Coding Specifications
| Modifier | Description | When to Use |
|---|
00 | Default/No modifier | Use when no specific modifier applies for reporting purposes. |
| 22 | Increased procedural services | Use when the laboratory documents substantially greater work or complexity for this particular analysis beyond typical test complexity (rarely used for PLA tests but applicable if significantly more analyst time is required and documented).
| 26 | Professional component | Use when reporting only the professional component (interpretation) separate from the technical laboratory processing if payor requires split billing and the lab separates TC/26.
| 52 | Reduced services | Use when the service was partially reduced or not completed as normally described (e.g., incomplete analysis due to insufficient sample quality and a reduced interpretive scope).
| 53 | Discontinued procedure | Use if testing was started but discontinued for documented clinical or technical reasons prior to completion.
| 62 | Two surgeons/paired providers (not typical for lab) | Generally not applicable to laboratory testing but retained only if dual-provider professional component arrangements exist; use with caution and documentation.
| 78 | Unplanned return to the operating/procedure room (not typical for lab) | Not generally applicable to PLA codes; only used if relevant in broader surgical contexts.
| 80 | Assistant at surgery (not typical for lab) | Not applicable to laboratory testing; included from source list but infrequently used for this procedure.
| 82 | Assistant surgeon when qualified resident not available (not typical for lab) | Not applicable to laboratory testing.
| 26 | See above | Duplicate entry avoided; professional component remains relevant.
| TC | Technical component | Use when billing only the technical component (sequencing, sample prep, data generation) separate from interpretation if the laboratory splits components and payor requires separate reporting.
| QK | Laboratory performing test (CLIA-defined independent lab) — Modifier pair QK,QX,QY often used for advanced diagnostic services | Use when the test is performed under specific contractual or specimen handling arrangements requiring these QA modifiers as defined by payors; document contractual roles.
| QX | Performing laboratory certification (for lab/physician arrangements) | Use as needed where payor policy requires identification of the performing laboratory versus ordering entity.
| QY | Laboratory performing only portion of test | Use when multiple laboratories share testing steps and payor requires identification of the performing lab’s portion.
| SH | Informatics-only service | Use when a separate informatics or bioinformatics-only professional service is provided and billed separately by a qualified entity.
| Taxonomy Code | Specialty | Notes |
|---|
0000A | Clinical Geneticist | Clinical geneticists order and interpret complex genomic testing and coordinate family-based analyses. |
| 0000B | Molecular Genetic Pathologist | Laboratory specialists who oversee sequencing assays, quality, and interpretation workflows for exome and mitochondrial testing.
| 0000C | Medical Geneticist/Genetic Counselor | Genetic counselors and physicians who provide pre-test counseling, consent, and post-test result communication.
| 0000D | Pediatric Neurologist | Common ordering specialty when developmental delay or neuromuscular disease is suspected.
| 0000E | Clinical Laboratory Scientist/Director | Laboratory directors responsible for test validation, CLIA compliance, and reporting governance.
(Note: taxonomy codes above are illustrative placeholders for common specialties that order or perform this PLA test.)
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|
Q97.0 | Chromosomal mosaicism, not elsewhere classified | Family-based exome analysis can help clarify mosaic inheritance patterns when chromosomal mosaicism is suspected. |
| Q87.8 | Other specified congenital malformation syndromes affecting multiple systems | Exome plus mitochondrial analysis helps evaluate multisystem congenital presentations.
| G40.9 | Epilepsy, unspecified | Genetic epilepsies are commonly investigated with exome sequencing and comparator analyses to identify causative variants.
| E70.0 | Classical phenylketonuria | Metabolic and mitochondrial disorders may overlap clinically; mitochondrial sequencing can be informative alongside biochemical testing.
| R62.0 | Delayed milestone in childhood | Developmental delay is a frequent indication for exome sequencing and family comparator analysis.
| M31.6 | Other necrotizing vasculopathies (example inflammatory multisystem presentation) | Rare presentations with suspected genetic predisposition may prompt exome/mitochondrial testing.
| H35.50 | Unspecified retinopathy, unspecified eye | Hereditary retinal disorders are often assessed with sequencing including mitochondrial analysis when applicable.
| I35.0 | Nonrheumatic aortic (valve) stenosis | Cardiac congenital or familial structural disease may be evaluated with exome sequencing in select cases.
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|
81416 | Exome sequencing, clinical, interpretation and report (eg, proband-only) | May be performed for the proband when exome sequencing is ordered; 0215U is a PLA comparator analysis that specifically uses a relative’s exome to refine interpretation and may be billed in addition to or instead of other exome reporting codes per payor policy. |
| 81479 | Unlisted molecular pathology procedure | Used when a specific molecular test does not have an established CPT code; historically used prior to PLA codes or for ancillary analyses related to comparator workflows if needed.
| 0022U | Targeted genomic sequence analysis (example PLA code) | Other PLA codes for specialized genomic analyses that may be ordered alongside or for comparison; demonstrates that PLA coding is used for unique manufacturer-specific tests.
| 89240 | Cytogenetic analysis, chromosome analysis; blood, 20 cells | In workflows where chromosomal microarray or cytogenetics preceded exome testing, results may complement exome/mitochondrial analysis.
| 82000 | Drug or metabolite assay (example laboratory test) | Laboratory supportive testing such as metabolic studies may be performed in parallel during evaluation of suspected genetic/metabolic disorders.
(Note: Selected CPT codes above represent commonly associated tests in the diagnostic workflow for genetic disorders; billing relationships depend on laboratory and payor policies.)