COMPARISON OF THE GEN-PROBE GROUP-A STREPTOCOCCUS DIRECT TEST WITH CULTURE AND A RAPID STREPTOCOCCAL ANTIGEN-DETECTION ASSAY FOR DIAGNOSIS OF STREPTOCOCCAL PHARYNGITIS

The Gen-Probe Group A Streptococcus Direct Test (GP-ST) is a new assay which utilizes a nucleic acid probe to detect group A streptococci di rectly from pharyngeal swabs. In this study, 1,103 specimens were cult ured and tested by GP-ST. The sensitivities and specificities were as follows: culture, 98.8 and 100%; GP-ST, 92.4 and 99.6%. Of the 1,103 s pecimens, 808 were also tested with the TestPack Strep A assay. For th e specimens tested by all three methods, the sensitivities and specifi cities were as follows: culture, 99.5 and 100%; TestPack Strep A assay , 76.3 and 99.7%; GP-ST, 93.5 and 99.7%. The GP-ST is a very user-frie ndly assay which has the potential to replace culture for the diagnosi s of streptococcal pharyngitis.