title: Autoantibodies to coagulation factors: from pathophysiology to diagnosis and therapy.
abstract: Autoantibodies may develop against coagulation factors altering their function or promoting their rapid clearance. In non-congenitally deficient patients, they are usually in association with autoimmune diseases, malignancies, pregnancy or advanced age. The possible development of coagulation factor autoantibodies should be considered when a patient presents with bleeding symptoms without any prior bleeding diathesis. The most common disorder associated with coagulation factor autoantibodies is acquired factor VIII deficiency, which is characterized by hemorrhages involving soft tissues, muscles and skin; hemarthroses are less frequent than in the inherited form. Acquired deficiencies of von Willebrand factor and factor XIII due to autoantibodies are emerging conditions. Autoantibodies to the other coagulation factors may be associated with a wide spectrum of clinical manifestations ranging from minimal or no bleeding to life-threatening conditions. The diagnostic approach begins with global coagulation tests: prothrombin time (PT) and activated partial thromboplastin time (aPTT). In case of prolonged times, mixing studies (typically using normal plasma in a 1:1 proportion) should be performed. Specific factor and inhibitor assays, assessment of lupus anticoagulant and eventually enzyme immunoassays for specific anti-factor antibodies complete the evaluation. A prompt diagnosis of specific coagulation factor inhibitors is mandatory for starting an appropriate treatment aimed at overcoming the deficient factor, in case of bleeding, and, if possible, at the suppression of the autoantibody's production.
authors: Medicina Interna, Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milano, Italy. Electronic address: massimo.cugno@unimi.it.
authors: Massimo
authors: M
authors: Cugno
authors: Roberta
authors: R
authors: Gualtierotti
authors: Alberto
authors: A
authors: Tedeschi
authors: Pier Luigi
authors: PL
authors: Meroni
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001323:Autoantibodies / Q000276:immunology*; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D001778:Blood Coagulation Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D001779:Blood Coagulation Factors / Q000276:immunology*; D006470:Hemorrhage / Q000175:diagnosis / Q000276:immunology / Q000628:therapy; D006801:Humans
chemical_list: D001323:Autoantibodies; D001779:Blood Coagulation Factors
keywords: Acquired hemophilia; Acquired von Willebrand syndrome; Activated partial thromboplastin time; Bethesda assay; Coagulation factors; Prothrombin time