342 Review Article Page 1 of 10 Rare thrombophilic conditions Gian Luca Salvagno1, Chiara Pavan2, Giuseppe Lippi1 1Section of Clinical Biochemistry, University of Verona, Verona, Italy; 2Division of Geriatric Medicine, Mater Salutis Hospital, Legnago, Verona, Italy Contributions: (I) Conception and design: GL Salvagno; (II) Administrative support: None; (III) Provision of study materials or patients: None; (IV) Collection and assembly of data: GL Salvagno, C Pavan; (V) Data analysis and interpretation: All authors; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors. Correspondence to: Prof. Gian Luca Salvagno, MD, PhD. Sezione di Biochimica Clinica, Dipartimento di Neuroscienze, Biomedicina e Movimento, Università degli Studi di Verona, Ospedale Policlinico G.B. Rossi, Piazzale Scuro, 10, 37134 Verona, Italy. Email:
[email protected]. Abstract: Thrombophilia, either acquired or inherited, can be defined as a predisposition to developing thromboembolic complications. Since the discovery of antithrombin deficiency in the 1965, many other conditions have been described so far, which have then allowed to currently detect an inherited or acquired predisposition in approximately 60–70% of patients with thromboembolic disorders. These prothrombotic risk factors mainly include qualitative or quantitative defects of endogenous coagulation factor inhibitors, increased concentration or function of clotting proteins, defects in the fibrinolytic system, impaired platelet function, and hyperhomocysteinemia. In this review article, we aim to provide an overview on epidemiologic, clinic and laboratory aspects of both acquired and inherited rare thrombophilic risk factors, especially including dysfibrinogenemia, heparin cofactor II, thrombomodulin, lipoprotein(a), sticky platelet syndrome, plasminogen activator inhibitor-1 apolipoprotein E, tissue factor pathway inhibitor, paroxysmal nocturnal haemoglobinuria and heparin-induced thrombocytopenia.