Collagen Cross-Linked N-Telopeptide (NTx), Urine [36167]

For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

Test Code

Alias/See Also
Collagen Cross (urine);
N-Telopeptide (urine);
NTX (urine)

CPT Codes
82523, 82570


Preferred Specimen
2 mL urine from second morning void submitted in a leak-proof container, no preservative

Minimum Volume
1 mL

Other Acceptable Specimens
Random urine, catheterized, or first morning void clean catch, submitted in a leak-proof urine container, no preservative

Do not use preservatives. Acidified specimen is not acceptable. Second morning void urine: Discard the first morning void. Collect the second morning void. Mix well.

Transport Temperature
Refrigerated (cold packs)

Specimen Stability
Room temperature: 72 hours
Refrigerated: 5 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Acidified specimen • Preserved specimen

Chemiluminescence (CL)

Setup Schedule
Set up: Mon-Sat; Report available: 1-2 days

Reference Range
Collagen Cross-Linked N-Telopeptide (NTx), Random Urine
  18-29 Years 12-99 nM BCE/mM creat
  30-59 Years 9-60 nM BCE/mM creat
  Premenopausal 4-64 nM BCE/mM creat
Results are primarily used for monitoring the response to therapy. A value within the premenopausal reference range does not rule out osteoporosis nor the need for therapy.

Creatinine, Random Urine
≤6 Months 2-28 mg/dL
7-11 Months 2-31 mg/dL
1-2 Years 2-110 mg/dL
3-8 Years 2-130 mg/dL
9-12 Years 2-160 mg/dL
>12 Years Male 20-320 mg/dL
>12 Years Female 20-275 mg/dL

Clinical Significance
NTx is useful to assess bone resorption in patients with metabolic bone disease. The test is also useful in monitoring therapy to slow or halt osteoporotic bone loss. A decline of 30% or more of NTx over a six-month period suggests effective therapy.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

Last Updated: November 29, 2021

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.