Subcutaneous nodules following treatment with aluminium-containing allergen extracts.

We describe two patients who developed multiple itching nodules following immunization with vaccines adsorbed on aluminium hydroxide. Both patients had been treated with vaccines for extrinsic asthma and rhinitis for 4 and 10 years respectively. The lesions were persistent and lasted for several years. Histopathological findings were those of a foreign body reaction. Aluminium was most probably involved in the pathogenesis of these lesions because its presence could be demonstrated in macrophages using energy-dispersive X-ray microanalysis. Although some symptomatic relief was achieved with topical corticosteroids and oral antihistamines, treatment was unsuccessful.