Endocrine Abstracts

Polyglandular autoimmune syndrome (PAS) is characterised by the coexistence of two or more autoimmune mediated disorders. While the pathophysiology remains poorly understood, environmental triggers and genetic susceptibility are thought to contribute to the dysregulated immune response. PAS has been classified into three main subgroups: Type 1 is seen in the paediatric population while types 2 and 3 are found in adults with autoimmune thyroid disease and insulin-requiring diabetes, are differentiated by the presence or absence of Addison′s disease, and most commonly present in the third decade. There are very few studies looking at the presentation of type 3 PAS in the elderly. Thyroid dysfunction commonly presents in the elderly, but newly diagnosed antibody positive type 1 diabetes is rare in this group. Coeliac disease is prevalent in nearly a quarter of patients with thyroid disease and 10% of those with type 1 diabetes but also rarely presents late in life. We present a rare case of a 76 year old female with features of type 3 PAS. She had a history of hypertension and dyslipidaemia but no personal or family history of autoimmune conditions. The patient was referred to the endocrinology department for further investigation of diabetes and mild hypercalcaemia in the context of weight loss and thirst. Given her age and mildly elevated HbA1c, she had been diagnosed with type 2 diabetes but on further investigation, was found to be GAD and IA-2 antibody positive and started on treatment for type 1 diabetes. Further evaluation also identified TPO antibody positive hypothyroidism and anti -TTG positive coeliac disease. She had normal vitamin B12 levels showing no evidence of pernicious anaemia, no history of vitiligo and normal cortisol, antinuclear antibody and serum angiotensin converting enzyme levels. She is currently under investigation for probable hyperparathyroidism. This is a unique case of type 3 PAS presenting atypically in an elderly patient. Not only is the age of presentation unexpected, but the lack of pernicious anaemia and other autoimmune features typically seen in type 3 PAS make this very distinctive. It highlights the need for further epidemiological research into this presentation, particularly in the elderly, to allow for early detection of a possible autoimmune syndrome. With an ageing population, further understanding is needed on how to manage these complex autoimmune conditions in this vulnerable group.