Home
HelpMayo Test ID RCHLU Chloride, Random, Urine
Specimen Required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Container/Tube: Plastic, 5-mL tube
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Useful For
An indicator of fluid balance and acid-base homeostasis
Method Name
Potentiometric, Indirect Ion-Selective Electrode (ISE)
Reporting Name
Chloride, Random, USpecimen Type
UrineSpecimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 14 days |
| Frozen | 30 days | |
| Ambient | 7 days |
Reject Due To
| All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. |
Clinical Information
Chloride is the major extracellular anion. Its precise function in the body is not well understood; however, it is involved in maintaining osmotic pressure, proper body hydration, and electric neutrality. In the absence of acid-base disturbances, chloride concentrations in plasma will generally follow those of sodium.
Since urine is the primary mode of elimination of ingested chloride, urinary chloride excretion during steady state conditions will reflect ingested chloride, which predominantly is in the form of sodium chloride. However, under certain clinical conditions, the renal excretion of chloride may not reflect intake. For instance, during states of extracellular volume depletion, urine chloride (and sodium) excretion is reduced.
Reference Values
No established reference values
Random urine chloride may be interpreted in conjunction with serum chloride, using both values to calculate fractional excretion of chloride.
The calculation for fractional excretion (FE) of chloride (Cl) is
FE(Cl) =(Cl [urine] x Creat [serum])/(Cl [serum] x Creat [urine]) x100
Interpretation
Urine sodium and chloride excretion are similar and, under steady state conditions, both the urinary sodium and chloride excretion reflect the intake of sodium chloride. During states of extracellular volume depletion, low values indicate appropriate renal reabsorption of these ions, whereas elevated values indicate inappropriate excretion (renal wasting). Urinary sodium and chloride excretion may be dissociated during metabolic alkalosis with volume depletion where urine sodium excretion may be high (due to renal excretion of sodium bicarbonate) while urine chloride excretion remains appropriately low.
Cautions
High urine values of other halide ions (eg, bromide, fluoride, iodide) may lead to falsely high readings on the chloride ion-selective electrode (ISE).
Clinical Reference
1. Delaney MP, Lamb EJ: Kidney disease. In: Rifai N, Horvath AR, Wittwer CT, eds: Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. 2018:1308-1309
2. Toffaletti J: Electrolytes. In: Dufour DR, Rifai N, eds. Professional Practice in Clinical Chemistry: A Review. AACC Press; 1993
3. Kamel KS, Ethier JH, Richardson RM, et al: Urine electrolytes and osmolality: when and how to use them. Am J Nephrol. 1990;10:89-102
Method Description
The ion-selective electrode (ISE) module performs indirect measurement of electromotive force (EMF). The ISE module measures the EMF difference between an ISE and a reference electrode. The EMF of the ISE is dependent on the ion concentration of the sample. The EMF of the reference electrode is constant. An electronic calculation circuit converts EMF of the sample to the ion concentration of the sample.(Package insert: Chloride. Roche Diagnostics; 02/2018)
Specimen Retention Time
7 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
82436
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| RCHLU | Chloride, Random, U | 2078-4 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| RCHLU | Chloride, Random, U | 2078-4 |
Day(s) Performed
Monday through Sunday