Angiolymphoid hyperplasia with eosinophilia associated with tetanus toxoid vaccination.

Three cases of angiolymphoid hyperplasia with eosinophilia are reported at the site of tetanus toxoid vaccination. All presented as nodules on the upper arm, a known adverse effect of the vaccine following superficial inoculation. Histologically the nodules showed numerous small and medium sized vessels, some lined by hyperplastic endothelial cells with perivascular lymphocytic cuffing and an inflammatory infiltrate of plasma cells, eosinophils and scattered mast cells. Lymphoid follicles replete with germinal centres were identified in the dermis and subcutaneous tissue. Immunostaining revealed a polytypic lymphoplasmacytic infiltrate and a curious IgE reticulated pattern within the germinal centres, a feature described in both Kimura's disease and angiolymphoid hyperplasia. The present study suggests that atopic reaction to tetanus toxoid may be an aetiological factor in some cases of angiolymphoid hyperplasia.