Cerebral salt wasting syndrome, or CSWS for short, is an electrolyte disorder that can occur as a result of cerebral injury. It is characterized by the combination of hyponatremia and hypovolemia (dehydration, volume depletion).
Etiology
CSWS typically occurs in the setting of acute cerebral injury, including after:
Neurosurgical procedure
Stroke
CNS infections (e.g., Meningitis, encephalitis) or Brain tumors
Pathophysiology
The pathophysiology of CSWS is characterized by increased renal sodium excretion (natriuresis), which leads to hyponatremia. The accompanying renal loss of sodium and water causes hypovolemia[^1].
The following mechanisms have been proposed:
Increased release of natriuretic peptides (particularly BNP and ANP), resulting in natriuresis and diuresis
Impaired sympathetic innervation of the kidneys, with decreased sodium reabsorption and reduced renin and aldosterone secretion