Abstract

Highly purified capsular polysaccharides from groups A, B, and C meningococci and from two strains of Escherichia coli did not aggregate human or dog platelets in vitro. Nor was there any detectable effect on platelet aggregation induced by adenosine diphosphate (ADP), epinephrine, or collagen. The results do not support the hypothesis that capsular polysaccharides are involved in the pathogenesis of thrombocytopenia often seen in severe infections with these bacteria.