Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cause of the thrombotic tendency in nephrotic patients is unknown. Recent reports of thrombotic complications in patients with deficiencies of protein C or protein S (natural inhibitors of coagulation) have raised the possibility that decreased levels of these proteins may play a role in the hypercoagulable state of nephrotic patients. We measured the levels of protein C, total protein S, and free protein S antigens in 42 patients (21 nephrotic and 21 non-nephrotic) with one of four types of glomerular pathology: diabetic nephropathy (DM), focal glomerular sclerosis (FGS), membranous glomerulonephritis (MGN), and chronic renal failure due to hypertension (CRF). Protein C and total protein S antigen levels were significantly higher in FGS and MGN than they were in DM or CRF. Free protein S levels were lower in DM than they were in MGN. Protein C, total protein S, and free protein S levels did not significantly correlate with either serum albumin or degree of proteinuria. The mean levels of the three proteins did not differ between nephrotic and non-nephrotic patients. Free protein S and protein C were, however, significantly correlated (P less than .005 and P less than .002, respectively) with the type of glomerular pathology, independent of differences in age, sex, serum albumin, or degree of proteinuria. These data suggest that abnormalities of free protein S and protein C are related to the nature of the underlying renal disease, rather than to the degree of proteinuria.
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PMID:Protein S and C antigen levels in proteinuric patients: dependence on type of glomerular pathology. 252 34

We report a study of 61 cases of retinal vein occlusion, followed for 3-10 years. The oedematous form only were studied; 39 were branch vein occlusion (BVO) and 22 central retinal vein occlusion (CRVO). Of the CRVO's 5 were female, 17 were male, ages ranged from 5 to 75 years, averaging 58 years of the BVO's there were 19 females and 20 males with ages ranging from 27 to 79 years, averaging 61 years. High blood pressure and atherosclerosis were the most frequent causes. High intraocular pressures were mostly associated with CRVO (25%). Study of serum lipids and blood coagulation are most useful in CRVO in young patients. Platelet agreggation anomalies, protein C deficiency were seen in some cases. Visual prognosis is relatively good; bilateralisation was seen in 5% of BVO and in 9% of CRVO. Visual acuity better than 20/200 was observed in 87% of BVO and in 75% of CRVO.
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PMID:[Long-term follow-up and etiologic factors in edematous forms of central retinal vein obstruction]. 262 8

Protein C, protein S and antithrombin III were evaluated in normal pregnancy, severe preeclampsia and chronic hypertension with superimposed severe preeclampsia. The same study was performed on a group of 10 normal women using oral contraceptives. In normal pregnancy a significant decrease in the level of free and total PS was observed in the 2nd trimester of pregnancy and was sustained throughout the remaining months. No significant changes in the levels of protein C and antithrombin III were observed during normal pregnancy. In preeclamptic states a significant decrease in protein C was observed. It was more evident in severe preeclampsia when compared with the normal pregnancy group at similar gestational age. No statistically significant differences in protein S were found when the normal and pathological groups were compared. Antithrombin III decreased only slightly in the severe preeclamptic group. The decrease in protein C and antithrombin III levels in severe preeclampsia could be related with the microthrombotic state that these patients may present. However, the role played by protein S, which decreases during normal pregnancy and in preeclampsia, is not clear. A decrease in the level of total protein S was observed in the group of women using oral contraceptives. No significant changes in protein C and antithrombin III levels were observed in this group.
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PMID:Physiological coagulation inhibitors (protein S, protein C and antithrombin III) in severe preeclamptic states and in users of oral contraceptives. 296 52

An infant with severe homozygous protein C deficiency was brought to medical attention because of purpura fulminans and severe bilateral vitreous hemorrhages in the neonatal period. Infusions of fresh frozen plasma were given for 8 months. On two occasions, attempts to decrease the frequency of fresh frozen plasma infusions to less than twice a day led to episodes of microangiopathic hemolysis, fibrinolysis, and acute renal failure. Infarction of skin and subcutaneous tissues did not recur. Both episodes were controlled after reinstitution of fresh frozen plasma. Complications of therapy with fresh frozen plasma included hyperproteinemia and hypertension. Warfarin therapy was instituted when the baby was 8 months of age, followed by a gradual withdrawal of fresh frozen plasma therapy. The dose of warfarin required to maintain the prothrombin time in a range of 1.8 to 2.2 times normal varied considerably during short periods, a phenomenon that may have been due to several factors: hypercatabolism of the drug with prolonged administration, abnormality of liver function, variation in levels of serum albumin, fluctuations in drug dosage secondary to oral administration, and variations in dietary vitamin K. Protein C determinations by immunologic and functional assays consistently showed detectable but reduced protein C antigen levels with undetectable activity levels, suggesting that a dysproteinemia rather than a deficiency of synthesis is responsible for the child's coagulopathy.
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PMID:Homozygous protein C deficiency: observations on the nature of the molecular abnormality and the effectiveness of warfarin therapy. 334 Apr 76

