Informe de un caso de deficiencia del factor XII de la coagulación
Video Experimental Relacionado
Updated: Jan 18, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Background:
Coagulation factor XII (FXII) deficiency is a rare coagulation disorder, often incidentally detected during routine physical examinations, invasive procedures, or preoperative screenings, with no specific clinical manifestations. Here, we report a case of FXII deficiency.
Methods:
A 46-year-old female patient was found to have unexplained prolonged activated partial thromboplastin time (APTT) during routine preoperative testing, without clinical bleeding symptoms. We performed an APTT mixing study, anti-cardiolipin antibody (ACA) testing, anti-β2-glycoprotein 1 (anti-β2-GP1) antibody testing, lupus anticoagulant (LA) screening, and coagulation factor assays to determine the cause of APTT prolongation.
Results:
The APTT mixing study showed correction result. Coagulation factor assays revealed significantly reduced FXII activity (0.1%), while factors XI, X, II, VIII, IX, V, and VII levels were elevated. ACA (IgA/IgG/IgM) and anti-β2-GP1 antibodies (IgA/IgG/IgM) were negative. LA testing by dilute Russell's viper venom time (dRVVT) was negative, and the silica clotting time (SCT) suggested factor deficiency rather than an inhibitor. These findings confirmed that the patient's prolonged APTT was due to FXII deficiency.
Conclusions:
When prolonged APTT is observed in a patient without bleeding symptoms, laboratory personnel should consider the possibility of FXII deficiency.
Videos de Conceptos Relacionados
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
Coagulation
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...
Coagulation
Venous Thrombosis III: Interprofessional Care

