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)

Racial differences in stroke are known to exist with persons in the black race having a higher morbidity, mortality and incidence of stroke compared to whites. We evaluated coagulation factors in black and white stroke patients and compared the results between races. D-dimer was elevated more frequently in blacks than whites to a statistically significant degree. There were non-significant trends for blacks to have a positive lupus anticoagulant, low protein C and protein S, higher platelet factor 4, and hyporesponsive platelets to 10 microM epinephrine. The significance of these findings in understanding racial differences in stroke is discussed.
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PMID:Racial differences in coagulation studies in stroke. 135 61

Most people who experience venous thrombosis have normal hemostasis. Some people have inherited deficiencies of protein C, protein S, and antithrombin iii. They tend to have deep venous thrombosis which increases their risk for pulmonary emboli. Some acquired disorders which predisposes people to thrombosis include defective fibrinolysis which often occurs after surgery or infection, Trousseau's syndrome (excessive coagulant activity linked with adenocarcinoma), and lupus anticoagulant which is an immunoglobulin G or M antibody directed against negatively charged phospholipids. Hormones and probably not a dilution effect reduces free and bound protein S levels during pregnancy. Functional protein S activity is still 40-50% below normal levels 1-3 days after delivery. This decrease appears to protect against bleeding but does have venous thrombosis and pulmonary emboli during pregnancy as side effects. Non-oral-contraceptive (OC) users have greatly higher protein S levels than do OC users (28.6 mcg/ml vs. 24.3 mcg/ml; p.005) which gives more credence to the belief that hormones are responsible for the fall in protein S activity during pregnancy. OCs reduce free and total protein S levels almost 20%. Smoking may even further reduce these levels in women during pregnancy and who use Ocs. Women who have had venous thrombosis should not use OCs. Physicians should also consider family history especially age of affected family member, severity of thrombotic episodes, and the clinical setting. They should look for an underlying abnormality in patients who develop thrombosis while using OCs. If thrombosis develops during pregnancy, physicians should call for a venogram, venous duplex scanning, and, if required, invasive tests. The most sensible treatment is intravenous heparin for 5-7 days then therapeutic doses of heparin. Heparin therapy should stop before delivery and be reinstituted shortly thereafter and continued throughout the postpartum period. Physicians should take extra precautions when performing surgery on an OC user.
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PMID:Recent advances in understanding clotting and evaluating patients with recurrent thrombosis. 141 44

The overall incidence per year of deep vein thrombosis is about one per thousand, but may be much higher in the presence of certain clinical risk factors such as advanced age, immobilization, surgical procedures, pregnancy, puerperium, use of oral contraceptive agents and malignancy. Moreover, homocystinuria, nephrotic syndrome, systemic lupus erythematosus and hematological disorders such as paroxysmal nocturnal hemoglobinuria or myeloproliferative syndromes predispose to thrombotic disease. Evaluation of the patient with thromboembolism should include detailed history, clinical examination and laboratory investigation to exclude these secondary thrombophilic states. Primary or hereditary thrombophilia is suspected mainly in patients suffering from (venous) thromboembolism at an early age (< 45 years), especially if recurrent and/or familial thrombosis is present. Hereditary thrombophilia may be due to deficiency of antithrombin III, protein C, protein S or plasminogen, some other defects being less well-established prethrombotic risk factors. These currently recognized primary prethrombotic molecular defects are found in 10 to 30% of patients with idiopathic thromboembolism. In the majority of cases the cause of thrombosis remains unknown.
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PMID:[Evaluating the origin of thrombophilia: indications and implementation]. 148 83

