Hyponatremia and hypernatremia. A systematic approach to causes and their correction.

Disorders of sodium and water metabolism can be approached by following a few basic steps: Thorough history taking and physical examination that focuses on volume assessment and laboratory evaluation that includes serum osmolality, urine osmolality, and urine sodium concentration are usually all that are required for diagnosis. Results of these findings are helpful in guiding therapy. Monitoring serum sodium concentration often to ensure adequate treatment and to avoid potential complications is required in management of both hyponatremia and hypernatremia.