Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The patient is a 23 y.o. man with acute nephritis and bleeding at presentation. Laboratory data consistent with the diagnosis of systemic lupus erythematosus. A lupus anticoagulant was found: tissue thromboplastin inhibition test (TTIT) ratio 3.4; diluted Russell viper venom (DRVV) ratio 2.6. Hypoprothrombinemia (FII:C less than 1%; FIIR:Ag 5%) was present; prothrombin survival time (FII concentrate infusion 60 U/kg): t1/2 approximately to 9 hours. A prothrombin antibody was identified: it is not neutralizing but forms an immunecomplex with prothrombin. The antibody was characterized as IgG2, IgA, k, lambda. The prothrombin survival time indicates that the hypoprothrombinemia is due to the clearance of the prothrombin-antiprothrombin complex in vivo.
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PMID:Prothrombin-antibody coexistent with lupus anticoagulant (LA): clinical study and immunochemical characterization. 210 92

The investigators have evaluated the frequency and manifestations of anti-prothrombin antibodies in patients with the lupus anticoagulant. Thirty-one of 42 patients with lupus anticoagulants associated with a variety of underlying conditions (74%) had evidence on crossed immunoelectrophoresis of anti-prothrombin antibodies. Twenty-four of 25 patients with an activated partial thromboplastin time exceeding 50 seconds and 14 of 15 patients with a prothrombin time exceeding control by more than two seconds had demonstrable anti-prothrombin antibodies. Three of the 31 patients with anti-prothrombin antibodies had essentially no measurable plasma prothrombin, a presumed result of accelerated clearance of prothrombin/prothrombin antibody complexes. Each of these patients had bled abnormally. The remaining patients with anti-prothrombin antibodies had neither substantial hypoprothrombinemia nor hemorrhagic manifestations, which confirms the non-neutralizing property of anti-prothrombin antibodies associated with the lupus anticoagulant. Since lupus anticoagulant immunoglobulins are known to react with phospholipids, the high prevalence of antibodies binding prothrombin led us to test the hypothesis of antibody polyreactivity. Adsorption of three lupus anticoagulant plasmas with insolubilized prothrombin markedly diminished evidence of both prothrombin/prothrombin antibody complexes and anticoagulant activity. Eluates of the insolubilized prothrombin contained IgG that not only bound prothrombin but possessed lupus anticoagulant activity.
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PMID:Anti-prothrombin antibodies and the lupus anticoagulant. 245 97

A 66-year-old man with the lupus anticoagulant-hypoprothrombinemia syndrome was treated with cyclophosphamide and prednisone to correct a factor II deficiency prior to elective major surgery. Whereas the lupus anticoagulant activity persisted, functional factor II levels normalized and he underwent surgery without a bleeding diathesis. Immunosuppressive therapy may temporarily normalize factor II levels in patients with the lupus anticoagulant-hypoprothrombinemia syndrome and reduce the risk of excessive hemorrhage. The disparate response of the lupus anticoagulant and hypoprothrombinemia to immunosuppression suggests that the lupus anticoagulant did not directly cause the hypoprothrombinemia.
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PMID:Correction of hypoprothrombinemia by immunosuppressive treatment of the lupus anticoagulant-hypoprothrombinemia syndrome. 311 49

Lupus anticoagulants (LA) are associated with various forms of thrombotic events. Of particular interest to obstetrics is the association with placental infarcts and habitual abortion. In the case described a near full-term viable infant was delivered subsequent to four early miscarriages. However, the mother had then developed an antifactor II antibody leading to grave hypoprothrombinemia with bleeding tendency, indicating efficient autoanticoagulation. This natural experiment indicates that these patients should receive anticoagulation during pregnancy, possibly in combination with steroids to depress the LA level.
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PMID:Lupus anticoagulant: a unique case with lupus anticoagulant and habitual abortion together with antifactor II antibody and bleeding tendency. 313 8

Antibodies that bind prothrombin without neutralizing its coagulant activity were demonstrated in the plasma of two patients with the acquired hypoprothrombinemia-lupus anticoagulant syndrome. The first patient's plasma contained less than 1% prothrombin activity and no detectable prothrombin antigen. The second patient's plasma contained about 6% of both prothrombin activity and antigen. Neither patient's plasma neutralized the prothrombin coagulant activity of normal plasma or of purified prothrombin added in vitro. Nevertheless, double immunodiffusion studies and binding experiments utilizing 125I-prothrombin demonstrated the presence of prothrombin antibodies in each patient's plasma. A Scatchard analysis of the binding data obtained with different concentrations of 125I-prothrombin and the first patient's plasma indicated the presence of a high affinity antibody, apparent Kd approximately 10(-10)M, and a lower affinity antibody, apparent Kd approximately 10(-9)M. Studies utilizing purified cleavage products of prothrombin suggested that the antibodies were directed against an epitope or epitopes located on the carboxyl-terminal, latent thrombin segment of the prothrombin molecule. We postulate that the acquired hypoprothrombinemia in these two patients and in other reported patients with the acquired hypoprothrombinemia-lupus anticoagulant syndrome stems from rapid clearance from the circulation of prothrombin antigen-antibody complexes.
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PMID:A mechanism for the hypoprothrombinemia of the acquired hypoprothrombinemia-lupus anticoagulant syndrome. 640 77

