Duplication of the inferior vena cava in a patient presenting for IVC filter placement.

Given the complex embryogenesis of the inferior vena cava (IVC), anatomic variations are commonly encountered. Duplication of the IVC occurs in up to 2.8% of the population. Though asymptomatic, a duplicated IVC has important clinical implications when attempting caval filtration. We present the case of a 45- year-old male with factor V leiden and protein C deficiency, who required cessation of warfarin anticoagulation in preparation for cervical laminectomy. The patient had a duplicated IVC and required placement of a caval filter in each IVC.

Use of Factor V Leiden genetic testing in practice and impact on management.

PURPOSE: To assess the use of the genetic test for Factor V Leiden in clinical practice, physician adherence to national and local guidelines, and impacts of test results on patient management. METHODS: Chart review of all patients tested for Factor V Leiden during a 1-year period (2003) in a large nonprofit health care system (group health) (n = 272). RESULTS: The test for Factor V Leiden was most often used in nonacute outpatient settings by primary care practitioners, in combination with other tests for procoagulant disorders. Testing was performed more broadly than recommended: 61% of tests met American College of Medical Genetics guidelines, 46% of tests met CAP guidelines, and 37% of tests met group health internal guidelines. The most common rationale for testing was to explain a clinical event (58%). Patient management was modified more often in heterozygotes (54%) than in those with normal results (13%) (P < 0.0001). CONCLUSIONS: The uptake of the test for Factor V Leiden has not followed existing recommendations. Genetic risk information was used to influence patient management in the absence of supporting evidence related to health outcomes. These results underscore the importance of further research concerning effective prevention and treatment strategies for patients with genetic risk to help translate genetic risk information into improved health outcomes.

Increased acquired activated protein C resistance in unselected patients with hematological malignancies.

BACKGROUND: We have previously found that activation of coagulation in patients with various hematological malignancies was apparently not initiated by tissue factor (TF). Acquired activated protein C (APC) resistance may be another mechanism responsible for such hypercoagulation, and has been demonstrated in patients with solid tumors, but not in patients with hematological malignancy. OBJECTIVE: To investigate acquired APC resistance in a hypercoagulable cohort of patients with hematological malignancies. PATIENTS/METHODS: Blood samples from 93 patients with acute myeloid leukemia (AML), chronic lymphatic leukemia, multiple myeloma, or non-Hodgkin's lymphoma, were analyzed before start and after completion of cancer therapy. APC resistance was measured using calibrated automated thrombography. The APC sensitivity ratio (APC-SR) was calculated as the ratio of the endogenous thrombin potential (ETP) determined in plasma probed with either APC or buffer. RESULTS: Untreated patients were found to have higher APC-SR than healthy controls, and patients with AML had higher APC-SR as compared to the other diagnoses, both findings being consistent with acquired APC resistance. The acquired APC resistance was partly ameliorated with cancer treatment. Decreased levels of protein S and TF pathway inhibitor were inversely correlated to APC resistance. CONCLUSIONS: APC resistance may contribute to the hypercoagulable state in hematological malignancies.

Activated protein C resistance and factor V Leiden: a review.

CONTEXT: Factor V Leiden (FVL) is the most common heritable cause of venous thrombosis. It is caused by a single nucleotide substitution resulting in an R506Q missense mutation, resulting in factor V resistance to activated protein C (APC) inactivation. Carriers of FVL have an increased susceptibility to venous thrombosis, which is further increased in the presence of other genetic or environmental risk factors. OBJECTIVE: To review the biology, clinical findings, laboratory detection methods, and screening recommendations for patients with the FVL mutation. DATA SOURCES: PubMed review of published literature and online information. CONCLUSIONS: FVL remains an important heritable cause of hypercoagulability since its discovery more than 10 years ago. Clinical suspicion should be high in cases of unexplained venous thrombosis. APC resistance and FVL mutation can be diagnosed with high sensitivity and specificity with use of clotting time-based functional assays and genetic assays, respectively, allowing for evidence-guided clinical decision making regarding the benefit of long-term anticoagulation.

Mesenteric artery occlusion secondary to activated protein C resistance: a life-threatening combination.

We present a case of mesenteric ischemia in a 32-year-old woman. The rarity of this potentially fatal condition in this age group, the diagnostic and therapeutic challenges associated with such a condition, and secondary causes that must always be investigated are highlighted. In this case, activated protein C resistance resulted in thrombosis of the superior mesenteric artery and subsequent bowel ischemia.

The transjugular intrahepatic portosystemic stent-shunt (TIPS) as rescue therapy for complete Budd-Chiari syndrome and portal vein thrombosis.

