Description
Urinary sodium measurement is useful in the work-up of acute renal failure and in the differential diagnosis of hyponatremia. The renal threshold for sodium is between 110 and 130 mmol/24Hrs Urine.
Excretion of urinary sodium is highly dependent on dietary intake and state of hydration.
Indications
High levels of urinary sodium are found in increased sodium intake, primary and secondary adrenal failure, renal tubular acidosis, syndrome of inappropriate antidiuretic hormone (SIADH) and Bartter’s syndrome. Low levels of sodium in urine are associated with low sodium intake, premenstrual sodium and water retention, adrenocorticoid hyperfunction, congestive heart failure, diarrhea and excessive sweating.
Sample Type, Quantity & Conditions
5 ml of 24 Hrs Urine 5 ml Urine Stability: 7 Days at 15-25 °C 14 Days at 2-8 °C 14 Days at (-15)-(-25) °C
Special Precautions
State 24 Hrs urine volume. Do not use pH adjusted urine samples.
Normal Range
40 - 220 mEq/24 Hrs 40 - 220 mmol/24 Hrs
