Endocrine Abstracts

Background: Autoimmune polyglandular syndrome type 2 is an autoimmune disorder that affects many hormone-producing (endocrine) glands. It is characterized by the presence of Addison’s disease along with autoimmune thyroid disease and/or type 1 diabetes. The initial presentation can be varied but some patient maybe present with subclinical hypothyroidism and later develop Addisonian crisis. The pathogenesis of Autoimmune polyglandular syndrome type 2 remains unclear, although it may occur due to combination of genetic and environmental factors and affects women more than men. Here we present a patient that who was treated for subclinical hypothyroidism which led to adrenal failure.

Case: 46 years Caucasian lady Attended an accident and emergency collapse with a 2-week history of general lethargy and dizziness. She was initially reviewed by her General Practitioner after complaining of tiredness, and weight loss. She had blood tests including a thyroid function test which showed evidence of subclinical hypothyroidism. FT4 16 (pmo/l), TSH 14.70 (Mu/l) She was started on Levothyroxine. 2 months after starting the treatment she became more symptomatic with lethargy and dizzy spells and when she attended Accident and Emergency department she collapses as she was hypotensive BP 80/50. She was given iv fluids, blood test revealed low cortisol of 55. She was started on hydrocortisone initially 100 mg i.m/iv and then 50 mg every 6 hours. Her short synacthen test is below in table 1. A further blood test revealed positive adrenal antibodies. She was discharged home on oral hydrocortisone and fludrocortisone and levothyroxine.

Discussion/conclusion: Subclinical hypothyroidism may be part of polyglandular syndrome Type 2. This consists of hypothyroidism with either adrenal failure or type 1 diabetes. Ruling out adrenal insufficiency is important before starting thyroxine replacement to avoid the life-threatening Addisonian crisis. We recommend carrying out 9 am cortisol followed by a short synacthen test if a 9 am cortisol is low before starting levothyroxine replacement.