N-Telopeptide, Cross-Linked, Urine
Ordering Recommendation
Quantitative Chemiluminescent Immunoassay
1-4 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
For monitoring therapy, a baseline specimen should be collected prior to initiation of therapy. Subsequent specimens for comparison should be collected at the same time of day as the baseline specimen.  
Second-morning void or 24-hour urine. Refrigerate during collection. Collect without preservative.  
Specimen Preparation
Transfer a 1 mL aliquot of urine from a well-mixed, second-morning void or 24-hour collection to an ARUP Standard Transport Tube. (Min: 0.5 mL)  
Storage/Transport Temperature
Unacceptable Conditions
Specimens contaminated with blood or extensive hemolysis.  
Ambient: 24 hours; Refrigerated: 1 week; Frozen: 2 years  
Reference Interval
Age Male Female
7-​9 years 167-​578 nM BCE/mM creatinine 201-​626 nM BCE/mM creatinine
10-​12 years 152-​505 nM BCE/mM creatinine 173-​728 nM BCE/mM creatinine
13-​15 years 103-​776 nM BCE/mM creatinine 38-​515 nM BCE/mM creatinine
16-​17 years 34-​313 nM BCE/mM creatinine 20-​144 nM BCE/mM creatinine
18 years and older 21-​83 nM BCE/mM creatinine
Premenopausal 17-​94 nM BCE/mM creatinine
Postmenopausal 26-​124 nM BCE/mM creatinine
Interpretive Data
NTx Units = nM BCE/mM creatinine

A decrease of 30-40% from the NTx baseline after three months of therapy is a typical response to anti-resorptive therapy.

NTx = Cross-linked N-telopeptide of Type I Collagen
BCE = Bone Collagen Equivalent
CPT Code(s)
Component Test Code*Component Chart Name
0020207Creatinine, Urine - per volume
0070061NTx, Urine (nM BCE/mM Creatinine)
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, contact interface support at interface.support@aruplab.com.
Cross References
  • Collagen Crosslinks
  • Cross-Linked N-Telopeptide
  • Crosslinked N-telopeptide of Type I Collagen
  • N-Telopeptide, Urine
  • NTx
  • NTX Creatinine
  • NTX Urine
  • Osteomark
  • Osteoporosis