Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 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

"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 effect of beta 2glycoprotein I (beta 2GPI) and human monoclonal anticardiolipin antibody (aCL) on the protein S/C4b-binding protein (C4BP) system was evaluated. The binding of C4BP to protein S was assessed by ELISA in the presence of beta 2GPI with/without human monoclonal aCL. beta 2GPI downregulated the binding between S and C4BP significantly. Human monoclonal aCL abolished the beta 2GPI inhibitory effect in a calcium (Ca++) independent fashion. In separate experiments, the reactivity of aCL towards protein S in the presence or absence of beta 2GPI and cardiolipin was investigated. Monoclonal aCL bound to protein S only in the presence of a combination of beta 2GPI and cardiolipin. This binding was Ca++ dependent. These findings suggest that human monoclonal aCL increases the affinity of C4BP for protein S, and that protein S may represent one of the targets for aCL when combined with beta 2GPI and cardiolipin. Both issues may explain acquired free protein S deficiency and the attendant risk of thrombosis in patients with aCL.
Lupus 1997
PMID:Effect of beta 2glycoprotein I and human monoclonal anticardiolipin antibody on the protein S/C4b-binding protein system. 917 18

A 41-year-old woman with complete protein S (PS) deficiency who developed diffuse proliferative lupus nephritis is reported. She was referred to our hospital with nephrotic syndrome and thrombocytopenia. Her medical history included colorectostomy and amputation of the extremities because of repeated thrombotic episodes during her teens without any evidence of systemic lupus erythematosus. The diagnosis of PS deficiency was made from the patient's clinical course, undetectable serum PS in either the active or inactive form, normal protein C activity, and no evidence of the antiphospholipid syndrome. However, there was no definitive family history. A depressed level of complements and a positive antinuclear acid antibody suggested a diagnosis of systemic lupus erythematosus. The patient had a rapidly progressive course and died of disseminated intravascular coagulation. An autopsy showed generalized thrombotic lesions and diffuse proliferative lupus nephritis on both ordinal light and immunoperoxidase microscopy. Our observations suggest that PS-deficient patients may have a hyperinflammatory response.
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PMID:A 41-year-old woman with protein S deficiency and diffuse proliferative lupus nephritis: is protein S deficiency associated with a hyperinflammatory response? 918 80

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

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

Sixteen patients with Moyamoya disease and four with quasi-Moyamoya disease were investigated in order to elucidate the presence of thrombophilia. The assay system for diagnosing thrombophilia consisted of assessing both the activity and antigen levels of antithrombin III, protein C, protein S, fibrinogen and plasminogen as well as detecting lupus anticoagulants. The analysis revealed that one third (four definite cases and three quasi-cases) of the examined patients demonstrated either congenital or acquired thrombotic tendency. Protein C deficiency was found in two definite cases and in two quasi-cases among whom one quasi-case was identified to have a hereditary type I Protein C deficiency. Protein S deficiency was found in one definite case and in one quasi-case. Type II plasminogen deficiency was found in one quasi-case, and lupus anticoagulant was present in one quasi-case. Based on these findings, an evaluation of thrombophilia should thus be performed when both diagnosing and treating suspected cases of Moyamoya disease.
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PMID:Thrombophilia found in patients with moyamoya disease. 940 44

The pathophysiological basis of blood coagulation includes hemostatic causes and thrombophilia (protein C deficiency, protein S deficiency, APC resistance, plasminogen deficiency, antithrombin III deficiency, hyperhomocystinemia, lupus anticoagulans and anticardiolipin antibodies). The effect of female sexual steroids on coagulation has been observed: ethinyl estradiol produced an increased risk of thromboembolism. Also, there was a pronounced increase of fibrin division products among users of higher EE doses. The effect of gestagens on coagulation was found to be contradictory. The risk of thrombosis as related to oral contraceptives (OCs) was investigated in several studies. Desogestrel and gestoden-containing OCs produced a higher incidence of thrombosis than levonorgestrel-containing pills. A WHO multinational case-control study was carried out in 21 centers and 17 countries during 1989-93, including a total of 1143 cases and 2998 controls. The risk of thrombosis was 2-3 times higher among women using gestoden or desogestrel-containing OCs than those using LNG-containing OCs. Similarly, there was a 1.58 increased risk according to a case-control study using data from England and Germany. A 1995 study of 700 medical practices in Great Britain involving 238,130 women showed increased risk for gestoden (1.8) and desogestrel (1.9). Another 1995 study used the data of 697,000 women from 398 practices in England and registered 116 cases of thromboembolism. There was a risk three times higher for all ovulation inhibitors among cases compared to controls, as well as a pregnancy risk 5.9 times higher. Nonetheless, no definitive conclusion can be drawn from all of these epidemiological studies, which could challenge the prevailing view on contraceptive behavior.
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PMID:[Contraceptive agents and risk of thrombosis]. 941 70


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