Successful pregnancy in a woman with congenital factor XIII deficiency treated with substitutive therapy. Report of a second case

Successful perinatal management of a woman with congenital factor XIII deficiency using recombinant factor XIII: A case report and literature review

Factor XIII deficiency is an extremely rare autosomal recessive genetic disorder, occurring in 1 of 3-5 million people, and is associated with perinatal complications, such as habitual abortion and prolonged bleeding. Although plasma-derived factor XIII (Fibrogamin®) carries a risk of infection and contains very low concentrated forms of factor XIII (FXIII) used for a pregnant woman with congenital coagulation factor XIII deficiency, recombinant factor XIII (rFXIII, Novo Thirteen®; Tretten®, Novo Nordisk, Bagsvaerd, Denmark), which has no risk of infection and is highly concentrated, has emerged as a novel formulation. Herein, we report the first case of a Japanese pregnant woman with congenital coagulation factor XIII deficiency successfully managed by rFXIII. She had a good perinatal course without pregnancy-related complications and transfusion through the perinatal period.

Treatment with Recombinant Factor XIII (Tretten) in a Pregnant Woman with Factor XIII Deficiency

Patient: Female, 37

Final Diagnosis: Factor XIII deficiency

Symptoms: Bleeding • miscarriage

Medication: —

Clinical Procedure: —

Specialty: Hematology

Congenital factor XIII deficiency in women: a systematic review of literature

Factor XIII (FXIII) deficiency is a rare congenital bleeding disorder. There is a paucity of data in the literature about obstetrics and gynaecological problems in women affected by FXIII deficiency. The aim of this study was to examine gynaecological problems and obstetric complications and outcome in women with congenital FXIII deficiency. An electronic search was performed to identify the published literature on PUBMED, MEDLINE, EMBASE, Journals @OVID and CINAHL Plus databases using the following keywords: 'congenital factor XIII deficiency' AND 'women OR Pregnancy'. A total of 39 relevant articles were found and included in this systematic review; 27 case reports and 12 case series dating from 1964 to 2012. A total of 121 women were identified. Menorrhagia (26%) was the second most common bleeding reported after umbilical bleeding. Ovulation bleeding reported in 8% of women. Among 63 women, 192 pregnancies were reported; of these, 127 (66%) resulted in a miscarriage and 65 (34%) reached viability stage. In 136 pregnancies without prophylactic therapy, 124 (91%) resulted in a miscarriage and 12(9%) progressed to viability stage. Antepartum haemorrhage occurred in 5/65 (8%) pregnancies reaching viability stage while postpartum haemorrhage (PPH) seen in 16 (25%) cases. Women with congenital FXIII deficiency suffer significant bleeding complications. Menorrhagia and ovulation bleeding are common gynaecological problems and more prevalent than reported. Pregnancies in women with FXIII deficiency have a significant risk of miscarriage, placental abruption and PPH if not on prophylaxis treatment.

Factor XIII: a coagulation factor with multiple plasmatic and cellular functions

Factor XIII (FXIII) is unique among clotting factors for a number of reasons: 1) it is a protransglutaminase, which becomes activated in the last stage of coagulation; 2) it works on an insoluble substrate; 3) its potentially active subunit is also present in the cytoplasm of platelets, monocytes, monocyte-derived macrophages, dendritic cells, chondrocytes, osteoblasts, and osteocytes; and 4) in addition to its contribution to hemostasis, it has multiple extra- and intracellular functions. This review gives a general overview on the structure and activation of FXIII as well as on the biochemical function and downregulation of activated FXIII with emphasis on new developments in the last decade. New aspects of the traditional functions of FXIII, stabilization of fibrin clot, and protection of fibrin against fibrinolysis are summarized. The role of FXIII in maintaining pregnancy, its contribution to the wound healing process, and its proangiogenic function are reviewed in details. Special attention is given to new, less explored, but promising fields of FXIII research that include inhibition of vascular permeability, cardioprotection, and its role in cartilage and bone development. FXIII is also considered as an intracellular enzyme; a separate section is devoted to its intracellular activation, intracellular action, and involvement in platelet, monocyte/macrophage, and dendritic cell functions.

