Extremely high titers of serum antibodies against the streptococcal exoenzyme deoxyribonuclease B.

In sera from 4 of 25,000 individuals tested for antibodies against streptococci, extremely high antideoxyribonuclease B titers ( > 10(6) U/ml) were found. Two of the cases were diagnosed as monoclonal gammopathies. The M-components were shown to possess the anti-deoxyribonuclease B activity. The other two cases were diagnosed as relapsing erysipelas. The high serum titers of deoxyribonuclease B antibodies were accompanied by a very inflammatory reactivity in the patients' sera and by an oligopolyclonal pattern of immunoglobulin G. In routine diagnoses of streptococcal infections with the anti-deoxyribonuclease B test, patients with extremely high serum titers should be examined for the possible occurrence of gammopathies.