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)

We examined the incidence of thrombophilia in deep vein thrombosis (DVT). Of 38 cases, we found 4 cases of protein C abnormality, 2 cases each of protein S abnormality and lupus anticoagulant, 1 case of antithrombin III abnormality. The total incidence was 23.7%, whereas only 2 cases (6.2%) of plasminogen abnormality were found among 32 healthy individuals. The incidence of thrombophilia was apparently higher among patients with DVT than that of healthy subjects, although the incidence of Japanese DVT was lower than that of Caucasian DVT, as previously reported. By SSCP analysis in one case of protein C abnormality, we demonstrated an abnormality of exon 9-3. To establish laboratory diagnosis of thrombophilia, it is recommended that (1) severe liver diseases, DIC, and oral anticoagulant be ruled out, (2) abnormality be confirmed by repeated examination, (3) family study determine inheritance mode, if possible. It was strongly suggested that laboratory examination of thrombophilia should be routinely applied to cases of venous thrombosis including DVT, not only for diagnostic interest but also for appropriate treatment of these cases.
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PMID:[Laboratory diagnosis of congenital thrombophilia]. 913 96

Great progress has been made within the past 10 years in characterizing, assaying, and describing mechanism(s) of action in vitro of antiphospholipid antibodies (a-PL Abs); three prominent members are reagin, anticardiolipin antibodies (a-CL Abs), and the lupus anticoagulants (LAC). The major focus of this review is on basic and current biochemical and immunologic research. First, the biochemistry, structural composition, and sources of anionic and dipolar ionic (zwitterionic) phospholipids are discussed together with several serum antibodies directed to these phospholipids. Cardiolipin, the most acidic phospholipid (net negative charge of 2 at pH 7.0) has been historically important as an antigen for testing reagin in syphilis serology, and currently is part of the antigenic composition used in the Venereal Disease Research Laboratory (VDRL) tests. In this connection, the chronic biological false-positive test for syphilis and the LAC are discussed in association with autoimmune disorders such as systemic lupus erythematosus. Second, a naturally occurring plasma anticoagulant in vitro and a critical cofactor for binding of purified autoimmune a-CL Abs to cardiolipin is considered, the beta 2-glycoprotein I (beta 2-gpI). This single-chain plasma polypeptide is highly glycosylated, has 326 amino acids, a molecular weight of 50 kD, and is characterized by repeating amino acid motifs or domains that structurally resemble multiple loops. The highly cationic C-terminal fifth domain binds to anionic phospholipids. The beta 2-gpI is a member of the short consensus repeat superfamily of proteins, and is compared with other proteins with similar domains. Third, experiments are detailed for defining LAC and distinguishing it from other a-CL Abs. Cofactors are also associated with LAC and include beta 2-gpI, prothrombin, protein C, protein S, tissue factor, and factor XI. Thus, LAC antibodies are heterogeneous, and no individual assay can detect all LACs. Because patients with syphilis and other infectious diseases have no cofactor associated with a-CL Abs, their plasma LACs are negative. The a-CL Abs found in infection are not associated with the clinical features of the antiphospholipid syndrome. LAC assays are important because of the pathogenetic association with clinical observations of venous and arterial thrombosis, thrombocytopenia, and recurrent fetal loss. Finally, reports leading to development of currently used direct solid-phase enzyme-linked immunosorbent assays (ELISA) for testing a-PL Abs are outlined; these developments have greatly increased understanding of the basic immunology of target antigens and their respective antibodies. Of significance, a-CL Abs cross-react with other anionic phospholipids. Additionally, the results of these assays led to the realization that high levels of circulating a-PL Abs over long periods are associated with a number of clinical problems now known collectively as the antiphospholipid syndrome.
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PMID:Antiphospholipid antibodies: basic immunology and assays. 914 49

Widespread cutaneous necrosis (WCN) associated with antiphospholipid antibodies is rare. Its mechanisms have yet to be elucidated, and there are no well-established guidelines for its management. We describe a woman who had two episodes of WCN related to surgical manipulation for urinary tract obstruction and urinary tract infection. Lupus anticoagulant was always positive. In the second episode anticardiolipin antibodies were elevated, and protein C levels were temporarily decreased. We found only ten previously reported cases of WCN associated with antiphospholipid antibodies, none of which were related to surgical manipulation.
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PMID:Widespread cutaneous necrosis and antiphospholipid antibodies: two episodes related to surgical manipulation and urinary tract infection. 914 72