To assess hemostatic risk factors for sudden death in patients with stable angina, 323 consecutive patients were recruited prospectively. Patients with clinical heart failure or recent myocardial infarction were excluded. The following clinical variables were recorded: age, gender, smoking habits, hypertension, previous myocardial infarction, left ventricular hypertrophy, and severe ventricular arrhythmia. Angiographic variables included coronary extent, assessed from Jenkins' and mean atherosclerotic scores, and left ventricular ejection fraction. Lipid variables included total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and apolipoproteins A-I and B. Hemostatic factors included fibrinogen, fibrinopeptide A, antithrombin III, factor VIII antigen, factor VIII coagulant, protein C, plasminogen, alpha 2 antiplasmin, euglobulin clot lysis time, tissue plasminogen activator before and after venous occlusion, and plasminogen activator inhibitor. There were 34 deaths, 19 of which were sudden during the follow-up period (60 +/- 17 months). The association between each variable and the risk of sudden death was assessed by calculating the relative risk with the Cox univariate model. All significant predictors from the univariate analysis were then incorporated in a Cox multivariate model to select the independent predictors of sudden death. The independent predictors of sudden death were left ventricular hypertrophy (p < 0.04), lower left ventricular ejection fraction (p < 0.04), and shorter euglobulin clot lysis time after venous occlusion (p < 0.02), whereas fibrinogen (p < 0.07) and Jenkins' score (p < 0.08) were borderline. Determination of hemostatic variables, especially those pertaining to dynamic fibrinolysis, may thus be of value in assessing risk of sudden death.
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PMID:Predictive value of hemostatic factors for sudden death in patients with stable angina pectoris. 761 16

The recent analysis of blood components has revealed that retinochoroidal circulation may be disturbed in patients with abnormalities of blood components. These blood abnormalities include iron deficiency anemia with or without thrombocytosis, dysplasminogenia, von Willebrand's disease, protein S deficiency, protein C deficiency, and abnormal platelet function. The ophthalmoscopic findings in these disorders include retinal vein occlusion, retinal artery occlusion, choroidal circulatory disturbance, and vitreoretinal hemorrhage. The incidence of blood component abnormalities is high in young patients who rarely have systemic hypertension or arterial sclerosis. We review these blood disorders and emphasize the importance of blood analysis in the patients with retinochoroidal circulatory disturbances.
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PMID:[Retinochoroidal circulatory disturbances and blood component abnormalities]. 773 14

Recent cohort and case control studies of low-dose combined oral contraceptives (COCs) containing the new generation of progestogens have allowed classification of adverse effects into those which are rare but serious and should be considered risks and those which are more frequent but are less of a threat to health. Low-dose COCs continue to affect coagulation in a complex way, but the risk is less than with the older preparations, and it can be minimized by screening women for a personal or familial history of early or unusual thrombosis and for levels of protein C, S, and antithrombin III. Women with true migraine with focal signs should also avoid using COCs. The relative risk of myocardial infarction (MI) may increase from 4:1 in women with one risk factor (age, smoking, hypertension, hyperlipidemia, and diabetes) to 20:1 with two risk factors and 128:1 with three or more risk factors. In the absence of all risk factors, a recent study indicated that the relative risk of MI with COC use was 1.9 for current and past use. COC use also causes a slight increase in hypertension in most women, especially those who are older or have a family history of hypertension. While the COC can affect carbohydrate and lipid metabolism, the new generation of progestogens has reduced these effects. The COC may accelerate presentation of gallbladder disease in predisposed women. The COC protects against benign breast disease but may increase the risk of breast cancer and cervical cancer slightly. There is a strong link between hepatocellular adenoma and COC use, but the incidence is low. Return to fertility after use has not been a problem. Both estrogenic adverse effects (nausea, dizziness, irritability, weight gain, bloating) and progestogenic adverse effects (vaginal dryness, acne, hirsutism, weight gain, depression, loss of libido) can occur in 50% of women, but these generally disappear after a few months of use. In conclusion, the low-dose, third generation COCs are associated with minimal risks in the absence of other risk factors and have many beneficial effects such as the prevention of ovarian and endometrial cancer; a decrease in pelvic inflammatory disease and ectopic pregnancies; and protection from anemia, primary dysmenorrhea, functional ovarian cysts, and benign breast disease as well as from the morbidity and mortality associated with pregnancy.
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PMID:The combined oral contraceptive. Risks and adverse effects in perspective. 776 40

