Streptomycin-specific antibody coincident with a developing warm autoantibody

The presence of an antibody with specificity against streptomycin-sensitized red blood cells in the serum of a patient with tuberculous pericarditis is reported. Hemolysis and significant anemia were absent. The antibody appeared to develop together with an evolving warm autoantibody, but was clearly separable from the latter. The streptomycin-specific antibody was "penicillin-like" by being totally neutralized in the presence of streptomycin. Red blood cells had to be separately sensitized with streptomycin prior to incubation with the antibody. The antibody cross-reacted with neomycin-sensitized cells and was also neutralized by the presence of neomycin. In addition, a possible cross-reactivity of the streptomycin-specific antibody and the warm autoantibody is suggested. The association of a drug-induced antibody and autoimmune antibody of IgG type is most unusual. In our experience, we have encountered only one similar example.