Summary & Overview
CPT 86485: Candida Skin Injection Immune Response Test
CPT code 86485 represents a laboratory assay that evaluates a patient’s immunological response to a candida skin injection, used to assess cell-mediated immunity and delayed-type hypersensitivity. The code is nationally relevant for clinicians managing patients with suspected immune dysfunction, pre-transplant evaluations, or monitoring of immunosuppressive therapy where cutaneous antigen challenge informs clinical decision-making.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication outlines coverage patterns and reimbursement considerations among these major payers and summarizes typical sites of service and clinical contexts where the test is ordered.
Readers will learn the clinical purpose of CPT code 86485, typical settings where the test is performed, and what information the code captures for billing and administrative workflows. The report provides benchmarking context, common billing modifiers encountered with this test (listing provided separately), and notes on documentation elements that support coding and claims submission. Data not available in the input is noted where applicable.
Billing Code Overview
CPT code 86485 describes a laboratory test in which a lab analyst evaluates a patient’s immunological response to a candida skin injection. This procedure assesses delayed-type hypersensitivity and cell-mediated immunity by observing the cutaneous reaction to the injected candida antigen.
Service Type: Allergen/skin immunology testing (cutaneous antigen challenge), diagnostic laboratory procedure
Typical Site of Service: Outpatient clinic, dermatology or allergy clinic, or hospital outpatient laboratory setting
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult referred to an outpatient allergy or immunology clinic to evaluate cell-mediated immune function after suspicion of immunodeficiency or to document delayed-type hypersensitivity. The clinician reviews the medical history, including recurrent infections, immunosuppressive medication use (for example, high-dose corticosteroids or chemotherapy), or unexplained poor wound healing. The procedure involves intradermal injection of a standardized candida antigen, measuring induration at 48–72 hours to assess a delayed-type (cell-mediated) immune response. The nursing staff prepares the antigen, administers the intradermal injection (usually on the volar forearm), and documents lot number and site. A follow-up visit or phone contact at 48–72 hours records the transverse induration in millimeters; the clinician interprets the result in context of medications, recent vaccinations, or skin conditions that may affect reactivity. Typical sites of service are outpatient clinics, hospital outpatient departments, and skilled nursing facilities where immune status assessment is needed.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When billing only the physician interpretation portion separate from the technical component |
52 | Reduced services | When the test was partially performed or limited in scope |
53 | Discontinued procedure | When the injection or reading was started but discontinued due to patient intolerance |
54 | Surgical care only | Not typical but used if part of a broader surgical global period (rare) |
55 | Postoperative management only | Rarely applicable; used if only post-procedure management is billed |
62 | Two surgeons | Uncommon; when two physicians of different specialties share responsibility for testing in complex cases |
90 | Reference (outside) laboratory | When the specimen or antigen processing is performed by an outside laboratory |
AS | Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery | Generally not applicable but included when advanced practice clinicians document involvement |
QX | Ordering/servicing physician attests to clinical necessity (modifier for lab) | When the ordering physician also performs or documents the test per payer policy |
QY | Ordering/servicing physician is same group providing service | When the ordering and servicing providers are the same group per payer requirements |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 207RC0000X | Allergy & Immunology | Specialists who frequently order and interpret delayed hypersensitivity testing |
| 208000000X | Family Medicine | Primary care clinicians who may perform testing in outpatient clinics |
| 208000000X | Internal Medicine | Internists evaluating immune status in adults |
| 367A00000X | Clinical Laboratory | Laboratory professionals who handle antigen preparation, storage, and reporting |
| 364S00000X | Nursing | Registered nurses or nurse practitioners who often administer intradermal injections and perform readings |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
D84.9 | Immunodeficiency, unspecified | Used when evaluating suspected cell-mediated immunodeficiency with candida skin testing |
D89.9 | Disorder involving the immune mechanism, unspecified | Broad category for immune dysfunction assessment |
B37.9 | Candidiasis, unspecified | History of fungal infection may prompt immune response assessment, though cutaneous test uses antigen rather than diagnosing active infection |
Z79.899 | Other long term (current) drug therapy | Applied when chronic immunosuppressive therapy (e.g., corticosteroids) may affect test interpretation |
R63.5 | Abnormal weight gain | Included when failure to thrive or weight change raises concern for underlying immunodeficiency |
T45.1X5A | Adverse effect of antineoplastic and immunosuppressive drugs, initial encounter | Relevant when recent cytotoxic or immunosuppressive therapy may suppress delayed hypersensitivity responses |
Z13.89 | Encounter for screening for other diseases and disorders | Used when candida skin testing is performed as part of a screening evaluation for immune function |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
86485 | Candida skin test; delayed type hypersensitivity | Primary code for intradermal candida antigen testing to assess cell-mediated immunity |
95004 | Percutaneous tests with allergenic extracts, immediate type reaction, sequential and incremental, intradermal, percutaneous or patch, single or multiple; reading at 20 minutes | May be performed in the same clinic visit when immediate-type allergy skin testing is also indicated; different immunologic mechanism and timing |
86580 | Skin tests, multiple simultaneous tests, percutaneous, includes test interpretation | Alternative skin testing methods for immediate hypersensitivity; used in allergy evaluation alongside delayed-type testing |
99213 | Office or other outpatient visit for the evaluation and management of an established patient, low to moderate complexity | Typical E/M code used for the clinician visit that orders or interprets the candida skin test |
99000 | Handling and/or conveyance of specimen for transfer from physician's office to a laboratory | Used when specimens or antigen materials require off-site laboratory handling or shipping |
99199 | Unlisted special service, procedure or report | Used only when an unusual ancillary service related to the test does not have a specific CPT code |