Effect of Valvular Surgery on Antibody to the Group A Streptococcal Carbohydrate

Abstract
Because previous studies revealed that high levels of antibody to the group A streptococcal carbohydrate (A-antibody) persist in the serum of patients with chronic rheumatic valvular disease, the effect of valvular surgery on the level of this antibody was examined in the present study. Streptococcal antibody titers (ASO, anti-DNAse B, and A-antibody) were determined on 73 patients admitted for cardiac surgery: 36 with chronic rheumatic valvular disease and 37 with nonrheumatic cardiac or coronary disease. While the ASO and anti-DNAse B presurgical titers were similar in rheumatic and nonrheumatic individuals, the levels of A-antibody were significantly higher in rheumatic patients. The effect of blood perfusion during cardiac surgery was reflected by reversion of antibody titers towards the mean value for a normal population. A trend toward a rise in all antibodies was seen in all patients two to seven weeks after surgery. However, after an interval of eight weeks or more following surgery, a significant decline in the A-antibody occurred in rheumatic patients who had undergone excision and replacement of the affected valve, but not in those who had experienced a simple commissurotomy. These findings provide additional evidence to support a relationship between valvular disease and A-antibody level in rheumatic patients.