Test Catalog

Test Id : SGUR

Specific Gravity, Random, Urine

Useful For
Suggests clinical disorders or settings where the test may be helpful

As a partial assessment of the kidney's ability to concentrate urine

Method Name
A short description of the method used to perform the test

Refractometer

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Specific Gravity, U

Aliases
Lists additional common names for a test, as an aid in searching

Urine Specific Gravity

Specimen Type
Describes the specimen type validated for testing

Urine

Ordering Guidance

Urine with contrast dye, glucose, or excessive protein should not be evaluated with this test. In these cases, urine osmolality is a better measure of urine concentration. Order UOSMU / Osmolality, Random, Urine.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube: Plastic urine container

Specimen Volume: 20 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative.

Forms

If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

1 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

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) 7 days
Frozen 7 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

As a partial assessment of the kidney's ability to concentrate urine

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Specific gravity (SG), the ratio of the mass of a solution compared to the mass of an equal volume of water, is an estimate of the concentration of substances dissolved in the solution.

 

Urine SG can be used to assess the kidney's ability to concentrate or dilute urine. However, because protein, glucose, and contrast dye have molecular masses that are relatively large compared to other major components of urine (eg, sodium, chloride, potassium), they disproportionately affect SG. In these cases, urine osmolality is a better measure of urine concentration

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.

1.002-1.030

Interpretation
Provides information to assist in interpretation of the test results

Low specific gravity (SG) (1.001-1.003) may indicate the presence of diabetes insipidus, a disease caused by impaired functioning of antidiuretic hormone (ADH). Low SG also can occur in patients with glomerulonephritis, pyelonephritis, and other renal abnormalities. In these cases, the kidney has lost its ability to concentrate due to tubular damage.

 

High SG may occur in patients with adrenal insufficiency, hepatic disease, congestive heart failure, or in patients experiencing excessive water loss due to sweating, fever, vomiting, or diarrhea.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Schumann GB, Schweitzer SC: Examination of urine. In: Kaplan LA, Pesce AJ, eds. Clinical Chemistry, Theory, Analysis and Correlation. 3rd ed. Mosby-Year Book Inc; 1996:1118-1119

2. Free HM, ed: Modern Urine Chemistry (Manual). 8th ed. Bayer Corp; 1996:36-37

3. Perrier ET, Bottin JH, Vecchio M, Lemetais G: Criterion values for urine-specific gravity and urine color representing adequate water intake in healthy adults. Eur J Clin Nutr. 2017 Feb;71:561-563

Method Description
Describes how the test is performed and provides a method-specific reference

The refractive index of a material, which is its light-bending power as compared to air, is a physical constant, which varies directly with the chemical composition of a substance. This is accomplished by viewing a drop of solution through a lens-prism system of the total solids meter (refractometer). The refractometer measures total solids in urine to an accuracy of 0.1 g/100 mL and since it requires about 0.25 g/100 mL in total solids to change the specific gravity by about 0.001 units, optical urinometry proves excellent for clinical measurement of specific gravity. Refractometers are temperature compensated and will read standards correctly only at temperatures between 20 degrees C and 30 degrees C.(Minton DM, O’Neal EK, Torres-McGehee TM: Agreement of urine specific gravity measurements between manual and digital refractometers. J Athl Train. 2015;50[1]:59-64)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

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 Sunday

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.

Same day/1 day

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

2 Days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

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 Regional Manager. 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.

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports