Hereditary coagulopathies in pregnancy

Management of Pregnancy in a Chilean Patient with Congenital Deficiency of Factor VII and Glanzmann's Thrombasthenia Variant

Patients with inherited bleeding disorders are rare in obstetric practice but present with prolonged bleeding even after minor invasive procedures. They require a combined approach with obstetric and hematological management of each case, including the neonatal management of a possibly affected fetus. We present the case of a pregnancy in a patient with combined Factor VII deficiency and Glanzmann's thrombasthenia, the successful obstetric and hematological management of the case, and a review of the literature.

Characterization of a Cys329Gly mutation causing hereditary factor VII deficiency

We have previously reported a homozygous Cys329Gly mutation in a Chinese patient with factor VII (FVII) deficiency. Others have found a heterozygous Cys329Gly mutation in the F7 gene from patients of three different pedigrees. However, none of the reports included the expression and characterization of the mutant FVII in vitro. To investigate the effect of Cys329Gly on FVII function, we carried out transient transfections of baby hamster kidney cells (BHK-21) with a mutant FVII construct and compared the results to those obtained using a wild-type FVII construct and vector control. The results demonstrate that the level of FVII:Ag secreted into the medium by transfected BHK-21 cells with mutant construct was not affected, but the coagulation activity of the mutant FVII was undetectable. We conclude that Cys329 is critical to FVII coagulation, and the replacement of cysteine 329 by glycine leads to the loss of coagulation activity in the patients, possibly the molecular basis for FVII deficiency in the patients.

Pregnancy and oral contraceptives in congenital bleeding disorders of the vitamin K-dependent coagulation factors

Pregnancies and deliveries represent important hemostatic challenges for congenital coagulation disorders. The same is true for the assumption of oral contraceptives. Available information mainly deals with von Willebrand's disease, factor XI (FXI) deficiency and carriers of hemophilia A. Data concerning patients with congenital prothrombin complex factor deficiencies are very scanty. In the present study, data of a total of 27 women are presented, 11 patients with homozygous or double heterozygous deficiencies of FII, FVII and FX, together with 16 cases of hemophilia B carriers. The patients with FII, FVII or FX defects had a total of 14 pregnancies and often needed transfusion therapy. Proper management resulted in a decrease in postpartum bleeding and satisfactory fetal outcome. Elective cesarean delivery seems indicated only in recent years. Carriers of hemophilia B had a total of 19 pregnancies but showed no bleeding and needed no substitutive therapy. Searching the literature, we discovered only 9 additional patients with prothrombin deficiency or FX deficiency, having a total of 16 pregnancies. On the contrary, there were at least 17 additional patients with FVII deficiency, with a total of 21 pregnancies. The management of the diseases has been variable, but in substantial agreement with the personal observations. Oral contraceptive therapy was administered in some of our patients and in a few additional cases described in the literature. Medication was always well tolerated and patients who took it for a long period of time showed a decrease in menometrorrhagia and an improvement in hematocrit levels. This led to a decrease in transfusional needs and to improved general conditions.

Pregnancy and oral contraceptives in factor V deficiency: a study of 22 patients (five homozygotes and 17 heterozygotes) and review of the literature

Information on the effect of pregnancy or oral contraceptives (OC) in congenital factor V (FV) deficiency is scanty. The personal investigation of five homozygous and 17 female heterozygous showed that patients with severe deficiency bleed considerably at the time of delivery. However, bleeding can be controlled properly by administration of fresh frozen plasma with excellent foetal outcome. The safe level for adequate haemostasis seems around 25% of normal. On the contrary, heterozygote patients show no significant postpartum bleeding and therefore need no substitution therapy. Oral contraceptives were taken and well tolerated by four of our homozygous patients and appear to be beneficial because they cause a decrease in menometrorrhagies thereby improving the anaemia and decreasing transfusional needs. One patient took hormonal replacement therapy with no undue effects. No thrombosis was noted in the propositae during oral contraceptive therapy. The review of the literature has allowed the gathering of information on 20 additional pregnancies. The foetal outcome was satisfactory in every instance. Excessive bleeding was noted in 11 pregnancies. In seven of the remaining pregnancies, no undue bleeding was noted thanks to appropriate substitution therapy. In the remaining two pregnancies no bleeding was noted and no substitution therapy was given. No data are apparently available in the literature about the use of OCs in FV deficiency.

