What is the most appropriate initial management?

A 75-year-old woman presented with a 4-week history of lethargy. Her medical history was unremarkable and she took no medication.

On examination, her blood pressure was 140/70 mmHg lying. She was euvolaemic.

Investigations:

serum sodium120 mmol/L (137C144)

serum potassium3.8 mmol/L (3.5C4.9)

serum urea3.0 mmol/L (2.5C7.0)

serum creatinine75 µmol/L (60C110)

short tetracosactide (Synacthen®) test (250 micrograms):

baseline serum cortisol450 nmol/L (200C700)

serum cortisol (30 min after tetracosactide)600 nmol/L (>550)

serum thyroid-stimulating hormone2.5 mU/L (0.4C5.0)

serum free T416.9 pmol/L (10.0C22.0)

urinary sodium70 mmol/L

What is the most appropriate initial management?
A . demeclocycline
B . fluid restriction
C . hydrocortisone
D . intravenous sodium chloride 0.9%
E . tolvaptan

View Answer

Answer: B