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Results for “Factor XI Deficiency”

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PubMed1980

Immunoquantitation of Hageman factor in urine and plasma of children with nephrotic syndrome.

Children with nephrotic syndrome frequently have decreased plasma levels of Hageman factor (factor XII). Studies were designed to determine whether this finding results primarily from a loss of Hageman factor in the urine or is related to an alteration in the Hageman factor protein itself. A monospecific anti-Hageman factor goat antibody was prepared and used for quantitative measurements of Hageman factor in urine and plasma by a radial immunodiffusion method. Samples of 24 hr urine collections from 14 children with nephrotic syndrome were examined by this immunoassay technique; no Hageman factor was detected in the urine in 13/14 patients. Comparative studies using plasma from the nephrotic syndrome patients and nine normal controls demonstrated: (1) a significantly reduced level of Hageman ACT in the nephrotic syndrome patients (p < 0.001); (2) a reduction to a lesser degree of the levels of CRM in the same group (p < 0.001); and (3) a significantly increased CRM/ACT ratio in the plasma of the patients with nephrotic syndrome (p < 0.01) indicating partial inactivation of the Hageman factor enzymatic function. However, no inhibitory activity to added Hageman factor could be detected in the plasma or urine of the patients. These findings indicate that the decreased plasma Hageman factor activity that accompanies the nephrotic syndrome cannot be adequately explained by simple urinary loss of Hageman factor as has previously been suggested.

Adolescent↗
PubMedDate not supplied

Undiagnosed bleeding states and medical treatment.

Relatively little attention has been placed in mild hemophilia in the orthopedic literature even though there are probably an equal number of patients with mild as compared to classic manifestations. Mild hemophilia and similar related conditions frequently are undiagnosed and may represent major problems and if associated with surgery, catastrophic results. Patients with milder bleeding diatheses may not have a diagnosis made until late in life. Mild hemophilia and hemophiloid conditions are defined and typical findings are given. Other causes of intra or postoperative hemorrhagic states are mentioned. Three case reports of mild Factor VIII and Factor XI deficiency, undiagnosed prior to the author's medical treatment, are presented. Knowledge of the typical historical findings, diagnostic methods, and proper treatment of patients seeking medical treatment with mild hemophilia, hemophiloid and similar conditions explaining hemorrhage following trauma and intra and postoperatively will help to prevent undesirable results as well as severe complications.

Adult↗
PubMed1977

Demonstration and mode of action of an inhibitor for activated Hageman factor (factor XIIa) of the intrinsic blood coagulation pathway from Schistosoma mansoni.

An anticoagulant activity from adult Schistosoma mansoni whole worm homogenate is described. The inhibitor appears to be specific for the contact activation step of the intrinsic pathway. Experiments with both human and mouse plasmas have defined the specificity of the inhibitor as follows: (1) It lengthens the partial thromboplastin time of normal plasma. (2) It has no effect on the prothombin time and Russell's viper venom time of normal plasma. (3) Preactivation of normal plasma by a contact activator such as Celite eliminates essentially all inhibitory activity. (4) The inhibitor appears to be heat stable and can be precipitated by centrifugation above 27,000 g. (5) The inhibitor has no effect on the activation of factor XII by Celite. (6) The activation of factor XI by factor XIIa, however, is inhibited by the schistosomal inhibitor. The above data are consistent with the view that S. mansoni adults possess an anticoagulant that is capable of specifically inhibiting the conversion of factor XI to factor XIa by factor XIIa.

Animals↗
PubMed1998

Assessment of Actin FS and Actin FSL sensitivity to specific clotting factor deficiencies.

We present a two centre study designed to assess the sensitivity of Actin FS and Actin FSL to deficiencies of factor VIII, IX, XI or XII. The study was undertaken at two centres to avoid bias due to the investigations being undertaken on one analyser. Samples from patients with a factor VIII (n = 36, F VIII = < 1.0-50 iu/dl), factor IX (n = 22, F IX = 2-48 iu/dl), factor XI (n = 23, F XI = 5-50 u/dl) or a factor XII (n = 18, F XII = 1-50 u/dl) deficient state were studied. Activated partial thromboplastin times (APTT) were determined using two batches of Actin FS and of Actin FSL; comparison of APTT results between centres was facilitated by the conversion of clotting times to ratios (test divided by geometric mean normal clotting time). APTT ratios were considered to be elevated if greater than two standard deviations above the mean normal. The factor deficient status of each sample was verified by assaying all samples for factors VIII, IX, XI and XII. Clotting factor assays were performed on a Sysmex CA-1000 fitted with research software, which permitted the auto-dilution and testing of three serial dilution of both a reference preparation and each patient's sample. Assay results were calculated using parallel-line Bioassay principles. This procedure allowed for variation in clotting times due to the effect of temporal drift of any of the reagents within the assay system. Actin FS and Actin FSL demonstrate acceptable sensitivity to factor VIII deficiency, however, both reagents failed to detect a large proportion of factor XI (17.4% and 30.4% of samples, respectively) and factor XII (66.7% and 72.2%, respectively) deficiencies. The detection rate with Actin FSL for factor IX deficiency was also poor (36.4% not detected). As factor IX and XI deficiencies are both associated with haemorrhagic disorders, the inability of these reagents to detect such abnormalities gave cause for concern.

