Collagen Cross-Linked N-Telopeptide (NTx), Urine

Test Code

NTx

Quest Code

36167

Alias/See Also

N-Telopeptide Cross Link

CPT Codes
82523, 82570

Includes

Creatinine

Preferred Specimen

2 mL unpreserved urine collected from second morning void

Minimum Volume

1 mL

Other Acceptable Specimens

Unpreserved random urine • Unpreserved catheterized urine • Unpreserved first void clean catch urine

Instructions

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

Frozen

Specimen Stability

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

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Acidified specimen • Preserved specimen

Methodology
Chemiluminescence (CL)

Setup Schedule

Set up: Mon, Wed, Fri; Report available: 3-6 days

Reference Range

Collagen Cross-Linked N-Telopeptide (NTx), Random Urine

Male
18-29 Years	12-99 nM BCE/mM creat
30-59 Years	9-60 nM BCE/mM creat
Female
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
33608 Ortega Highway
San Juan Capistrano, CA 92690-6130

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.