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Streptococcus Group A Antigen

Item Value
Approval req'd? No
Available Stat? Yes
Test code P116
Test group Streptococcus
Performed by Microbiology
In House Availability Daily, day and evening shifts until 9 PM
Method Lateral flow immunassay
Collection Instructions Swab tonsils or tonsilar crypts and posterior pharynx.

Deliver immediately to laboratory. refrigerate if transport is delayed.
Container type Polyester (Dacron) swabs x2 in paper envelope or in clean,dry plastic tube (Do not use charcoal transport media)
Amount to Collect 2 swabs
Sample type Throat swab
Preferred volume 2 swabs
Min. Volume 2 swabs

If only one swab is received, Group A Streptococcus Culture will be performed instead of the antigen test.
UCSF Rejection Criteria Swab submitted in charcoal media
Processing notes If antigen test is negative set up a group A strep culture
Normal range Negative
Synonyms Beta-hemolytic Strep; beta-strep
Stability Refrigerated 3 days
Turn around times 1 hour after receipt at China Basin Microbiology
Reflex? Negative samples are automatically reflexed to culture at an additional charge.
Additional information Sensitivity is approximately 70% compared with culture. Culture will be performed automatically on antigen negative samples.

Excess blood or mucus on the swab may interfere with the test performance and may yield a false positive result.
CPT coding 87880
LOINC code 18481-2
Last Updated 6/22/2016 12:33:02
Entry Number 874
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