Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The discovery of the resistance to activated protein C (APCR) has provoked a new insight into the etiopathogenesis of venous and arterial thrombosis. APCR is determined in 95% genetically by point mutation in the gene for factor V resulting in substitution of arginine in the position 506 by glutamine. This change makes the activated form of factor V (factor Va) resistant to the cleavage by protein C in the place, where the cleavage takes place most quickly under normal conditions. The mutant factor V is known as factor V Leiden. Factor V Leiden preserves its procoagulation activity for a longer period, resulting thus into thrombophilia with all its negative consequences. The inherited deficiencies of antithrombin III, protein C and protein S occur in 10% of patients suffering from venous thrombosis, whereas factor V Leiden is present in as many as 20 to 60%. Thus, it seems that factor V Leiden is the most important inherited risk factor of venous thrombosis. The results of several trials did not indicate the participation of APCR in the development of myocardial infarction. On the other hand, APCR seems to be a risk factor of cerebrovascular accidents, especially of stroke and transitory brain ischemia. Factor V Leiden is an important risk factor of abortions, especially those occurring in the second trimester of pregnancy. According to recent results, factor V Leiden is considered to play a role in the pathogenesis of venous and arterial thromboses in children. The significant risk potential of factor V Leiden with respect to venous thrombosis development and relatively simple diagnosis of this mutation predispose the investigation of this disorder to become the screening method in indicated groups of patients. The investigation of APCR is recommended in all patients with either first or reoccurring attacks of venous thrombosis or thromboembolism, in patients with positive family history of thrombosis and thromboembolism and in women with repeated abortions, particularly in the second trimester of pregnancy. The investigation of APCR in selected groups of patients and early prophylactic anticoagulation therapy may be important in thrombosis prevention in situations with an increased thrombotic potential. (Tab. 1, Ref. 78.)
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PMID:Resistance to activated protein C--frequent etiologic factor for venous thrombosis. 1172 76

The role of plasma-phase risk factors for stroke in the pediatric age group is presently unclear due to the lack of sufficiently large prospective studies, and due to the fact that these risk factors do not apply uniformly to newborns, children with sickle cell disease, and older children. Available evidence indicates that factor V Leiden, prothrombin 20210A, and lipoprotein (a) are all important in the pathogenesis of arterial ischemic stroke in older children, but the role of other plasma-phase risk factors remains uncertain. The contribution of these risk factors to newborn stroke and the stroke of children with sickle cell disease is similarly unclear, likely because the ischemia in affected children is predominantly due to nonhematologic perinatal events and erythrocyte adhesion to endothelium with obstruction of flow in the cerebral microcirculation, respectively. Evaluation of childhood stroke should, in our view, always be performed from the standpoint of the presenting clinical symptoms, diagnostic imaging, and determination of plasma-phase risk factors. Therapeutic anticoagulation and use of antiplatelet agents at present focus on the older child.
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PMID:Arterial ischemic stroke in childhood: the role of plasma-phase risk factors. 1192 26

Factor V Leiden mutation has emerged as one of the leading abnormalities in inherited blood coagulation disorders, resulting in a markedly increased risk for deep leg vein thrombosis. A 24-year-old woman presented with acute onset of critical ischemia of her left thumb and index finger. Intraarterial angiography revealed an embolus in the distal radial artery and a thrombotic occlusion of the digital artery of the thumb and index finger. Immediate therapy encompassed a selective surgical embolectomy of the distal radial artery followed by a local intraarterial lysis that was continued for 3 days. Additionally, therapeutic anticoagulation and vasodilating drugs (prostaglandin E) were administered. Within 2 days, capillary refill reappeared and the initial loss of sensory function at the tip of the thumb and index finger diminished. A screening test for thrombophilic disorders led to the diagnosis of a heterozygous mutation of factor V (Leiden mutation). Arterial thromboembolic events of factor V Leiden mutation are rare and have to date been described only in the supraaortic and coronary circulation. Therefore, the arterial embolism to the left hand presented in this report constitutes a rarity that could be successfully salvaged by the combined use of a vascular surgical procedure and intensified medical management.
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PMID:Arterial embolism to the upper extremity in a patient with factor V Leiden mutation (APC resistance)--a case report and review of the literature. 1259 6

