Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149871 (deep vein thrombosis)
 12,364 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 30-year-old man presented with an episode of deep vein thrombosis. He was found to have primary antiphospholipid syndrome with anticardiolipin antibodies and protein S deficiency. All other investigations were negative. Three months later, anticardiolipin antibodies were negative and protein S levels were normal. The transient presence of anticardiolipin antibodies and functional protein S deficiency in this patient suggests a new mechanism for the association between anticardiolipin antibodies and venous thrombosis.
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PMID:Transient anticardiolipin antibodies, functional protein S deficiency, and deep vein thrombosis. 182 46

An enzyme-linked immunosorbent assay (ELISA) for measuring total, free and complexed protein S in plasma was developed. To assay free protein S, C4b-binding protein-bound protein S (C4b-BP-PS) was extracted by addition of polyethyleneglycol (PEG) 6000 (5%, final concentration) to plasma samples. Microtiter plates were coated with rabbit anti-human protein S, and bound protein S was detected with labelled anti-protein S antibody. Diluted plasma samples were incubated in the plates overnight at 22 degrees C to permit C4b-BP-PS complexes to dissociate. Mean variation coefficients of 2.1 and 3.2% (intra-assay) and 4.3 and 7.9% (inter-assay) were found for total and free protein S assays, respectively. The ELISA measures free and complexed protein S with equal efficiency as is demonstrated by the fact that the sum of free protein S and C4b-BP-PS complex levels in normal individuals, women in their third trimester of gestation and patients with acute deep vein thrombosis (DVT), equaled the level of total protein S present in the corresponding plasma. Total protein S values obtained with the ELISA, in all groups studied, correlated well with those obtained with a standard electroimmunoassay (EIA) (r = 0.93; n = 40). However, total protein S levels measured by EIA were lower than those assayed by ELISA in pregnant women and in DVT patients. Furthermore, addition of several amounts of purified C4b-BP to NHP, which reduced the recovery of free protein S, did not influence the total protein S values measured by ELISA but slightly decreased the recovery of total protein S measured by EIA. These results indicate the necessity of using assays which accurately and reliably measure the total amount of protein S antigen. After addition of C4b-BP to NHP, the residual functional protein S level was lower than the residual level of free protein S antigen; this lends support to the idea that C4b-BP-PS complex inhibits the activated protein C cofactor activity of protein S.
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PMID:Determination of total, free and complexed protein S in plasma by ELISA, and comparison with a standard electroimmunoassay. 183 53

Thromboembolic events occur with a frequency of 3-5% in children with nephrotic syndrome (NS). Although numerous abnormalities in all phases of coagulation have been described in NS, the pathogenesis of clotting abnormalities remains poorly understood in this group of patients. We describe a child with long-standing NS in whom a severe deep venous thrombosis and pulmonary embolism secondary to acquired protein S deficiency and a strong lupus-type circulating anticoagulant developed. In addition, this patient had a markedly decreased plasma level of C4b binding protein. Although acquired protein S deficiency has been described in various clinical disorders including NS, our patient is unusual in having C4bBP deficiency, and his is the only reported pediatric case of NS complicated by thromboembolism in which a circulating anticoagulant has been implicated, to our knowledge.
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PMID:Deep venous thrombosis in a child with nephrotic syndrome associated with a circulating anticoagulant and acquired protein S deficiency. 183 4

We have identified an inhibitor of the protein C anticoagulant pathway in the plasma of a patient with systemic lupus erythematosus and a history of recurrent deep vein thrombosis, fetal wastage, and seizures. The patient's plasma contained anticardiolipin antibodies as well as a weak lupus anticoagulant. Examination of this patient's plasma revealed normal levels of protein C and protein S antigen, normal levels of functional protein C, as well as essentially normal levels of every blood coagulation factor. In a modified prothrombin time assay, the activated protein C-mediated prolongation of the clotting time observed in normal plasma was not observed in this patient's plasma. Gel permeation chromatography of the patient's plasma revealed that the inhibitory material was a high molecular weight protein that coeluted with the IgM peak. The inhibitor did not appear to circulate as a complex with protein C, since the inhibitor could easily be separated from protein C during fractionation procedures, and did not interfere with the activation of protein C in plasma as assessed by a functional amidolytic assay. Our findings suggest that the recurrent thrombotic episodes observed in this patient may have occurred as a result of the patient's antiphospholipid antibody neutralizing specific phospholipids essential for the full expression of the anticoagulant activity of activated protein C.
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PMID:Impairment of the protein C anticoagulant pathway in a patient with systemic lupus erythematosus, anticardiolipin antibodies and thrombosis. 210 91

Lipodermatosclerosis of the lower extremity, with or without ulceration, is a common manifestation of severe venous disease and the result of sustained venous hypertension. The latter is generally a sequela of deep vein thrombosis. Factors that enhance clot formation or impair fibrinolysis contribute to the pathogenesis of venous disease. It is already established that faulty fibrinolysis may play a pathogenic role in patients with venous disease. We examined the possibility that patients with venous disease have abnormally low plasma levels of proteins C and S, two proteins whose deficiencies have been reported to cause an increased frequency of thromboembolic disease. Using immunologic and functional assays for plasma proteins C and S, we found that 4 (21%) of 19 patients with lipodermatosclerosis and leg ulcers had abnormally low levels of protein C or protein S. One of 7 patients with lipodermatosclerosis without ulceration had a profoundly depressed level of protein C and a history of cerebral stroke at a young age. Plasma levels of protein C were normal in five patients with arterial insufficiency severe enough to cause leg ulceration. We conclude that abnormally low plasma levels of proteins C and S may be found in patients with lipodermatosclerosis and venous ulceration. As with the abnormally low fibrinolytic activity in these patients, our findings indicate a possible propensity for increased thrombotic disease.
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PMID:Protein C and protein S plasma levels in patients with lipodermatosclerosis and venous ulceration. 203 43

