Supersaturation Profile, 24 Hour Urine




Test Mnemonic

SSAT24

CPT Codes

  • 84540 - QTY (1)
  • 84560 - QTY (1)
  • 84392 - QTY (1)
  • 84300 - QTY (1)
  • 84133 - QTY (1)
  • 83935 - QTY (1)
  • 83945 - QTY (1)
  • 83986 - QTY (1)
  • 84105 - QTY (1)
  • 83735 - QTY (1)
  • 82570 - QTY (1)
  • 82140 - QTY (1)
  • 82340 - QTY (1)
  • 82436 - QTY (1)
  • 82507 - QTY (1)

Includes

  • Calcium Oxalate crystal
  • Brushite crystal
  • Hydroxyapatite crystal
  • Uric Acid crystal
  • Potassium
  • Sodium
  • Calcium
  • Magnesium
  • Chloride
  • Phosphorus
  • Sulfate
  • Citrate Excretion
  • Oxalate
  • pH
  • Uric Acid
  • Creatinine
  • Osmolality
  • Ammonium
  • Urea Nitrogen
  • Protein Catabolic Rate

Performing Laboratory

Mayo Clinic Dpt of Lab Med & Pathology


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
35 mLUrine, 24-hour (well-mixed)Clean container (No preservatives)Refrigerate during collection.RefrigeratedRefrigerate specimen during and after collection. Specimen pH should be between 4.5-8.0 and will stay in this range if kept refrigerated. Specimens with pH >8 indicate bacterial contamination, and testing will be cancelled. Do not attempt to adjust pH as it will adversely affect results. 24-hour volume is required. Patients height in centimeters and weight in kilograms are required if patient is less than 18 years old.

Minimum Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
25 mL     

Stability

Environmental Condition Description
Ambient3 days
Frozen14 days
Refrigerated14 days

Days Performed

Sun - Sat

Turnaround Time

3 - 6 days

Methodology

Name Description
Colorimetric Enzyme Assay 
Enzymatic 
Freezing Point Depression 
Photometric 
Uricase 
Colorimetric Endpoint 
Calculation 
High-Performance Ion Chromatography (HPIC) 
Kinetic UV Assay 
pH Meter 
Potentiometric, Indirect Ion-Selective Electrode (ISE) 

Reference Range

Ammonium, 24Hr, Ur
Sex Age From Age To Type Range Range Unit
 18 Years77 YearsNormal15 - 56mmol/24 hr
   Years17 YearsNormalNot established 
 78 Years99 YearsNormalNot established 
Brushite Crystal
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormalReference Mean = 0.21DG
Calcium Oxalate Crystal
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormalReference Mean = 1.77DG
Calcium,Urine
Sex Age From Age To Type Range Range Unit
Male18 Years99 YearsNormal< 250mg/24 hrs
Female18 Years99 YearsNormal< 200mg/24 hrs
   Years17 YearsNormalNot established 
Chloride,Urine
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal34 - 286mmol/24 hr
   Years17 YearsNormalNot established 
Creatinine,Urine
Sex Age From Age To Type Range Range Unit
Male18 Years99 YearsNormal930 - 2,955mg/24 hrs
Female18 Years99 YearsNormal603 - 1,783mg/24 hrs
   Years17 YearsNormalNot established 
Hydroxyapatite Crystal
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormalReference Mean = 3.96DG
Magnesium,Urine
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal51 - 269mg/24 hrs
   Years17 YearsNormalNot established.
Osmolaltiy, 24Hr, Ur
Sex Age From Age To Type Range Range Unit
   Months11 MonthsNormal50 - 750mOsm/kg
 1 Years99 YearsNormal150 - 1,150mOsm/kg
Oxalate,U mg/spec
Sex Age From Age To Type Range Range Unit
 16 Years99 YearsNormal9.7 - 40.5mg/24 hrs
    15  NormalNot established 
Oxalate,U mmol/spec
Sex Age From Age To Type Range Range Unit
 16 Years99 YearsNormal0.11 - 0.46mmol/24 hr
   Years15 YearsNormalNot established 
pH,Urine
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormal4.5 - 8.0.
Phosphorus,Urine
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal266 - 1,797mg/24 hrs
   Years17 YearsNormalNot established 
Potassium,Urine
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal16-105mmol/24 hr
   Years17 YearsNormalNot established 
Protein Catabolic Rate, Ur
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormal56 - 125g/24 hour
Sodium,Urine
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal22-328mmol/24 hr
   Years17 YearsNormalNot established 
Sulfate,Urine
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormal7 - 47mmol/24 hr
Urea Nitrogen
Sex Age From Age To Type Range Range Unit
 18 Years99 YearsNormal7 - 42g/24 hrs
   Years17 YearsNormalNot established 
Uric Acid Crystal
Sex Age From Age To Type Range Range Unit
   Years99 YearsNormalReference Mean = 1.04DG
Uric Acid,Urine
Sex Age From Age To Type Range Range Unit
Male18 Years99 YearsNormal200 - 1,000mg/24 hrs
Female18 Years99 YearsNormal250 - 750 mg/24 hrs
   Years17 YearsNormalNot established 

Special Info

Refrigerate specimen during and after collection. Specimens with pH > 8.0 will be rejected. Do not attempt to adjust pH as it will adversely affect results. This test is New York DOH approved.

Clinical Info

This test is useful in diagnosis and management of patients with renal lithiasis by predicting the likely composition of the stone in patients who have a radiopaque stone or for whom stone analysis is not available. Results may help in designing a treatment program, identify specific risk factors for stones, monitor the effectiveness of therapy, evaluate kidney excretion of acid and urine pH and estimate a patient's protein intake. Creatinine: To convert to mg/kg/24 hours, divide the mg/24 hour result by body weight in kg. CAUTIONS: Urine is often supersaturated with respect to the common crystalline constituents of stones, even in non-stone formers. Individual interpretation of the supersaturation values in light of the clinical situation is critical. In particular, treatment may reduce the supersaturation with respect to one crystal type but increase the supersaturation with respect to another. Therefore, the specific goals of treatment must be considered when interpreting the test results.