Test Code INFLU Influenza A/B Rapid Screen, Nasopharyngeal
Additional Codes
St. Luke's Compendium Code (Iatric): L700.5300
Performing Laboratory
St. Luke's Clinic Laboratories
Methodology
Enzyme Immunoassay (EIA)
Specimen Requirements
A freshly collected nasal or nasopharyngeal swab should be processed within 12 hour of collection.
To Collect Nasal Swabs:
- Use the swabs that come with the kit
- Insert the swab into one of the patient’s nostrils
- Rotate the swab three complete turns pressing firmly against the nasal mucosa to help ensure the swab obtains both cells and mucosa.
- Withdraw the swab from the nasal cavity and place it in one of the RV Reagent D tubes and swirl it against the wall three times.
To Collect Nasopharyngeal Swabs:
- Use the swab that comes with the kit.
- Insert the swab into one nostril, reaching the surface of the posterior nasopharynx.
- Rotate the swab over the surface of the posterior nasopharynx.
- Withdraw the swab from the nasal cavity and place in one of the RV Reagent D tubes and swirl it against the wall three times.
Reference Values
Negative
Sensitivity/Specificity Retrospective Study
Specimen | Influenza A | Influenza B | ||
Sensitivity | Specificity | Sensitivity | Specificity | |
Swab | 78% | 90% | Not available | 98% |
The etiology of respiratory infection caused by microorganisms other than influenza A/B virus will not be established with this test. The test is capable of detecting both viable and nonviable influenza A and influenza B virus particles. The test performance depends on antigen load and may not correlate with cell culture performed on the same specimen. Specimens obtained early in the course of the illness will contain the highest virus titers.
A negative test does not exclude infection with influenza A and B. Therefore, the result obtained with this test should be used in conjunction with clinical findings to make an accurate diagnosis.
Additional testing is required to differentiate any specific influenza subtypes or strains in consultation with the state or public health departments.
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
CPT: 87804 x 2
LOINC: 5862-8- Influenza A
LOINC: 5866-9- Influenza B