A patient with small-cell lung cancer has sodium 120 mmol/L, low serum osmolality, urine osmolality 550 mOsm/kg and urine sodium 60 mmol/L. He is

Question

A patient with small-cell lung cancer has sodium 120 mmol/L, low serum osmolality, urine osmolality 550 mOsm/kg and urine sodium 60 mmol/L. He is clinically euvolaemic with normal thyroid and adrenal function and no severe neurological symptom. What is the initial strategy?

Accepted Answer

Treat the malignancy and begin fluid restriction with close sodium monitoring

Answer

Give fludrocortisone because all euvolaemic hyponatraemia reflects adrenal failure

Answer

Encourage unrestricted water intake to suppress antidiuretic hormone release

Answer

Infuse hypotonic dextrose because concentrated urine proves dehydration

Answer

Give rapid repeated hypertonic saline boluses until sodium is normal in the setting of absence of severe symptoms

Paraneoplastic SIADH — RACP Adult Medicine MCQ

A patient with small-cell lung cancer has sodium 120 mmol/L, low serum osmolality, urine osmolality 550 mOsm/kg and urine sodium 60 mmol/L. He is clinically euvolaemic with normal thyroid and adrenal function and no severe neurological symptom. What is the initial strategy?