Gynaecological and obstetrical bleeding in Caucasian women with congenital factor XI deficiency: Results from a twenty-year, retrospective, observational study.

INTRODUCTION: Factor XI (FXI) deficiency is a mild bleeding disorder, common among Ashkenazis, that may be underestimated in Caucasians. Management of FXI deficiency in women is a challenge, due to its unpredictable bleeding tendency and the little evidence available on this issue. OBJECTIVE: To describe gynaecological/obstetrical bleeding complications and to analyze the effectiveness and safety of the antihaemorrhagic treatment among women with FXI deficiency. MATERIAL AND METHODS: A retrospective, observational study of 214 Caucasian subjects with FXI deficiency collected during 20 years (1994-2014) without clinical selection. RESULTS: We identified 95 women with FXI deficiency. Any haemorrhagic event was communicated by 26/95 (27.4%), being abnormal uterine bleeding the most frequently found (12/95, 12.6%). Nine postpartum haemorrhages were recorded from 136 deliveries (6.6%) in 57 women. Four postsurgical bleeding complications were registered among 25 gynaecological surgeries (16%) in 20 women. Abnormal uterine bleeding, postpartum and postsurgical haemorrhages were related to both a positive bleeding history and FXI:C values ≤43.5%. Prophylaxis with fresh frozen plasma, used in 12/25 (48%) gynaecological surgeries, did not prevent from postoperative bleeding in three cases, but two developed severe adverse reactions. CONCLUSION: Women with FXI deficiency, especially those with a positive history of bleeding or FXI:C ≤43.5%, are at risk of developing gynaecological/obstetrical haemorrhages, most of them mild/moderate. Systematic prophylaxis has questionable effectiveness, but might cause severe side effects.

Review: Factor XI deficiency: review and management in pregnant women.

Factor XI deficiency is a rare disease found predominantly in Ashkenazi Jews. There is a poor correlation between factor XI level and bleeding in patients with factor XI deficiency. Individuals with severe factor XI deficiency are usually at risk of excessive bleeding after surgery and injury, particularly when trauma involves tissues rich in fibrinolytic activity. Women with partial or severe deficiency are at risk of excessive uterine bleeding during labor. The unpredictable nature of factor XI deficiency complicates management during pregnancy and delivery. This review gives an overview of the management of pregnant women with factor XI deficiency.

Factor XI deficiency--resolving the enigma?

The management of factor XI deficiency is not straightforward for three reasons: firstly, the role of this factor in the coagulation pathway is not clearly understood; secondly, the bleeding tendency, although mild, is unpredictable and does not clearly relate to the factor XI level; and thirdly, all treatment products, although available, have some potentially serious side effects. These factors (or enigmas) contribute to the variable management of patients with this coagulation factor deficiency, but recent research is helping to clarify some of these areas.

Molecular genetic analysis of severe coagulation factor XI deficiency in six Italian patients.

BACKGROUND AND OBJECTIVES: Factor XI (FXI) deficiency is a rare autosomal recessive coagulopathy which is, however, frequent among Ashkenazi Jews. Two mutations, type II (Glu117stop) and type III (Phe283Leu), account for the majority of abnormal alleles in this population. The aim of this study was to analyze the molecular basis of FXI deficiency in six unrelated Italian probands with severe deficiency, a population hitherto largely unexplored. DESIGN AND METHODS: All patients showed unmeasurable functional FXI levels in plasma. Mutational screening was performed by sequencing. Haplotype analysis was performed using intragenic polymorphisms. Expression studies were performed by transient transfection in COS-1 cells. RESULTS: Sequencing identified two novel mutations: a nonsense mutation (Cys118stop) in exon 5 in two probands, and a 6-bp deletion (643-648delATCGAC) in exon 7 in one proband. The Cys118stop is predicted to cause FXI deficiency by a secretion defect and/or by increased mRNA degradation. The 6-bp deletion causes the loss of residues Ile197 and Asp198. There was a remarkable secretion impairment of the deleted FXI protein. In four of the six probands, the type II mutation was found. Haplotype analysis in patients carrying the type II mutation revealed that they share a common haplotype, perhaps derived from a Jewish ancestor. INTERPRETATION AND CONCLUSIONS: The identification and characterization of two novel mutations widen the mutational spectrum of FXI deficiency. Haplotype analysis is compatible with a Jewish origin of the type II mutation. The high occurrence of the type II mutation among Italian patients will be helpful to direct future genetic screenings.

A common ancestral mutation (C128X) occurring in 11 non-Jewish families from the UK with factor XI deficiency.

