Hereditary antithrombin deficiency in pregnancy - severe thrombophilic disorder as a danger for mother and foetus

SETTING: In the article, we remember the role of antithrombin (AT) in hemostasis, escalation of AT-potential with heparin and difficulties with monitoring the effectiveness of LMWH therapy (low molecular weight heparin) in patients with AT deficiency. We pay most of our attention to hereditary AT deficiency and its thromboembolic risk in pregnancy. METHODS: In the introduction, the principle of AT function, its two main domains and the regulation of synthesis are cleared. We describe the causal mutations of hereditary AT deficiency in SERPINC1 gen and the relation to a thromboembolic risk. The general recommendations for patients with hereditary AT deficiency and pregnant women are mentioned. As the risk of thromboembolic disease is escalated in pregnancy, the LMWH should always be considered. There has been frequently observed that patients with AT deficiency do not elevate anti-Xa-levels when standard prophylactic LMWH doses are used. This fact well illustrates that heparin without AT may not inhibit the active coagulant factors efficiently enough. Therefore, if a high thromboembolic risk in the patient's anamnesis is present, the LMWH dosing should be escalated. In individual cases, concomitant administration of an antithrombin concentrate to the heparin treatment is recommended at the time of delivery or in the case of deep venous thrombosis. In this article, three cases of unusual pregnancy in patients with different types of AT deficiency are reported. The case reports are summarized from the Department of Hematology at Hospital Kolín, the Centre of Hemostasis and Thrombosis at Institute of Hematology and Blood Transfusion in Prague and from cooperating obstetrical departments in the Czech Republic. RESULTS: We demonstrated the threat of hereditary AT deficiency in three case reports. In one case, the estimated risk of thromboembolism ­ type I of AT-deficiency (quantitative) ­ was in a good correlation with real peripartal complications. In the next two cases with different types of AT deficiency, we showed surprising courses of complicated pregnancies. CONCLUSION: As it has been shown, it is not safe to estimate the risk of thromboembolism on the base of causal mutation for AT deficiency. For present clinical practice, we should still remember AT deficiency as a potentially very dangerous thromboembolic disorder for mother and fetus; thus, excellent cooperation of an obstetrician and a hematologist is necessary.

Economic evaluation of rFVIIa high initial dose compared to rFVIIa standard initial dose in patients with haemophilia with inhibitors using the Czech HemoRec registry.

INTRODUCTION: In the treatment of bleeds in haemophilia patients with inhibitors, a high initial dose of recombinant Factor VIIa (rFVIIa) provides at least equal efficacy and a similar safety profile to a standard initial dose. However, no pharmacoeconomic comparison between these dosing regimens has previously been performed. Here, we assess the pharmacoeconomics of high (>120 µg/kg) versus standard (≤120 µg/kg) initial rFVIIa dose in inhibitor patients and the impact of time to treatment initiation on costs and outcomes. METHODS: In a retrospective analysis, observational data on bleed characteristics, rFVIIa treatment, hospitalizations and outcomes were extracted from the Czech Republic HemoRec registry. Crude comparisons and generalized linear regression modelling (GLM; correcting for patient differences) were performed to compare costs and outcomes between the high and standard initial dosing groups. RESULTS: Of 314 rFVIIa-treated bleeding episodes (12 inhibitor patients), most were spontaneous joint bleeds and 67.5% were treated with a high initial dose. In the crude comparison, high initial rFVIIa dosing was associated with a lower mean number of doses needed to achieve haemostasis compared with standard dosing (p<0.001), but higher total dose and costs (p ≤ 0.008). However, regression analyses revealed that high initial dose was associated with similar costs (p=0.891) and a shorter time to bleeding resolution (p=0.014). Increasing time to treatment initiation increased both time to bleeding resolution and total costs. CONCLUSION: Compared with a standard dose, a high initial rFVIIa dose may improve treatment outcomes without increasing costs. Early treatment initiation may reduce treatment costs.

Fibrinogen Sumperk II: dysfibrinogenemia in an individual with two coding mutations.

Fibrinogen­a 340-kDa glycoprotein­plays a crucial role in blood coagulation, platelet aggregation, wound healing, and other physiological processes. A mutation in fibrinogen may lead to congenital dysfibrinogenemia,a rare disease characterized by the functional deficiency of fibrinogen. About 580 cases of abnormal fibrinogens have been reported worldwide; thereof 335 cases in the fibrinogen Aa chain[1]. To our knowledge, only five cases of abnormal fibrinogens with two mutations [2­6] and one case of two different mutations in the same family [7] have been described earlier. A 52-year-old female was examined for bleeding. Routine hemostasis screening resulted in a diagnosis of dysfibrinogenemia. Functional testing revealed prolonged fibrin polymerization, prolonged lysis of the clot, abnormal fibrin morphology,and fibrinopeptides release. Genetic analysis showed two heterozygous nonsense mutations­previously described mutation AaGly13Glu and a novel mutation Aa Ser314Cys. The mutation Aa Gly13-Glu was found in her brother and niece, but there was no evidence in either of the mutation Aa Ser314Cys. While mutation Aa Gly13Glu is responsible for abnormal fibrinopeptide release and prolonged thrombin time, the novel mutation Aa Ser314Cys seems to affect fibrin morphology and fibrinolysis.