Sign in →

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)

Secondary ID

605761

Useful For

Managing patients with recurrent renal calculi (kidney stones)

Testing Algorithm

Upon arrival in the performing laboratory, all stone specimens and the containers in which they are received will be inspected. Prior to analysis, stones must be clean and dry.

Method Name

Infrared Spectrum Analysis

Reporting Name

Kidney Stone Analysis

Specimen Type

Stone

Specimen 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.

Cautions

No significant cautionary statements

Day(s) Performed

Monday through Saturday

Report Available

4 to 6 days

Specimen Retention Time

7 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test 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

LOINC Code Information

Test ID Test Order Name Order LOINC Value
KIDST Kidney Stone Analysis 74446-6

 

Result ID Test Result Name Result LOINC Value
605761 Kidney Stone Analysis 40787-4
SRC1 Source: 31208-2
605762 Stone Interpretation 56119-1
618163 Result Comment 77202-0