In eight patients with Legg-Perthes disease, we assessed the etiologic roles of thrombophilia caused by protein C and protein S deficiency and hypofibrinolysis mediated by low levels of tissue plasminogen activator activity. We speculated that thrombosis or hypofibrinolysis were common causes of Legg-Perthes disease. Three of the eight patients had protein C deficiency; they came from kindreds with previously undiagnosed protein C deficiency. In one of these three kindreds there were six protein C-deficient family members (beyond the proband child), four of whom had thrombotic events as adults. One of the eight patients had protein S deficiency, as did his brother who had sustained mesenteric vein thrombosis at age 43. One of the eight patients who had normal proteins C, S, and antithrombin III had hypofibrinolysis, failing to elevate tissue plasminogen activator activity after 10 min of venous occlusion at 100 mm Hg. Plasminogen activator inhibitor, alpha 2-antiplasmin, and fibrinogen values were normal in all eight patients. Beyond their Legg-Perthes disease, none of the eight patients had evidence for venous thrombosis. Of the eight patients, four had thrombophilia and one had hypofibrinolysis, disorders that we believe contributed to thrombotic venous occlusion of the femur with subsequent venous hypertension and bone death that characterize Legg-Perthes disease.
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PMID:Protein C and S deficiency, thrombophilia, and hypofibrinolysis: pathophysiologic causes of Legg-Perthes disease. 804 73

The aim of the present study was to investigate the occurrence of changes in the plasma levels of vasoactive prostanoids and inhibitors of blood coagulation in normal pregnancy and in cases of pregnancy induced hypertension. Levels of the coagulation inhibitors antithrombin III, protein C, Protein S as well as the prostaglandin metabolites thromboxane B2 and 6-oxo-prostaglandin F1 alpha were measured between 13 and 37 weeks gestation in 36 primigravidae. In 8 of the examined patients persistently raised blood pressure values of 140/90 and above were measured after 20 weeks of gestation. Our results indicated that an imbalance of vasoactive prostanoids may precede the appearance of clinical symptoms of PIH. The determination of coagulation factors before blood pressure is elevated has no predictive value regarding the later development of PIH. The reduced levels of protein C associated with our PIH group are considered to be the result of an activated coagulation followed by consumption of clotting factors. Reduced measured levels of protein S in normotensive as well as hypertensive pregnancies offer an explanation for the increased risk of thromboembolic disease. This increased susceptibility to thromboembolic disorders is further enhanced by the altered balance between the platelet aggregator and vasoconstrictor thromboxane A2 and its antagonist prostacyclin.
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PMID:[Vasoactive prostanoids and inhibitors of blood coagulation in pregnancy-induced hypertension]. 804 87

The first generation high-dose ( 80 mcg estrogen) oral contraceptives (OCs) were associated with an increased risk of deep venous thrombosis (DVT). So manufacturers removed the high-dose OCs and first replaced them with OCs with 50 mcg estrogen, resulting in a lower incidence of thromboembolic events (40 vs. 20/100,000 users). When they introduced an even lower dose OC (30 mcg estrogen), the incidence fell further (about 8/100,000 users). Yet, women using the lowest-dose OCs still have DVT more often than do control women. Life-style, age, and smoking may be confounding factors, however. It is not clear whether loss of endogenous ovarian steroid production or the effects of the orally administered contraceptive steroids cause significant changes in hemostatic factors (antithrombin III, protein S, protein C, plasminogen, tissue-type plasminogen activator, plasminogen activator inhibitor 1, histidine-rich glycoprotein, and VII, VIII, X, XII coagulation factors) during OC use. These changes tend to be within normal ranges. There is some doubt that these changes have any clinical significance. In nonsmokers, increased activity of anticoagulant factors and fibrinolytic factors counteract the effects on coagulation factors. Progestin-only OCs appear to affect hemostasis but have not increased the risk of thrombosis. There are considerable differences between people in pharmacokinetics and pharmacodynamics of contraceptive steroids. These differences may account for the increased risk of thromboembolic events in some people. Further research should identify methods of individualizing the dose of contraceptive steroids for a single patient. It should also explore the close interrelationship between hemostasis and lipid metabolism, carbohydrate metabolism, and hypertension in the development of cardiovascular disease in OC users. Providers should discourage women with a past history of DVT from using hormonal contraception.
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PMID:Coagulation and anticoagulation effects of contraceptive steroids. 817 1


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