Gynecological and obstetrical manifestations of inherited bleeding disorders in women

Patients affected by bleeding disorders present a wide spectrum of clinical symptoms that vary from a mild or moderate bleeding tendency to significant episodes. Women with inherited bleeding disorders are particularly disadvantaged since, in addition to suffering from general bleeding symptoms, they are also at risk of bleeding complications from regular haemostatic challenges during menstruation, pregnancy and childbirth. Moreover, such disorders pose important problems for affected women due to their reduced quality of life caused by limitations in activities and work, and alteration of their reproductive life. These latter problems include excessive menstrual bleeding or menorrhagia, miscarriage, bleeding complications during pregnancy and after delivery and their related complications such as acute or chronic anaemia. The management of these women is difficult because of considerable inter-individual variation. Moreover, reliable information on clinical management is scarce, only a few available long term prospective studies of large cohorts provide evidence-based guideline about diagnosis and treatment.

Women and bleeding disorders

SUMMARY

While women are rarely affected by haemophilia, they are equally as likely as men to have other bleeding disorders. Menorrhagia, or heavy menstrual bleeding, is the most common symptom that they experience. Not only is menorrhagia more prevalent among women with bleeding disorders, but bleeding disorders are more prevalent among women with menorrhagia. Although menorrhagia is the most common reproductive tract manifestation of a bleeding disorder, it is not the only manifestation. Women with bleeding disorders appear to be at an increased risk of developing haemorrhagic ovarian cysts and possibly endometriosis. Women suspected of having a bleeding disorder or being a carrier of haemophilia should be offered diagnostic testing before getting pregnant to allow for appropriate preconception counselling and pregnancy management. During pregnancy, women with bleeding disorders may be at an increased risk of bleeding complications. At the time of childbirth, women with bleeding disorders appear to be more likely to experience postpartum haemorrhage, particularly delayed or secondary postpartum haemorrhage. As women with bleeding disorders grow older, they may be more likely to manifest gynaecological conditions which present with bleeding. Women with bleeding disorders are more likely to undergo a hysterectomy and are more likely to have the operation at a younger age. While women with bleeding disorders are at risk for the same obstetrical and gynaecological problems that affect all women, women with bleeding disorders are disproportionately affected by conditions that manifest with bleeding. Optimal management involves the combined expertise of haemostasis experts and obstetrician-gynaecologists.

Obstetric management of adolescents with bleeding disorders

Adolescents with bleeding disorders who become pregnant must contend with the dual challenges of their bleeding disorder and their pregnancy. Adolescents are more likely to terminate a pregnancy than adult women, and when they do carry a pregnancy, they are more likely to deliver prematurely. Otherwise, they are at risk for the same complications that adult women with bleeding disorders experience, particularly bleeding complications postpartum. Since one half to two thirds of adolescent pregnancies are unplanned, issues related to reproduction should be addressed during routine visits with the pediatrician, hematologist or gynecologist. Girls who are at risk of being carriers for hemophilia A and B, severe von Willebrand disease, and other severe bleeding disorders should have their bleeding disorder status determined before they become pregnant. During pregnancy, a plan should be established to ensure that both mother and fetus deliver safely. Young women at risk for severe bleeding or at risk of having a severely affected infant should be referred for prenatal care and delivery to a center where, in addition to specialists in high-risk obstetrics, there is a hemophilia treatment center or a hematologist with expertise in hemostasis. Prior to delivery or any invasive procedures, young women at risk for severe bleeding should receive prophylaxis. Since administration of desmopressin may result in hyponatremia, whenever available, virally inactivated or recombinant clotting factor concentrates should be used for replacement as opposed to fresh frozen plasma or cryoprecipitate.

Prophylaxis of bleeding episodes and surgical interventions in patients with rare inherited coagulation disorders

Rare inherited coagulation disorders (RICD) represent a group of inherited deficiencies of clotting factors characterized by a low prevalence in the general population (usually around 1:1,000,000 inhabitants) and, in severe cases (homozygous or compound heterozygotes), by the invariable occurrence of bleeding after invasive procedures if not adequately treated. Furthermore, spontaneous or post-traumatic severe bleeding may occur, as usually observed in patients with haemophilia, although less frequently. The clinical picture of patients with RICD may, however, be complicated by particular situations not encountered in haemophiliacs, such as gynaecological bleeding. The availability of virally-inactivated plasma-derived concentrates of the missing factors, apart from factor V, has rendered surgery and prophylaxis more feasible in these disorders, thus reducing the risk of life-threatening episodes and significantly improving the quality of life of affected patients. The goal for the future is to render this treatment accessible to all patients with these disorders, also to those living in developing countries.

