Gene/Protein Disease Symptom Drug Enzyme Compound
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The clinical picture of venous or arterial thrombosis in the presence of circulating antiphospholipid antibodies is referred to as the antiphospholipid syndrome. A 5-month-old baby girl who was quite healthy so far was referred to our clinic with irritability, vomiting, and abdominal distension for 30 hours. Surgical exploration exposed a gangrenous ileal segment about 15 cm long. The postoperative period was unremarkable. Investigation to identify the risk factors for mesenteric thrombosis found anticardiolipin antibodies (isotype Ig G) and decreased protein C level. Protein S and antithrombin III were within normal levels. Hb electrophoresis results showed no HbS, and neither Factor V Leiden nor prothrombin 20210 mutations were detected. Eight months postoperatively, anticardiolipin antibodies were found within normal levels. Lupus anticoagulant, ds DNA, and ss DNA were negative. Direct coombs test and protein C, C3, and C4 were also within normal levels. She had no thrombotic episode in the 24 months postoperatively, although no anticoagulant medication was administered. To the authors' knowledge this case is the first report of segmental intestinal infarction in transient antiphospholipid syndrome in the pediatric population.
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PMID:Transient antiphospholipid syndrome in an infant with segmental small bowel infarction. 1469 90

Systematic evaluations of anemia, thrombocytopenia, and coagulopathy are essential to identifying and managing their causes successfully. In all cases, clinicians should evaluate RBC measurements alongside WBC and platelet counts and WBC differentials. Multiple competing factors may coexist; certain factors affect RBCs independent of those that affect WBCs or platelets. Ideally, clinicians should examine the peripheral blood smear for morphologic features of RBCs, WBCs, and platelets that provide important clues to the cause of the patient's hematologic disorder. Thrombocytopenia arises from decreased platelet production, increased platelet destruction, or dilutional or distributional causes. Drug-induced thrombocytopenias present diagnostic challenges, because many medicines can cause thrombocytopenia and critically ill patients often receive multiple medications. If they suspect type II HIT, clinicians must promptly discontinue all heparin sources, including LMWHs, without awaiting laboratory confirmation, to avoid thrombotic sequelae. Because warfarin anticoagulation induces acquired protein C deficiency, thereby exacerbating the prothrombotic state of type II HIT, warfarin should be withheld until platelet counts increase to more than 100,000/microL and type II HIT is clearly resolving. The presence of a consumptive coagulopathy in the setting of thrombocytopenia supports a diagnosis of DIC, not TTP-HUS, and is demonstrated by decreasing serum fibrinogen levels, and increasing TTs, PTs, aPTTs, and fibrin degradation products. Increasing D-dimer, levels are the most specific DIC parameter and reflect fibrinolysis of cross-linked fibrin. Elevated PTs or a PTTs can result from the absence of factors or the presence of inhibitors. Clinicians should suspect factor inhibitors when the prolonged PT or aPTT does not correct or only partially corrects following an immediate assay of a 1:1 mix of patient and normal plasma. In addition to factor inhibitors, antiphospholipid antibodies (e.g., lupus anticoagulant) can produce a prolonged aPTT that does not correct with normal plasma but is overcome by adding excess phospholipid or platelets. Paradoxically, a tendency to thrombosis, not bleeding, accompanies lupus anticoagulants and the antiphospholipid antibody syndrome. Transfusion of red blood cells, platelets, or plasma products is sometimes warranted, but clinicians must carefully weigh potential benefits against known risks. In critically ill patients, administering RBCs can enhance oxygen delivery to tissues. Among euvolemic patients who do not have ischemic heart disease, guidelines recommend a transfusion threshold of HGB levels in the range of 6.0 to 8.0 g/dL; patients who have HGB that is at least 10.0 g/dL are unlikely to benefit from blood transfusion. The use of rHuEPO to increase erythropoiesis offers an alternative to RBC transfusion, assuming normal, responsive progenitor cells and adequate iron, folate, and cobalamin stores. Future research should examine whether clinical outcomes from rHuEPO use in critically ill patients are important and cost-effective. Because platelets play an instrumental role in primary hemostasis, platelet transfusions are often important in managing patients who are bleeding or at risk of bleeding with thrombocytopenia or impaired platelet function. Platelet transfusions carry risks, and decisions to transfuse platelets must consider clinical circumstances. Most important, platelet transfusions are generally contraindicated if the underlying disorder is TTP or type II HIT, because platelet transfusion in these settings may fuel thrombosis and worsen clinical signs and symptoms. Plasma products can correct hemostasis when bleeding arises from malfunction, consumption, or underproduction of plasma coagulation proteins. Choice of plasma product for transfusion depends on clinical circumstances. FFP is the most commonly used plasma product to correct clotting factor deficiencies, particularly coagulopathies that are attributable to multiple clotting factor deficiency states as in liver disease, DIC, or warfarin anticoagulation. PCC or rFVIIa that is administered in small volumes may provide advantages over FFP when coagulopathies require quick reversal without risk of volume overload. Factor concentrates can replace specific factor deficiencies. Recombinant FVIIa bypasses inhibitors to factors VIII and IX and vWF. Use of rFVIIa in managing hemostatic abnormalities from severe liver dysfunction; extensive surgery, trauma, or bleeding; excessive warfarin anticoagulation; and certain platelet disorders requires further study to determine optimal and cost-effective dosing regimens. Recombinant activated protein C reduces mortality from severe sepsis that is associated with organ dysfunction in adults who are at high risk for death (APACHE scores of at least 25). In severe sepsis, levels of protein C decrease, as do fibrinogen and platelet levels. Because of its anticoagulant effect, however, drotrecogin alfa may induce bleeding. Guidelines for drotrecogin alfa use must take into account bleeding risks.
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PMID:Critical issues in hematology: anemia, thrombocytopenia, coagulopathy, and blood product transfusions in critically ill patients. 1471 Jun 93

