Biomedical subjects
Publications and source records attributed to C G Stephens.
Hemophilus influenzae, usually pathogenic in the pediatric population, caused septicemia and peritonitis in the cirrhotic adult described here. Susceptibility to this unusual adult pathogen was perhaps related to liver disease or corticosteroid treatment. This organism has not previously been associated with the syndrome of spontaneous bacterial peritonitis in an adult.
Sixty-two strains of Streptococcus pneumoniae were studied for their abilities to consume selected components of classical and alternative complement pathways in human sera. The classical pathway was blocked by chelating calcium with ethyleneglycol-bios (beta-aminoethyl ether)-N,N-tetraacetic acid and by removing C4. The alternative pathway was blocked by removing factor B. Each strain's activation of the two pathways was compared with its nonimmune reactivity with the Fc region of immunoglobulin G (IgG). Activation of the classical complement pathway appeared to be independent of such Fc reactivity. Highly Fc-reactive strains, however, were shown to activate the alternative pathway more effectively than did less Fc-reactive strains. Since pneumococcal activation of the alternative pathway requires non-immunospecific IgG, these findings suggest that nonimmune binding of IgG on the pneumococcal surface endows it with complement-activating properties.