Allergic contact dermatitis was diagnosed in patients showing local eczematous lesions on the skin in close contact with nickel-containing objects. Suspected systemic nickel allergy syndrome (SNAS), was defined as a reaction characterized not only by diffused eczematous lesions (systemic contact dermatitis) but also by extracutaneous signs and symptoms, mainly gastrointestinal, after ingestion of nickel-rich foods (i.e. tomato, cocoa, beans, mushrooms, vegetables, wheat flour, etc). In all cases, the diagnosis was confirmed by means of the epicutaneous patch tests which provoked delayed lesions.