There was a statistically significant association between contact allergy to aluminium and persistent subcutaneous nodules in children who had had hyposensitization therapy.

Background: Metallic implants, stents, are increasingly being used especially in patients with stenosis of the cardiac vessels. Ten to thirty per cent of the patients suffer from restenosis regardless of aetiology. We have shown increased frequency of contact allergy to stent metals in stented patients.Objectives: To we evaluate whether contact allergy to stent material is a risk factor for restenosis.Methods: Patients with stainless steel stents, with or without gold plating, were epicutaneously tested and answered a questionnaire. The restenosis rate was evaluated.Results: We found a correlation between contact allergy to gold, gold stent, and restenosis (OR 2.3, CI 1.0-5.1, P ¼ 0.04). The risk for restenosis was threefold increased when the patient was gold allergic and stented with a gold-plated stent. An increased degree of chest pain in gold-allergic patients stented with gold-plated stent was found.Conclusions: We found a correlation between contact allergy to gold, gold-stent, and restenosis. It may be of importance to consider contact allergy when developing new materials for stenting.

As the frequency of contact allergy to gold is higher in stented patients independent of stent type it suggests a previous sensitization. However, several pieces of circumstantial evidence as well as statistical analysis indicate the possibility of sensitization in the coronary vessel by the Au stent. Ni stents and Au stents should not be ruled out as risk factors for induction of contact allergy to these metals.

Gold is released from the Au stent and patients with a Au stent have a fivefold higher B-Au than patients with an Ni stent. The patch test reactions for gold were correlated with B-Au.