We studied the natural inhibitors (NI) of blood coagulation and fibrinolysis in 50 patients with lupus anticoagulant (LA), in order to identify possible alterations of these NI, that could favour thrombotic manifestations. We found no statistically significant difference in antithrombin III, protein C and alpha 2-antiplasmin between controls and patients with LA, irrespective of their clinical manifestations. We found an increase of plasminogen activator inhibitor (PAI, P < 0.001) and a decrease of free protein S (PSf, P < 0.001) and total protein S (PSt, 0.01 < P < 0.05) in the patients with LA when compared with the control group. We found no difference in the levels of NI between patients with thrombosis (n = 19) and without thrombosis (n = 31) nor between patients with (n = 25) or without thrombosis and/or foetal loss (n = 25). In contrast, we observed a decrease of PSf in women with foetal loss (n = 10) as compared with women without foetal loss (n = 22, 0.01 < P < 0.05) and a decrease of PSf when comparing 19 patients with systemic lupus erythematosus (SLE) with 31 patients without SLE (0.01 < P < 0.05). These findings show that the patients with LA had several abnormalities in the NI system, but there was no significant association between levels of PAI, PSf, PSt and a history of thrombosis.
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PMID:Natural inhibitors of blood coagulation and fibrinolysis in patients with lupus anticoagulant. 148 97

Previous studies of patients with thromboembolic disease have revealed an association either with hereditary anticoagulant protein deficiencies or with defects in the fibrinolytic system. To obtain a more comprehensive picture and to investigate which analyses are useful in the evaluation of such patients, we have performed an extensive laboratory investigation in 439 individuals with thromboembolic disease. Anticoagulant protein deficiencies were found in 24 patients. Deficiencies of protein C (n = 10) and protein S (n = 9) were most common followed by deficiencies of antithrombin III (n = 3) and plasminogen (n = 2). Six of the nine protein S deficient patients demonstrated a selective deficiency of free protein S with normal total protein S concentrations. To diagnose protein C and S deficiencies among the 201 patients receiving oral vitamin K antagonists, the concentrations of protein C and S were compared with the mean concentration of several other vitamin K-dependent proteins. One protein C and three protein S deficiencies were identified among the treated patients. The number of protein C deficiencies found in this group was significantly lower than the number found among untreated patients. Although fewer protein S deficiencies were also identified among the treated patients, than in the untreated group, the difference was not statistically significant. The results suggest that protein C deficiencies went undetected in the treated group and that oral anticoagulant therapy should be discontinued before efforts to diagnose protein C deficiency are made. We found no cases with heparin cofactor II deficiency. Lupus anticoagulant was present in 10 patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Thromboembolic disease--critical evaluation of laboratory investigation. 832 78

We examined the relationship between free protein S deficiency and cerebrovascular disease by reviewing the records of all patients with the diagnoses of cerebral thrombosis, cerebral embolism, and cerebral vascular occlusion who were referred for coagulation studies over a 12-month period. We assayed for free protein S antigen, protein C antigen, and antithrombin III and tested for lupus-like anticoagulant and anticardiolipin antibody. Twenty-two of 267 patients (8.2%) admitted with thrombotic strokes were referred for coagulation studies. Free protein S antigen was significantly lower in women than in men (62 +/- 25% versus 88 +/- 24%, p = 0.03; n = 11 in each group). Six women had free protein S antigen levels below the range recorded for a contemporary group of 24 age-matched normal women (17 to 59% versus 70 to 102%, p less than 0.001); four of these women had cerebral arterial thrombosis and two had venous dural sinus thrombosis. The six women were aged 29 to 55 at the time of their first strokes; two had family members with protein S deficiency, and one of these had died of a stroke at age 52. Other abnormalities in this population included a positive test for lupus-like anticoagulant or anticardiolipin in five patients, a modest decrease in protein S in two men, and one patient with an isolated deficiency of antithrombin III. We conclude that protein S deficiency may be an important risk factor for stroke in middle-aged women but this requires confirmation by prospective studies in unselected patients.
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PMID:Protein S deficiency in middle-aged women with stroke. 153 5

