Summary & Overview
CPT 86343: Leukocyte Histamine Release Test (LHR)
CPT code 86343 identifies the leukocyte histamine release (LHR) test, an immunology laboratory assay that measures histamine release from a patient’s leukocytes in response to allergens. Nationally, the test is used in specialized allergy evaluation and diagnostic workflows when clinicians need functional evidence of hypersensitivity. Its relevance stems from application in complex allergy cases and in contexts where skin testing or serum IgE testing may be inconclusive.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise review of what the code represents, the clinical context for ordering the test, and the typical laboratory setting of service. The publication outlines payer coverage considerations, common billing modifiers associated with laboratory services, and data availability notes. It also summarizes expected documentation elements and points of policy attention for national payers.
The analysis covers benchmarks for utilization and reimbursement where available, notes on policy updates affecting laboratory allergy testing, and practical coding context to support accurate claim submission. Data not available in the input is noted explicitly in relevant sections.
Billing Code Overview
CPT code 86343 describes a leukocyte histamine release (LHR) test, a laboratory assay performed on a patient’s blood to measure the amount of histamine released during an allergic reaction. The test is used in the clinical evaluation of suspected IgE-mediated hypersensitivity and other allergic responses when assessing a patient’s immunologic reaction to specific antigens.
Service type: Laboratory diagnostic test — immunology/allergy assay
Typical site of service: Clinical laboratory or hospital laboratory
Clinical & Coding Specifications
Clinical Context
A 34-year-old patient with a history of suspected IgE-independent drug allergy presents to an outpatient allergy clinic after recurrent urticaria and hypotensive episodes following a medication exposure. The allergist obtains informed consent and orders a leukocyte histamine release test (86343) to evaluate basophil and leukocyte release of histamine in response to suspected drug and control antigens. Blood is drawn by phlebotomy in the clinic or a contracted laboratory; the specimen is sent to a reference immunology laboratory where the lab analyst performs the 86343 leukocyte histamine release test under controlled conditions. Results are reported to the ordering clinician and used in conjunction with clinical history, skin testing, and other in vitro assays to assess clinical relevance of suspected allergens and guide future management.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When billing only the professional interpretation component and the laboratory bills separately for the technical component |
77 | Repeat procedure by another physician (note: not in provided list) | Data not available in the input. |
52 | Reduced services | When the test is partially performed or truncated and signature documentation supports reduced service |
53 | Discontinued procedure | When testing was initiated but then discontinued for patient safety reasons |
59 | Distinct procedural service (note: not in provided list) | Data not available in the input. |
90 | Reference laboratory | When the service is performed by a reference laboratory separate from the billing provider |
TC | Technical component | When billing only the technical component (laboratory processing) and the ordering clinician bills the professional component |
90 | Duplicate entry removed above | Data not available in the input. |
91 | Repeat clinical diagnostic lab test (note: not in provided list) | Data not available in the input. |
99 | Unlisted or other (note: not in provided list) | Data not available in the input. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
207Q00000X | Allergy & Immunology | Specialists who order and interpret 86343 testing |
208D00000X | Clinical Laboratory | Laboratory directors and pathologists overseeing specialized immunologic assays |
363A00000X | Phlebotomist | Personnel who obtain specimens for testing |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
T88.7XXA | Unspecified adverse effect of drug or medicament, initial encounter | Frequently used when evaluating suspected drug-induced allergic reactions with leukocyte histamine release testing |
L50.9 | Urticaria, unspecified | Indication for testing when chronic or recurrent hives raise concern for an immunologic trigger |
T78.40XA | Allergy, unspecified, initial encounter | General allergy evaluation may include 86343 as part of the diagnostic workup |
T78.2XXA | Anaphylactic shock, unspecified, initial encounter | Post-anaphylaxis evaluation may include laboratory assays to investigate causative agents |
R21 | Rash and other nonspecific skin eruption | Skin manifestations prompting allergy laboratory testing |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
86003 | Antibody; qualitative or semiquantitative, each procedure (e.g., RAST) | Alternative or complementary in vitro allergy testing to assess specific IgE when evaluating allergic sensitization alongside 86343 |
86038 | Allergen specific IgE; quantitative (e.g., ImmunoCAP), each allergen | Commonly ordered to quantify allergen-specific IgE levels when correlating with histamine release results |
99000 | Handling and/or conveyance of specimen (note: not a standard CPT for labs) | Data not available in the input. |
36415 | Collection of venous blood by venipuncture | Preceding procedure required to obtain specimen for 86343 |
94799 | Unlisted pulmonary service or procedure (note: not related) | Data not available in the input. |