Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012739 (disseminated intravascular coagulation)
 8,673 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Homozygous protein C (PC) deficiency is a rare genetic defect that usually results in fatal thrombotic complications (purpura fulminans and DIC), but it can be successfully managed with oral anticoagulants or PC replacement. The successful use of PC replacement for two individuals is described. The activity and antigen levels of PC in fresh frozen plasma (FFP) and prothrombin complex concentrate (PCC) are also reported. The concentration of PC in FFP is 87 +/- 15 units/dl. PC is present in all PCC analyzed; however, a ten-fold difference between the various brands and/or lots is noted. The PC activity and antigen correlates well with no significant levels of APC. Upon infusion of FFP into two homozygous PC-deficient children, the PC levels obtained were less than or equal to 30 units/dl post-infusion and undetectable after 12-18 hr. With infusions of PCC, plasma levels of PC obtained were 100-145 units/dl and less than 10 units/dl after 48 hr. The percent recovery and half-lives of PC from FFP and PCC were 49.8% and 7.8 hr, and 84% and 7.4 hr, respectively. One infant was treated every 48 hr for 2 years without significant purpura fulminans or DIC complications. The levels of the other PC system components did not change during the infusion of the PC-rich material. Based on this information, a specific replacement protocol has been developed using a PC-rich concentrate. However, several problems may arise with the "less pure" PC-rich concentrates: catheter-tip thrombosis, related large vessel thrombosis and blood-transmitted diseases. With a specific PC concentrate, replacement therapy is a viable alternative for the long-term management/treatment of homozygous PC deficiency.
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PMID:Protein C survival during replacement therapy in homozygous protein C deficiency. 150 96

Protein C (PC) is the central component of a major antithrombotic regulatory system with both anticoagulant and profibrinolytic properties. A deficiency of PC is one of several hereditary abnormalities of haemostatic proteins that have been described in patients with a propensity for thromboembolic complications. Major morbidity is often seen in these patients. The various aspects of hereditary PC deficiency in terms of clinical presentation, genetics, diagnosis and treatment of both homozygous and heterozygous states will be presented. In heterozygous deficiency, the levels of plasma PC are usually between 35% and 65% of normal, whereas the majority of normal individuals have levels between 70% and 130%. PC-deficient patients usually develop venous thrombotic complications between the ages of 15 and 40 years with a high incidence of DVT and pulmonary embolism. The majority of thrombotic lesions appear to develop spontaneously; others are associated with trauma, surgery or pregnancy. Treatment of symptomatic patients is initial heparin therapy followed by coumadin. After multiple thrombotic events, lifelong oral anticoagulant therapy is necessary. The potential complications of treatment are coumadin-induced skin necrosis, heparin-induced thrombocytopenia and bleeding. Homozygous PC deficiency, a rare but fatal hereditary condition, manifests itself with massive DIC and purpura fulminans in the newborn period. Effective treatment for these infants can be instituted with either oral anticoagulant therapy or PC replacement. The heterozygous deficiency of PC is similar to that found in other inherited disorders in that several genetic mechanisms are responsible for the expression of the disease. Both quantitative and qualitative decreases in PC exist, the former being type I deficiency and the latter, type II. The best initial diagnosis of either form involves a clotting (functional) assay while differentiation between the two also requires an antigenic (immunological) assay. Autosomal inheritance with significant variable penetrance is found with profound clinical implications. In summary, PC deficiency is one of a group of inherited disorders termed hereditary thrombotic disease, which may have serious implications for patient morbidity and mortality.
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PMID:Hereditary protein C deficiency: a review of the genetics, clinical presentation, diagnosis and treatment. 210 16

Protein C (PC), a 62,000-molecular weight vitamin K-dependent serine protease zymogen, is a natural anticoagulant that occurs in plasma at 4 mg/L. Activated PC inactivates clotting factors V and VIII and is also profibrinolytic. Activated PC is enhanced in its anticoagulant activity by protein S (PS), another vitamin K-dependent protein. Protein S is found in platelets and endothelial cells as well as in plasma. Inherited PC deficiency and PS deficiency have been associated with venous thrombosis. Both heterozygous PC and PS deficiency appear to be inherited in an autosomal dominant manner in some families. Homozygous PC deficiency presents as neonatal purpura fulminans and results in massive venous thrombosis of the skin and other organs within the first few days of life. Symptomatic heterozygous PC deficiency and PS deficiency have been treated with oral anticoagulants, successfully minimizing recurrence of thrombosis. Coumarin-induced skin necrosis, a rare complication of oral anticoagulant therapy usually seen within three to five days of initiation of therapy, has also been associated with heterozygous PC deficiency. The short half-life of PC (six to eight hours) compared with most of the vitamin K-dependent clotting factors (greater than 30 hours) is the probable reason for this paradoxical response to oral anticoagulants in some PC-deficient patients, since a transient imbalance of procoagulant and anticoagulant factors may exist during initiation of oral anticoagulant therapy. Acquired deficiency of the PC pathway occurs in disseminated intravascular coagulation and possibly other diseases such as those associated with a lupus anticoagulant.
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PMID:Coumarin necrosis, neonatal purpura fulminans, and protein C deficiency. 296 8

