Test Id : CLU
Chloride, 24 Hour, Urine
    
        Useful For
            
                
                
                    
                    Suggests clinical disorders or settings where the test may be helpful
                
            
    
    Indication of fluid balance and acid-base homeostasis using a 24-hour urine collection
    
        Method Name
            
                
                
                    
                    A short description of the method used to perform the test
                
            
    
    Potentiometric, Indirect Ion-Selective Electrode (ISE)
    
        NY State Available
            
                
                
                    
                    Indicates the status of NY State approval and if the test is orderable for NY State clients.
                
            
    
    
    
        Reporting Name
            
                
                
                    
                    Lists a shorter or abbreviated version of the Published Name for a test
                
            
    
    
    
        Aliases
            
                
                
                    
                    Lists additional common names for a test, as an aid in searching
                
            
    
    Cl (Chloride) Urine
Electrolytes
Lytes
    
        Specimen Type
            
                
                
                    
                    Describes the specimen type validated for testing
                
            
    
        Urine
    
        Necessary Information
    
    24-Hour volume (in milliliters) is required.
    
        ORDER QUESTIONS AND ANSWERS
    
    | Question ID | Description | Answers | 
|---|---|---|
| TM30 | Collection Duration | |
| VL28 | Urine Volume | 
    
        Specimen Required
            
                
                
                    
                    Defines the optimal specimen required to perform the test and the preferred volume to complete testing
                
            
    
    Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Collection Container/Tube: 24-Hour graduated urine container with no metal cap or glued insert
Submission Container/Tube: Plastic, 5 mL tube or a clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 4 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. Refrigerate specimen within 4 hours of completion of 24-hour collection.
Additional Information:
    
        Special Instructions
            
                
                
                    
                    Library of PDFs including pertinent information and forms related to the test
                
            
    
    
            
    
        Forms
    
    If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.
    
        Urine Preservative Collection Options
    
    Note: The addition of preservative or application of temperature controls must occur within 4 hours of completion of the collection. 
| Ambient | OK | 
| Refrigerate | Preferred  | 
| Frozen | OK | 
| 50% Acetic Acid  | OK | 
| Boric   Acid | OK | 
| Diazolidinyl Urea | OK | 
| 6M Hydrochloric Acid | No | 
| 6M Nitric Acid | No | 
| Sodium Carbonate | OK | 
| Thymol | OK | 
| Toluene | No | 
    
        Specimen Minimum Volume
            
                
                
                    
                    Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
                
            
    
    1 mL
    
        Reject Due To
            
                
                
                    
                    Identifies specimen types and conditions that may cause the specimen to be rejected
                
            
    
    
    
        Specimen Stability Information
            
                
                
                    
                    Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
                
            
    
    | Specimen Type | Temperature | Time | Special Container | 
|---|---|---|---|
| Urine | Refrigerated (preferred) | 14 days | |
| Ambient | 7 days | ||
| Frozen | 30 days | 
    
        Useful For
            
                
                
                    
                    Suggests clinical disorders or settings where the test may be helpful
                
            
    
    Indication of fluid balance and acid-base homeostasis using a 24-hour urine collection
    
        Clinical Information
            
                
                
                    
                    Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
                
            
    
    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
            
                
                
                    
                    Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
                
            
    
    > or =18 years: 34-286 mmol/24 hours
Reference values have not been stablished for patients who are less than 18 years of age.
Reference values apply to 24-hour collection.
    
        Interpretation
            
                
                
                    
                    Provides information to assist in interpretation of the test results
                
            
    
    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
            
                
                
                    
                    Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
                
            
    
    High urine values of other halide ions (eg, bromide, fluoride, iodide) may lead to falsely high readings on the chloride ion-selective electrode.
    
        Clinical Reference
            
                
                
                    
                    Recommendations for in-depth reading of a clinical nature
                
            
    
    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. Elsevier; 2018:1308-1309
2. Kamel KS, Ethier JH, Richardson RM, Bear RA, Halperin ML: Urine electrolytes and osmolality: when and how to use them. Am J Nephrol. 1990;10(2):89-102
    
        Method Description
            
                
                
                    
                    Describes how the test is performed and provides a method-specific reference
                
            
    
    An ion-selective electrode (ISE) makes use of the unique properties of certain membrane materials to develop an electrical potential (electromotive force: EMF) for the measurements of ions in solution. The electrode has a selective membrane in contact with both the test solution and an internal filling solution. The internal filling solution contains the test ion at a fixed concentration. Because of the particular nature of the membrane, the test ions will closely associate with the membrane on each side. The membrane EMF is determined by the difference in concentration of the test ion in the test solution and the internal filling solution.(Package insert: ISE indirect Na, K, Cl for Gen.2. Roche Diagnostics; V13.0 04/2016)
    
        PDF Report
            
                
                
                    
                    Indicates whether the report includes an additional document with charts, images or other enriched information
                
            
    
    
    
        Day(s) Performed
            
                
                
                    
                    Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
                
            
    
    Monday through Saturday
    
        Report Available
            
                
                
                    
                    The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
                
            
    
    
    
        Specimen Retention Time
            
                
                
                    
                    Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
                
            
    
    
    
        Performing Laboratory Location
            
                
                
                    
                    Indicates the location of the laboratory that performs the test
                
            
    
    
    
        Fees :
            
                
                
                    
                    Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
                
            
    
    - Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
    
        Test Classification
            
                
                
                    
                    Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
                
            
    
    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
            
                
                
                    
                    Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
                
            
    
    CPT codes are provided by the performing laboratory.
82436
    
        LOINC® Information
            
                
                
                    
                    Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
                
            
    
    | Test Id | Test Order Name | Order LOINC Value | 
|---|---|---|
| CLU | Chloride, 24 HR, U | 43128-8 | 
| Result Id | Test Result Name | Result LOINC Value 
                                        
                                        Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
                                     | 
|---|---|---|
| CL24H | Chloride, 24 HR, U | 2079-2 | 
| TM30 | Collection Duration | 13362-9 | 
| VL28 | Urine Volume | 3167-4 |