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Temporarily unavailable - Streptococcus Group A Antigen

Note: Grp A strep culture will be performed on sample(s) until the test is again available

Item Value
Approval req'd? No
Available Stat? Yes
Test code P116
Test group Streptococcus
Performed by Microbiology
In House Availability Day shift until 1600 hours each day (to 2100 hours only for ED samples)
Method Latex agglutination
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 (Do not use charcoal transport media)
Sample type Throat swab
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 Stable 72 hours at 4C.
Turn around times 1 hour after receipt at China Basin Microbiology
Additional information Sensitivity is approximately 70% compared with culture. Nonspecific reactions can occur if the specimen is contaminated with saliva,food, beverages, oral sprays, throat lozenges, or the patient has received prior antimicrobial therapy. Culture will be performed automatically on antigen negative samples.

Specimens from ED that are received in Moffitt/Long Microbiology before 9 pm will be sent to China Basin Microbiology for same day testing. Specimens received after 9 pm will be tested the following day.

From other locations, test is run 0730-1600 only, and specimens received after 1600 hours will be processed by culture rather than by the less sensitive antigen test
LOINC code 18481-2
Last Updated 5/24/2014 3:08:12 PM
Entry Number 874
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