Urinary chloride
Definition
The urine chloride test measures the amount of chloride in the urine.
How the Test is Performed
After you provide a urine sample, it is tested in the lab. If needed, the health care provider may ask you to collect your urine at home over a period of 24 hours. Your provider will tell you how to do this. Follow instructions exactly so that the results are accurate.
How to Prepare for the Test
Your provider will ask you to temporarily stop taking any medicines that may affect the test result. Tell your provider about all the medicines you take, including:
- Acetazolamide
- Corticosteroids
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
- Water pills (diuretic medicines)
DO NOT stop taking any medicine before talking to your provider.
How the Test will Feel
The test involves only normal urination. There is no discomfort.
Why the Test is Performed
Your provider may order this test if you have signs of a condition that affects body fluids or acid-base balance.
Normal Results
The normal range is 110 to 250 mEq per day in a 24-hour collection. This range depends on the amount of salt and fluid you take in.
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test result.
What Abnormal Results Mean
A higher than normal urine chloride level may be due to:
- Low function of the adrenal glands
- Inflammation of the kidney that results in salt loss (salt-losing nephropathy)
- Potassium depletion (from the blood or body)
- Production of an unusually large amount of urine (polyuria)
- Too much salt in the diet
Decreased urine chloride level may be due to:
- Body holding in too much salt (sodium retention)
- Cushing syndrome
- Decreased salt intake
- Fluid loss that occurs with diarrhea, vomiting, sweating, and gastric suction
- Syndrome of inappropriate ADH secretion (SIADH)
Risks
There are no risks with this test.
References
Kamel KS, Halperin ML. Interpretation of electrolyte and acid-base parameters in blood and urine. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 24.
Oh MS, Briefel G, Pincus MR. Evaluation of renal function, water, electrolytes, and acid-base balance. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 15.
Villeneuve P-M, Bagshaw SM. Assessment of urine biochemistry. In: Ronco C, Bellomo R, Kellum JA, Ricci Z, eds. Critical Care Nephrology. 3rd ed. Philadelphia, PA: Elsevier; 2019:chap 55.