Over a 5-year period, we investigated 77 consecutive patients (36 males, 41 females, mean age 40.9 years) referred to our hospital with the diagnosis of CNS vasculitis. Extensive workup including MRI, echocardiography, laboratory tests, angiography ( n=53), and biopsies at appropriate sites ( n=26) was performed based on individual history and symptoms. Prominent symptoms were stroke ( n=61), encephalopathy ( n=14), and headaches ( n=2). Vasculitis was finally diagnosed in 13 patients (17%) including isolated angiitis of the CNS ( n=3), giant cell arteritis ( n=4), and septic arteritis ( n=3). Thirty-two patients (42%) presented noninflammatory vasculopathies including moyamoya ( n=6), Sneddon's syndrome ( n=5), dissection ( n=4), CADASIL ( n=2), and collagen vascular disease ( n=9). Coagulopathy was found in 14 cases (18%) including antiphospholipid syndrome ( n=8) and APC resistance ( n=4). Other causes were cardiogenic embolism ( n=8), multiple sclerosis ( n=5), and migraine stroke ( n=3). Only a minority of patients referred for evaluation of suspected CNS vasculitis actually present with inflammatory vascular disease. Main differential diagnosis includes noninflammatory vasculopathies, coagulopathies, and cardiac disease. Since septic processes may be responsible for the symptoms, "blind" treatment with immunosuppressive agents should be strictly avoided.
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PMID:[Diagnosis and differential cerebral vasculitis diagnosis]. 1477 Feb 79

Thrombophilia is characterized by clinical tendency to thrombosis or molecular abnomalities of hemostasis that predisposes to thromboembolic disease. Hereditary thrombophilia may be due to antithrombin deficiency, or protein C or protein S deficiency. More recently, other molecular abnormalities have been described: activated protein C resistance due to factor V Leiden, G 20210 A polymorphism on the prothrombin gene, increased factor VIII plasma levels or hyperhomocysteinemia. Acquired thrombophilia is frequently associated with the antiphospholipid syndrome characterized by thrombosis and presence of lupus anticoagulant or phospholipid-binding antibodies. In some cases, no molecular abnormality is found despite recurrent thrombosis observed in patient and his/her family. This situation can be considered as clinical thrombophilia.
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PMID:[Definition of thrombophilia]. 1502 78

Inherited and acquired thrombophilia are associated with recurrent pregnancy loss. Recently, an increased risk for thromboembolic disease was described for patients with elevated coagulation factor VIII, but it is unknown whether there is also an association to early pregnancy loss. We therefore evaluated the relation between recurrent early pregnancy loss and levels of coagulation factor VIII. We enrolled 49 unrelated Caucasian women with a history of 2-6 early pregnancy losses and 48 healthy controls, who had delivered at least one term infant and had never experienced pregnancy loss. We determined factor V Leiden-, G20210A prothrombin-, MTHFR C677T- and A1298C-gene mutations, levels of antithrombin, protein C, protein S, factor VIII, C-reactive protein and antiphospholipid antibodies. There was a significantly higher rate of pregnancy losses in women with Antiphospholipid Syndrome (p = 0.043). Furthermore, plasma levels of coagulation factor VIII were significantly higher in cases than in controls (130.5 IU/dl +/- 25.4 vs 119.5 IU/dl +/- 24.1; p = 0.032) and appeared independent of C-reactive protein (R = 0.146, p = 0.323 in cases; R = -0.028, p = 0.850 in controls). The relative risk for recurrent pregnancy loss in women with factor VIII levels above 151 IU/dl (90(th) percentile of controls) was 2.5 (0.7 - 8.9, 95 percent confidence interval), for levels above 156 IU/dl (95(th) percentile of controls) 3.9 (0.8 - 20.0, 95 percent confidence interval). Elevated maternal plasma levels of coagulation factor VIII tend to be associated with an increased risk for recurrent early pregnancy loss.
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PMID:Elevated coagulation factor VIII and the risk for recurrent early pregnancy loss. 1504 30

