Test Code KIDST Kidney Stone Analysis
Necessary Information
Specimen source is required.
Specimen Required
Supplies: Stone Analysis Collection Kit (T550)
Sources: Bladder, kidney, prostatic, renal, or urinary
Specimen Volume: Entire dried calculi specimen
Collection Instructions:
1. Have patient collect specimen using the Patient Collection Instructions for Kidney Stones.
2. For detailed instructions on kidney stone preparation and packaging, see Kidney Stone Packaging Instructions.
3. Prepare stone by cleaning any blood or foreign material from the stone with deionized water.
4. Place stone on a clean filter or paper towel and let dry at ambient temperature for a minimum of 24 hours.
5. Do not place stone directly in a bag. If specimen is received in a bag, either transfer stone into a screw-capped, plastic container or place bag containing stone in a screw-capped, plastic container.
6. Indicate source of specimen on the outside of the container (eg, left kidney, bladder, right ureter).
7. Repeat steps 2 through 5 for each stone received.
Specimen Stability Information: Ambient (preferred) 2 years/Refrigerated 1 year/Frozen 1 year
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
-Renal Diagnostics Test Request (T830)
Useful For
Managing patients with recurrent renal calculi (kidney stones)
Special Instructions
Method Name
Infrared Spectrum Analysis
Reporting Name
Kidney Stone AnalysisSpecimen Type
StoneSpecimen Minimum Volume
Entire stone
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Stone | Ambient (preferred) | ||
Frozen | 365 days | ||
Refrigerated | 365 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
The composition of urinary stones may vary from a simple crystal to a complex mixture containing several different species of crystals. The composition of the nidus (center) may be entirely different from that of the peripheral layers.
Eighty percent of patients with kidney stones have a history of recurrent stone formation. Knowledge of stone composition can be useful to guide therapy of patients with recurrent stone formation.
Treatment of urinary calculi is complex.(1) In an overly simplified format, the following patterns are often treated as follows:
-Hyperuricuria and predominately uric acid stones: Alkalinize urine to increase uric acid solubility
-Hypercalciuria and predominately hydroxyapatite stones: Acidify urine to increase calcium solubility
However, treatment also depends on urine pH and urine phosphate, sulfate, oxalate, and citrate concentrations.
-Hyperoxaluria and calcium oxalate stones: Increase daily fluid intake and consider reduction of daily calcium
However, daily requirements for calcium to maintain good bone formation complicate the treatment.
-Magnesium ammonium phosphate stones (struvite): Investigate and treat urinary tract infection.
Reference Values
The presence of a kidney stone is abnormal. A quantitative report will be provided after analysis.
Day(s) Performed
Monday through Saturday
Report Available
4 to 6 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82365