Beta Crosslaps

The human body constantly undergoes the process of formation and resorption during which bones are remodeled. Around 90% of a bone's organic matrix comprises Type I collagen. During the bone remodeling process, osteoclast cells release a mixture of neutral and acidic enzymes that break down the collagen into molecules, including C-terminal telopeptide (CTx).

As bones age, the amino acids present in CTx change their chemical composition from Alpha to Beta. When that occurs, the bone remodeling process releases Beta-CTx into the bloodstream, which is indicative of Type I collagen degradation.

Increased concentrations of Beta-CTx in the blood indicate an overactive bone remodeling process in the body. Such abnormalities in bone turnover can result in:

• Change in skeletal mass and bone density
• Bone deformation

Some common conditions that are associated with unusual bone turnover include the following:

• Hyperthyroidism
• All forms of hyperparathyroidism
• Osteomalacia (softening of the bone)
• Paget disease
• Multiple myeloma (Plasma Cell Cancer)
• Bone metastasis (Spread of cancer cells to a bone)

Besides these bone-related diseases, post-menopausal osteopenia (loss of bone density after menopause) and osteoporosis (brittle bones) can also lead to an overactive resorption process.

Bone resorption can also occur around a patient’s mouth or jaw. Some common symptoms of this particular type include the following:

• Swelling of gums
• Pain in the crown, root or internal space in a tooth
• Brittle teeth 
• Gum discolouration

A Beta Cross Laps (B-CTx test) helps to determine a subject’s bone turnover rate. Specific markers discovered during the test can help detect bone diseases or be used to supplement tests for bone density.

The test is performed through a Roche Cobas 6000 e601 analyzer. Labeled with ruthenium, the patient’s specimen reacts to form a complex. Voltage is then applied to the electrode, after which it's measured against a calibration curve. That measurement reveals the amount of B-CTx present in the patient specimen.

A B-CTx test can also be used to outline treatment options for bone-related diseases. In the case of adults, the test can be used for the following:

Monitoring response to anti-resorptive therapies such as hormone replacement and bisphosphonates
Measuring the effectiveness of drug dosage

For children, the test can be used to detect and manage the following conditions:

• Metabolic bone disorders
• Paget disease
• Rickets
• Secondary osteoporosis

With the help of a B-CTx test, specific bone turnover abnormalities can be treated with timely intervention. Consistent monitoring of urine and serum markers can be used to determine any changes in a patient’s subsequent bone turnover rate.

An effective way to keep bone resorption under check is to exercise regularly. It's also essential to avoid high doses of Vitamin D supplements. Previous studies have indicated that excessive Vitamin D can lead to an accelerated turnover rate. To manage this, patients must moderate Vitamin D intake with calcium supplements.

In the case of facial bone breakdown, it’s possible to minimize the effects of dental implants. In extreme cases, bone grafting may be necessary.

Apollo 24|7 offers a comprehensive B-CTx test that can be a diagnostic tool to determine any pre-existing bone-related issues in the patient.
 

Medically reviewed by Dr. Kosygan K P, Orthopaedics, Apollo Hospitals Greams Road, Chennai.