2025 CPT code 86618

This code represents a qualitative or semiquantitative immunoassay for Borrelia burgdorferi antibodies, used to screen for Lyme disease.

Report one unit of 86618 for each immunoglobulin class (e.g., IgG, IgM) or for each species or type of Borrelia burgdorferi. Modifier 91 may be used to indicate repeat testing. Check with individual payers for specific billing guidelines.

Modifiers such as 91 (repeat clinical diagnostic laboratory test) or 59 (distinct procedural service) might apply depending upon payer and circumstances of testing.

Medical necessity for this test is established when there is clinical suspicion of Lyme disease based on symptoms, exposure history, and physical findings.Testing may also be indicated for monitoring treatment response in patients with confirmed Lyme disease.

The laboratory analyst performs the technical aspects of the test, including specimen handling, reagent preparation, analysis, and interpretation of results. The ordering clinician is responsible for integrating the test results with the patient's clinical picture and making treatment decisions.

IMPORTANT For a single-step method like a reagent strip, use 86318. For a quantitative test, use 86317.For confirmatory testing (e.g., Western Blot), use 86617.

In simple words: This test checks your blood or spinal fluid for signs of Lyme disease. It looks for substances your body makes to fight the bacteria that cause the disease. It is performed in multiple steps.

The test involves a multi-step process where a patient's blood or cerebrospinal fluid (CSF) is tested for antibodies against Borrelia burgdorferi, the bacterium that causes Lyme disease. The process typically includes reacting the specimen with test antigens, incubating the mixture, and adding an agent (such as a stain, fluorescent marker, etc.) to detect the antigen/antibody complex. The results are interpreted as positive, negative, or a semi-quantitative value.

Example 1: A patient presents with a bull's-eye rash and joint pain after a recent camping trip, raising suspicion for Lyme disease.Code 86618 is used for the initial antibody screening., A patient with neurological symptoms, such as facial palsy or meningitis, is being evaluated for neurologic Lyme disease.Code 86618 is used to detect Borrelia burgdorferi antibodies in cerebrospinal fluid., A patient previously treated for Lyme disease experiences recurring symptoms.Code 86618 may be used to monitor antibody levels and assess treatment response.

Documentation should include the reason for testing (e.g., clinical signs and symptoms, exposure history), the type of specimen collected (blood or CSF), the date of service, and the test results.

** Specimen collection codes (e.g., 36415 for venipuncture, 62270 for lumbar puncture) may be billed separately.

  • Revenue Code: T1H
  • Payment Status: Active
  • Specialties:Infectious Disease, Internal Medicine, Family Medicine, Pathology
  • Place of Service:Office, Independent Laboratory, Outpatient Hospital
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