Patients with a family history of thrombosis, early-onset or recurring thrombosis, thrombosis at unusual sites, or warfarin-induced skin necrosis should be investigated for a possible underlying inherited hypercoagulable disorder. These include AT-III deficiency, protein C and S deficiencies, and APC resistance. Many patients should also be evaluated for the antiphospholipid syndrome, an acquired disorder. Functional assays are more useful than immunologic assays for diagnosing AT-III deficiency, protein C and S deficiencies, and APC resistance. A molecular probe is now available for the abnormal factor V most often responsible for APC resistance. Testing for the antiphospholipid syndrome involves assays for the lupus anticoagulant and anticardiolipin antibodies. AT-III and protein C concentrates are now available for short-term therapy. Long-term prophylactic administration of warfarin may have to be considered for some symptomatic patients with proven abnormalities, especially after more than one thrombotic event. While the management of asymptomatic persons remains controversial, the use of prophylactic anticoagulation should be anticipated for trauma, surgery, pregnancy, or other high-risk situations.
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PMID:The hypercoagulable state. Who, how, and when to test and treat. 915 17

"Antiphospholipid" antibodies (aPL) are a heterogenous group of autoantibodies with clinical importance because of their association with thrombotic events, both venous and arterial. Traditionally, aPL have been assayed using phospholipid-dependent tests and are classified as lupus anticoagulants and anticardiolipin antibodies (ACA), based on the method of detection. Most antibodies associated with the aPL syndrome and detected in standard assays are actually directed against two phospholipid-binding plasma proteins, beta 2 glycoprotein I and prothrombin. These antibodies can also be detected in immunoassays (ELISA) utilizing purified protein antigens, in the absence of phospholipids. The main advantage of beta 2 GPI-ELISA compared with conventional cardiolipin-ELISA appearing from initial clinical studies is greater specificity for the aPL syndrome, due to (i) ignorance of "authentic" ACA that interact directly with cardiolipin; (ii) detection of species specific anti-beta 2 GPI antibodies poorly reactive with bovine beta 2 GPI in the cardiolipin-ELISA. Other proteins proposed as target antigens of aPL are protein C, protein S, annexin V, high- and low-molecular weight kininogens, the latter being involved in the binding of antibodies to phosphatidylethanolamine. The possibility that particular autoantibodies (or combinations of autoantibodies) explain the observed clinical spectrum of the aPL syndrome is attractive, but much remains to be learned about their pathogenicity and origin in order to improve diagnosis and therapy.
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PMID:[New targets of antiphospholipid antibodies]. 916 56

The antiphospholipid syndrome is defined as the association between the presence of antiphospholipid antibodies, detected as anticardiolipin antibodies and/or lupus anticoagulant, and a history of either arterial or venous thrombosis and/or recurrent pregnancy loss. Because thrombosis may occur in virtually any organ system, diagnosing the antiphospholipid syndrome and taking appropriate anticoagulation measures are important considerations in all medical specialties. Antiphospholipid antibody-associated thrombosis tends to recur. Antithrombotic prophylaxis to prevent recurrences is therefore needed. Prophylaxis in individuals with circulating antiphospholipid antibodies who have no history of thrombosis is still controversial. Although direct evidence for a pathogenetic role of antiphospholipid antibodies in the development of thrombosis is still lacking, recent studies suggest that it is causative rather than coincidental. New insights on the possible mechanisms leading to thrombosis were provided by the discovery of the serum cofactor (beta2-GPI), a coagulation inhibitor which is required for binding of anticardiolipin antibodies to cardiolipin. More recently, patients with antiphospholipid antibodies were found to possess autoantibodies directed against other coagulation factors, including prothrombin, protein C and protein S. Future studies should clarify whether these different antigenic specificities are associated with particular clinical events and assess the risk of thrombosis associated with the presence of antiphospholipid antibodies in asymptomatic individuals.
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PMID:The clinical significance of antiphospholipid antibodies. 918 33