[Factor X deficiency and pregnancy]

Factor X deficiency is one of the rarest inherited coagulation disorders. It is an autosomal recessive inherited disease. In its homozygous form factor X deficiency has an estimated prevalence of 1: 500,000. However in its heterozygous form it has an estimated frequency of 1: 500 to 1: 2000. Pregnancy in women with congenital factor X deficiency has been associated with adverse foetal outcomes. We report a case of pregnancy in a woman with factor X deficiency. She was treated early during labour with prophylactic replacement of prothrombin complex concentrates (Kaskadil). An initial infusion of 40 UI.kg-1 of factor X was followed by 20 UI.kg-1 every 24 hours during three days. During labour and peripartum maternal coagulation was screened. She delivered a healthy baby at 33 weeks of gestation. No episode of abnormal bleeding was observed. Therefore in this case, prophylactic therapy using prothrombin complex concentrates during labour and delivery did prevent severe haemorrhages.

Novel mutations in the Factor VII gene of Taiwanese Factor VII-deficient patients

The genetic defects of four Taiwanese patients with factor VII (FVII) deficiency were studied. FVII activity and antigen levels were < 1 u/dl and 125.7 u/dl (patient I), < 1 u/dl and < 1 u/dl (patient II), 3.4 u/dl and 5.9 u/dl (patient III), and 1.2 u/dl and 30.4 u/dl (patient IV) respectively. The 5' flanking region, and all exons and junctions were amplified using polymerase chain reaction and sequenced. Patient I was homozygous for a 10824C-->A transversion with Pro303-->Thr mutation in exon 8. In patient II, a heterozygous transversion, 9007+1G-->T at the IVS6, a heterozygous decanucleotide insertion polymorphism at -323 (both mutations present in his father) and a heterozygous deletion, del TC (26-27) in exon 1A (originating from his mother) were identified. Patient III had a homozygous 10961T-->G transversion with His348-->Gln mutation in exon 8. Patient IV had a heterozygous 10902T-->G transversion with Cys329-->Gly mutation in exon 8 (transmitted to her second son) and a heterozygous decanucleotide insertion polymorphism at -323 (transmitted to her third son). All but one of the FVII gene mutations detected in the four patients have not been previously reported. In conclusion, four novel mutations of the FVII gene in Taiwanese, including two missense mutations in exon 8, one point mutation at the exon 6 splice site and one deletion in exon 1A, were identified.

Spinal anaesthesia and dysfibrinogenaemia

We report the case of a 34-year-old woman who presented to the delivery unit at 36 weeks' gestation with spontaneous rupture of membranes. She had a triplet pregnancy following in vitro fertilisation. An elective caesarean section was performed under spinal anaesthesia 4h after admission. The patient had a massive postpartum haemorrhage in the recovery area at which time she mentioned that she was known to have 'low fibrinogen'. Further investigation showed that she suffered from dysfibrinogenaemia, as did several members of her family. We can find no reported cases of the use of central neural blockade in a patient with untreated dysfibrinogenaemia. Central neural blockade is often considered contraindicated in patients with disorders of fibrinogen; there were fortunately no neurological sequelae following spinal anaesthesia in this patient.

Markers of risk for preterm delivery

Clinical and experimental evidence indicate that PTD results from four primary pathogenic mechanisms: activation of the maternal or fetal HPA axis; amniochorionic-decidual or systemic inflammation; decidual hemorrhage; and, pathologic distention of the myometrium. Each of these four pathways has a distinct epidemiological and clinical profile, and unique biochemical and biophysical pathways initiating parturition, but shares a common final biochemical pathway involving myometrial activation and stimulation, and enhanced genital tract protease activity promoting PPROM and cervical change. Traditional methods of predicting women at risk relying on obstetrical history or symptoms and epidemiological risk factors are neither sensitive nor specific. Recent approaches to predicting PTD, including sonographic measurement of cervical length and biochemical assays for hCG, cytokines, fFN, MMPs, estrogens, and CRH, are more sensitive than traditional methods. Moreover, given the heterogeneous, interactive etiopathogeneses of PTD, multiple biochemical markers should not only increase sensitivity and specificity, but also permit the detection of the relative contribution of each pathogenesis to the overall risk of PTD.

