{"id":"ctx","name":"CTX (C-Telopeptide of Type I Collagen), Serum","shortName":"CTX","aliases":["CTX","C-Telopeptide","Beta-CrossLaps","Collagen Type I C-Telopeptide","CTX-1","C-Terminal Telopeptide","Beta-CTX","C-Telopeptide, Beta Cross-Linked","Collagen Type I C-Telopeptide (CTx)","C-Telopeptide, Beta-Cross-Linked, Serum","Serum CTX","Serum C-Telopeptide","CTx","β-CTX","β-CrossLaps","Serum CrossLaps","CTX-I","Beta Cross Laps","Collagen Type 1 Cross-Linked C-Telopeptide"],"abbreviations":["CTX","CTX-I","CTx","β-CTX"],"loinc":[{"code":"41171-0","primary":true},{"code":"53092-3","primary":false}],"specimen":"serum-or-plasma","units":[{"ucum":"pg/mL","display":"pg/mL"},{"ucum":"ng/L","display":"ng/L"},{"ucum":"ng/mL","display":"ng/mL"},{"ucum":"ug/L","display":"µg/L"}],"referenceRanges":[{"population":"Men, 18–29","low":238,"high":1019,"unit":"pg/mL","unitDisplay":"pg/mL","note":"ARUP Laboratories' interval for men 18 to 29 (electrochemiluminescence immunoassay). Quest prints different limits for the same group (87-1,200 pg/mL for men 18 to 29, 70-780 for 30 to 39, 60-700 for 40 to 49 and 87-345 for 50 to 68), because assays and reference groups differ. Use the range printed on your own report. pg/mL and ng/L are the same number.","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"}]},{"population":"Men, 30–39","low":225,"high":936,"unit":"pg/mL","unitDisplay":"pg/mL","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"}]},{"population":"Men, 40–49","low":182,"high":801,"unit":"pg/mL","unitDisplay":"pg/mL","note":"ARUP's interval matches the Danish Roche-assay reference intervals for men 40-49 (182-801 ng/L) and 50-59 (161-737 ng/L) in the Schini 2023 review.","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"},{"title":"Bone Turnover Markers: Basic Biology to Clinical Applications","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC10166271/","publisher":"Endocrine Reviews","year":2023}]},{"population":"Men, 50–59","low":161,"high":737,"unit":"pg/mL","unitDisplay":"pg/mL","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"},{"title":"Bone Turnover Markers: Basic Biology to Clinical Applications","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC10166271/","publisher":"Endocrine Reviews","year":2023}]},{"population":"Men, 60–69","low":132,"high":752,"unit":"pg/mL","unitDisplay":"pg/mL","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"}]},{"population":"Men, 70+","low":118,"high":776,"unit":"pg/mL","unitDisplay":"pg/mL","sources":[{"title":"C-Telopeptide, Beta-Cross-Linked, Serum (test 0070416)","url":"https://ltd.aruplab.com/Tests/Pub/0070416","publisher":"ARUP Laboratories"}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A blood marker of how fast old bone is being broken down. It is mostly used to follow osteoporosis treatment, not to screen healthy people.","url":"https://bloodtesttracker.com/markers/ctx","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}