How to Cite This Chapter: Don-Wauchope A, Chetty VT, Ivica J, Kavsak P, Khan WI, Lafreniere M, Nouri K, Solnica B. Antithrombin (AT) Function. McMaster Textbook of Internal Medicine. Kraków: Medycyna Praktyczna. https://empendium.com/mcmtextbook/chapter/B31.1269.3.7.45. Accessed November 03, 2024.
Last Updated: May 9, 2022
Last Reviewed: May 9, 2022
Chapter Information
McMaster Textbook of Internal Medicine Editorial Offices
Editorial Office (Canada)
Authors: Andrew Don-Wauchope, Vasudhevan T. Chetty, Joško Ivica, Peter Kavsak, Waliul I. Khan, Matthew Lafreniere, Kazem Nouri
Editorial Office (Poland)
Authors: Bogdan Solnica
For a brief introduction and guide to abbreviations, see Laboratory Tests: General Remarks.
Analyte [material]
Antithrombin (AT) function [P]
Reference range, target level, or decision threshold
0.83-1.28 U/mL!!!; LD
AT immunoassay is also available as a specialty test.
Interpretation of results
↑ or falsely normal with direct factor Xa inhibitors for anti-Xa AT assays or with direct thrombin inhibitors for anti-IIa AT assays
↓ Congenital antithrombin deficiency, consumptive states (eg, acute thrombosis, DIC, sepsis), liver disease, nephrotic syndrome, malnutrition, protein-losing enteropathies, pregnancy, UFH treatment