Summary & Overview
CPT 0442U: FebriDx Bacterial/Non-Bacterial Point-of-Care Assay
CPT code 0442U is a PLA code for the FebriDx® Bacterial/Non–Bacterial Point–of–Care Assay from Lumos Diagnostics LLC. The assay uses a fingerstick whole–blood specimen to detect Myxovirus resistance protein A (MxA) and C–reactive protein (CRP) to help distinguish bacterial from non-bacterial respiratory infections. As a PLA code, 0442U represents a single proprietary test tied to a specific manufacturer and is used for tracking, billing, and policy decisions for this unique diagnostic tool.
Key payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The code is relevant nationally for outpatient and point-of-care settings, including urgent care, emergency departments, and primary care clinics where rapid differentiation of bacterial versus non-bacterial respiratory infection can influence diagnostic workflows and antimicrobial stewardship.
Readers will find an overview of the clinical context for the test, the typical sites of service and service type, and the payers covered. The publication summarizes payer coverage considerations, common modifiers associated with billing this PLA code, and practical coding guidance for documentation and claims submission. Data not available in the input are noted where applicable.
Billing Code Overview
CPT code 0442U is a Proprietary Laboratory Analyses (PLA) code that applies only to the FebriDx® Bacterial/Non–Bacterial Point–of–Care Assay from Lumos Diagnostics LLC. The test uses a fingerstick whole–blood specimen to assess a patient with signs and symptoms of a respiratory infection to determine whether the source is bacterial by detecting the presence or absence of the biomarkers Myxovirus resistance protein A (MxA) and C–reactive protein (CRP).
Service Type: Point-of-care infectious disease diagnostic assay using fingerstick whole blood
Typical Site of Service: Point-of-care settings such as urgent care clinics, emergency departments, primary care offices, and other outpatient clinics where fingerstick testing is performed
Clinical & Coding Specifications
Clinical Context
A patient presents to an urgent care clinic with acute onset cough, fever, nasal congestion, and myalgias for 48 hours. The clinician performs a focused respiratory exam and documents concern for an acute respiratory infection where distinguishing bacterial from viral etiology will influence antibiotic prescribing. A fingerstick point‑of‑care test, the FebriDx® Bacterial/Non–Bacterial Point–of–Care Assay (0442U), is performed using a capillary whole‑blood specimen. The assay reports presence or absence of Myxovirus resistance protein A (MxA) and C‑reactive protein (CRP) to support differentiation between likely viral versus bacterial infection. Results are available during the visit and are documented in the medical record; the clinician uses the result to guide immediate treatment decisions, patient counseling, and documentation for the encounter. Typical site of service is an urgent care clinic, primary care office, or other ambulatory point‑of‑care setting. Service type is point‑of‑care diagnostic laboratory testing performed at the bedside or in‑clinic with a fingerstick whole‑blood specimen.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Default — no modifier | Use when no special billing modifier applies. |
26 | Professional component | Use when billing only the physician interpretation/professional component separate from the technical component. |
TC | Technical component | Use when billing only the technical component (test performance/supplies) separate from the professional component. |
QX | Ordering physician not supervising CLIA-waived testing personnel | Use when the test is performed by personnel under a qualified general supervision model and billing requires the modifier. |
QY | Physician directing CLIA-waived testing personnel | Use when the physician or other qualified practitioner directs testing personnel under an approved model. |
QK | Physician performs test personally (specific programmatic contexts) | Use when program rules require indicating the physician personally performed or supervised the test. |
AS | Physician assistant, nurse practitioner, or clinical nurse specialist services | Use when those clinicians provided the service per payer rules and modifier is requested. |
52 | Reduced services | Use when the full test procedure could not be completed or only a partial procedure was performed. |
53 | Discontinued procedure | Use when testing was started but discontinued for patient safety or other valid reason. |
78 | Unplanned return to operating/procedure room | Generally not applicable but may be used if a procedural complication required return for additional testing related to an invasive procedure. |
22 | Increased procedural services | Use when documentation supports substantially greater effort or resources for the testing encounter. |
23 | Unusual anesthesia | Not typically applicable for point‑of‑care testing; included when unusual anesthesia was required during an associated procedure. |
62 | Two surgeons | Not typically applicable; used when two practitioners of the same specialty share responsibility for a procedure. |
QX | Modifier appears above; duplicate entries should be avoided — use once as appropriate. | Use as above. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 207Q00000X | Family Medicine | Common providers performing point‑of‑care respiratory testing in ambulatory settings. |
| 208D00000X | Emergency Medicine | Urgent care / emergency clinicians frequently use rapid diagnostics for acute respiratory infections. |
| 207L00000X | Internal Medicine | Primary care internists performing in‑office point‑of‑care testing. |
| 363L00000X | Nurse Practitioner | NPs often perform and document point‑of‑care tests in ambulatory clinics. |
| 367A00000X | Physician Assistant | PAs commonly conduct testing and manage acute respiratory encounters. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
J06.9 | Acute upper respiratory infection, unspecified | Common presentation where FebriDx may assist in distinguishing viral vs bacterial etiology. |
J02.9 | Acute pharyngitis, unspecified | Pharyngitis evaluation may include point‑of‑care tests to guide antibiotic decisions. |
J20.9 | Acute bronchitis, unspecified | FebriDx can inform likelihood of bacterial involvement in acute bronchitis. |
J18.9 | Pneumonia, unspecified organism | When pneumonia is suspected, FebriDx results may contribute to initial management decisions. |
R05 | Cough | Symptom code frequently present in encounters where rapid differentiation of infection type is desired. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
0442U | FebriDx® Bacterial/Non–Bacterial Point–of–Care Assay — fingerstick whole‑blood test for MxA and CRP | Index PLA code for the point‑of‑care assay used to differentiate bacterial from non‑bacterial respiratory infection. |
36415 | Collection of venous blood by venipuncture | Used if a venous specimen is collected for additional laboratory testing alongside the point‑of‑care fingerstick assay. |
80053 | Comprehensive metabolic panel | Common laboratory panel that may be ordered during the same visit for broader assessment when indicated. |
87804 | Infectious agent antigen detection by immunoassay, respiratory viruses (e.g., influenza) | Performed alongside or prior to FebriDx in some workflows to identify specific viral pathogens. |
87880 | Infectious agent detection by immunoassay, group A streptococcus | Often performed when suspicion for streptococcal pharyngitis coexists with respiratory symptoms. |