Actins↗
PubMed1988

Hereditary plasma thromboplastin antecedent (PTA, FXI) deficiency in a Saudi family.

A rare case of factor XI (PTA) deficiency was discovered in a Saudi family in the Riyadh area. Nine members of the family were studied. Two were found to have a severe PTA deficiency; levels of factor XI clotting activity were 0.01 i.u./ml and 0.02 i.u./ml respectively. Both plasmas were markedly deficient in factor XI antigen and appeared to be negative for cross-reactive material (CRM-). The parents were first cousins and both were found to have a minor PTA deficiency. Factor XI levels were: mother 0.048 i.u./ml and father 0.33 i.u./ml. Another sibling was found to have a FXI level of 0.47 i.u./ml. Menorrhagia and bleeding for 1 day after tooth extraction were the main bleeding manifestations found in one member with severe PTA deficiency. Clinically this member presented with iron deficiency anaemia. Other family members had no significant history of bleeding tendency. This is the first report of a Saudi Arabian family with PTA deficiency.

Adolescent↗
PubMed1985

Failure to detect variant (CRM+) plasma thromboplastin antecedent (factor XI) molecules in hereditary plasma thromboplastin antecedent deficiency: a study of 125 patients of several ethnic backgrounds.

Plasma samples of 125 patients from 80 kindreds with hereditary plasma thromboplastin antecedent (PTA, factor XI) deficiency were tested by factor XI radioimmunoassay (RIA) and electroimmunoassay (EIA) in an attempt to detect variant molecules. Ninety-six patients (70 kindreds) were Jewish, and 29 (10 kindreds) were of other ethnic backgrounds, namely, Japanese, black American, Korean, Arab, Indian, and English. Seventy-eight patients were homozygotes, and 47 were heterozygotes. Both non-Jewish homozygotes and heterozygotes had lower factor XI activity than respective Jewish subjects. Twenty-eight homozygotes whose factor XI clotting activities (XI:C) were 1.5% to 13% had factor XI-related antigen (XI:RAG) levels less than 10% by EIA. In 72 homozygotes, including 22 patients who were also tested with EIA, XI:C was 2.9% +/- 3.0% (mean +/- SD) and XI:RAG tested by RIA, 2.9% +/- 3.0%. In 47 heterozygotes, XI:C and XI:RAG tested by RIA were 51.9% +/- 16.6% and 51.0% +/- 16.2%, respectively. Similar results were obtained when only unrelated patients (62 homozygotes and 27 heterozygotes) were analyzed. There was a highly significant correlation between XI:C and XI:RAG (RIA) in 38 homozygotes and 47 heterozygotes (r = 0.94, n = 85, P less than 0.001). Thus, we failed to identify functionally abnormal factor XI molecules (CRM+ variant) in these patients with hereditary factor XI deficiency.

Black People↗
PubMed1980

Prevalence and inheritance of factor XI (plasma thromboplastin antecedent) deficiency in cattle.

A survey of 169 Holstein-Friesian cattle showed 21 heterozygous for Factor XI activity having activities of .43 +/- .10 units per milliliter compared with the normal .99 +/- .32 units per milliliter. The frequency of the mutant gene was .06; the 95% confidence limits for the frequency of homozygotes in the population were .1 to .8%, and for heterozygotes the frequency was 7.0 to 16.0%. Test matings indicated this disorder is transmitted as an autosomal recessive gene.

Animals↗
PubMed1989

Factor XI (plasma thromboplastin antecedent) deficiency in Ashkenazi Jews is a bleeding disorder that can result from three types of point mutations.

Factor XI (plasma thromboplastin antecedent) deficiency is a blood coagulation abnormality occurring in high frequency in Ashkenazi Jews. Three independent point mutations that result in a blood coagulation abnormality have been identified in the factor XI gene of six unrelated Ashkenazi patients. These mutations either disrupt normal mRNA splicing (type I), cause premature polypeptide termination (type II), or result in a specific amino acid substitution (type III). The three different genotypes were present in the six patients as type I/II, type II/III, and type III/III. Thus far no correlation was found between the three genotypes and the bleeding tendency in these patients.

Adult↗
PubMed1993

Combined hereditary factor XI (plasma thromboplastin antecedent) deficiency, von Willebrand's disease, and xeroderma pigmentosum in a Japanese family.

We report a 28-year-old-Japanese male who had a skin tumor derived from variant type xeroderma pigmentosum (XP), combined with factor XI (FXI) deficiency and type IIB von Willebrand's disease (vWd). The patient had abnormal bleeding history on tooth extraction. FXI clotting activity (FXI:C) and antigen (FXI:Ag) were remarkably decreased (< 0.01 U/ml, < 0.02 U/ml, respectively). Factor VIII (FVIII) clotting activity, von Willebrand factor antigen (vWf:Ag), and ristocetin cofactor (RCoF) were 0.43 U/ml, 45%, and 57%, respectively. Ristocetin-induced platelet agglutination (RIPA) revealed hyper-aggregation compared with a normal control. Multimeric composition of vWf in plasma showed a reduction in high molecular weight forms. The family study revealed two other subjects with homozygous hereditary FXI deficiency and vWd, and five subjects with heterozygous FXI deficiency. The relationship between FXI deficiency and vWd is discussed and previously reported cases are reviewed.

Adult↗