Z21 — Asymptomatic human immunodeficiency virus [HIV] infection status
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- Claims must report the appropriate CPT code for the flow cytometry service, include 1 unit of service (UOS), and list the appropriate ICD-10-CM diagnosis code.
- Medical necessity documentation per LCD L34513 is required when coverage criteria are not fully met in this billing guideline (for example, when >24 markers are requested).
- For services requiring a referring/ordering physician, the referring/ordering physician's name and NPI must be reported on the claim.
- Diagnostic test claims should include the test result if known; if result is not available, report the symptoms that prompted the test.
Key Coverage Criteria
- Coverage and medical necessity determinations for flow cytometry are governed by Local Coverage Determination L34513.
- Flow cytometry may be used to analyze cellular components of body fluids and lymphoreticular tissues, including peripheral blood, cerebrospinal fluid (CSF), bone marrow, lymph nodes, tonsil, spleen, and fine needle aspirate material.
- Peripheral blood or fine needle aspirate specimens may be used to avoid more invasive diagnostic procedures when clinically appropriate.
- CPT 88182 reports the physician professional and facility technical components of DNA ploidy and S-phase analysis of tumor by flow cytometry.
- CPT 88184 (first marker) and CPT 88185 (each additional marker) report the facility technical component of flow cytometric immunophenotyping for assessment of potential hematolymphoid neoplasia.
- Flow cytometry interpretation is reported using CPT codes 88187–88189 (one interpretation code per specimen).
20 Active Policies
L39044 — MolDX: Molecular Syndromic Panels for Infectious Disease Pathogen Identification Testing
J05
A58761 — Billing and Coding: MolDX: Molecular Syndromic Panels for Infectious Disease Pathogen Identification Testing
J05
L39995 — Pharmacogenomic Testing
J06
A59915 — Billing and Coding: Pharmacogenomic Testing
J06
Related Codes
Have a follow-up question?
Ask Verity about documentation requirements, denial risks, or coverage in your state.