Culture for Group A Streptococcus

CERNER / EPIC MNEMONIC: C STREPA
POE DESCRIPTION: THROAT CULT/FOR BETA STREP; C STREPA
CPT CODE: 86588
TEST INFORMATION: The test includes a direct antigen screen for Group A Streptococcus. A culture for Group A Streptococcus will be performed for direct antigen screen negative specimens ONLY. Susceptibility testing will NOT be performed.
DAYS PERFORMED: Daily, 24 hours
TURNAROUND TIME: Antigen screen: 2 hours after receipt of the specimen in the laboratory. Because the sensitivity of the antigen screen test is only 60-70%, a culture is set up for all antigen-negative specimens. Preliminary culture reports are available after 24 hours. Complete culture reports are issued 24-72 hours.
SPECIAL INSTRUCTIONS: Specimen should be transported as soon as possible. When transportation is delayed, leave at room temperature.
CONTAINER TYPE: Copan Swab® II
COLLECTION: The tongue should be depressed while both the tonsillar pillars and the oropharynx are swabbed. Exudates should be swabbed and the tongue and uvula avoided.
SPECIMEN REQUIREMENTS: Throat
REJECTION CRITERIA: Inappropriate specimen container, insufficient specimen volume, inappropriate specimen source
MINIMUM VOLUME: One swab
HANDLING INSTRUCTIONS: Specimen should be transported as soon as possible. When transportation is delayed, leave at room temperature.
REFERENCE RANGE: Negative for Group A Streptococcus by direct antigen screening. No Group A Streptococcus isolated.
LIMITATIONS OF TEST: A positive antigen screen result can be relied upon as a rational basis to begin therapy. Therefore, a culture is NOT performed. A negative antigen screen result is only presumptive and due to the low sensitivity of the antigen screening technique, a culture will be performed to reasonably exclude the diagnosis of Group A streptococcal infection. Culture will be screened for Group A Streptococcus ONLY. All Group A streptococci are serologically confirmed.
METHODOLOGY: Direct antigen screen: immunochromatographic assay; Culture: isolation on a medium selective for Group A Streptococcus
ADDITIONAL INFORMATION: Group A Streptococcus, Streptococcus pyogenes, is universally susceptible to penicillin and its derivatives; therefore, susceptibility testing is not performed. The sequelae of poststreptococcal glomerulonephritis and rheumatic fever are diminished by early therapy; therefore, timely diagnosis and early institution of appropriate therapy remains important. Timely therapy may reduce the acute symptoms and overall duration of streptococcal pharyngitis.
TEST SYNONYM(S):Beta-Hemolytic Strep Culture, Throat; Group A Beta Streptococcus Culture, Throat; Rapid Strep Screen; RoutineThroat Culture; Screening Culture for Group A Beta Streptococcus; Strep Throat Screen