Congenital blood coagulation factor XIII deficiency and successful deliveries: a review of the literature

Congenital deficiency of blood coagulation factor XIII is an uncommon, inherited disorder characterized by hemorrhagic diathesis, habitual abortions and defective wound healing. We analyzed 8 reported successful pregnancies in women with a congenital deficiency of A-subunit of factor XIII (XIIIA), in which the plasma level of maternal factor XIIIA and/or the precise replacement therapies are described. Because decidual bleeding usually begins from 5 to 6 weeks' gestation and, without replacement therapy, spontaneous abortion always occurs, we herein offer the following prenatal and peripartum management guidelines and observations: i) the level of plasma A-subunit of factor XIII antigen (XIIIA-Ag) or factor XIII activity (XIII-act) must be at least 2%-3%, and, if possible, higher than 10% to prevent decidual bleeding and miscarriage during the pregnancy; ii) factor XIIIA concentrate is better than fresh frozen plasma or cryoprecipitate for replacement therapy; iii) the administration of 250 international units (IU) every 7 days is sufficient to maintain the level of plasma XIIIA-Ag or XIII-act more than 10% in the early period of gestation (through 22 weeks' gestation); however, 500 IU every 7 days is indicated in the later period (from 23 weeks' gestation) to maintain that level; iv) during labor, the desired level of plasma XIIIA-Ag or XIII-act should be higher than 20%, and, if possible, higher than 30% in order to make ready for any risk of severe obstetrical hemorrhagic complications; thus a booster dose of 1000 IU is indicated before labor; v) no replacement therapy is necessary in the puerperium because it is usually uneventful without it.

The obstetric and gynaecological management of women with inherited bleeding disorders - review with guidelines produced by a taskforce of UK Haemophilia Centre Doctors' Organization

The gynaecological and obstetric management of women with inherited coagulation disorders requires close collaboration between obstetrician/gynaecologists and haematologists. Ideally these women should be managed in a joint disciplinary clinic where expertise and facilities are available to provide comprehensive assessment of the bleeding disorder and a combined plan of management. The haematologist should arrange and interpret laboratory tests and make provision for appropriate replacement therapy. These guidelines have been provided for healthcare professionals for information and guidance and it is also intended that they are readily available for women with bleeding disorders.

More than menorrhagia: a review of the obstetric and gynaecological manifestations of bleeding disorders

In women, menorrhagia may be the most common manifestation of a bleeding disorder, but it is not the only reproductive tract abnormality that women with bleeding disorders experience. Women with bleeding disorders appear to be at an increased risk of developing haemorrhagic ovarian cysts and possibly endometriosis. As they grow older, they may be more likely to manifest conditions, which present with bleeding such as fibroids, endometrial hyperplasia and polyps. Women with bleeding disorders are more likely to undergo a hysterectomy and are more likely to have the operation at a younger age. During pregnancy, they may be at greater risk of miscarriage and bleeding complications. At the time of childbirth, women with bleeding disorders appear to be more likely to experience postpartum haemorrhage, particularly delayed or secondary postpartum haemorrhage. Vaginal or vulvar haematomas, extremely rare in women without bleeding disorders, are not uncommon. While women with bleeding disorders are at risk for the same obstetrical and gynaecological problems that affect all women, they appear to be disproportionately affected by conditions that manifest with bleeding.

Recessively inherited coagulation disorders

Deficiencies of coagulation factors other than factor VIII and factor IX that cause bleeding disorders are inherited as autosomal recessive traits and are rare, with prevalences in the general population varying between 1 in 500 000 and 1 in 2 million for the homozygous forms. As a consequence of the rarity of these deficiencies, the type and severity of bleeding symptoms, the underlying molecular defects, and the actual management of bleeding episodes are not as well established as for hemophilia A and B. We investigated more than 1000 patients with recessively inherited coagulation disorders from Italy and Iran, a country with a high rate of recessive diseases due to the custom of consanguineous marriages. Based upon this experience, this article reviews the genetic basis, prevalent clinical manifestations, and management of these disorders. The steps and actions necessary to improve the condition of these often neglected patients are outlined.

