Summary & Overview

CPT 86155: Neutrophil Chemotaxis Test

CPT code 86155 represents a laboratory test that measures neutrophil chemotaxis, assessing the ability of neutrophils to migrate toward inflammatory or infectious stimuli. This functional assay is used in clinical immunology to evaluate innate immune response and can inform diagnosis of neutrophil dysfunction or immune disorders. Nationally, such specialized laboratory tests are clinically important for guiding care in patients with recurrent infections or suspected immune defects.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication provides a concise overview of billing context, payer coverage considerations, clinical indications, and how the test is typically delivered in laboratory settings.

Readers will learn practical benchmarks and policy-relevant details for CPT code 86155, including common service settings, typical clinical context for ordering the test, and what to expect in terms of billing and coding presentation. Where available, payer-specific coverage patterns and reimbursement considerations are summarized. Data not available in the input are noted explicitly as such, and the content focuses on national applicability rather than state-level rules.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare86155CPTneutrophil chemotaxislaboratory testimmunologyclinical laboratorydiagnostic assay

Billing Code Overview

CPT code 86155 describes a laboratory technical procedure that evaluates neutrophil chemotaxis, the directed movement of neutrophils toward sites of inflammation or infection. The test is typically performed by a laboratory analyst on whole blood and assesses neutrophil function as part of immune response evaluation.

Service Type: Laboratory diagnostic test (technical component)

Typical Site of Service: Clinical laboratory or hospital laboratory

Clinical & Coding Specifications

Clinical Context

A 7-year-old child with recurrent, severe bacterial infections presents to a pediatric infectious disease clinic for immunologic evaluation. The clinician suspects a neutrophil functional disorder (e.g., congenital neutrophil chemotaxis defect or acquired dysfunction) after history of poor wound healing, recurrent skin and soft tissue infections, and abnormal complete blood count showing leukocytosis with neutrophilia. The clinic orders a neutrophil chemotaxis assay to assess directed migration of neutrophils toward chemotactic signals.

The clinical workflow: phlebotomy collects whole blood (or isolated neutrophils) per laboratory protocol; the specimen is transported to the specialized immunology or hematology laboratory. A laboratory analyst performs the technical assay to measure neutrophil chemotaxis (migration) and documents results in the laboratory information system. The laboratory issues a report to the ordering pediatric infectious disease or immunology provider who integrates results with clinical findings to guide diagnosis and management.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when a separate professional interpretation of the assay is billed by the physician/laboratory director distinct from the technical performance.
`TC`	Technical component	Use when billing only the laboratory technical processing and instrumentation without professional interpretation.
`90`	Reference (outside) laboratory	Use when the specimen is sent to an outside reference laboratory for testing.
`59`	Distinct procedural service	Use when this assay is a distinct service from other laboratory procedures performed the same day on the same patient.
`52`	Reduced services	Use when the test is partially performed or abbreviated relative to the full procedure.
`53`	Discontinued procedure	Use if testing was started but discontinued for patient- or specimen-related reasons.
`22`	Unusual procedural services	Use when the laboratory documents and bills for significantly greater work or resources than typical for the assay.
`78`	Unplanned return to the operating/procedure room by same physician	Rare for labs; use only if a procedure-related complication required immediate return and lab testing is part of that service.
`80`	Assistant surgeon	Not typically used for this lab test; included for cases where a procedural assistant is billed in a related surgical encounter.
`90`	Reference (outside) laboratory	Duplicate entry avoided; see above.

Taxonomy Code	Specialty	Notes
`207RH0000X`	Pediatric Hematology-Oncology	Specialists ordering and interpreting neutrophil function studies in children.
`207L00000X`	Allergy & Immunology	Common referring specialty for neutrophil functional testing for immune deficiency workups.
`207K00000X`	Clinical Pathology / Laboratory Medicine	Laboratory directors and pathologists overseeing performance and interpretation.
`208000000X`	Pediatrics	Pediatricians who coordinate initial workup and referrals.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`D71`	Functional disorders of polymorphonuclear neutrophils	Directly relevant; indicates inherent or acquired neutrophil functional abnormalities assessed by chemotaxis testing.
`D72.829`	Other specified disorders of white blood cells	Used when a specific neutrophil function disorder is suspected but not otherwise classified.
`D84.1`	Defects in the complement system	Complement defects can present with recurrent infections; chemotaxis testing may be part of broader immune evaluation.
`B95.61`	Methicillin susceptible Staphylococcus aureus as the cause of diseases classified elsewhere	Relevant when recurrent bacterial infections (e.g., S. aureus) prompt evaluation of neutrophil function.
`L08.9`	Local infection of the skin and subcutaneous tissue, unspecified	Common clinical presentation prompting assessment of neutrophil chemotaxis in patients with recurrent skin infections.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`86155`	Leukocyte migration/chemotaxis assay; technical performance	Primary code for the laboratory technical test that measures neutrophil chemotaxis.
`86060`	White blood cell (WBC) count, automated; performed as part of initial evaluation	Often performed before or alongside chemotaxis testing to document leukocyte numbers and differential.
`85025`	Blood count; complete (CBC) automated and automated differential WBC count	Common baseline test in the infectious/immunologic workup prior to functional assays.
`86361`	Immunoassay for infectious agent antibody; qualitative or semiquantitative (e.g., when screening for specific infections)	May be performed in parallel to evaluate for infectious etiologies contributing to neutrophil dysfunction.
`87471`	Infectious agent detection by nucleic acid (example)	Molecular testing for pathogens when infections are recurrent and may prompt related lab panels.