The antiphospholipid syndrome (APS) is associated with thrombosis and fetal death but the pathologic mechanisms are poorly understood. Since endothelial protein C receptor (EPCR) plays a role in the anticoagulant system and in placental development, we hypothesized that anti-EPCR autoantibodies may be involved in clinical manifestations of APS and in fetal loss. The levels of immunoglobulin M (IgM) and IgG anti-EPCR autoantibodies were analyzed by enzyme-linked immunosorbent assay (ELISA) in 43 patients with APS and 43 controls. Anti-EPCR levels were higher in APS patients than in controls. Interestingly, one of the IgM anti-EPCR autoantibodies inhibited the generation of activated protein C on endothelium. Since markedly high anti-EPCR levels were found in women with fetal death, 87 patients with a first episode of unexplained fetal death were subsequently analyzed and their anti-EPCR levels were compared with 87 matched controls. We found that anti-EPCR autoantibodies constitute an independent risk factor for a first fetal death episode: the adjusted odds ratios (ORs) for anti-EPCR autoantibodies above the 95th percentile were 23.0 (95% confidence interval [CI], 2.0-266.3) for IgM and 6.8 (95% CI, 1.2-38.4) for IgG. Anti-EPCR autoantibodies can be detected in APS patients and are independent risk factors for fetal death.
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PMID:Autoantibodies against EPCR are found in antiphospholipid syndrome and are a risk factor for fetal death. 1515 78

Antiphospholipid syndrome is considered to be a cause of an acquired hypercoagulable state leading to stroke and transient ischemic attack. Antiphospholipid antibodies (aPL) comprise a heterogeneous group of autoantibodies. Among them, lupus anticoagulant (LA) and beta 2-glycoprotein I dependent anticardiolipin antibody (beta 2-GPI aCL) are important and commonly measured. Recently, LA has been considered to be closely related to phosphatidylserine anti-prothrombin antibody. APL is an independent risk factor for first-ever ischemic stroke and a prognostic marker of recurrent stroke. The precipitating factors for the occurrence of stroke are the presence of beta 2-GPI-dependent aCL, a GPL aCL level of more than 40, and the simultaneous presence of lupus anticoagulant. Several mechanisms are believed to be involved in the thrombotic process in patients with antiphospholipid antibodies. Human activated protein C functions as a potent anticoagulant in human plasma by inhibiting the activity of coagulation cofactors Va and VIIIa. Activation of protein C is impaired in patients with aPL. Recently, the presence of aPL has been considered to be contributory factor for the development of atherosclerotic lesions. Transgenic mouse lacking the LDL receptor develop accelerated arteriosclerosis upon immunization with beta 2-GPL Several therapeutic options are available for the prevention of ischemic stroke in patients with aPL, such as antiplatelet, anticoagulant, and immunosuppressive therapy. The rate of recurrence in patients undergoing antiplatelet and anticoagulation combination therapy was found to be lower than that in patients receiving other forms of therapy. The WARSS-APASS collaborative study showed that there was no difference in the recurrence rate between aPL patients receiving antiplatelet or anticoagulation therapy alone. APL has been investigated in other neurological disorders such as multiple sclerosis, chorea, migraine and convulsion. The association of aPL with multiple sclerosis remains debatable. APL could be a contributory factor for the development of convulsion, but not for migraine.
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PMID:[Neurological aspects in antiphospholipid syndrome]. 1515 54