Leiden Factor V mutation, associated with resistance to activated protein C, is a prothrombotic state found in 20% of the patients with a first episode of deep-vein thrombosis. We report the case of a 30-Year-old woman with a history of intermittent abdominal pain who developed small bowel infarction requiring extensive small bowel resection. Biological search for prothrombotic disorder showed resistance to activated protein C due to homozygosity for the factor V Leiden mutation. Long-term anticoagulant therapy was initiated. Unexplained abdominal pain may be due to venous mesenteric ischemia, which can be associated with factor V Leiden mutation.
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PMID:[Chronic abdominal pain due to bowel ischemia in a patient with Leiden factor V mutation]. 1509 81

Catastrophic antiphospholipid syndrome (CAPS) is a severe and rare variant of antiphospholipid syndrome (APS) characterized by acute multiorgan failure due to small vessel thrombi in patients with positive antiphospholipid antibodies. We report a fatal case of catastrophic antiphospholipid syndrome in a young woman with a history of polymyositis and Hodgkin lymphoma. The patient was admitted to hospital because of severe foot pain following several weeks of skin ulcerations. Doppler ultrasonography showed evidence of arterial ischemia of the both lower extremities. Despite anticoagulation, immunosuppression, plasmapheresis and antibiotic therapy, she developed cutaneous gangrene, retroperitoneal hematoma, ileus, and acute respiratory and renal failure that resulted in death. Autopsy showed multifocal vascular injury and microthrombi with associated hemorrhages and infarcts in multiple organs. The patient had normal levels of functional protein C and protein S and a normal level of plasma homocysteine. Tests for common thromophilic gene mutations including prothrombin 20210, factor V Leiden 1691, and methylene tetrahydrofolate reductase 677 were negative. To our knowledge, this is the first CAPS patient with molecular studies for genetic prothrombotic mutations. Our report showed that there was no association between the development of CAPS and inherited thromophilia.
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PMID:Catastrophic antiphospholipid syndrome: a rare cause of disseminated microvascular thrombotic injury - a case report with pathological and molecular correlative studies. 1574 23

Thrombosis of the portal-mesenteric axis is an infrequent cause of intestinal ischemia or infarction. In addition to the multiple acquired factors that contribute to the development of this entity, hereditary risk factors, especially the factor V Leiden mutation and the G20210A mutation of the prothrombin gene, have been implicated. The G20210A mutation of the prothrombin gene is found in up to 40% of patients with splenic-portal-mesenteric thrombosis. The present case illustrates the unusual and nonspecific presentation of this mutation in the form of diarrhea and images of thrombosis of the superior mesenteric-portal vein and cavernous transformation of the portal vein. Delayed diagnosis is highly frequent since the clinical signs, laboratory investigations and radiological tests do not suggest the diagnosis. The patient received anticoagulant treatment and showed clinical improvement with complete portal-mesenteric recanalization. Currently the diagnostic technique of choice is magnetic resonance angiography or computerized tomography angiography and treatment consists of indefinite anticoagulation. This case illustrates that an unusual or atypical localization of venous thrombosis may be a manifestation of thrombophilia, emphasizing the importance of genetic screening in these cases.
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PMID:[Portal-splenic-mesenteric venous thrombosis secondary to a mutation of the prothrombin gene]. 1598 14

Activated C protein resistance is a common coagulation defect caused by factor V Leiden mutation and is associated with an augmented risk of predominantly venous thrombosis. Augmented tendency to arterial thrombosis is sporadically reported. This case report describes femoropopliteal thrombosis in a young patient with heterozygous V Leiden factor mutation. Progressive thrombotic occlusion required amputation of the forefoot which resulted in stump dehiscence. Poor blood supply to the perilesional substrate delayed wound healing. An optimal though not yet definitive result was achieved after months of accurate medication. The criticality of lower limb ischemia in an otherwise healthy young patient underscores the grave impact this condition can have on the patient's quality of life and on health care costs.
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PMID:[Femoropopliteal arterial thrombosis in a young patient with heterozygous V Leiden factor mutation. Case report]. 1737 84

