Stejskal, Reynolds, and Bjørklund examined the frequency of metal allergy in 38 patients with connective tissue disorders (1). Of these patients, 16 had rheumatoid arthritis, 13 had Sjögren’s syndrome, and nine had systemic lupus erythematosus. A control group of 43 healthy age and sex-matched subjects were included in the study. Metal allergy was evaluated using the optimized lymphocyte transformation test MELISA. For all subjects, the primary source of metal exposure was dental metal restorations. Most of the tested patients (87%) reacted to at least one metal, and many (63%) reacted to two or more of the tested metals. 43% of the healthy subjects in the study reacted to one metal, and 18% reacted to two or more metals. The increased frequency of metal allergy in the patient group compared with the control group was statistically significant (P < 0.0001). The most frequent allergens in the study were nickel, mercury, gold, and palladium.

Vera Stejskal is Associate Professor of Immunology at University of Stockholm, Sweden. She is founder and president of the MELISA Medica Foundation. Tim Reynolds is Professor of Clinical Biochemistry at the University of Wolverhampton, and a consultant chemical pathologist working at Burton Hospitals NHS Foundation Trust, Burton upon Trent, United Kingdom. Geir Bjørklund is founder and president of the Council for Nutritional and Environmental Medicine (CONEM).

Reference
1. Stejskal V, Reynolds T, Bjørklund G. Increased frequency of delayed type hypersensitivity to metals in patients with connective tissue disease. J Trace Elem Med Biol 2015; 31: 230-236.