Factor XIII A subunit-deficient mice developed severe uterine bleeding events and subsequent spontaneous miscarriages

To understand the molecular pathology of factor XIII (FXIII) deficiency in vivo, its A subunit (FXIIIA)-knockout (KO) mice were functionally analyzed. Although homozygous FXIIIA female KO mice were capable of becoming pregnant, most of them died due to excessive vaginal bleeding during gestation. Abdominal incisions revealed that the uteri of the dead mice were filled with blood and that some embryos were much smaller than others within a single uterus. A series of histologic examinations of the pregnant animals suggested that massive placental hemorrhage and subsequent necrosis developed in the uteri of the FXIIIA KO mice on day 10 of gestation. This was true regardless of the genotypes of fetuses. These results are reminiscent of spontaneous miscarriage in pregnant humans with FXIII deficiency and indicate that maternal FXIII plays a critical role in uterine hemostasis and maintenance of the placenta during gestation.

Polymorphisms in coagulation factor genes and their impact on arterial and venous thrombosis

Arterial and venous thromboses, with their clinical manifestations such as stroke, myocardial infarction (MI), or pulmonary embolism, are the major causes of death in developed countries. Several studies in twins and siblings have shown that genetic factors contribute significantly to the development of these diseases. Since the advent of molecular genetics in medicine, it has been a focus of interest to elucidate the role of mutations in various candidate genes and their impact on hemostatic disorders such as arterial and venous thromboses. In this article, we review the current knowledge of the contribution of polymorphisms in coagulation factors to the development of thrombotic diseases. We show that in arterial thrombosis, results are controversial. Only for factor XIII 34Leu a protective effect on the development of myocardial infarction has been demonstrated in several studies. No other single polymorphism in a coagulation factor could be confirmed as a relevant risk factor, although there is evidence for a role of factor V Arg506Gln, factor VII Arg353Gln, and vWF Thr789Ala polymorphisms in patient subgroups. Further studies will be necessary to confirm the value of testing for genetic polymorphisms in arterial thrombosis. A large body of data is available on the role of factor V Arg506Gln and the prothrombin G20210A mutation in venous thrombosis. Some papers already recommend diagnosis and treatment strategies. We will discuss these recent publications on venous thrombosis in our review.

Delayed umbilical bleeding--a presenting feature for factor XIII deficiency: clinical features, genetics, and management

OBJECTIVES

The objectives of this study were 1) to assess the importance of an early diagnosis for factor XIII (FXIII) deficiency, and 2) to investigate the molecular basis and mechanism(s) of disease in the patients under study.

METHODS

The case histories of 6 FXIII-deficient patients were examined to assess the influence of early versus delayed diagnosis and replacement therapy. The nucleotide sequence of the FXIIIA gene was determined to identify the underlying mutations responsible for the bleeding diathesis in each patient. Molecular modeling was used to predict the mechanism(s) of disease causation for each mutation.

RESULTS

All cases presented with umbilical hemorrhage. Patients 1 to 3 were diagnosed, and their prophylactic therapy was commenced in infancy. Diagnosis in patients 4 to 6 was considerably delayed and, as a result, they continued to suffer from many bleeding symptoms. The FXIIIA gene mutations identified in these patients were as follows: a homozygous GAA-->AAA mutation in codon 102 (Glu102Lys) in patient 1 and a homozygous AGC-->AGG mutation in codon 295 (Ser295Arg) in patients 2 to 6. These mutations segregate with disease and are absent from the normal population, suggesting that they are likely to be disease-causing sequence changes. Computer modeling indicates that both the Lys102 and Arg295 mutants are unable to fold correctly, and probably result in unstable FXIIIA molecules.

CONCLUSIONS

We demonstrate the importance of recognizing delayed umbilical hemorrhage as a presenting feature for congenital FXIII deficiency, and the value of early diagnosis and prophylaxis. The bleeding disorder of patient 1 was attributable to a homozygous Glu102Lys mutation in FXIIIA. A homozygous Ser295Arg mutation in FXIIIA was responsible for FXIII deficiency in patients 2 to 6.

