Critical Care Medicine-Renal, Electrolyte and Acid Base Disorders>>>>>Sodium
Question 4#

A 58-year-old woman with past medical history of alcohol abuse and bipolar schizophrenia presents to the hospital after a fall complicated by numerous rib fractures seen on chest x-ray. She is currently not taking any medications. On physical examination, her temperature is 37.1°C, blood pressure is 138/88 mm Hg, pulse rate is 99 beats/min, and respiratory rate is 14 breaths/min, oxygen saturation is 95% on room air. Her neurological, cardiovascular, and abdominal examinations are normal. She exhibits tenderness to palpation over the left chest wall with decreased bibasilar breath sounds. Her chemistry panel is as follows: 

• Sodium 122 mEq/L (mmol/L)
• Potassium 2.8 mEq/L (mmol/L)
• BUN 5 mg/dL
• Creatinine 0.7 mg/dL
• Urine osmolality 117 mOsm/kg
• Urine sodium 18 mEq/L (mmol/L)
• Serum osmolality 266 mOsm/kg
• Glucose 105 mg/dL
• Thyroid stimulating hormone 2.20 mIU/L
• Morning cortisol 16 µg/dL
• Total cholesterol 140 mg/dL
• HDL cholesterol 55 mg/dL
• LDL cholesterol 124 mg/dL
• Triglycerides 162 mg/dL

What is the MOST appropriate management of her hyponatremia?

A. Conivaptan
B. Desmopressin
C. Normal saline infusion
D. Fluid restriction
E. Observation with repeat laboratory testing in 4 to 6 hours

Correct Answer is D

Comment:

Correct Answer: D

This patient’s hyponatremia is due to low solute intake associated with increased consumption of beer which is also known as beer potomania. Beer is low in solutes and electrolytes. Excessive consumption with an otherwise nutritionally poor diet leads to impaired water clearance and therefore dilutional hyponatremia. Typical laboratory findings include low urine sodium, low urine osmolality, and low ADH levels. However, it should be noted, that the concomitant use of diuretics can make the diagnosis of beer potomania more difficult as diuretics will cause increased sodium excretion in urine and thus result in higher than expected urine sodium and osmolality concentrations. 

References:

1. Joshi R, Chou S. Beer potomania: a view on the dynamic process of developing hyponatremia. Cureus. 2018;10:3024.
2. Rafei H, Yunus R, Khurana P. Beer potomania: a challenging case of hyponatremia. J Endocrinol Metab. 2016;6:123-126.