We present a 40-year-old female patient with epigastric pain, ascites, and progressive liver failure, caused by Budd-Chiari syndrome (BCS) with thrombotic occlusion of the right and middle hepatic veins. As underlying diseases, essential thrombocythemia and resistance to activated protein C (APC) due to heterozygote factor V Leiden were found. Initial therapy with heparin caused thrombocytopenia (HIT) type II culminating in thrombosis of the last patent left hepatic vein and further deterioration of liver function. The decision against a surgical shunt and liver transplantation by our surgeons on the basis of the risks involved, prompted us to insert a transjugular intrahepatic portosystemic stent-shunt (TIPS). There was no measurable flow signal in the doppler sonography of the portal vein presumably due to thrombosis. A further evaluation with magnetic resonance tomography and angiography was impossible due to movement artefacts. TIPS initially served as a diagnostic tool allowing direct angiography-diagnosed thrombosis of the portal vein, the superior mesenteric and the splenic vein respectively. However, insertion of the TIPS shunt and subsequent fragmentation led to an effective hepatic decompression and full recanalisation of the portal vein. In the present case TIPS simultaneously allowed the diagnosis of portal vein thrombosis and served as rescue therapy of complicated Budd-Chiari syndrome. The potential development of HIT type II should be kept in mind when heparin is given, especially to patients with thrombophilia.

Activated protein C resistance and pregnancy loss.

Activated protein C resistance is a thrombophilia with an established role in producing thrombosis which more recently has been implicated in the pathogenesis of pregnancy loss. This review will analyse recent literature to evaluate this association and address the gestation and type of pregnancy loss.

Congenital and acquired activated protein C resistance.

Resistance to the anticoagulant action of activated protein C, APC resistance, is a highly prevalent risk factor for venous thrombosis among individuals of Caucasian origin. In most cases, APC resistance is associated with a single missense mutation in the gene for coagulation factor V (FV (Leiden)), which predicts the replacement of Arg (506) with a Gln at one of the cleavage sites for APC in factor V. Factor V is a Janus-faced protein with dual functions, serving as an essential nonenzymatic cofactor in both pro- and anticoagulant pathways. Procoagulant factor Va, generated after proteolysis by thrombin or factor Xa, is a cofactor to factor Xa in the activation of prothrombin, whereas anticoagulant factor V, generated after proteolysis by APC, functions as a cofactor in the APC-mediated degradation of FVIIIa. The FV (Leiden) mutation affects the anticoagulant response to APC at two distinct levels of the coagulation pathway, as it impairs degradation of both activated factor V and activated factor VIII, the latter effect inasmuch as FVLeiden is a poor APC cofactor. Several other genetic traits, some of them quite common, are known to affect the anticoagulant response to APC, but none of them cause the same severe APC-resistance phenotype as FV (Leiden) and their importance as risk factors for thrombosis is unclear. A poor APC response may also result from acquired conditions, some of which are clearly involved in the pathogenesis of venous thrombosis. Venous thrombosis is a typical multifactorial disease, the pathogenesis of which involves multiple gene-gene and gene-environment interactions. In many patients with severe thrombophilia, APC resistance is found as a contributing risk factor.

The effect of factor V Leiden carriage on maternal and fetal health.

Factor V Leiden is a common genetic mutation that predisposes its carriers to venous thromboembolism. When combined with the hypercoagulable state that is characteristic of pregnancy, there is an increased risk of severe and recurrent pregnancy complications. Factor V Leiden is the most common cause of primary and recurrent venous thromboembolism in pregnancy. Factor V Leiden carriage has consistently been shown to increase the risk of early onset gestational hypertension and HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets) in pregnancy. Maternal carriage of factor V Leiden is also associated with severe placental abruption and fetal growth disturbances. Although it is unclear whether factor V Leiden causes an increased risk of first trimester miscarriage, it is associated with stillbirth and placental infarction. Patients with venous thromboembolism or severe pregnancy complications should be tested for factor V Leiden and other inherited and acquired thrombophilia. Therapeutic heparin is required for acute thromboembolic events in pregnancy. Patients with factor V Leiden and a previous venous thromboembolism may, according to their level of risk, be offered either prophylactic or therapeutic heparin. The role of antithrombotic therapy in the prevention of severe pregnancy complications remains unclear.

Protein A immunoadsorption in a pregnant woman with habitual abortion.

The role of antibodies in the occurrence of recurrent spontaneous miscarriage is well known. However there are many controversial issues in the management of habitual abortion. This paper describes the effect of Protein A immunoadsorption on serum levels of these antibodies and its impact on a case of a successfully treated woman in a outpatient department without need for a central venous catheter. Given the favourable clinical results described in our paper we think it may be relevant for some worse cases in clinical practice and will interest your readers.

Activated protein C resistance and lupus anticoagulant in pregnancy.

Thrombophilias, both inherited and acquired, have been reported to be associated with thromboembolic events and severe obstetric complications. This case report examines the case of a patient with two thrombophilias, activated protein C resistance secondary to Factor V Leiden mutation and lupus anticoagulant.