Activated Partial Thromboplastin Time (APTT)

Activated Partial Thromboplastin Time (APTT) is a coagulation blood test that assesses the intrinsic and common pathways of the clotting cascade. It evaluates the function of several clotting factors, including factors VIII, IX, XI, XII, and common pathway factors such as II, V, and X.

This test is commonly used to diagnose bleeding disorders like hemophilia, detect clotting factor deficiencies, and monitor patients receiving anticoagulant therapy such as heparin. APTT is also helpful before surgeries to assess bleeding risk and in evaluating unexplained bleeding or clotting episodes. Results are interpreted in relation to clinical findings and, when required, alongside other coagulation tests like PT/INR.