Prothrombin deficiency has been known to occur in association with lupus inhibitors for over 25 years. We studied 21 patients with lupus inhibitors and found that four of five with prothrombin deficiency and ten of 16 with quantitatively normal prothrombin had abnormal prothrombin crossed-immunoelectrophoresis (CIEP) characterized by material moving slower in the first dimension of electrophoresis than normal prothrombin. In two patients with prothrombin deficiency, all prothrombin measured by quantitative assay and all slow-moving material on CIEP were removed by treatment with Staphylococcal protein A (SPA). These patients had free antibody, which bound to normal plasma prothrombin, forming larger amounts of slow-moving material on CIEP. A third patient with prothrombin deficiency had only partial removal of prothrombin after SPA treatment. Two patients with quantitatively normal prothrombin had all slow-moving material on CIEP and about one fourth of the prothrombin by quantitative assay removed by SPA treatment. There was no correlation among the strength of the inhibitor, the presence of a "cofactor effect," and the prothrombin abnormality. These data suggest that heterogeneous antiprothrombin antibodies, with or without prothrombin deficiency, are present in the majority of patients with lupus inhibitors.
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PMID:Abnormal prothrombin crossed-immunoelectrophoresis in patients with lupus inhibitors. 643 5

Twelve surgical procedures were performed in eight patients with circulating lupus anticoagulant. Bleeding complications were noted intra and postoperatively in three patients, either with an associated hypoprothrombinemia and/or thrombocytopenia. Five patients in whom only circulating lupus anticoagulant was found had an uneventful intra and postoperative course. It is concluded that the presence of lupus anticoagulant, when unassociated with other hemostatic defects, is not a contraindication for surgery.
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PMID:Surgery in patients with circulating lupus anticoagulant. 679 5

The lupus anticoagulant is a well-described in vitro phenomenon that may be associated with arterial and venous thrombotic episodes. The lupus anticoagulant is never accompanied by a hemorrhagic diathesis unless it is associated with a second coagulation abnormality such as thrombocytopenia or hypoprothrombinemia. The lupus anticoagulant-hypoprothrombinemia syndrome is now a well-defined entity that may cause a severe, life-threatening hemorrhagic diathesis. The hypoprothrombinemia in this syndrome is the result of rapid clearance of prothrombin-antiprothrombin antibody complexes by the reticulo-endothelial system. The cause of antiprothrombin antibody formation is unknown. The authors describe a recent experience with a patient with this syndrome who initially had recurrent, life-threatening gastrointestinal bleeding. They were able to demonstrate hypoprothrombinemia and the presence of prothrombin-antiprothrombin antibody immune complexes. The patient was treated with prednisone, with correction of the bleeding disorder; however, the patient had resultant death from thrombosis. A literature review of the past 30 years as it relates to the discovery and treatment of this phenomenon is included.
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PMID:Case report: the lupus anticoagulant-hypoprothrombinemia syndrome. 817 28

Acquired inhibitors of coagulation causing bleeding manifestations are rare in children, particularly without an associated underlying disorder such as autoimmune disease. We describe an otherwise healthy 1 1/2-year-old girl who had extensive spontaneous bruising and prolonged bleeding from venipuncture sites. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were prolonged, with evidence of an immediate-acting inhibitor. Thrombin clotting time, fibrinogen, and platelets were normal. Biologic assay of factors II, V, VII, and X were all low, with increasing values at higher dilutions. However, by immunoassay and/or chromogenic assays, only factor II was reduced. An antibody which failed to neutralize prothrombin activity in vitro was detected against radiolabeled prothrombin. Coagulation studies normalized in parallel with clinical recovery and disappearance of the antibody. This case demonstrates acute hypoprothrombinemia-lupus anticoagulant syndrome as a rare presentation of bleeding diathesis in a healthy young child.
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PMID:Transient hemorrhagic diathesis associated with an inhibitor of prothrombin with lupus anticoagulant in a 1 1/2-year-old girl: report of a case and review of the literature. 860 32

We report here experiments on how lupus anticoagulant antibodies (LA IgG) that react with prothrombin bind to surface phospholipid and affect prothrombin's affinity for surface phospholipid and activation to thrombin. LA IgG was purified by protein A chromatography from the plasma of 16 patients of whom four had associated hypoprothrombinemia and 10 had experienced thrombosis. Many LA IgG bound, in the absence of phospholipid and calcium, not only to immobilized prothrombin but to both prothrombin 1 and fragment 1, which established at least an oligoclonal origin of LA IgG. No LA IgG bound to thrombin. Although prothrombin and Ca2+ were required to support binding of LA IgG to immobilized phosphatidylserine (PS), prothrombin at higher concentrations inhibited binding, presumably by competing with prothrombin/LA IgG complexes for PS binding sites. Prothrombin 1, which cannot bind to PS, also inhibited binding of many LA IgG to PS, presumably by forming competing soluble prothrombin 1/LA IgG complexes. Despite their ability to react with prothrombin independent of phospholipid, LA IgG enhanced binding of prothrombin to immobilized phospholipid and to cultured human umbilical vein endothelial cells. Prothrombin bound with LA IgG to the surface of endothelial cell monolayers could be activated to thrombin after supernatant prothrombin and LA IgG were washed away. The relation is discussed of these observations to a hypothesis that LA IgG mediated concentration of prothrombin on cell surface phospholipid represents a mechanism by which LA IgG could increase thrombotic risk.
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PMID:Mechanism and effects of the binding of lupus anticoagulant IgG and prothrombin to surface phospholipid. 894 52


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