title: β-thalassemia and thyroid failure: is there a role for thyroid autoimmunity?
abstract: Autoimmunity is not believed to be involved in tissue damage of Β-Thalassemia (Β-Thal), although nonspecific triggering of autoimmunity by iron overload has been suggested. We recently re-evaluated thyroid function and autoimmunity in 132 Β-Thal patients born and living in Sardinia Island, where a high prevalence of both Β-Thal and autoimmune disease is well documented and in 1002 age and sex-matched euthyroid individuals from the general population. The prevalence of primary hypothyroidism in Β-Thal patients was 28.7% (38/132), without significant difference between males (M) and females (F). Hypothyroidism was associated with smaller and hypoechoic glands, while no difference in the prevalence of anti-thyroid antibodies (ATA) was found between Β-Thal patients with or without thyroid failure. Interestingly, the prevalence of ATA in Β-Thal women (9.2%) was significantly lower than that found in age-matched euthyroid women (20.0%). Our study confirms that thyroid autoimmunity has no role in the pathogenesis of hypothyroidism in b-Thal. Moreover, the lower ATA prevalence in Β-Thal women suggests that iron overload may inhibit rather then trigger thyroid autoimmunity.
authors.affiliation: Department of Medical Sciences, University of Cagliari, Cagliari, Italy. mariotti@medicina.unica.it
authors.forename: Stefano
authors.initials: S
authors.lastname: Mariotti
authors.forename: Francesca
authors.initials: F
authors.lastname: Pigliaru
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Cocco
authors.forename: Alessandra
authors.initials: A
authors.lastname: Spiga
authors.forename: Stefania
authors.initials: S
authors.lastname: Vaquer
authors.forename: Maria Eliana
authors.initials: ME
authors.lastname: Lai
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000453:epidemiology / Q000276:immunology; D019190:Iron Overload / Q000453:epidemiology / Q000276:immunology; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D016036:Seroepidemiologic Studies; D013967:Thyroiditis, Autoimmune / Q000453:epidemiology* / Q000276:immunology*; D017086:beta-Thalassemia / Q000453:epidemiology* / Q000276:immunology*
chemical_list: D001323:Autoantibodies