What is lupus anticoagulant?
Lupus anticoagulant is an IgM or IgG antibody that produces a prolong plasma thromboplastin time (PTT) assay in vitro resulting in an artificially long protime. Clinically, this does not result in a bleeding disorder. Instead, lupus anticoagulant has been associated with an increased risk of thrombosis and recurrent spontaneous fetal loss1. Therefore, the name lupus anticoagulant is considered a misnomer. Lupus anticoagulant should be suspected in patients with remarkably prolonged PTT without any clinical bleeding. However, bleeding can occur if a secondary disorder is present. Patients do not need to be diagosed with lupus in order to have lupus anticoagulant. Only 5-10% of patients with systemic lupus erythematosus have lupus anticoagulant. It is much more commonly seen in patients without any underlying disorders but who continue having recurrent throbosis events or in patients who are taking phenothiazines1. How is lupus anticoagulant detected in patients? According to Proven et a
