A comparison between a commercial coagglutination test and conventional throat culture for the detection of group A streptococci in throat swabs.

A co-agglutination test (Phadirect Strep A) for rapid detection of group A streptococci in throat swabs was compared with conventional throat culture in 264 patients with pharyngotonsillitis and fever. The test was easy to perform and proved to have a satisfactory sensitivity and specificity. The predictive value of a positive test will be high also when the prevalence of streptococcal disease is low.