Severe Hyponatremia Presenting with Minimal Symptoms

Hyponatremia is a common electrolyte abnormality, however, encountering a patient with serum sodium level below 100 mEq/L and minimal symptoms is unusual. We present the case of an 86-year-old woman who was found to have serum sodium levels of 99 mEq/L. Her only complaint was difficulty in walking. On admission, and throughout her hospital stay, she did not have altered mental status, focal neurological deficits, or adverse outcomes. Her history, blood work, and urine studies pointed towards a diagnosis of thiazide-associated hyponatremia. Thiazide-associated hyponatremia can occur at any time during the course of thiazide administration. The first step that should be taken to manage this condition is discontinuing the medication. The lesson learned from this case is that the degree of hyponatremia does not always correlate with the severity of symptoms.