The association of autoimmune thyroiditis (AT), Addison’s disease (always present) and cell-mediated diabetes mellitus is defined as type-2 polyglandular autoimmune disease (Schmidt syndrome). More than 90% of patients have adrenal cortex autoantibodies (ACA) at the onset of the disease. The aim of this study is to evaluate the incidence of positive ACA in autoimmune thyroiditis patients with no clinical signs of adrenal failure.
Patients and Methods 34 patients (31 female; 3 male) affected with autoimmune thyroiditis were screened for ACA using an indirect immunofluorescence test on monkey adrenal tissue (Euroimmune Italia Srl). Patients median age was 15.4 years (range 6.2–27.1), and the median period from diagnosis was 4.9 years (range 0.5–12.0). None of the patients had symptoms suggestive of adrenal failure. ACA were repeated after one year in seven patients.
Results All patients were found to be ACA negative. Furthermore, none of the 34 patients developed adrenal insufficiency during a follow-up period of 4.6 years (range 3.5–6.1).
Conclusions Routine screening for ACA in children with autoimmune thyroiditis does not appear to be justified, and it should be reserved for patients with clinical or biochemical suspicion of Addison’s disease. We follow thyroiditis patients with annual biochemical assessment of adrenal function, and ACA is performed only in patients with suspected associated adrenal disease.