The author have injected hyaluronidase on palatine tonsil as a provocation test, and studied serologically 4 times each for detection of antibodies in tonsil parenchyma. 38 persons were injected, of which 14 were normal without any upper respiratory infections, 16 were diagnosed as chronic tonsilitis in our hospital, and 8 were C.O.M. or P.N.S.

Results : 1) The mean ASO titer of normal group before-injection : 75.4 in male, 69.6 in female (mean : 72.5±43.7). 2) The mean ASO titer of C.O.M. & P.N.S. before-injection ; 301.0±188.3. 3) The mean ASO titer of chronic tonsillitis before-injection ; 322.7±169.1. (1) One hour after injection, in comparison with normal group, there was increment of ASO titers of chronic tonsillitis group (p<0.05). (2) 2 days after injection, in comparison with two other control group, there was increment of ASO titers of chronic tonsillitis group (p<0.01). (3) 7 days after injection, in comparison with two other control group, there was no significant increment of ASO titers of chronic tonsillitis group. (4) In spite of provocation test, there was no increment of ASO titers in normal and chronic C.O.M. & P.N.S. groups.