Factor XII but not protein C, protein S, antithrombin III, or factor XIII is a predictor of recurrent miscarriage

OBJECTIVE

To investigate whether a decrease in the values of protein C (PC), protein S (PS), antithrombin III (ATIII), factor XII (FXII), or factor XIII (FXIII) has predictive value for subsequent miscarriages.

DESIGN

Prospective study.

SETTING

Nagoya City University Medical School.

PATIENT(S)

A total of 536 patients with a history of two or more first-trimester miscarriages.

INTERVENTION(S)

One hundred and twelve patients treated with low-dose aspirin were excluded from the analysis.

MAIN OUTCOME MEASURE(S)

The subsequent pregnancy outcome of 424 patients was compared for abnormal and normal levels of each parameter.

RESULT(S)

There were no differences in the subsequent miscarriage rates between abnormal and normal values of PC, PS, ATIII, and FXIII. However, the rate with abnormal FXII is significantly higher than that with normal FXII.

CONCLUSION(S)

A decrease in FXII (but not in PC, PS, ATIII, or FXIII) predicts subsequent miscarriage in patients with a history of first-trimester recurrent miscarriages.

Current therapy for rare factor deficiencies

Haemophilia A and B and von Willebrand disease account for 80-85% of all inherited bleeding disorders. The other 15% are represented by deficiencies of fibrinogen, prothrombin, or factors V, VII, X, XI, or XIII. In addition, acquired factor deficiencies are seen in a variety of conditions ranging from malignancies to autoimmune disorders. The spectrum of symptoms in these conditions varies from severe and life-threatening haemorrhage to a mild bleeding diathesis. The diagnosis depends on demonstration of decreased activity of one of the clotting factors. Due to the rarity of each of the individual factor deficiencies, purified factor concentrates are not as readily available as they are for haemophilia A and B. Treatment of rare clotting factor deficiencies consists of the most purified blood product available that contains the missing factor. Depending on which factor is deficient, either purified concentrates, prothrombin complex concentrates, cryoprecipitate, or fresh frozen plasma can be used. In addition, recombinant factor VIIa is available for treating factor VII deficient patients.

Maternal blood coagulation factor XIII is associated with the development of cytotrophoblastic shell

We analysed the early implantation tissues of normal women and of a patient with congenital factor XIII deficiency in order to study the role of maternal subunit A of factor XIII (XIIIA) in the development of extravillous cytotrophoblast. The patient had received adequate administration of factor XIIIA concentrate only up to 7 weeks of gestation (wG). Her pregnancy was maintained until the latter half of 8 wG, but was terminated by intrauterine fetal death at 9 wG. Immunohistochemical staining of cytokeratin, XIIIA and subunit S of factor XIII was performed in the early implantation tissues of normal women and of this patient. Numerous well-formed cytotrophoblastic shells and Nitabuch's layers were detected in implantation tissues at 7-8 wG in normal women, and XIIIA was present in the intercellular space in well-formed cytotrophoblastic shells, while the cytotrophoblastic shells and Nitabuch's layers in this patient's implantation tissue were poorly-formed. Furthermore, XIIIA was not detected around them. It is suggested that when the maternal plasma activity of factor XIII is low, the concentration of XIIIA at the placental bed is also low, leading to the insufficient formation of cytotrophoblastic shell and therefore an increased probability of miscarriage in patients with congenital factor XIII deficiency.

Bleeding risk and reproductive capacity among patients with factor XIII deficiency: a case presentation and review of the literature

Factor XIII deficiency is an uncommon, inherited bleeding disorder that usually manifests in infancy or early childhood, involving both boys and girls. We present the case of a woman who had experienced two previous intracranial bleeding events, and was treated before and during her current pregnancy with factor XIII concentrate. Her pregnancy was successful, and she experienced an uncomplicated vaginal delivery. To better understand the issues surrounding bleeding, reproductive capacity, and management of factor XIII deficiency during pregnancy, we conducted a systematic literature review using MEDLINE from 1966 to December 1998. We also examined the bibliographic references from all articles, and included all cases, case reports, or case series of patients with factor XIII deficiency. We retrieved data on 117 patients from 37 articles, the majority of which had type II deficiency. Among untreated patients with type II factor XIII deficiency, the literature suggests an elevated mortality rate due to uncontrolled bleeding and intracranial hemorrhage. Because of its high degree of efficacy, the evidence supports the use of life long prophylactic therapy with at least monthly infusions of factor XIII concentrate, including during pregnancy. The opinion that women with type II factor XIII deficiency have inevitable recurrent abortions, or that men are sterile, is not well substantiated. No data were found on whether treatment alters male reproductive capacity. A policy of universal factor XIII replacement, starting in childhood, will likely enable more patients to attain reproductive status. The development of an international data registry would optimally address both bleeding risk and reproductive capacity among patients with factor XIII deficiency.

