Comparison of two slide tests for detection of group A streptococcal antibodies.

Screening sera for streptococcal antibodies is a useful clinical procedure when recent streptococcal infection requires verification. Presently there are two test kits available that detect five (or more) of the antibodies that may be present. These two screening tests were compared using antistreptolysin O (ASO) and antideoxyribonuclease B (ADB) titers as the reference for true streptococcal infection. All four procedures were performed on 69 sera collected from a pediatric population. Both screening tests were found to be sensitive, specific, economical, and easy to perform; however, both were more sensitive to elevated ASO titers than to elevated ADB titers. In certain clinical situations, therefore, antibody titrations may be necessary to document completely recent streptococcal infection.