Factor XI Deficiency.
ABSTRACT Severe factor XI (FXI) deficiency is an injury-related bleeding disorder common in Ashkenazi Jews and rare worldwide. In the past two decades, more than 180 mutations in the FXI gene have been reported in patients with FXI deficiency, five of which show a founder effect (Cys38Arg, Gln88Stop, Cys128Stop, Glu117stop, and Phe283Leu, the last two largely prevalent among Ashkenazi Jews). Inhibitors to FXI after exposure to plasma, FXI concentrates, or Rh immunoglobulin were described in patients with mutations resulting in null alleles. Treatment with low-dose recombinant activated factor VII in these patients appears promising. Survival advantages to patients with severe FXI have been recently reported. Herein, we present new observations related to clinic presentation, genotype-phenotype correlation, and treatment problems in patients with FXI deficiency.
Article: A novel missense mutation Asp506Gly in Exon 13 of the F11 gene in an asymptomatic Korean woman with mild factor XI deficiency.[show abstract] [hide abstract]
ABSTRACT: Factor XI (FXI) deficiency is a rare autosomal recessive coagulation disorder most commonly found in Ashkenazi and Iraqi Jews, but it is also found in other ethnic groups. It is a trauma or surgery-related bleeding disorder, but spontaneous bleeding is rarely seen. The clinical manifestation of bleeding in FXI deficiency cases is variable and seems to poorly correlate with plasma FXI levels. The molecular pathology of FXI deficiency is mutation in the F11 gene on the chromosome band 4q35. We report a novel mutation of the F11 gene in an 18-year-old asymptomatic Korean woman with mild FXI deficiency. Pre-operative laboratory screen tests for lipoma on her back revealed slightly prolonged activated partial thromboplastin time (45.2 sec; reference range, 23.2-39.4 sec). Her FXI activity (35%) was slightly lower than the normal FXI activity (reference range, 50-150%). Direct sequence analysis of the F11 gene revealed a heterozygous A to G substitution in nucleotide 1517 (c.1517A>G) of exon 13, resulting in the substitution of aspartic acid with glycine in codon 506 (p.Asp506Gly). To the best of our knowledge, the Asp506Gly is a novel missense mutation, and this is the first genetically confirmed case of mild FXI deficiency in Korea.The Korean Journal of Laboratory Medicine 10/2011; 31(4):290-3. · 0.63 Impact Factor