Summary & Overview
CPT 81190: Targeted CSTB Genetic Test, Family-Specific (Technical Component)
CPT code 81190 represents a targeted molecular diagnostic test for variants in the cystatin B gene (CSTB), performed by laboratory personnel to detect family-specific genetic changes. This code captures the technical laboratory component of a pedigree-directed assay and is relevant to genetic evaluation for familial conditions associated with CSTB alterations. Nationally, such targeted tests are important for confirming inherited risk in affected families and guiding clinical genetic counseling and management.
Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication provides an overview of payer coverage patterns, billing considerations, and the clinical context in which CPT code 81190 is used. Readers will find benchmarks on utilization where available, summaries of common billing practices and modifiers, and a clinical description of when a family-directed CSTB test is clinically appropriate.
The content is intended for a national audience of laboratory managers, billing professionals, genetic counselors, and policy analysts seeking concise guidance on coding and the clinical role of targeted CSTB testing. Data not available in the input will be noted where applicable.
Billing Code Overview
CPT code 81190 describes a laboratory molecular test in which a lab analyst performs the technical component to detect the presence of specific genetic changes in the cystatin B gene (CSTB). The assay is targeted to family-specific genetic variants known to occur in the patient’s relatives, indicating a focused, pedigree-directed molecular analysis.
Service Type: Targeted molecular genetic testing — technical component (laboratory analysis)
Typical Site of Service: Clinical laboratory or molecular diagnostics laboratory
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A patient is referred to a molecular diagnostics laboratory after a neurologist documents a family history of progressive myoclonus epilepsy consistent with Unverricht-Lundborg disease. The ordering clinician (neurology or genetics) provides a blood sample and a requisition specifying targeted testing for known familial variants in the cystatin B gene (CSTB). The lab receives the specimen, verifies patient identifiers and the requested family-specific variants, extracts DNA, and performs a targeted molecular assay (e.g., PCR fragment analysis or targeted sequencing) to detect the presence or absence of the reported CSTB variants. The technical analyst documents assay quality metrics, interprets assay signals relative to the targeted familial alleles, and generates a technical report. If the test includes a separate professional interpretation, a board-certified molecular geneticist reviews and issues the interpretive report. Typical sites of service are an outpatient molecular diagnostics laboratory or hospital-based clinical laboratory. The typical patient scenario includes symptomatic patients with myoclonus and seizures or asymptomatic family members undergoing cascade testing for a known CSTB pathogenic variant.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
11 | Service performed by the physician or other qualified health care professional | Use when the professional component is billed by the ordering laboratory physician for interpretation if split billing applies |