Protein C (PC) and protein S (PS) are components of a potent, natural anticoagulant system. A deficiency of one of these two inhibitors is associated with thrombotic events in young people. A significant reduction in functional PS activity has been observed during normal pregnancy, and recurrent fetal loss may occur in women with lupus anticoagulant (LA) inhibitor. We measured functional PS activity and free PS antigen in 16 non pregnant patients with LA inhibitor and in 17 normal women as controls. A significant difference was observed between patients and controls in functional PS activity (65 +/- 23% vs 87 +/- 15%, p = 0.02) but not in free PS antigen (88 +/- 17% vs 93 +/- 17%). Functional PS activity decreased only in six patients (37%). Removal of IgG from plasma reduced the difference in functional PS activity between patients and controls. Immunologic IgG levels did not correlate with anti-phospholipid antibodies (APA) activities, activated partial thromboplastin time/kaolin clotting time (aPTT/KCT) data or functional PS activity.
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PMID:Functional protein S in women with lupus anticoagulant inhibitor. 153 34

Patients with systemic lupus erythematosus (SLE) have an increased risk of thrombosis and this is increased in the presence of antiphospholipid antibodies (APA). These APA are also associated with thrombosis in patients who do not have SLE. We compared haemostatic parameters in SLE patients with and without APA, and also compared patients who had APA but not SLE with healthy normal controls. No relationships between the natural anticoagulants, antithrombin III, heparin cofactor II, protein C and protein S, and the presence of APA were found. In the patients with SLE both tissue plasminogen activator antigen and plasminogen activator inhibitor (PAI) were increased, but these changes were not due to APA which had no effect on fibrinolysis in these patients. In the patients with APA who did not have SLE the fibrinolytic response to venous occlusion was reduced due to raised levels of PAI; similar changes have, however, been reported in some patients with idiopathic thrombosis.
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PMID:The fibrinolytic response to venous occlusion and the natural anticoagulants in patients with antiphospholipid antibodies both with and without systemic lupus erythematosus. 170 91

Thromboembolism remains a major cause of maternal morbidity and mortality. The incidence of thrombosis associated with pregnancy is stated to be around 0.09%1 but is greater in women with familial or acquired thrombophilia. Around 50% of pregnancies in women with antithrombin III deficiency are complicated by thrombosis. Anticoagulation throughout pregnancy and the puerperium is recommended in women with antithrombin III deficiency. Because thrombosis is less common in women with protein C or protein S deficiency less aggressive management may be appropriate during pregnancy but anticoagulation post partum is generally recommended. The most important acquired thrombophilic abnormality is the development of antiphospholipid antibodies ('lupus anticoagulants'). Women with these antibodies may present major problems but no clear guidelines for their management currently exist. The majority of women with a history of thrombosis have no identifiable haemostatic abnormality. Management of pregnancy in these patients depends on individual circumstances.
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PMID:Management of thrombophilia in pregnancy. 178 82

Phospholipids bearing a proportion of anionic species such as phosphatidylserine are necessary to promote the anticoagulant potential of the protein C pathway. Factor Xa (200 or 350 pM) was found to activate protein C in a thrombomodulin-independent reaction requiring only phospholipids in Al(OH)3,-adsorbed plasma resupplemented with physiological concentrations of protein C (70 nM) and protein S (130 nM). All experiments were performed in the presence of an excess of hirudin. The activity of activated protein C was assessed by the survival of factor Va. The optimal phospholipid concentration range was 5 to 25 microM with a proportion of phosphatidylserine of 50% (mol/mol) resulting in a half-life of factor Va of 7.5 min in the absence of protein S and 4.2 min in its presence. Dns-EGR-Xa, an inactive derivative of factor Xa, behaved as an apparent protector of factor Va. When replacing factor Xa, thrombin at 10 nM was not an efficient protein C activator in the absence of purified human placenta thrombomodulin. In the presence of 100 pM activated protein C, factor Va half-life was 2 min in the absence of protein S and 1.1 min in its presence in the above optimal phospholipid concentration range. The presence of protein S allowed reduction of phospholipid requirements. Annexin-V (placental anticoagulant protein-I), a potent phospholipid antagonist, fully protected factor Va from degradation by phospholipid-dependent mechanisms. Factor Va was partially protected in the plasma of a patient having experienced thrombosis associated with lupus-like anticoagulant and anti-phospholipid auto-antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The catalytic role of anionic phospholipids in the activation of protein C by factor Xa and expression of its anticoagulant function in human plasma. 179 56


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