Patients with primary hypercoagulopathies often present with recurrent, spontaneous deep venous thrombosis and pulmonary embolism. An adolescent eventually diagnosed with protein S deficiency presented with unilateral deep venous thrombosis documented ultrasonographically. Scintigraphic studies showed no evidence of pulmonary embolism but revealed a complete absence of deep venous flow in both lower extremities, the pelvis, and the abdomen. Subsequent ultrasonography and CT scanning documented this marked thrombotic extension. Radionuclide scintigraphy may play an important role in the serial evaluation of primary hypercoagulable states, particularly when pulmonary scintigraphy is combined with bilateral, lower extremity venography.
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PMID:Bilateral deep venous thrombosis in protein S deficiency. Detection by radionuclide venography. 214 11

Inherited deficiencies of protein S, an inhibitor of the coagulation system, are now recognized as occurring at least twice as frequently as antithrombin III deficiency in patients with venous thrombosis. Protein S is present in plasma in a complexed form, which is inactive, and in a free or functional form. Free protein S combines with activated protein C to inhibit factors V and VIII. This report describes the evaluation of a family with recurrent deep venous thrombosis and superficial thrombophlebitis. Levels of antithrombin III and protein C as well as plasminogen were normal. The levels of total protein S, which includes the value for the free and complexed forms of protein S, were also normal. However, the free protein S levels were greatly reduced in all symptomatic members who were studied. This report illustrates the importance of obtaining measurement of free protein S levels in patients who are suspected of having inherited venous thrombotic disorders.
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PMID:Free protein S deficiency in a family with venous thrombosis. 214 6

Subjects with congenital deficiency of protein S, a natural anticoagulant which serves as a co-factor for the antithrombotic activity of activated protein C, are at risk of thrombosis. We describe a family in which deep vein thrombosis-occurring during pregnancy in three members with abnormally low protein S activity - was the only manifestation of congenital heterozygous protein S deficiency. Early diagnosis and active treatment of protein S deficiency should be pursued in any woman with a family history of thrombosis, who is planning pregnancy.
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PMID:Familial protein S deficiency presenting as deep vein thrombosis occurring during pregnancy. 214 88

The protein C inhibitor (PCI) concentration and other parameters of the protein C pathway were studied in 19 patients with symptomatic acute deep vein thrombosis before and during the first 5 days of heparin treatment. The mean levels of PCI antigen and activity decreased rapidly and significantly during the first day of heparin therapy from 83 and 84% to 60 and 59% of the pooled normal human plasma (p less than 0.01), respectively, and to 56 and 54% after 5 days of treatment (p less than 0.01). In contrast, antithrombin III decreased progressively 25% during 5 days of heparin treatment. Protein C antigen and activity and total protein S remained unchanged during heparin treatment. Free protein S was decreased before heparin treatment (83%, p less than 0.05) and increased to normal values after 5 days of treatment. C4b-binding protein was significantly increased before and during heparin treatment (p less than 0.01). Activated protein C (APC) complexed to its two major plasma inhibitors, PCI and alpha 1-antitrypsin (alpha 1AT) were measured by specific ELISA's. Before treatment, 18 of the 19 patients studied had increased levels of APC:alpha 1AT complexes with a mean value of 27 +/- 22 ng/ml (range, 6-86 ng/ml) compared to normal values (8 +/- 2 ng/ml) and 12 of the patients also had detectable APC:PCI complex levels with a mean value of 11 +/- 17 ng/ml (range, 5-68 ng/ml). Both APC:inhibitor complexes decreased significantly during heparin treatment.
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PMID:Protein C inhibitor and other components of the protein C pathway in patients with acute deep vein thrombosis during heparin treatment. 216 56

The pre-surgery identification of patients at risk for the development of post-operative venous thromboembolism has not yet been achieved. It is a well recognized fact that major surgery without prophylaxis encompasses a high risk for thrombosis, in particular orthopaedic operations (hip/knee surgery approximately 50%) and abdominal surgery (approximately 20%). Other well-defined risk factors, though rarely occurring, are deficiencies of the major inhibitors of blood coagulation (i.e. protein C, protein S and antithrombin III). Less well-defined risk factors are a history of previous thrombosis, obesity, varicosis, cancer etc. In an attempt to identify patients at risk for thrombosis prior to surgery, several investigators have developed complicated risk predictors, i.e. formulae comprising combinations of coagulation test results and physical characteristics such as body weight. However, the clinical usefulness has only been demonstrated in two small studies evaluating gynaecological surgery patients. These prognostic indices have not, however, found general acceptance and are not used routinely. The importance of all these risk factors for patient management with regard to thrombosis prevention is relatively small. Irrespective of the absence or presence of identified risk factors, currently the majority of patients will receive some formal thrombosis prophylaxis. The major problem at present is the development of proximal vein thrombosis despite the best possible thrombosis prophylaxis (approximately 10% after hip surgery). Identification of these patients pre-operatively or in an early stage in the post-operative phase by single screening tests should be a major research issue. Furthermore, the development of a prophylactic regimen which eliminates proximal deep vein thrombosis is still desperately needed.
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PMID:Pre-surgical identification of the patient at risk for developing venous thromboembolism post-operatively. 228 76


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