15-Year old girl with APS type IIIc, 12 months post-thymectomy remission of myasthenia

  Polyglandular autoimmune syndromes (PAS) is a group of heterogenous conditions characterized by the association of at least two organ-specific autoimmune disorders, concerning both endocrine and non-endocrine organs. Type III is defined as the combination of autoimmune thyroid disease and other autoimmune condition (other than Addison’s disease) and is divided into four subtypes. We describe a teenage female patient – with the family history of autoimmune diseases, who has simultaneously developed the symptoms of autoimmune thyroid disease with the clinical picture of hyperthyroidism and myasthenia gravis at the age of fifteen. Graves’ disease was diagnosed approximately 2 months before myasthenia. Co-occurance of those two diseases allowed us to diagnose PAS type IIIC, however it caused specific diagnostic and treatment difficulties. Furthermore, several months after the diagnosis the patient was found to be GAD-Ab positive, whilst the glycaemic control remained normal. No evidence of other autoimmune conditions was observed. This patient received the standard GD and MG treatment. When the CT scan revealed thymus enlargement, thymectomy was performed. After the surgery we have observed not only remission of MG, but also a significant decrease of TRAb as well, that lasted for a year after the thymectomy. Our patient’s case suggests that in patients diagnosed with PAS, the organ-specific Ab screening can help identify other latent and subclinical autoimmune diseases before clinical symptoms develop. The achievement of post-thymectomy remission of both MG and GD may indicate a close immunological relationship between PAS components.