Thrombocytopenia of Sepsis

Abstract

Platelet-associated IgG (PAIgG), circulating IgG-containing immune complexes (ICs), plasma beta-thromboglobulin (beta-TG), and platelet factor 4 (PF-4) levels were assayed in 33 consecutive patients with culture-proved bacteremia. Thrombocytopenia occurred in 18%, and no correlation was seen between platelet count and PAIgG, beta-TG, or PF-4. In contrast, when patients were assigned to groups on the basis of rising or stable counts vs falling counts, a significant increase in the frequency of elevated PAIgG was seen in those with falling platelet counts. Elevated ICs did not correlate with PAIgG, platelet count, beta-TG, or PF-4. The results of this study of patients with uncomplicated bacteremia, although clearly demonstrating intravascular platelet activation and suggesting a pathologic role for elevated PAIgG, do not support the hypothesis that platelet-bound serum ICs are responsible for either phenomenon.