT, and the lab reports 83520., A research study requires the measurement of a novel protein biomarker in patient serum samples.As this analyte does not have a specific CPT code, 83520 is used for billing.
Documentation should include the specific analyte being measured, the specimen source, the quantitative result, the reason for the test, and the clinical indication.
- Payment Status: Active
- Specialties:Pathology, various clinical specialties (depending on the analyte being measured)
- Place of Service:Independent Laboratory, Hospital Laboratory, Physician Office Laboratory