Ta. Schlager et al., OPTICAL IMMUNOASSAY FOR RAPID DETECTION OF GROUP-A BETA-HEMOLYTIC STREPTOCOCCI - SHOULD CULTURE BE REPLACED, Archives of pediatrics & adolescent medicine, 150(3), 1996, pp. 245-248
Objective: To evaluate an optical immunoassay rapid antigen test to de
tect group A beta-hemolytic streptococci directly from throat swab spe
cimens. Design: Criterion standard with ''blinded'' comparison. Double
-swab pharyngeal samples were obtained; one swab was cultured and the
other was used for the rapid antigen test. Setting: Microbiology labor
atory in a primary care center at a university teaching hospital. Pati
ents: Two hundred sixty-two outpatients with pharyngitis. Main Outcome
Measure: The results of the optical immunoassay rapid antigen test we
re compared with results of standard aerobic culture. Results: Sixty-t
wo (24%) of 262 samples were culture-positive; 48 of these 62 were pos
itive by the optical immunoassay rapid test (sensitivity, 77%). Of the
200 culture-negative samples, seven (4%) were positive by the rapid t
est (specificity, 96%). Conclusion: The optical immunoassay performed
well, but like other rapid tests, is not sensitive enough to replace s
tandard culture for detection of group A beta-hemolytic streptococci.