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HelpTest Code GASNAT Group A Strep Nucleic Acid Test
Useful For
This test is useful as a qualitative, diagnostictest for the detection of Streptococcus pyogenes (Group A Strep, Strep A) acutepharyngitis infections. Definitive testing results are provided withoutthe need for follow up culture.
Synonyms/Keywords
GASNAT, Strep A, Streptococcal A, Streptococcus pyogenes, Group A Strep
Specimen Requirements
| Specimen Type | Preferred Container/Tube | Acceptable Container/Tube | Specimen Volume | Specimen Minimum Volume (allows for 1 repeat) |
Pediatric Minimum Volume (no repeat) |
|---|---|---|---|---|---|
| Throat Specimen | ESwab-purpletop | 1 Swab | 1 Swab | 1 Swab |
Acceptable Body Sites
Throat
Acceptable Specimen Types
ESwab
Collection/Processing Instructions
- Use the ESwab (purple top-480CFA) Collection and Transport System. Remove the swab from the wrapper.
- Swab the posterior pharynx, tonsil, and other inflamed areas. Avoid touching the tongue, cheeks, and teeth with the swab when collecting specimens.
- Uncap the ESwab transport tube.
- Place the specimen containing swab into the ESwab transport tube and break the swab at the indicated score line.
- Cap the ESwab transport tube.
Note: If patient is presenting at MMC-Marshfield Pediatrics department do not order this test. Order Group A Strep by PCR, Point of Care (GASNATP)
NOTE 2: If patient is presenting at a regional lab site that continues to perform rapid antigen testing and uses PCR from a central laboratory for confirmation of negative samples please collect two swabs by the following process:
- Remove a Puritan polyester swab from the rapid antigen kit and a flocked swab from the ESwab kit. Simultaneously swab the throat with the two swabs. Place the Puritan swab back in the wrapper for RAGT testing. Place the flocked swab into the ESwab tube and break off the shaft at the red score point. If the RADT is negative, refer the ESwab for confirmatory testing by PCR.
Specimen Stability Information
|
Specimen Type
|
ESwab- purple Top | Temperature | Time |
|---|---|---|---|
| 15-30C | 48 hours | ||
| 2-8C | 6 days |
Rejection Criteria
| Sourcesother than throat |
|---|
| Specimensexposed to excessive heat |
| Woodedshafted swabs |
| Calciumalginate swabs |
| Cotton-tippedswabs |
| Frozenswabs |
| Leakingspecimens |
Test Information
Additionally follow-up testing by culture is required if the Xpert Xpress Strep A test results is negative and clinical symptoms persist, or there is an outbreak of acute rheumatic fever.
'ESwab' is a trademark of Copan Diagnostics.
Interferences
To reduce the potential for false negative results, do not collect throat swab specimens immediately after patients have used antiseptic mouthwash
Interpretations
Positive,Negative, or Indeterminate
Reference Range Information
| Performing Location | Reference Range |
|---|---|
| All Performing Sites | No Streptococcal A detected |
Marshfield Labs Performing Department
Marshfield Labs Molecular Pathology
Performing Information
| Performing Location | Day(s) Test Performed | Analytical Time | Methodology/Instrumentation |
| Beaver Dam | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Chetek | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Chippewa Falls | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Colby/Abbotsford | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Cumberland | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Eau Claire | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Greenwood | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Hayward | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Ladysmith | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Lake Hallie | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Marshfield Labs-Microbiology | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Marshfield Clinic-Pediatrics | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Minocqua | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Menomonie | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Merrill | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Mosinee | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Neillsville | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Oakwood | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Phillips | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Park Falls | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Rice Lake | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Stettin | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Stevens Point | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Wausau | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Weston | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
| Wisconsin Rapids | Monday through Sunday | 1 hour | Nucleic Acid Test (PCR Based) |
CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 87651 | QW |
Outreach CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 87651 |
Ordering Applications
| Ordering Application | Description |
|---|---|
| Cerner | Group A Strep Nucleic Acid Test |