Differences in clinical and biochemical parameters between CSW versus SIADH
| CSW | SIADH | |
| Body weight | same or ↓ | ↑ |
| Extracellular volume | ↓ | ↑ |
| Signs or symptoms of dehydration | present | absent |
| Central venous pressure | ↓ | same or ↑ |
| Plasma sodium | ↓ | ↓ |
| Urine sodium | ↑ | ↑ |
| Net sodium loss | ↑ | normal |
| Urine output | normal or ↑ | ↓ |
| Serum osmolality | ↓ | ↓ |
| Urine osmolality | ↑ | ↑ |
| Blood urea nitrogen | normal or ↑ | ↓ |
| Plasma AVP | ↓ | ↑ |
| Haematocrit | normal or ↑ | ↓ |
| Plasma aldosterone | ↓ | normal or ↑ |
| Plasma renin | normal, ↑ or ↓ | ↓ |
| Treatment | Salt supplementation and fluid replacement | Fluid restriction |
*increased; ↓, decreased.
AVP, antidiuretic hormone vasopressin; CSW, cerebral salt wasting syndrome; SIADH, syndrome of inappropriate antidiuretic hormone.