Metal allergy is common in patients with various diseases affecting the skin (psoriasis, eczema), autoimmune diseases (multiple sclerosis, SLE, thyroiditis, Sjögren’s syndrome) and gastrointestinal diseases. Patients with symptoms of profound fatigue of unclear etiology (fibromyalgia, CFS) may be suffering from allergy induced by metals.
Candida allergy, drug allergy (such as to penicillin) and allergy to chemicals (such as formaldehyde) can also be tested. MELISA has been developed to test for Borrelia to improve the diagnosis of Lyme disease. Avoidance of allergens often results in significant health improvement for the patient. Follow-up MELISA testing usually shows reduced lymphocyte reactivity as well.
In addition to dental fillings such as amalgam and gold, and dental implants containing titanium, metals are found in orthopaedic and surgical implants such as hip joints, knee prostheses and pacemakers. In the majority of patients, these implants are tolerated. However, in rare instances, the implants may induce side-effects in hypersensitive patients such as pain, dermatitis, cutaneous swelling, impaired wound healing, bone infections and implant loosening. Although bacterial infection is often the cause of implant rejection, sometimes no bacteria are detected despite inflammation. These adverse effects may be compounded by metal debris created by the wearing of metal on metal implants. Nickel, cobalt and chromium are known metal allergens.
Recently, cases of titanium allergy have also been described in scientific literature. Titanium is a transition metal and thus may function as a hapten and trigger cellular hypersensitivity. Since titanium is used as white pigment in toothpastes, cosmetics and medicines, the latent sensitization of susceptible individuals is possible. Case reports describe the disappearance of symptoms after the removal of the implant and positive delayed-type reactions are confirmed by patch testing or by decreased lymphocyte proliferation to specific metal allergens in vitro. MELISA screening prior to implantation can detect the possible existence of sensitization and allow the most compatible materials to be used for each individual patient.