Alternative titles and symbols : Rosenthal syndrome; Plasma thromboplastin antecedent deficiency; F11 deficiency; Pta deficiency;
Description : Factor XI deficiency is an autosomal bleeding disorder characterized by reduced levels
of factor XI in plasma (less than 15 IU/dL). Bleeding occurs mainly after trauma or
surgery. On the basis of the concordance or discordance of F11 antigen and activity,
the disorder is classified into the more frequent cross-reactive negative (CRM-) and
the rarer CRM positive (CRM ) (summary by Duga and Salomon, 2009).;