The effect of antiphospholipid antibodies (aPL) on the action of activated protein C (APC) was examined in 32 patients: 19 with lupus anticoagulant (LA), 6 with anticardiolipin antibodies (aCL), and 7 with LA and aCL. Eighteen patients had a ratio of activated partial thromboplastin time (APTT) with APC to APTT without APC (APTT ratio) <2.06 (cut-off level) and no factor V Leiden mutation; these patients showed APC-resistance (APC-R) phenotype. The mean prolongation of APTT after addition of APC in a control group was 45.3 seconds, with a lower limit of 31.4 seconds. Only 3 of the 18 patients with low APTT ratio had a prolongation of <31.4 seconds; they were classified as true APC-R phenotype, whereas the other 15 patients were classified as spurious APC-R. Of the 3 patients with true APC-R, 2 had deep venous thrombosis, 1 with pulmonary embolism, and the third had recurrent abortion. Of the other 15 patients, 2 had had ischemic stroke, 1 had recurrent abortion, and 12 were asymptomatic. Circulating APC level was measured in 14 of the 18 aPL patients with a low APTT ratio; it was lower than the normal lower limit in 4 patients and within the lower limit in 2. Three of the 4 patients with reduced APC levels had a history of thrombosis. We conclude that patients with aPL who show APC-R phenotype due to a low APTT ratio without the factor V Leiden mutation can be classified into two groups: true and spurious APC-R phenotype. Since those with true APC-R phenotype could have greater thrombotic risk, adequate classification of these patients is important. Moreover, aPL can sometimes interfere with the activation of protein C, thus reducing the circulating levels of APC, and this could constitute another thrombotic risk factor.
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PMID:Activated protein C resistance phenotype in patients with antiphospholipid antibodies. 928 Jan 48

We developed a novel assay using human thrombomodulin (TM), which detected overall abnormalities in the protein C anticoagulant pathway (PC pathway). This assay indicates the degree of inhibition of prothrombinase by TM, which is represented as the percentage of prothrombinase inhibition by 25 ng/ml of TM, termed PIP25 (Prothrombinase Inhibition Percentage). We examined PIP25 in plasma samples from patients with systemic lupus erythematosus (SLE) with or without lupus anticoagulant (LA), patients with Behcet's disease (BD), and patients with miscellaneous thrombotic vasculitis and compared these with the PIP25 of plasma samples from healthy volunteers in Japan. The PIP25S were significantly lower in SLE alone (35.5 +/- 12.8%, P = 0.036) and SLE with LA (33.0 +/- 13.3%, P = 0.030) and BD (33.3 +/- 13.4%, P = 0.010) than those in healthy volunteers (43.5 +/- 10.7%). There was no significance between healthy PIP25 and those with miscellaneous thrombotic vasculitis (44.2 +/- 8.4%, P = 0.823). These results suggest that the abnormalities of the protein C anticoagulant pathway were present in patients with SLE(LA) and BD.
Lupus 1997
PMID:Abnormalities in the protein C anticoagulant pathway detected by a novel assay using human thrombomodulin. 930 62

We examined thrombophilic mechanisms and outcome in 54 patients with deep-vein thrombosis (DVT), who were otherwise apparently healthy and aged < or = 50 years. Patients were followed up 6 years (median) after a confirmed first DVT between 1987-1992 with no known predisposing illnesses. Patients were traced through the hospital registry and compared with 25 matched controls. Tested thrombophilic mechanisms were either genetic (activated protein C [APC] resistance; anti-thrombin III deficiency [ATIII]; protein C or protein S deficiency [PC, PS]) or acquired (lupus anti-coagulant [LAC]/anti-cardiolipin antibodies [ACA]; subsequent diagnosis of cancer). Twenty-nine DVT patients attended for full studies. The remaining 25 were interviewed by phone and none had a reported neoplastic disease, confirmed by their hospital records and the National Cancer Registry. These patients' demographics, risk factors and subsequent course were similar in all respects to the studied group. In the control group, APC resistance was the only coagulopathy found (1/25, 4%), and it was also the most common abnormality among DVT patients (8/29, 28%) (p = 0.009). Three DVT patients had LAC/ACA (10%) and one each, ATIII, PC and PS deficiencies (3.3% each). No malignancy was encountered during a follow-up of 7.9 +/- 5.7 years. Circumstantial risk factors were found in 52% of the patients, 21% had a family history of DVT, and 41% had recurrent DVT. These characteristics were not significantly different when DVT patients with and without coagulopathy were compared.
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PMID:Causes and outcome of deep-vein thrombosis in otherwise-healthy patients under 50 years. 930 63

We have established a system for etiological analysis of thrombophilia which includes assays of antithrombin III, protein C, protein S, plasminogen, fibrinogen, heparin cofactor II and lupus anticoagulants as well as gene analysis. The analysis conducted on 115 patients with venous thrombosis, arterial thrombosis and small vessel thrombosis revealed that forty-one patients(36% of the examined patients) were accompanied with decreased activities of protein S, protein C, antithrombin III and plasminogen. Eleven candidate causal mutations were found by gene analysis. These studies indicate that a comprehensive examination is instrumental in identifying and confirming the etiology in patients with thrombophilia.
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PMID:[Etiological analysis of thrombophilia]. 939 41


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