N-Telopeptide, Cross-Linked
Label Mnemonic: NTP
Epic Lab Code: LAB3729
Downtime Form: A-1a Miscellaneous Request
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
Specimen Instructions:
Refrigerate during 24 hr collection in plastic container.

Patient Prep: For monitoring therapy, a baseline sample should be collected prior to initiation of therapy. Subsequent samples for comparison should be collected at the same time of day as the baseline sample.
Collection Medium:
Urine - 24 hour/timed plastic urine container
Minimum:
Preferred Minimum: 1.0 mL
Absolute Minimum 0.5 mL

Collect second morning void or 24 hr urine. Sample must be refrigerated during collection and submission to laboratory. No preservative.
Rejection Criteria:
Specimens contaminated with blood or having extensive hemolysis.
Turn Around Time:
1-4 days upon receipt at reference laboratory
Reference Range:
Age Male Female 7-9 yrs 167-578 nM BCE/mM creatinine 201-626 nM BCE/mM creatinine 10-12 yrs 152-505 nM BCE/mM creatinine 173-728 nM BCE/mM creatinine 13-15 yrs 103-776 nM BCE/mM creatinine 38-515 nM BCE/mM creatinine 16-17 yrs 34-313 nM BCE/mM creatinine 20-144 nM BCE/mM creatinine 18 yrs & 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
Methodology:
Quantitative Chemiluminescent Immunoassay
CPT Code:
82523