Anaphylaxis to the 23-valent pneumococcal vaccine: a second explored case by means of immediate-reading skin tests with pneumococcal vaccines.

Anaphylaxis to pneumococcal vaccines is rare. In the only one child with anaphylaxis to a first injection of the 23-valent pneumococcal vaccine that has been explored, skin tests and specific IgE determination diagnosed immediate-type hypersensitivity to pneumococcal antigens. We report the case of a child who tolerated three injections of the 7-valent pneumococcal vaccine, but experienced anaphylaxis to a fourth injection of the 23-valent vaccine. Immediate responses in skin tests diagnosed immediate-type hypersensitivity to the two vaccines. Immunizations with the 7-valent pneumococcal vaccine may induce IgE-dependent sensitization to pneumococcal antigens, responsible for anaphylaxis to subsequent injections of pneumococcal vaccines.