Cystine, Random Urine with Creatinine

Test code

401

CPT code(s)*

82131, 82570

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide Service Area Information to find available tests you can order.

In-home collection is not available in your area through Quest Mobile.

Clinical significance

Cystine, Random Urine with Creatinine - This quantitative test may be useful for evaluation of individuals with clinically suspected cystinuria, including those with symptoms of kidney stones or cystine crystals detected in urinalysis [1]. Although 24-hour urine testing is generally preferred for diagnostic evaluation and monitoring of cystinuria [2], random or first-morning void urine collection may be helpful for diagnosis when 24-hour urine collection is not feasible (eg, for young children) [3].Cystinuria, an autosomal recessive genetic disorder that can cause kidney stones, is characterized by excessive excretion of cystine and dibasic amino acids in the urine. Around 1% to 2% of…

Test resources

None found for this test
Please visit our Clinical Education Center to stay informed on any future publications, webinars, or other education opportunities.

Details

Test details

Includes

Creatinine

Methodology

Liquid Chromatography/Mass Spectrometry (LC/MS)

Assay category

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Specimen requirements
Patient preparation	None Specified
Preferred specimen(s)	1.8 mL random urine collected in a sterile screw-cap container
Alternative specimen(s)	Catheterized urine • First void clean catch urine • Random clean catch urine
Minimum volume	0.6 mL
Collection instructions	Do not use preservatives. Urine with a pH <2.0 will be rejected. Do not thaw. Patient age is required for correct reference range.
Transport container	Transport tube
Transport temperature	Frozen
Specimen stability	Room temperature: Frozen only Refrigerated: Frozen only Frozen: 28 days
Reject criteria	Received room temperature • Received refrigerated • Received thawed • pH <2.0

Reference range(s)

Reference Range(s)

Cystine

Pediatric (<18 Years)			3.2-12.6 mmol/mol creat
Adult			3.4-16.4 mmol/mol creat

Creatinine, Random Urine

0-6 Months	0.18-2.48 mmol/L
7-11 Months	0.18-2.74 mmol/L
1-2 Years	0.18-9.72 mmol/L
3-8 Years	0.18-11.49 mmol/L
9-12 Years	0.18-14.14 mmol/L
>12 Years	1.77-23.31 mmol/L

LOINC® codes

Select a service areato view this section

Service Area Information

Performing lab & setup schedule

Select a service areato view this section

Service Area Information

Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.

*The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

This material contains content from LOINC® (http://loinc.org). The LOINC Table, LOINC Table Core are copyright © 1995-2019, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license.

The tests listed by specialty and category are a select group of tests offered. For a complete list of Quest Diagnostics tests, please adjust the filter options chosen, or refer to our Directory of Services.

Customize the test information for your service area