SKIN REACTIONS OF PATIENTS AND NORMAL INDIVIDUALS TO PROTEIN EXTRACTS OF STREPTOCOCCI 1

Abstract

Intracutaneous tests with purified nucleoprotein fraction of a hemolytic and of a green streptococcus were studied in 670 individuals. The antigens used were purified till their N content was constant. A similar protein from baker''s yeast was used as a control in part of the work. The hemolytic streptococcus nucleoprotein almost uniformly induced stronger reactions than did the green streptococcus antigen. In individuals over 15 yrs. old, age plays no part in determining the presence or absence of sensitiveness to these antigens. In children under 15 yrs. old there is with increase in age a gradually increasing proportion of positive over negative reactors. This proportion is influenced markedly by the presence or absence in children of rheumatic infection, the % of positive reactors among the rheumatic group outnumbering that in the non-rheumatic group by a wide margin. Since positive reactions may be obtained in a great variety of diseases, the test has no specific diagnostic value. The disease which one has at the time of testing appears to bear some relationship to the state of sensitiveness. Whether this is cause and effect or merely an association more apparent than real, the present work does not reveal.