The ischemia in children affected by perinatal stroke has long been thought to be driven by nonhematologic maternal and perinatal events. New information from clinical studies, however, tells us that plasma-phase risk factors, such as factor V Leiden, elevated lipoprotein (a), and mutations in MTHFR, may be important in the pathogenesis of perinatal stroke, if not always in the risk of recurrence. With regard to stroke recurrence, this risk is only about 2% according to the largest follow-up study to date, and certainly less than 5%. Nonetheless, when strokes do recur, they tend to be associated with the presence of plasma-phase risk factors in the affected child, suggesting that a small percentage of children with a first perinatal stroke may benefit from anticoagulation therapy, both to prevent stroke recurrence as well as occurence of a second, non-CNS thrombotic event. Counselling of parents with regard to subsequent pregnancies should always include medical management of systemic maternal disorders, such as diabetes, persistently elevated antiphospholipid antibodies, and inherited maternal hypercoagulability states.
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PMID:Prothrombotic risk factors in the evaluation and management of perinatal stroke. 1782 81

Pre-eclampsia is a pregnancy-associated disease of the second part of the pregnancy, occurring mainly after 20th weeks gestation. The prevalence of hypertension in pregnancy is between 5 to 11% and affects mainly women under 20 years of age. An inadequate invasion of trophoblasts with consequential placental ischemia as a result of insufficiently dilated uterine spiral arteries is thought to be an initial cause in the pathogenesis of pre-eclampsia. The clinical symptoms of pre-eclampsia, such as loss of intravascular volume and edema, are caused by generalized endothelial dysfunction. These symptoms are potentiated by hypertension and reduced colloid osmotic pressure in the plama. The organs being affected by pre-eclampsia are those of the vascular-, hepatic-, renal-, cerebral- and coagulatory systems. The prognosis is much more severe when pre-eclampsia develops very early in the pregnancy. The symptoms include elevated blood pressure (over 140 mmHg systolic, 90 mmHg diastolic) combined with proteinuria. Frequent symptoms are hyperreflexia and edema. The etiology of pre-eclampsia has not been clearly defined. Risk factors/triggers for the development of pre-eclampsia can include chronic hypertension, advanced maternal age at first pregnancy (over 35 y), nephropathy, thrombophilia (heterozygous factor V Leiden mutation, antiphospholipid syndrome, heterozygous prothrombin mutation and homozygous MTHFR), multiple gestation and prior pregnancy with preeclampsia. The incidence of preeclampsia is higher in nulliparous than multiparous women. In many countries pre-eclampsia is still most frequent cause of maternal perinatal mortality. HELLP-Syndrome (haemolysis-elevated liver enzyme- low platelets) is a severe progressive course of this disease. Eclampsia, characterized by generalized tonic-clonic convulsion, is the most dangerous complication of pre-eclampsia, and may develop before or after delivery. This form of pre-eclampsia is associated with higher maternal and fetal mortality. Constant maternal hypertension potentially alter vascular integrity of the placenta with further consequences in fetal blood supply leading to growth restriction or zero growth and subsequently resulting in low birth weight or fetal death. The sooner the disease is detected and confirmed, the better the maternal and fetal prognoses are. This is the reason why it is major importance, together with the employment of preventive measures, to identify patients with risk factors with pre-eclampsia though an adequate screening method, thereby detecting the disease earlier and ensuring better pregnancy outcomes for both mother and child.
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PMID:[Pre-eclampsia screening in first and second trimester]. 1897 29

Neonatal extremity gangrene is rare, even rarer are those born with evidence of intrauterine vascular occlusion. Intrauterine limb ischemia has been attributed to several etiological factors which include thromboembolic disease occluding the arteries of the affected limb or compression of the limb during intrauterine life. In this report, we present a case of brachioradial arterial thrombosis associated with mild homocysteinemia and double heterozygosity of methylenetetrahydrofolate reductase 677C-T and factor V Leiden gene mutations. We suggest investigating the neonates and their mothers for possible genetic prothrombotic risk factors when they present with intrauterine thrombosis as this issue is important for management and counseling.
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PMID:Intrauterine upper limb ischemia associated with fetal thrombophilia: a case report and review of the literature. 2050 86


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