Safety of therapeutic doses of tinzaparin during pregnancy.

BACKGROUND/AIMS: Low molecular weight heparin is recommended for the treatment of venous thromboembolism (VTE) during pregnancy. However, there are few reliable data regarding the safety of therapeutic doses of tinzaparin in this setting. The objective of this study was to assess the safety of once-daily therapeutic doses of tinzaparin for the treatment of VTE during pregnancy. METHODS: A retrospective study was carried out in 3 tertiary care centres in France, from 1998 to 2009, including consecutive pregnant women who received once-daily therapeutic doses of tinzaparin (175 IU/kg/day). RESULTS: We analyzed 87 pregnancies in 83 women, representing a total of 13,320 patient-days of treatment. Live-birth rate was 97.8%, with one case of miscarriage (<20 weeks of gestation) and one case of intrauterine foetal death (≥20 weeks). There was no antenatal major bleeding. Major bleeding occurred in 4 women during an emergency caesarean section. No case of heparin-induced thrombocytopenia and no maternal death were reported. There was no neonatal haemorrhage and no case of congenital abnormality. VTE recurred on treatment in one patient and after treatment interruption for several days in 2 other patients. CONCLUSIONS: These results support the safety of once-daily tinzaparin at therapeutic dose for the treatment of VTE during pregnancy.

Functional characterization of fibrinogen Bicêtre II: a gamma 308 Asn-->Lys mutation located near the fibrin D:D interaction sites.

The effects of the gamma-308 Asn-->Lys substitution of fibrinogen Bicêtre II on clot formation, structure and properties were determined to elucidate the role of this part of the molecule in fibrin polymerization. This process was followed by measurement of turbidity, and the structure and biophysical characteristics of the clots were studied by permeation, scanning electron microscopy, and rheological techniques. Turbidity studies revealed an increased lag period and greater final turbidity for fibrin BII clots, indicating impaired oligomer formation. By permeation it was found that BII clots had greater network porosity, four times more than that of the control. The clot architecture visualized by scanning electron microscopy was similar to that of control clots with pore size and fiber diameter slightly increased. BII clots had a stiffness decreased by more than half, and an increased loss tangent, a measure of the inelastic deformation of the clot. All these results suggest a disruption of the proper alignment of fibrin monomers during oligomer formation. Consistent with these results, fibrin cross-linking by adding the physiological concentration of factor XIII to the purified protein showed that gamma and alpha chain cross-linking was impaired in BII clots. This amino acid substitution defines distinctive effects on the surface of the D:D interaction sites that are reflected in the clot structure and functional properties.

Perioperative management of hemostasis for surgery of benign hepatic adenomas in patients with glycogen storage disease type ia.

The development of hepatocellular adenomas in the liver of patients with glycogen storage disease type I is a well-known complication of the disease. Surgical procedures and perioperative managements described so far have reported persistent and important morbidity. We report here a series of six patients (three males and three females) who underwent hepatic resection, and we propose a new hemostatic management protocol comprising glucose infusion, corticosteroids, desmopressin, and antifibrinolytic drugs, used to prevent efficaciously hepatic hemorrhage due to glycogen storage disease (GSD) platelet dysfunction.

Obstetrical Complications and Outcome in Two Families with Hereditary Angioedema due to Mutation in the F12 Gene.

Backgroud. Hereditary angioedema (HAE) is characterized by recurrent swelling of the skin, the abdomen (causing severe acute pain), and the airways. A recently discovered type caused by mutations in the factor XII gene (designated as HAE type III) occurs mainly in women. Estrogens may play an important role, but few obstetrical complications have been reported. Case. We report the symptoms and obstetrical complications of women in two families with HAE attributable to the p. Thr328Lys mutation in the F12 gene. Clinical manifestations included acute and severe maternal abdominal pain, with transient ascites, laryngeal edema, and fetal and neonatal deaths. Patients had normal C4 levels and a normal C1 inhibitor gene. Administration of C1-inhibitor concentration twice monthly decreased the attack rate in one mother, and its predelivery administration (1000 U) led to the delivery of healthy girls. Conclusions. Obstetricians and anesthesiologists should be aware of this rare cause of unexplained maternal ascites and in utero or fetal death associated with edema.

Increased levels of hemostatic proteins are independent of inflammation in glycogen storage disease type Ia.

OBJECTIVES: Glycogen storage disease type Ia (GSD-Ia), a congenital deficiency of hepatic glucose-6-phosphatase activity, is often associated with hyperproteinemia. To document the mechanism of hyperproteinemia, the proteins of the hemostatic system were analyzed according to their site of synthesis: hepatocyte, endothelial cell, or both. The role of inflammation was investigated by the measurement of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) levels in plasma. METHODS: Twenty-seven patients with GSD-Ia were evaluated, as were 14 patients with other types of GSD and 30 healthy control subjects. Of the 41 patients with GSD, 15 also had hepatic adenoma (14 patients with GSD-Ia and 1 with GSD type III). RESULTS: In patients with GSD-Ia, there was a two-fold increase in all hepatocyte-synthesized proteins (i.e., factor VII, protein C, C4b binding protein) compared with control subjects and patients with other types of GSD. The proteins with mixed endothelial and hepatocyte origin (i.e., antithrombin and protein S) also were significantly increased but to a lesser extent. In contrast, the mean concentration of von Willebrand factor, which is exclusively synthesized in endothelial cells, was normal, as was the concentration of TNF-alpha and IL-6. CONCLUSIONS: These results suggest that the hyperproteinemia of GSD-Ia (including hemostatic proteins) is attributable to hepatocyte dysfunction and not related to an inflammatory process.