Factor XI (FXI) deficiency is a mild bleeding disorder that is particularly common in Ashkenazi Jews, but has been reported in all populations. In Jews, two FXI gene (F11) mutations (a stop codon in exon 5, E117X, type II, and a point mutation in exon 9, F283L, type III) are particularly common, but in other populations a variety of different mutations have been described. In the Basque region of France one mutation, C38R in exon 3, was found in eight of 12 families studied, haplotype analysis suggesting a founder effect. In the course of screening 78 unrelated individuals (including 15 Jewish and 12 Asian) we have found 10 Caucasian non-Jewish patients with the mutation C128X in exon 5. Individuals were investigated because of a personal or family history of bleeding, or finding a prolonged activated partial thromboplastin time. Individuals negative for the type II and type III mutations were screened by a combination of SSCP and heteroduplex analysis. The C128X mutation was found in 10 families (one previously described). Among three individuals with severe FXI deficiency, one was homozygous for the C128X mutation, and two were compound heterozygotes for the C128X and another mutation; other individuals were carriers of the C128X mutation. This is a nonsense mutation producing a truncated protein; individuals have FXI antigen levels concordant with FXI coagulant activity. Haplotype analysis of 11 families, including a further kindred previously reported from the USA, but which originally came from the UK (in which the index patient was homozygous for C128X), suggests a founder effect.

Factor XI deficiency in the French Basque Country.

Thirty-nine patients with factor XI deficiency were diagnosed in our general hospital, which serves all the French Basque Country (about 290 000 inhabitants), between 1985 and 1995. Biological and clinical data of these cases are reported herein. Factor XI deficiency seems significantly more frequent in Basques than in the other non-Ashkenazi populations. Molecular studies should be performed for typing these cases in the view of population genetics.

Identification of mutations and polymorphisms in the factor XI genes of an African American family by dideoxyfingerprinting.

Congenital deficiency of factor XI is a rare condition associated with a mild to moderate bleeding diathesis that is most commonly found in persons of Jewish ancestry. The disorder has been reported sporadically in a number of other ethnic groups, but rarely in the black population. We report on the genetic analysis of the factor XI genes of two African American patients: a 9-year-old boy (the propositus) with mild factor XI deficiency and his mother. Both individuals have lifelong histories of excessive bleeding. Dideoxyfingerprinting, a technique combining components of single-strand conformational polymorphism analysis and dideoxy-chain termination sequencing, was used in the analysis. Both patients were found to be heterozygous for a mutation changing serine 248 to asparagine [corrected], whereas the propositus was heterozygous for an additional mutation on the paternal allele changing glutamine 226 to arginine. Both mutations reside in the third apple domain of the factor XI heavy chain, an area that has been shown to contain binding sites for factor IX, platelets, and glycosaminoglycans. Previously reported mutations in the factor XI gene seem to cause deficiency primarily by reducing protein expression. Because both alleles in the propositus contain amino acid substitutions, the significant amount of circulating factor XI in his plasma must be comprised entirely of abnormal molecules. Factor XI circulates as a homodimer, and the presence of mutations in both alleles of the factor XI gene suggests that his bleeding disorder is caused in part by the effect of the two abnormal gene products forming dimers in different combinations. Three neutral (not associated with amino acid changes) DNA polymorphisms were also identified in the two subjects: a C to T change at nucleotide 472 in exon 5, A to G at nucleotide 844 in exon 8, and T to C at nucleotide 1234 in exon 11. Analysis of a random sample of normal volunteers showed that these polymorphisms are relatively common, with allele frequencies of 7.4%, 19%, and 18%, respectively. This suggests that there is considerable genetic heterogeneity in the factor XI gene.

The two common mutations causing factor XI deficiency in Jews stem from distinct founders: one of ancient Middle Eastern origin and another of more recent European origin.

Previous studies showed that factor XI (FXI) deficiency commonly observed in Ashkenazi Jews is caused by two similarly frequent mutations, type II (Glu117stop) and type III (Phe283Leu) with allele frequencies of 0.0217 and 0.0254, respectively. In Iraqi Jews, who represent the ancient gene pool of Jews, only the type II mutation was observed with an allele frequency of 0.0167. In this study we sought founder effects for each mutation by examination of four FXI gene polymorphisms enabling haplotype analysis in affected Jewish patients of Ashkenazi, Iraqi, and other origins and in Arab patients. Initial population surveys of 387 Middle Eastern Jews (excluding Iraqi Jews), 560 North African/Sephardic Jews, and 382 Arabs revealed allele frequencies for the type II mutation of 0.0026, 0.0027, and 0.0065, respectively. In contrast, the type III mutation was not detected in any of these populations. All 60 independent chromosomes bearing the type III mutation were solely observed in Ashkenazi Jewish patients and were characterized by a relatively rare haplotype. All 103 independent chromosomes bearing the type II mutation in patients of Ashkenazi, Iraqi, Yemenite, Syrian, and Moroccan Jewish origin and of Arab origin were characterized by another distinct haplotype that was rare among normal Ashkenazi Jewish, Iraqi Jewish, and Arab chromosomes. These findings constitute the first example of a mutation common to Ashkenazi Jews, non-Ashkenazi Jews, and Arabs and are consistent with the origin of type II mutation in a founder before the divergence of the major segments of Jews. Our findings also indicate that the type III mutation arose more recently in an Ashkenazi Jewish individual.

