What are other Names for this Test? (Equivalent Terms)
- NTx Urine Test
What is N-Telopeptide Cross-Links Urine Test? (Background Information)
- N-Telopeptide cross-links (NTx) are protein fragments created as a result of bone breakdown. NTx is used as a marker for bone degradation in disorders such as osteoporosis and osteopenia
- Bone is made up of bone cells separated by bone matrix. About 90% of bone matrix is comprised of collagen, which has been cross-linked to make it stronger. The remaining components are inorganic salts such as bone mineral (hydroxyapatite)
- Bone degradation causes the breakdown of these collagen fibers, which forms the telltale NTx fragments. The bone degradation is also carried out naturally by cells called osteoclasts. It occurs when calcium reserves are low, and as a normal part of bone maintenance and repair
- Bone degradation is accelerated during conditions, such as osteoporosis and osteopenia, along with other bone disorders. NTx levels are significantly elevated in these cases
- The N-Telopeptide Cross-Links Urine Test helps determine the levels of NTx in urine. It aids in the diagnosis of bone disorders such as osteoporosis
What are the Clinical Indications for performing the N-Telopeptide Cross-Links Urine Test?
Following are the clinical indications for performing the N-Telopeptide Cross-Links Urine Test:
- Monitoring the effects of antiresorptive therapy
- Frequent and/or unusual bone fractures
- Loss of height
- Hair loss
- Brittle nails
- Developmental issues, such as delayed onset of puberty
How is the Specimen Collected for N-Telopeptide Cross-Links Urine Test?
Following is the specimen collection process for N-Telopeptide Cross-Links Urine Test:
Sample required: Urine
Process of obtaining a sample in adults: Urination into a sterile container over a 24-hour period.
Preparation required: It is recommended to drink 6 to 8 glasses of water or other fluids prior to the test.
What is the Significance of the N-Telopeptide Cross-Links Urine Test Result?
The following is the significance of the N-Telopeptide Cross-Links Urine Test:
- A high value, greater than 65 mM BCE/mmol creatinine in women and 51 mM BCE/mmol creatinine in men, for the test may point to a diagnosis of the following conditions:
- Paget’s disease
- Advanced bone tumors
- A low value, less than 5 mM BCE/mmol creatinine in women and 3 mM BCE/mmol creatinine in men, for the test may point to a diagnosis of the following conditions:
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.
The following DoveMed website link is a useful resource for additional information:
Please visit our Laboratory Procedures Center for more physician-approved health information: