Hyponatremia, IL‑6, and SARS‑CoV‑2 (COVID‑19) infection: may all fit together?

Hyponatremia is the most common electrolyte disorder encountered in clinical practice and is associated with an increased risk of overall mortality in in-patients . The most common cause of hyponatremia is the syndrome of inappropriate antidiuresis (SIAD), which accounts for up to 40–50% of cases, but the prevalence may be higher in some pathological conditions, such as subarachnoid haemorrhage, traumatic brain injury, and pneumonia. Besides infec-tious diseases, several inflammatory conditions may be com-plicated by SIAD. In these situations, interleukin-6 (IL-6), released by monocytes and macrophages, plays a pathogenic role in causing electrolyte impairment by inducing the non-osmotic release of vasopressin