Factor XI deficiency.

That factor XI has a role in normal blood coagulation is evidenced by the fact that patients with deficiency are prone to excessive bleeding after haemostatic challenge. The role of factor XI in physiological processes has become clearer since the discovery that it is activated by thrombin; this fact has contributed to a revised model of blood coagulation. Factor XI deficiency is particularly common in Ashkenazi Jews. Bleeding is typically provoked by surgery in areas of increased fibrinolysis, and is not restricted to individuals with severe deficiency. The bleeding tendency is variable and the reasons for this are not fully understood, although in severe deficiency there is some correlation between phenotype and genotype. The factor XI gene is 23 kb long, and two mutations are responsible for most factor XI deficiency in the Ashkenazi population. A total of 13 mutations have thus far been published. Factor XI deficient patients may need specific therapy to cover surgery and dental extractions. Although a factor XI concentrate is available there have been recent reports of coagulation activation and thrombosis indicating that it should be used cautiously. Fresh frozen plasma may be an acceptable alternative in some situations.

Molecular genetics aspects of factor XI deficiency and Glanzmann thrombasthenia.

Factor XI deficiency and Glanzmann thrombasthenia are among the hereditary disorders frequently encountered in Israel. Factor XI deficiency is particularly frequent in Ashkenazi (European) Jews with 1:190 individuals affected by the severe deficiency and 8.1% of the population being heterozygotes. So far 4 mutations causing factor XI deficiency have been identified of which the type II (a non-sense mutation) and type III (a missense mutation) are predominant and type I and IV observed only in 5 families. Recently, the type II mutation was observed in Iraqui-Jews as well with 3.7% of 400 unrelated subjects being heterozygotes and with the type III mutation completely absent. Since Iraqui-Jews represent the original gene pool of Jews who lived in Babylon 2500 years ago we hypothesize that the type II mutation is ancient and that the type III mutation occurred more recently, after the divergence of the original Babylonian Jews into Ashkenazi, Sephardic (Spanish) and Middle Eastern Jews. Preliminary data on factor XI intragenic polymorphic markers indeed indicate that type II and type III mutations reside on chromosomes each characterized by a different specific haplotype. Fifty living patients with type I Glanzmann thrombasthenia (28 families) have been observed in Israel. Most of them are Iraqui-Jewish and the rest are Arabs (5 families) and one Iranian Jewish. All Iraqui-Jewish patients have an IIbp deletion within exon 12 of the glycoprotein (GP) IIIa resulting in a shift of the reading frame that leads to premature termination of the GPIIIa synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Factor XI: a review of its biochemistry and deficiency.

The biochemistry and physiology of Factor XI have been reviewed. The clinical history of our 25 patients was reviewed and compared with others' experiences. Factor XI deficiency remains enigmatic in that there is no correlation between Factor XI levels and clinical manifestations. Approximately 40 to 50% of all persons lacking Factor XI are of Ashkenazi Jewish extraction, and the remainder are represented by nearly all populations. Persons may be found to lack Factor XI because of evaluation for hemorrhage, evaluation of a prolonged PTT, or through family or other genetic studies. Hemorrhage is not as severe as in patients with hemophilia A or B. Data are presented suggesting that hemorrhage may, in part, be associated with aspirin use.

The factor of factor XI deficiency in thyroid neoplasia.

Forty-three patients with factor XI deficiency detected by prolonged partial thromboplastin times were reviewed over an 11-year period. They were predominantly Ashkenazim--18 men and 25 women--ranging in age from 20 to 92 years. Thirteen patients had a history of bleeding, and eight had a family history of factor XI deficiency. Six patients with thyroid disease with four significant tumors were found for a 9% incidence of associated neoplasia. These consisted of two adenomas and two papillary-mixed cancers in two men distinguished by an aggressive course by virtue of extensive nodal disease, local recurrence, and systemic metastases in whom factor XI was profoundly decreased. It would appear that there is an undue association of factor XI deficiency and thyroid neoplasia suggestive of a shared genetic disturbance. These cases illustrate the benefit of routine preoperative coagulopathy screening by use of prothrombin time, partial thromboplastin time, and platelet counts. Factor XI deficiency is an infrequent cause of excessive bleeding, and the operative morbidity of surgical management of affected individuals can be avoided by the use of fresh-frozen plasma before and after surgery.