Novel aspects of blood coagulation factor XIII. I. Structure, distribution, activation, and function

Blood coagulation factor XIII (FXIII) is a protransglutaminase that becomes activated by the concerted action of thrombin and Ca2+ in the final stage of the clotting cascade. In addition to plasma, FXIII also occurs in platelets, monocytes, and monocyte-derived macrophages. While the plasma factor is a heterotetramer consisting of paired A and B subunits (A2B2), its cellular counterpart lacks the B subunits and is a homodimer of potentially active A subunits (A2). The gene coding for the A and B subunits has been localized to chromosomes 6p24-25 and 1q31-32.1, respectively. The genomic as well as the primary protein structure of both subunits has been established, and most recently the three-dimensional structure of recombinant cellular FXIII has also been revealed. Monocytes/macrophages synthesize their own FXIII, and very likely FXIII in platelets is synthesized by the megakaryocytes. Cells of bone marrow origin seem to be the primary site for the synthesis of subunit A in plasma FXIII, but hepatocytes might also contribute. The B subunit of plasma FXIII is synthesized in the liver. Plasma FXIII circulates in association with its substrate precursor, fibrinogen. Fibrin(ogen) has an important regulatory role in the activation of plasma FXIII. The most important steps of the activation of plasma FXIII are the proteolytic removal of activation peptide by thrombin, the dissociation of subunits A and B, and the exposure of the originally buried active site on the free A subunits. The end result of this process is the formation of an active transglutaminase, which cross-links peptide chains through epsilon(gamma-glutamyl)lysyl isopeptide bonds. Cellular FXIII in platelets becomes activated through a nonproteolytic process. When intracytoplasmic Ca2+ is raised during platelet activation, the zymogen--in the absence of subunit B--assumes an active configuration. The protein substrates of activated FXIII include components of the clotting-fibrinolytic system, adhesive and contractile proteins. The main physiological function of plasma FXIII is to cross-link fibrin and protect it from the fibrinolytic plasmin. The latter effect is achieved mainly by covalently linking alpha 2 antiplasmin, the most potent physiological inhibitor of plasmin, to fibrin. Plasma FXIII seems to be involved in wound healing and tissue repair, and it is essential to maintaining pregnancy. Cellular FXIII, if exposed to the surface of the cells, might support or perhaps take over the hemostatic functions of plasma FXIII; however, its intracellular role has remained mostly unexplored.

Factor XIII: inherited and acquired deficiency

Factor XIII (XIII), an enzyme found in plasma (present as a pro-enzyme), platelets and monocytes, is essential for normal haemostasis. It may also have a role to play in the processes of wound healing and tissue repair. Inherited XIII deficiency results in a life-long, severe bleeding diathesis which, if untreated, carries a very high risk of death in early life from intracranial bleeding. XIII is a zymogen requiring thrombin and calcium for activation. In plasma, XIII has two subunits: the 'a' subunit, which is the active enzyme, and the 'b' subunit which is a carrier protein. Activated XIII modifies the structure of clot by covalently crosslinking fibrin through an epsilon (gamma-glutamyl)lysine link. It also crosslinks other proteins, including fibronectin and alpha-2-plasmin inhibitor (alpha-2PI), into the clot through the same link. Clot modified by XIII is physically stronger, relatively more resistant to fibrinolysis and may be a more suitable medium for the ingrowth of fibroblasts. Inheritance of factor XIII is autosomal recessive. The majority of patients with the inherited defect show no XIII activity and absence of 'a' subunit protein in plasma, platelets and monocytes. At the molecular level, the defect is not a major gene rearrangement or deletion, but most likely a single point mutation which may be different in each family. Because of the severity of the bleeding diathesis, prophylaxis is desirable and has been shown to be very effective as the in vivo half-life of plasma XIII is long, and low plasma levels are sufficient for haemostasis. Acquired inhibitors have been reported in only two cases with inherited XIII deficiency. Acquired XIII deficiency has been described in a variety of diseases and bleeding has been controlled by therapy with large doses of XIII in such conditions as Henoch-Schönlein purpura, various forms of colitis, erosive gastritis and some forms of leukaemia. Large dose XIII therapy has also been used in an endeavour to promote wound healing after surgery and bone union in non-healing fractures. The use of XIII in these conditions remains controversial. Very rarely a bleeding diathesis results from the development of a specific inhibitor to XIII arising de novo, often as a complication in the course of a disease or in association with long-term drug therapy. The bleeding diathesis in these patients is difficult to treat.

