Summary & Overview
CPT 0107U: Singulex Clarity C. diff Toxins A/B Assay
CPT code 0107U designates a proprietary laboratory assay — the Singulex Clarity® C. diff toxins A/B test — that detects Clostridium difficile toxins A and B in stool using a rapid, multi‑step immunoassay. As a PLA CPT code, 0107U applies to a single, manufacturer‑specific diagnostic test and is used to report performance of this proprietary assay by the producing laboratory. Nationally, PLA codes matter because they identify and track use of unique commercial diagnostic technologies that can influence laboratory workflow, payer coverage decisions, and public health reporting for infectious diseases.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise briefing on the clinical purpose of the test, typical sites of service, and the scope of coverage considerations across major national payers. The publication summarizes benchmarks and policy context relevant to laboratory billing for proprietary assays, outlines common modifier usage where applicable, and provides clinical context for interpreting a positive or negative C. difficile toxin result. The content is intended to inform coding, billing, and payor policy teams, as well as laboratory administrators and clinicians involved in diagnostic strategy and test utilization.
Billing Code Overview
CPT code 0107U is a Proprietary Laboratory Analyses (PLA) code for the Singulex Clarity® C. diff toxins A/B assay by Singulex Labs. The code reports a rapid, highly sensitive, multi–step immunoassay performed on a stool specimen to detect the presence or absence of Clostridium difficile toxins A and B (TcdA and TcdB).
Service type: Laboratory infectious disease diagnostic test
Typical site of service: Clinical laboratory or reference laboratory; specimen collected in outpatient or inpatient settings and sent to the performing laboratory for analysis.
Clinical & Coding Specifications
Clinical Context
A hospitalized adult or outpatient presenting with acute onset of watery diarrhea, abdominal cramping, and recent antibiotic exposure undergoes stool testing to evaluate for Clostridioides difficile infection. A stool specimen is collected in a clean container and sent to the reference or hospital laboratory. The laboratory performs the Singulex Clarity® C. diff toxins A/B assay, a rapid, highly sensitive proprietary immunoassay that detects presence or absence of C. difficile toxins A (TcdA) and B (TcdB) in the stool. Results are reported as positive, negative, or indeterminate and documented in the patient’s chart. Clinical workflow steps include specimen collection, accessioning, test performance on the Singulex platform, result verification by a laboratory technologist, and result reporting to the ordering clinician. Typical sites of service are hospital inpatient laboratories, outpatient hospital labs, and independent specialty reference laboratories. The service type is a single-target laboratory diagnostic test (Proprietary Laboratory Analysis) specific to the manufacturer’s assay.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | (Placeholder - not standard CMS) | Data not available in the input. |
11 |