Females with von Willebrand disease: 72 years as the silent majority

The monthly challenge of menstruation as well as the haemostatic challenge of childbirth postpartum renders more females than males symptomatic with von Willebrand disease. Among vWD patients, the obstetrical and gynaecological morbidity is certainly more pronounced in Type 2,3 patients compared to Type 1 patients, but even in the latter group there is a high proportion of menorrhagia with associated anaemia, loss of time from work/school and the use of hysterectomy for ultimate control of bleeding. Despite the well known adage of the "gestational palliation" of vWD, there is a high proportion of postpartum haemorrhage in Type 1 patients also especially after the first 24 h after delivery. This may occur despite normalization of the factor VIIIc level in the third trimester, particularly in Type 2,3 patients. With the increasing availability of intranasal/subcutaneous DDAVP that could be readily administered at home for menorrhagia, there recently has been ongoing efforts internationally to determine the prevalence of vWD in females presenting with menorrhagia with a prevalence of 17% combined from two studies of 180 patients total. Issues remain regarding the optimal dose/schedule of intranasal/subcutaneous DDAVP for menorrhagia and the relative efficacy of antifibrinolytic agents. The proper role of oral contraceptives and danazol also deserves further study in vWD patients with menorrhagia. In sum, a comprehensive care approach in females with vWD is warranted analogous to the successful model of care of male haemophiliacs with the intent to (a) reduce unnecessary surgical interventions for menorrhagia, (b) improve the quality of life during menses and (c) optimize peri-partum management.

The role of pharmacologic agents in blood conservation

Pharmacologic agents are welcome therapeutic weapons in the fight to conserve blood. The goals of drug therapy cross a broad spectrum of potential areas. Blood-conserving pharmacologic agents are aimed at 1) increasing blood production, 2) decreasing blood loss during active bleeding, and 3) preventing the breakdown of the formed fibrin clots. In this article, the author reviews the mechanisms of action, dosing, and adverse effects of these agents. The role of pharmacologic agents in blood conservation is significant because these agents have been shown to decrease transfusion requirements and provide significant cost savings.

Congenital coagulopathies and pregnancy: report of four pregnancies in a factor X-deficient woman

Pregnancy in women with congenital coagulation factor deficiencies has been associated with adverse fetal outcomes. Recurrent spontaneous abortions, placental abruptions, and premature births are reported, the exact reasons for which are not clear, and management of such patients continues to be a challenge. We reviewed the outcome of four pregnancies in a patient with factor X deficiency, and looked at the effect of factor replacement therapy on pregnancy. Her first two pregnancies resulted in the birth of extremely premature babies at 21 and 25 weeks of gestation, both of which died in the neonatal period. The patient was treated with fresh frozen plasma for acute bleeding episodes during these pregnancies. In addition during her second conception she was given factor IX complex [Konyne] prophylactically, but only in the latter half of her pregnancy. During her next two pregnancies she was treated early on during pregnancy, with prophylactic replacement of factor X. She delivered healthy babies at 34 and 32 weeks of gestation, and they are both doing well. We therefore suggest possible mechanisms by which aggressive prophylactic factor support in a female with severe congenital coagulopathy, may improve on fetal outcome.

Placental thrombi and other vascular lesions. Classification, morphology, and clinical correlations

Vascular lesions, most often mediated by thrombi, are second only to infections as a cause of fetal injury in the later weeks of pregnancy. In our experience many pathologists who examine placentas fail to conduct a proper search for vascular lesions and some even fail to recognize those exposed by their examination. This review is intended to define the typical clinical background or circumstances that suggest the presence of significant vascular problems, to define techniques calculated to display them well, and to identify criteria for diagnosis. Further research is needed to evaluate the prevalence of maternal and fetal hypercoagulable states and thrombi as a cause of fetal injury.

Oral estrogens decrease bleeding time and improve clinical bleeding in patients with renal failure

PURPOSE

A prolonged bleeding time is associated with platelet dysfunction and clinical bleeding in patients with renal failure. Parenteral estrogens have been shown to shorten the prolonged bleeding time in patients with chronic renal failure, although the mechanism of action is unknown. We conducted a study to evaluate the efficacy of oral conjugated estrogens in this setting.

