[Immunologic reactions with group-specific antigens of group A Streptococcus in rheumatic fever].

The levels of Group A streptococcal antigens, characterized by group specificity, incorporated in the immune complexes, were measured by enzyme immunoassay, and antibodies to group-specific polysaccharide were titered in patients with rheumatic fever of the minimal activity, running a protracted course. A statistically significant rise of these parameters was revealed in rheumatic patients as against normal subjects or patients with chronic tonsillitis with tonsillogenic cardiopathy. The diagnostic informativeness of these methods was found higher than that of antistreptolysin-O determination. The authors make a conclusion that signs of streptococcal infection persist in cases with the minimal activity of the rheumatic process and discuss rational antibiotic therapy of such patients. The described methods are recommended for the diagnosis and differential diagnosis of rheumatic fever of low activity.