SEROLOGIC RESPONSE TO STREPTOCOCCAL HEMOLYSIN AND HYALURONIDASE IN STREPTOCOCCAL AND RHEUMATIC INFECTION

Abstract

Antistreptolysin and streptococcal antihyaluronidase titers were detd. in the sera of patients with acute rheumatic fever and streptococcal infection collected in the winter and spring of 1948-1949. The geometric mean titers of the sera from patients with rheumatic fever were higher than those found after scarlet fever in both the antihyaluronidase and antistreptolysin tests. This difference varied somewhat from yr. to yr. in each test. Study of pairs of sera obtained from patients at the onset of symptoms of scarlet fever and 3 weeks later showed a wide range of variation in the degree of serologic response to each antigen. There was no correlation between the increase of antistreptolysin and of antihyaluronidase titers in individual patients convalescent from scarlet fever. On comparing the sets of data obtained by each test it was found that a greater number of patients showed no increase in the titer of antihyaluronidase than of antistreptolysin. This was also reflected in the fact that many convalescents from scarlet fever had very low antihyaluronidase titers, whereas all of these titers in active rheumatic fever were well within the measurable range. This difference was much less marked in the case of antistreptolysin. Annual variation in the mean antihyaluronidase titers in acute streptococcal infection and active rheumatic fever, and especially in the breadth of distribution of this titer in the 2 diseases, is shown to be a possible source of increased limitation in the diagnostic application of this test.