PATIENTS AND METHODS

Four patients with renal failure, prolonged bleeding time, and clinical bleeding were given 50 mg of conjugated estrogen (Premarin) daily.

RESULTS

Bleeding time normalized in two cases and was reduced to less than 50% of the pretreatment value in one of the remaining two cases. Bleeding stopped in all patients within two days. Ten dialysis patients with prolonged bleeding time were randomized to a course of 50 mg of Premarin daily or placebo. The bleeding time in all five patients in the Premarin group normalized or decreased to below 50% of the pretreatment value after 7.0 +/- 4.2 days of therapy. The bleeding time did not normalize in the five patients treated with placebo. No side effects attributable to therapy were reported.

CONCLUSION

We conclude that orally administered conjugated estrogens effectively improve the bleeding tendency in patients with chronic renal failure.

Epidural anaesthesia and von Willebrand's disease

A case is described of a primiparous patient with Von Willebrand's type 1 disease and diabetes who presented at 36 weeks' gestation for Caesarean section. This was performed under epidural anaesthesia in the absence of any coagulation disorder. The effects of pregnancy on coagulation factors in this disorder are discussed.

Acute coagulopathy in pregnancy

Pregnancy alters both the fibrinolytic system and coagulation cascade. In addition, pregnancy presents unique triggering mechanisms for DIC. Management of DIC in pregnancy should include removal of the triggering mechanism, blood, and factor replacement. Inherited coagulation defects, while rarely resulting in bleeding diathesis in the pregnant patient, do require monitoring of maternal factor levels. Genetic counseling should be offered to all patients with inheritable coagulation disorders.

Platelet function and factor VIII in uremia

We studied platelet function and plasma factor VIII in 15 healthy individuals and 41 uremic patients to evaluate the effect of dialysis on the hemostatic defect in uremia. Platelet counts and bleeding times were normal in all subjects. Platelet retention on glass beads was significantly reduced in all uremic patients. Platelet aggregation induced by collagen and ADP were significantly reduced in uremic patients on conservative therapy. ADP-induced platelet aggregation was normal but collagen-induced aggregation remained abnormal in hemodialysis (HD) patients. Both ADP- and collagen-induced aggregation were normal in patients on continuous ambulatory peritoneal dialysis (CAPD). FVIII: C was normal in all uremic patients. Both FVIII:vWF and FVIII R:Ag were significantly elevated in all uremic patients. In conclusion, platelet function was significantly defective and FVIII:vWF and FVIII R:Ag significantly elevated in uremia. HD and CAPD did not influence factor VIII levels or function nor did they improve platelet retention. Platelet aggregation improved partially on HD and completely on CAPD.

Conjugated estrogens for the management of bleeding associated with renal failure

Bleeding is a major complication of uremia. Both cryoprecipitate and desmopressin effectively shorten the prolonged bleeding time and favorably influence clinical bleeding, but the former carries the risk of transmitting blood-borne infectious diseases, and both cryoprecipitate and desmopressin have a short duration of action. Preliminary evidence has suggested that estrogens may be useful, and we therefore performed a randomized, double-blind, crossover trial comparing the effect of conjugated estrogens with that of placebo on hemorrhagic tendencies and the bleeding time in six patients with uremia who were on maintenance hemodialysis. Five daily infusions of placebo or conjugated estrogens were administered at the beginning of one-month trial periods. Estrogen shortened the bleeding time in all six patients. The effect was detectable six hours after the first infusion, reached its maximum in all patients between days 5 and 7, and lasted for 14 days. By day 16 after the last infusion, the bleeding time had returned to base line in four of the six patients. No side effects were noted during or after estrogen infusion. Estrogens did not influence the circulating level of von Willebrand factor or change its multimeric structure. Moreover, the defective platelet aggregation and thromboxane formation observed in the patients were not corrected by estrogens. We conclude that conjugated estrogens are an adequate alternative to cryoprecipitate or desmopressin for the treatment of bleeding associated with renal failure, especially when a longer duration of action is needed and immediate onset of the effect is not essential. The mechanism of action of estrogens remains to be clarified.