A new latex agglutination test for rapid diagnosis of group A streptococci.

A rapid diagnostic test for group A streptococci from throat swabs (Culturette Brand 10-Min Strep ID test of Marion Inc.) was performed in 210 patients with acute pharyngitis. This agglutination test is based on the extraction of streptococcal polysaccharide by nitrous acid and observe agglutination with anti-polysaccharide-coated latex suspension. There was a 95.2% total agreement with a standard culture method and agglutination test and specificity of 93.4%, sensitivity of 96.0% positive predictive value of 90.5% and negative predictive value of 97.3%. From the results of our study, the agglutination test for group A streptococci is of diagnostic value. This new kit would be most useful in out-patient clinics, especially in a small private medical office without culture facilities.