Clinical Profile of Addison's Disease in a Tertiary Care Institute, Southern India - The Changing Landscape.

Aims and Objectives: Clinical, biochemical, and radiological profiles of Addison's disease and to assess the various etiological spectrum of primary adrenal insufficiency (PAI) in adults. Materials and Methods: A retrospective cohort study was carried out in the Department of Endocrinology, Madurai Medical College, Madurai between January 2014 and January 2021 over a 7-year period. Inclusion Criteria: All the patients with clinical symptoms and or signs of suspected PAI, such as hyperpigmentation, weight loss, persistent nausea or vomiting, fatigue, and hypotension, were recruited. All suspected cases underwent measurement of 8-AM plasma ACTH and cortisol levels. In possible cases and equivocal cortisol levels, patients underwent Co-syntropin/ACTH stimulation test. To know the underlying etiology of PAI, 21-hydroxylase autoantibodies (21OHAb), thyroid function test, Anti TPO, calcium, parathyroid hormone (PTH), LH and FSH, CT of chest and abdomen, and sputum AFB based on the clinical pattern of involvement were performed. Exclusion Criteria: Patients with onset of PAI at infancy and childhood, secondary adrenal insufficiency or exogenous Cushing's syndrome, and central hypocortisolism, including Sheehan's syndrome, were excluded. Results: Thirty-six patients were diagnosed with PAI in this study; 19 (53%) were females and 17 were males (47%). The median age of diagnosis was 35 years. Patients were divided into acute presentation and subacute presentation. Twenty-six patients presented with acute presentation and ten were presented with progressive evolved symptoms. Non-tuberculous etiology was the predominant finding noted in our cohort study (87%, 31 out of 36 patients). The other causes of Addison disease included isolated auto-immune PAI, polyglandular autoimmune syndrome type 1 and II, APLA Syndrome, and adrenal metastasis. Conclusion: Non-tuberculous causes of PAI are the leading etiology in our retrospective study. Autoimmune PAI and Polyglandular autoimmune syndromes are increasingly being recognized as the cause of Addison's disease. PAI individuals require lifelong surveillance for possible development of coexisting autoimmune syndromes and need for glucocorticoid/mineralocorticoid therapy.