Autoimmune polyendocrine (polyglandular) syndrome type 2 is characterised by autoimmune adrenal failure accompanied by autoimmune thyroid disease and/or type 1 diabetes. Other autoimmune conditions may also be present. Its aetiology is incompletely understood. 

Lassoued and colleagues report the case of a young woman who presented acutely with fever, shock and worsening abdominal pain. She reported a 2-month history of weight loss, and of missing her period. Initial biochemistry demonstrated hyponatraemia, hyperkalaemia, acute kidney injury, elevated liver enzymes, and a serum calcium at the upper end of the normal range. She was resuscitated and treated with parenteral hydrocortisone, but also underwent exploratory laparotomy, given her acute abdominal pain, shock and recent amenorrhoea. This did not detect any pathology, but endocrine biochemistry showed a free thyroxine level of 65pmol/l (reference range 10–20pmol/l), suppressed thyrotrophin (TSH), and low baseline cortisol. 

Thyroid storm (Burch–Wartofsky score 70) and adrenal failure were diagnosed, and the patient was treated with methimazole, propranolol and glucocorticoids to good effect. Adrenocorticotrophin was 70pg/ml, indicating primary adrenal failure. TSH receptor antibody titre was normal, but thyroid peroxidase antibody titre was grossly elevated. The patient became hypothyroid in the months after presentation, and was treated with levothyroxine. She required long term hydrocortisone and fludrocortisone replacement.

The authors diagnosed autoimmune polyglandular syndrome type 2 (Schmidt’s syndrome) given the co-occurrence of autoimmune adrenal failure and autoimmune thyroid disease. They propose that thyroid storm precipitated an acute adrenal crisis in their patient. The authors discuss management of thyroid storm in the acute setting, and also highlight how important it is to consider co-existence of autoimmune conditions at presentation, to ensure that correct treatment is initiated promptly and misdiagnosis is avoided.

Read the full article in Endocrinology, Diabetes & Metabolism Case Reports 2023 EDM 21-0152