Clinical Relevance of Contact Allergy to Gold Sodium Thiosulphate in Fibromyalgia

Fibromyalgia is a chronic syndrome characterized by pain, fatigue, and cognitive disturbances. The increased prevalence of contact allergy to gold in individuals with fibromyalgia when compared with the general population has previously been described. Gold contact allergy can manifest as a systemic contact dermatitis, with cutaneous and extracutaneous manifestations presenting upon systemic administration of gold. This study aimed to establish whether gold allergy is of significance in the fibromyalgia population. Prior to patch testing with the Swedish baseline series and an extended dental series, 119 females with fibromyalgia answered questionnaires including details of past medical history, dental history, and previous cutaneous and mucous membrane intolerance to metals. Prevalence of allergy to gold sodium thiosulphate (2.0% and 5.0%) was 33.6% (40 individuals). There was a statistically significant overrepresentation of gold allergy among individuals who experienced cutaneous symptoms upon direct contact with gold (p = 0.010). Contact allergy to gold was more frequent among patients with oral symptoms (p = 0.024). This study demonstrates concordance between reported cutaneous symptomatology related to gold exposure and gold allergy in the fibromyalgia population. Whether individuals with oral symptoms and gold allergy have objective oral clinical findings and relevant gold exposure is the focus of ongoing study.