Clinical pharmacokinetics of a placenta-derived factor XIII concentrate in type I and type II factor XIII deficiency

Limited data are available about the pharmacokinetics of placenta-derived factor XIII (FXIII) concentrate in patients with FXIII deficiency. This concentrate contains only the active subunit A but not the carrier subunit B of the factor, and perplexities have been raised about its clinical use. Moreover, no data are available on its use in the rare patients completely lacking both subunit A and subunit B. Therefore, we evaluated the pharmacokinetics of a commercial placenta concentrate in three patients with FXIII deficiency: two lacking subunit A (type II) and one lacking both subunits (type I). The elimination half-life of the infused placenta subunit A in the three patients was very similar (280, 283, and 272 hr) and was also consistent with the previously reported data for plasma-derived FXIII. No thrombin-independent activity was observed in our concentrate batches. The recovery was significantly lower in the type I patient, in whom infusion of subunit A was not able to elicit a monthly increment of subunit B, as usually observed in type II patients. Monthly infusions of placenta concentrate (at higher dosage in type I patient) have been administered to our patients for two to three years and no evidence of inhibitor against factor XIII activity has been observed. We conclude that placenta concentrates may be as effective as plasma derivatives in replacement therapy of factor XIII deficiency, even in patients who lack subunit B.

Fibrinolysis and factor XIII in women with spontaneous abortion

In the present study, parameters of the fibrinolytic system and factor XIII were determined in 26 women with spontaneous abortion and in 21 women with intact pregnancies to gain insight into the role of fibrinolysis in spontaneous abortion. Both groups of women did not significantly differ from each other in age or weeks of pregnancy. There were no differences in euglobulin lysis time (ELT), tissue plasminogen activator (t-PA) antigen, and plasminogen activator inhibitor type 1 (PAI-1) antigen between the study group and the control group. Factor XIII activity was significantly decreased in patients during abortion. In the present study, changes of fibrinolytic parameters measured in teh cubital vein blood of patients with abortion were not observed although local changes in fibrinolytic activity had been associated with spontaneous abortion. The pathophysiological role of the decrease in factor XIII activity observed in the present study remains to be elucidated.

Immunohistochemical detection of factor XIII subunit a in histiocytes of human uterus

As spontaneous abortion is a frequent finding in females with Factor XIII (FXIII) deficiency it has been presumed that this clotting factor is essential to normal pregnancy. FXIII subunit a (FXIII A) has been demonstrated in the homogenate of human uterus, but no information on its cellular distribution has been published, so far. In the present study first FXIII A was detected in paraformaldehyde-fixed, paraffin-embedded sections of human uterus by immunoperoxidase technique. Cells containing FXIII A were localized between collagen fibrils stained by Picrosirius Red F3B in the connective tissue. To characterize them the immunofluorescent detection of FXIII A was combined by the visualization of different marker antigens of monocytes and macrophages recognized by Leu-M3, RFD7, anti-HLA-DR and DAKO-anti-macrophage monoclonal antibodies on frozen sections. The coexpression of FXIII A with monocyte and macrophage differentiation marker antigens clearly proves that cells containing FXIII A in the uterus are monocyte-derived tissue macrophages. The results well agree with our previous findings demonstrating FXIII A in human monocytes and different types of macrophages. On the basis of these results, the presence of FXIII A does not seem to be a specificity of the uterus but a characteristic of monocyte/macrophage cell line including tissue macrophages, in general.