Endocrine Abstracts

Case history: A 42-year-old female presented to the emergency department with dizziness, vomiting, abdominal pain and thirst. While investigating a 3-month history of lethargy, menstrual irregularity and weight loss, her GP had found a raised TSH, FSH and LH and had prescribed levothyroxine and, 1 week prior to admission, Adcal-D3 supplements. On examination, she was hypotensive and hyperpigmented.

Investigations: Na⁺130 mmol/l (132–144), K⁺4.8 mmol/l (2.5–5.3), urea 18.9 mmol/l (2.5–7.8), creatinine 275 mmol/l (40–90), Hb 87 g/l (115–165), MVC 92 fl (80–97), serum B₁₂ 1062 ng/l (187–883), folate 18.3 μg/l (3.1–20.5), ferritin 183 μg/l (10–204), amended calcium 3.55 mmol/l (2.20–2.60), albumin 27 g/l (35–50), glucose 4.9 mmol/l (<6), random cortisol 38 nmol/l (100–500), ACTH 748 ng/l (0–46), PTH 0.5 pmol/l (1.5–9.3), TSH 10.31 mU/l (0.35–5.00), free T4 15 pmol/l (9–19), prolactin 281 mU/l (109–557), LH 16 IU/L (>20 post menopausal), FSH 9.0 IU/L (>25 post menopausal) and oestradiol 232 pmol/L (<103 post menopausal). Urgent SST: cortisol 23, 24 nmol/l at 0, 30 min. Positive adrenal antibodies confirmed autoimmune adrenal insufficiency.

Treatment and progress: Intravenous fluids and hydrocortisone were given with a rapid clinical and biochemical improvement. Electrolytes and renal function normalized within a week, but she remained anaemic. Her amended calcium reduced to 2.42 mmol/L within 48 h. Abdominal CT confirmed bilateral adrenal atrophy but no evidence of any neoplastic disease.

Further tests revealed: TSH 18.36 mU/l, fT4 8 pmol/l, TPO antibodies 783 IU/mL (<6), LH 21 IU/l, FSH 18 IU/l, oestradiol 762 pmol/l, consistent with polyglandular autoimmune syndrome type 2. Ovarian and coeliac antibodies were undetected.

Conclusions: 1. Severe symptomatic hypercalcaemia is a rare but important presentation of adrenal insufficiency.

2. Treatment of hypothyroidism in undiagnosed adrenal insufficiency can worsen hypercalcaemia and precipitate an Addisonian crisis.

3. Increased intestinal calcuim absorption is recognised in untreated adrenal insufficiency and oral calcium supplementation can precipitate hypercalcaemic Addisonian crisis.

4. Treatment of the Addisonian crisis rapidly corrects hypercalcaemia, renal failure and electrolyte imbalance.

5. Extensive investigations are rarely necessary.