Endocrine Abstracts

Adrenal insufficiency is a potential life-threatening condition due to lack of cortisol and early diagnosis and management is potentially lifesaving. We describe a 79-year-old lady who presented to the emergency department with new onset confusion, nausea, vomiting and decreased oral intake. Her relatives also reported a one month history of lethargy and weakness. She suffered from gastro-oesophageal reflux for which she was taking Ranitidine, and had a history of total abdominal hysterectomy and bilateral salpingoophorectomy. She was a non-smoker and a non-alcoholic and was previously independent in activities of daily living. On examination, she looked lethargic with a BP of 110/60 mmHg. There was no postural drop. The other parameters including capillary blood glucose were normal. Systemic examination was unremarkable. A complete blood count was normal. However, she had severe hyponatraemia on admission (Na 110 mmol/L). Potassium was normal. She had been admitted few months before with severe hyponatraemia requiring intensive care treatment with hypertonic saline. A CT thorax, abdomen and pelvis had been unremarkable. A morning (9am) cortisol level was taken and deemed suspiciously low (143 nmol/L). A short Synacthen test was performed, confirming hypocortisolaemia:

Additional investigations were consistent with a diagnosis of primary autoimmune adrenal insufficiency, as evidenced by

Serum ACTH - 402++ pg/ml (10-48) ↑

Adrenal cortex antibodies - >1:10+++(<1:10) ↑

Renin – 381++ ng/L (12.6-28.0) ↑

Aldosterone – 6.0 ng/dl (2.2-35 – 30mins in upright position)

ARR – 0.2 (<19)

The patient was started on hydrocortisone replacement therapy and fludrocortisone. She was educated by the endocrine specialist nurses (including instructions regarding ‘sick day rules’) and provided with a steroid card. Her clinical condition improved and her serum sodium normalised.