The purpose of the present study was to determine whether using an extended panel of laboratory tests increases the detection of a hypercoagulable state in patients with ocular thromboses. Twenty consecutive patients with ocular thromboses (vein, artery, or choriocapillaris occlusions) underwent testing for activated protein C resistance/factor V Leiden, prothrombin G20210A, lupus anticoagulant, anticardiolipin antibodies, hyperhomocysteinemia, and deficiencies of protein C, protein S, and antithrombin. For each patient, we selected two age-matched and gender-matched individuals without ocular thromboses as controls. Sixteen of the 20 patients (80%) had one or more laboratory tests that supported a hypercoagulable condition. Prothrombin G20210A (P < 0.02) and hyperhomocysteinemia (P < 0.0006) were significantly more frequent in ocular thrombosis patients compared with controls. The most common condition was antiphospholipid antibody syndrome, present in 40% of patients (confirmed by repeat testing at least 6 weeks later), but this did not reach statistical significance compared with the controls. No patients with ocular thromboses had hereditary abnormalities of protein S, protein C, or antithrombin. In conclusion, an extended panel of laboratory tests improved the detection of a hypercoagulable state in ocular thromboses. Testing for homocysteine, antiphospholipid antibodies, and the prothrombin G20210A mutation should be considered in patients with ocular thromboses.
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PMID:Prothrombin gene mutation G20210A, homocysteine, antiphospholipid antibodies and other hypercoagulable states in ocular thrombosis. 1520 87

Disturbances of the embryo-maternal interaction, i.e. impaired implantation, are seen in only a minor fraction of couples. These malfunctions become evident as recurrent spontaneous abortions (RSA), or repetitive implantation failure (RIF) in cases with IVF or ICSI procedures. The antiphospholipid syndrome (APL) is the only consensus-defined syndrome associated with RSA (anticardiolipin antibodies and/or lupus anticoagulant plus clinical symptoms). Since antiphospholipid antibodies directly interfere with hemostasis (increased coagulation), heparin is an established treatment option in these cases resulting in unequivocal benefits. There is no defined antibody syndrome in RIF even if it may be assumed that it exists. Conclusive evidence for a benefit of heparin (and aspirin) in this situation is lacking as well. However, the majority of investigations including our own experience indicate that anticoagulation may be useful. Besides the extensively studied anticardiolipin antibodies, other - by far less thoroughly investigated - antiphospholid antibodies have been described. So far it is unclear if heparin may exert positive effects in women carrying these antibodies. Autoreactive immune processes may also become apparent by the emergence of further antibodies, such as antinuclear (ANA), thyreoglobulin (TGA) and thyreoperoxidase antibodies (TPO) etc. However, there is no established definition of a syndrome associated with these antibodies, TGA and TPO probably being the most relevant. - Most studies in this area including our own experience indicate that heparin may be a useful. The detection or autoantibodies per se is probably not of pathophysiological relevance if there is no ongoing pathological activation of the immune system. However, an acute autoimmune response associated with irregular antibodies may represent the pathophysiological basis of a reproductive autoimmune failure syndrome. In these cases, immune-equilibrating interventions appear to be more appropriate than heparin therapy. - Coagulation disorders, namely thrombophilia, are a frequent cause of RSA and probably RIF as well, the most relevant being antithrombin deficiency, Factor V Leiden and prothrombin mutations. Deficiencies of protein S, protein C and factor XII and XIII are of minor importance. There is a varying degree of evidence for a benefit of heparin/aspirin in these syndromes. Heparin not only reduces the abortion rate but also lowers the risk for developmental retardation, premature birth and preeclampsia. - The effects of heparin are not restricted to anticoagulation. It is directly or indirectly (e.g. via heparan sulfate proteoglycans or heparin-binding EGF) involved in the adhesion of the blastocyst to the endometrial epithelium and the subsequent invasion. Actually, prolonged heparin treatment (14 days) resulted in an increased pregnancy rate in our patient population. Shorter courses of heparin where not effective.
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PMID:Effectivity of heparin in assisted reproduction. 1521 Apr 1

Patients with ischemic stroke are sometimes found to have an underlying inherited (deficiency of protein C, protein S, antithrombin III, activated protein C resistance, prothrombin gene mutation, hyperhomocysteinemia) or acquired thrombophilia (lupus anticoagulant and anticardiolipin antibodies, hyperhomocysteinemia). Patient selection for thrombophilia screening is, therefore, a frequent question in managing patients with ischemic stroke. In this review we discuss patient selection and timing for laboratory tests for thrombophilia screening in stroke patients based on a literature review and we calculated overall costs per year in Germany for testing patients older than 18 years with an ischemic stroke of undetermined cause. As there is a lack of studies comparing anticoagulation with antiplatelet therapy in patients with diagnosed thrombophilia, laboratory screening for thrombophilia even in a selected group of patients with cryptogenic ischemic stroke remains of questionable value at present. An exception appears to be testing for lupus anticoagulant and anticardiolipin antibodies in younger patients with suspected antiphospholipid syndrome (two positive test results necessary), because anticoagulation seems to be superior to aspirin in patients with antiphospholipid syndrome.
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PMID:[Thrombophilias in patients with ischemic stroke. Indication and calculated costs for evidence-based diagnostics and treatment]. 1533 41


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