Protein C (PC) activities measured by two thrombin-based assays have been compared with those obtained by two assays based on snake venom activation of plasma PC followed by measurement of both the amidolytic and anticoagulant activities of activated PC. This study indicates that snake venom assays gave results similar to those of the thrombin assays in 20 healthy subjects, in 16 patients with DIC and in 15 patients with congenital PC deficiency. There was, however, some degree of misclassification of normals and congenitally-deficient patients, with only the clotting snake venom assay resulting in no misclassifications. In 15 patients stabilized on warfarin treatment and in 17 with liver disease, the clotting snake venom assay gave significantly lower values than the other assays, so that it might prove to be more sensitive than the other assays to these defects.
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PMID:Functional assays of protein C: comparison of two snake-venom assays with two thrombin assays. 321 14

Both anticoagulant and amidolytic activities of protein C (PC) were measured using a snake venom activator in 4 patients with hereditary PC deficiency, 37 with disseminated intravascular coagulation (DIC), and 30 under stabilized warfarin therapy. The results were compared with those obtained by an immunological assay (ELISA). PC levels measured by different functional and immunological assays were very close in patients with hereditary PC deficiency and DIC. In patients under stable oral anticoagulant therapy, there was no detectable difference between amidolytic activity and antigen levels of PC in each patient plasma, whereas a decrease in anticoagulant activity was much more pronounced. These results indicate that the present activity assays measure PC specifically, and that the snake venom activator is capable of activating both carboxylated and hypocarboxylated forms of PC, but only anticoagulant assay can evaluate the physiological PC function in vitamin K-deficient states.
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PMID:Fast functional assay of protein C in whole plasma using a snake venom activator: evaluation in patients with congenital and acquired protein C deficiencies. 341 83

A new practicable and precise functional protein C evaluation test is based on the activation of protein C by a snake venom activator and determination of PC activity by its property to prolong the aPTT in a clotting assay (VK = 1.9% and 4% for intra- and interassay variance respectively). In 40 healthy controls there was a good correlation (r = 0.74) between the functional and immunological (ELISA) evaluation. In 123 patients with both evaluation methods but more pronounced with the measurement of the protein C activity a significant protein C deficiency was found in the patient groups with disseminated solid tumors, inflammatory diseases and myocardial infarction. Besides detection of hereditary PC deficiency Type II (generation of functionally abnormal PC) the functional assay profits by recording PC inhibitor complexes and otherwise dysfunctional PC in DIC. Thus, in patients with hematological neoplasias, only protein C activity was significantly decreases. Decrease of PC activity was more pronounced compared to PC Ag in liver disease indicating synthesis of functionally deficient PC, and in oral anticoagulant treatment due to detection of PIVKA-PC.
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PMID:[Immunologic and functional protein C determination in various internal diseases]. 343 Oct 26

Five functional assays and two immunoassays for protein C (PC) were evaluated in parallel for the same plasma samples collected from healthy subjects, patients with congenital and acquired PC deficiencies or patients with conditions associated with high PC levels. For 7 patients starting warfarin therapy and for 15 patients during stabilized warfarin therapy, there were significant between-assay differences. For these groups immunoassays gave higher values than most functional assays and the latter also gave varied results, probably depending on their respective capacity for recognizing a carboxylated PC. On the other hand, there were no significant between-assay differences nor discrepancies between PC activity and antigen levels for healthy subjects (n = 39), patients with congenital PC deficiency (n = 10), myocardial infarction (n = 25), chronic liver disease (n = 19), disseminated intravascular coagulation (n = 35), in the post-operative period (n = 20) or in women taking oral contraceptives (n = 20). This comparison of PC assays indicates that PC levels measured by different functional or immunological assays are very close in the majority of clinical conditions, but not for patients on oral anticoagulants.
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PMID:Multicenter comparison of five functional and two immunological assays for protein C. 359 79

