RENAL STONE PROFILE

Mnemonic

RSTNP

Synonym

Stone Profile - Stone Profile, Renal

Includes

Serum or Plasma: Glucose, Calcium, Phosphorus, BUN, Sodium, Potassium, Creatinine, Chloride, Albumin, Uric Acid, Cholesterol, Total CO2

Timed Urines: Urine Calcium, Urine Uric Acid, Urine Magnesium, Urine Creatinine, Urine Urea Nitrogen, Urine Oxalate, Urine Citrate, Urine Sodium, Urine Calcium/Creatinine ratio

Specimen Collection Requirements

Patient Preparation

Patient should avoid ingestion of vitamin C prior to collection (Oxalate).

Collect

Serum or Plasma, one 5.0 mL gold (SST), 7.0 mL red, or 3.0 mL mint green (PST) top tube. Timed Urine, one 12 or 24 hour collection in a sterile container.

Patient Instructions for Collecting a Timed Urine Sample (24, 48, 72 hours)

Handling

Both urine and serum or plasma are required.

Serum or Plasma: Allow serum to clot completely at room temperature (minimum: SST - 30 minutes and red top tubes – 60 minutes). Preferably, separate serum or plasma from cells before transport.

Timed Urine: Refrigerate urine specimen during collection. To properly aliquot sample: 1) Thoroughly mix entire urine collection in one container; 2) Remove a 20.0-30.0 mL aliquot and refrigerate; 3) Remove a 4.0 mL aliquot and freeze for oxalate.  Record total volume of timed urine and urine collection time interval on container(s) and test request form.

Preferred Volume

Serum or Plasma: 1.0 mL, Urine: 20.0 mL 

Minimum Volume

Serum or Plasma: 0.5 mL (1.2 mL minimum whole blood draw)

Urine: 4.5 mL

Transport

Urine Oxalate: Frozen (≤-20°C)

All other testing: Refrigerated (2-8°C)

Rejection Criteria

Grossly hemolyzed specimens, urine specimens exposed to room temperature (18-26°C) for greater than 2 hours

Stability

SERUM/PLASMA AFTER SEPARATION FROM CELLS: Room Temperature (18-26°C): 8 hours; Refrigerated (2-8°C): 3 days; Frozen (≤-20°C): 1 month

URINE: Urine oxalate must be frozen ASAP.

OTHER URINE TESTS: Room Temperature (18-26°C): 2 hours; Refrigerated (2-8°C): 3 days; Frozen (≤-20°C): Unacceptable

Testing Information

Performed

LEGACY: 7 days/week, Urine Oxalate (ARUP): Mon - Fri, Urine Citrate (ARUP): 7 days/week

Reported

LEGACY: 24 hours ARUP: 1-4 days

Method

See specific test.

Referral Lab

ARUP: Urine Oxalate (20482), Urine Citrate (20852)

Reference Values

Reference Values

Interpretive guidelines provided with the report.

Comments

Legacy Referral Department will adjust the pH to 1.5-2 with 6M HCl for ARUP Labs (Urine Oxalate and Urine Citrate).

 

Refer to specific tests for interferences.

CPT Codes

U Calcium: 82340, U Citric Acid: 82507, U Creatinine: 82570, U Magnesium: 83735, U Oxalate: 83945, U Sodium: 84300, U Urea: 84540, U Uric Acic: 84560, Renal Function: 80069, Uric Acid: 84550, Cholesterol: 82465

Last Updated: Thursday, January 5, 2017 03:42:27 AM