A rare case of granuloma annulare in a 5-year-old child with type 1 diabetes and autoimmune thyroiditis.

Granuloma annulare (GA) has rarely been reported in childhood, and its etiology still remains unclear. Its association with type 1 diabetes (T1D) and other chronic systemic diseases such as autoimmune thyroiditis (AT) or rheumatoid arthritis has been reported. There is no description in the literature of pediatric cases and the simultaneous association of GA and multiple autoimmune diseases in the same subject. We report the case of a 5-year-old girl who presented onset signs and symptoms of T1D. The diagnosis of T1D was confirmed by the presence of autoimmune T1D antibodies. Moreover, AT was also diagnosed by autoantibodies and positive ultrasound. One month later, coin-size erythematous lesions appeared initially on the trunk but soon spread over the body. Once dermatophytosis had been excluded, a skin biopsy confirmed a diagnosis of GA. Although a clear mechanism remains still unknown, clinicians must take into consideration an association of GA in patients with T1D or AT to avoid unnecessary medical investigations and/or inadequate pharmacological treatment.