Some reports of the study on elevated antistreptolysin O (ASLO) in cases of subacute bacterial endocarditis (SBE). have boon seen, however accounts on clinical pictures and causative organisms have been rarely found.
Nineteen cases, which were admitted to Keio University Hospital with diagnosis of SBE from March 1957 to April 1961, were investigated to clarify relations between ASLO titer and clinical pictures.
Results were as follows:
1) ASLO titer was elevated in 9 cases (47.4 %) among 19 cases, and 8 cases out of those showed elevated ASLO titer more than 500 units.
2) No definite correlation between ASLO titer and age of patients was noted.
3) All cases, of which ASLO titer showed more thrn 500 units, have had any cardiac disease in the past.
4) No direct correlation of the trend of ASLO titer with the efficacy of treatment was found.
5) In 17 out of 19 cases, pathogenic microorganisms were isolated from blood cultures; 11 strains were streptococci viridans, 2 staphylocicci, 3 micrococci and one gram negative bacteria.
6) Experiments to produce streptolysin O in vitro were carried out on 21 strains; however none of those did not produce Streptolrysin O in vitro, though some strains among those were isolated from the cases which showed elevated ASLO titer.
7) Among 9 cases which presented elevated ASLO titer. only 3 cases were considered to develop active rheumatic fever.
8) Causes for the elevated ASLO titer were investigated on 6 cases, however a definite conclusion failed to be obtained.