Additional Autoimmune Disease Found in 33% of Patients at Type 1 Diabetes Onset

OBJECTIVE: We sought to define the prevalence of nonislet, organ-specific autoantibodies at diagnosis of type 1 diabetes and to determine the prevalence of comorbid autoimmune diseases. RESEARCH DESIGN AND METHODS: Children (n = 491) diagnosed with type 1 diabetes at the Barbara Davis Center for Childhood Diabetes were screened for autoimmune thyroid disease (thyroid peroxidase autoantibodies [TPOAb]), celiac disease (tissue transglutaminase autoantibodies [TTGAb]), and Addison disease (21-hydroxylase autoantibodies [21OHAb]). RESULTS: Of the 491 children, 161 had at least one nonislet autoantibody, and of these, 122 (24.8%) were positive for TPOAb, and 15 of the 122 (12.3%) had autoimmune thyroid disease. There were 57 (11.6%) who were positive for TTGAb, of whom 14 (24.6%) had celiac disease. Five (1.0%) were positive for 21OHAb, of whom one had Addison disease. CONCLUSIONS: Many autoantibody-positive subjects present with additional autoimmune disorders. Detection of these autoantibodies at type 1 diabetes onset may prevent complications associated with delayed diagnosis of these disorders.