Cystine, Random Urine with Creatinine
Test Code
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 ...
Test Resources
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Test Details
Methodology
Reference Range(s)
| 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 |
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
Setup Schedule
Do not thaw. Patient age is required for correct reference range.
Refrigerated: Frozen only
Frozen: 28 days