Hyponatremia: a case report of SIAD

Hyponatremia, defined as serum sodium concentration <136 mEq/l, represents one of the most frequently encountered electrolyte disorder in clinical practice. Among hospitalised patients up to 15-30% present mild hyponatremia (130-135 mEq/l), whereas moderate to severe forms are seen in up to 7% of inpatients. Hyponatremia is associated with significant morbidity and mortality especially in patients with underlying diseases. According to volume status hyponatremia can be classified as hypovolemic, hypervolemic or euvolemic. An accurate diagnostic algorithm has to be performed in order to optimize the therapeutic approach. Acute and severe forms are accompanied by neurological symptoms due to cerebral edema and can cause death if not appropriately treated. Moreover, even a too rapid correction can be associated with serious complications, such as the osmotic demyelination syndrome. Hypovolemic forms have to be treated with isotonic saline infusion, whereas eu-hypervolemic forms require hypertonic saline when symptomatic, and fluid restriction or vaptans when asymptomatic. Here, we report the case of a 79-year-old woman with hyponatremia admitted to the Emergency Department of XXX.