Ordering Recommendation

Preferred test to measure bone resorption and monitor response to antiresorptive therapy (eg, bisphosphonates, hormone replacement therapy) in postmenopausal women and individuals with osteoporosis.

Mnemonic

CTX

Methodology

Quantitative Electrochemiluminescent Immunoassay

Performed

Sun - Sat

Reported

Within 24 hours

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Fasting specimen preferred.

Collect

Serum separator tube, lavender (K2 EDTA or K3 EDTA), pink (K2 EDTA). A morning specimen is preferred.

Specimen Preparation

Allow serum separator tube to sit for 15-20 minutes at room temperature for proper clot formation. Centrifuge and separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)

Storage/Transport Temperature

CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.

Unacceptable Conditions

Hemolyzed specimens. Green lithium heparin plasma

Remarks
Stability

After separation from cells: Ambient: 24 hours; Refrigerated: 48 hours; Frozen: 3 months

Reference Interval

Age
Female
Male
6 months-6 years 500-1800 pg/mL 500-1700 pg/mL
7-9 years 566-1690 pg/mL 522-1682 pg/mL
10-12 years 503-2077 pg/mL 553-2071 pg/mL
13-15 years 160-1590 pg/mL 485-2468 pg/mL
16-17 years 167-933 pg/mL 276-1546 pg/mL
18-29 years 238-1019 pg/mL
30-39 years 225-936 pg/mL
40-49 years 182-801 pg/mL
50-59 years 161-737 pg/mL
60-69 years 132-752 pg/mL
70 years or greater 118-776 pg/mL
Premenopausal 136-689 pg/mL
Postmenopausal 177-1015 pg/mL

Interpretive Data



Compliance Category

FDA

Note

Hotline History

N/A

CPT Codes

82523

Components

Component Test Code* Component Chart Name LOINC
0070415 C-Telopeptide, Beta-Cross-Linked, Serum 41171-0
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • Beta-CTx
  • B-Cross Laps
  • B-CTx
  • Beta-Cross Laps
  • bone resorption marker
  • C-Telopeptide
  • C-terminal collagen crosslinks
  • Carboxy terminal collagen crosslinks
  • Collagen C Telopeptide
  • Collagen Type I-C
  • Collagen Type I-C Telopeptide
  • CTx
C-Telopeptide, Beta-Cross-Linked, Serum