Editorial Office (South Asia)
Chapter Editors: Debarati Bhar, Shambo Samrat Samajdar, Tanuka Mandal, Sattik Siddhanta
How to Cite This Chapter: Don-Wauchope A, Chetty VT, Ivica J, Kavsak P, Khan WI, Lafreniere M, Nouri K, Solnica B. Activated Partial Thromboplastin Time (aPTT). McMaster Textbook of Internal Medicine. Kraków: Medycyna Praktyczna. https://empendium.com/mcmtextbook-sae/chapter/B78.1269.3.7.64. Accessed September 20, 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]
Activated partial thromboplastin time (aPTT) [P]
Reference range, target level, or decision threshold
26-40 s (depending on reagents used)!!!; LD
Interpretation of results
↑ Congenital or acquired deficiencies of fibrinogen and/or factors II, V, VIII (eg, hemophilia, von Willebrand disease), IX, XI, or XII; acquired inhibitors against factors VIII (acquired hemophilia A), IX, XI, or XII, high-molecular weight kininogen, or prekallikrein; vitamin K deficiency; liver diseases; DIC; hemodilution; lupus anticoagulant; anticoagulants (UFH, VKAs, direct thrombin inhibitors, direct factor Xa inhibitors)