title: A case of chronic myelomonocytic leukaemia and factor XI deficiency with a circulating anticoagulant.
abstract: Inhibitors against factor XI (FXI) have been frequently described in patients who acquired inhibitors (due to auto-immune disorders, malignancies or infections), but less often in those with a congenital deficiency of this factor, who had received plasma infusions. The present report concerns one such inhibitor found in the plasma of a patient with chronic myelomonocytic leukaemia and infected by B19 parvovirus, who was neither a heterozygote nor a homozygote for FXI deficiency, and who had no bleeding tendency despite a very low FXI level. Taking this case into account, we discuss and present the clinical and biological features of acquired FXI deficiency caused by an inhibitor.
authors.affiliation: Clinical Department of Hematology, Hôpital Morvan, Brest, France Laboratory of Hematology, Hôpital Morvan, Brest, France. sandrine.billon@univ-brest.fr
authors.forename: S
authors.initials: S
authors.lastname: Billon
authors.forename: M T
authors.initials: MT
authors.lastname: Blouch
authors.forename: M
authors.initials: M
authors.lastname: Escoffre-Barbe
authors.forename: C
authors.initials: C
authors.lastname: Le Niger
authors.forename: A M
authors.initials: AM
authors.lastname: Le Roux
authors.forename: J F
authors.initials: JF
authors.lastname: Abgrall
mesh_terms: D000368:Aged; D001323:Autoantibodies / Q000276:immunology; D005172:Factor XI / Q000276:immunology*; D005173:Factor XI Deficiency / Q000097:blood / Q000276:immunology; D005260:Female; D006801:Humans; D015477:Leukemia, Myelomonocytic, Chronic
chemical_list: D001323:Autoantibodies; D005172:Factor XI