We report the genetic abnormalities in the protein C genes of a Spanish child with neonatal purpura fulminans and disseminated intravascular coagulation, associated with undetectable protein C levels. Direct sequencing of the nine protein C gene exons and their splice junctions indicated that the proband is a compound heterozygote with two mutant protein C gene alleles, Y124C and Q132X, that do not express protein C in plasma. The Y124C mutation was inherited from the mother and is due to a novel A to G transition at nucleotide 3416, which results in the substitution of cysteine for tyrosine 124, a highly conserved amino acid in EGF-like domains. The paternal inherited mutation (Q132X) is a C to T transition at nucleotide 3439, which replaces glutamine 132 with a Stop codon signal. This mutation, if expressed, should result in the synthesis of a truncated protein of 131 amino acids. Y124C or Q132X are present in the heterozygous state in the asymptomatic parents and siblings of the proband, all of which have half the normal plasma levels of protein C. Q123X has also been identified in families where type I PC deficiency is inherited as a clinically dominant trait. Therefore, the presence of the same mutation in a family showing a clinically recessive pattern of inheritance indicates that other factors, apart from the type of protein C gene mutation, are responsible for the clinical expression of protein C deficiency.
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PMID:Severe type I protein C deficiency in a compound heterozygote for Y124C and Q132X mutations in exon 6 of the PROC gene. 860 97

We report the effects of substitution with a virus-inactivated protein C (PC) concentrate in disseminated intravascular coagulation (DIC) in infants and children with meningococcal sepsis associated with purpura fulminans. It was a prospective open-label study. Eight pediatric and adolescent patients age 0.2 to 18.25 years with DIC associated with severe acquired PC deficiency (range 0.02 to 0.48 IU/mL; median, 0.22 IU/mL) in meningococcal septic shock and purpura fulminans were studied. Replacement therapy was initiated with a virus-inactivated PC concentrate with an initial intravenous bolus of 80 to 120 IU/kg followed by 50 IU/kg up to six times per day as an adjunctive therapeutic regimen to otherwise optimal intensive care treatment. After initial PC administration, plasma PC levels rose to normal ranges and were maintained under PC replacement therapy. Improving or even normalizing global hemostatic parameters were assessed in all patients. Markedly elevated plasminogen activator inhibitor type 1 (PAI-1) levels prior to treatment, reflecting a reduced fibrinolytic potential, decreased rapidly under PC substitution. Concomitantly improving signs of purpura fulminans reflected by decreasing size of skin lesions, demonstrated a restoring microcirculation. Six of the eight patients survived. One patient required limb amputation; two patients died because of multiorgan failure. Both presented with a severely low plasma PC activity of 0.02 IU/mL on admission to the hospital. No adverse effects were observed with the PC concentrate administration. It can be concluded that the administration of PC concentrate had a marked benefit on the deranged coagulation status of patients with purpura fulminans and meningococcal septicemia. Normalization or even partial correction of hemostasis as well as improvement of microcirculation accompanied by improving signs of purpura fulminans were demonstrated in all patients.
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PMID:Replacement therapy with protein C concentrate in infants and adolescents with meningococcal sepsis and purpura fulminans. 1063 75

Protein C (PC) is a vitamin K-dependent plasma protein that is structurally similar to other coagulation factors such as prothrombin and Factor X. PC is converted to its active anticoagulant form by a thrombin-thrombomodulin complex on the surface of capillary endothelial cells. Activated PC (APC) prevents the formation of blood clots by specifically inactivating factors Va and VIIIa in the clotting cascade. Both acquired and hereditary forms of PC deficiency exist, with hereditary further categorised as heterozygous, homozygous as well as doubly heterozygous. Patients suffering from symptomatic heterozygous PC deficiency present with purpura fulminans, venous thrombosis and/or pulmonary embolism. Homozygous PC deficiency is usually associated with the development of severe and often fatal, purpura fulminans and disseminated intravascular coagulation (DIC) during the neonatal period. Various therapeutic options have been described for long-term management of severe heterozygous and homozygous PC deficiencies. For the treatment of heterozygous PC deficiency, oral anticoagulation with a coumarin derivative or heparin therapy remains standard therapy. Homozygous patients may be treated with fresh frozen plasma (FFP) and iv. PC concentrate or coumarin derivatives. Other therapeutic options for the treatment of hereditary PC deficiency include the use of low-molecular weight heparin (LMWH), steroids and liver transplantation. Maintenance of a symptom-free life depends on response to therapy. Patients responding well to treatment can expect normalisation of haemostasis as well as improvement of microcirculation and resolution of purpura fulminans.
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PMID:Clinical management of protein C deficiency. 1133 97


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