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Heterozygous protein C deficiency occurs in 0.14–0.50% of the general population. Based on an estimated carrier rate of 0.2%, a homozygous or compound heterozygous protein C deficiency incidence of 1 per 4 million births could be predicted, although far fewer living patients have been identified. This low prevalence of patients with severe genetic protein C deficiency may be explained by excessive fetal demise, early postnatal deaths before diagnosis, heterogeneity in the cause of low concentrations of protein C among healthy individuals and under-reporting.
The incidence of protein C deficiency in individuals who present with clinical symptoms has been reported to be estimated at 1 in 20,000.
Purpura fulminans is rare and most commonly occurs in babies and small children but can also be a rare manifestation in adults when it is associated with severe infections. For example, Meningococcal septicaemia is complicated by purpura fulminans in 10–20% of cases among children. Purpura fulminans associated with congenital (inherited) protein C deficiency occurs in 1:500,000–1,000,000 live births.
Haemophilia A occurs in approximately 1 in 5,000 males, while the incidence of haemophilia B is 1 in 30,000 in male population, of these, 85% have haemophilia A and 15% have hemophilia B.
In terms of the cause of protein S deficiency it can be in "inherited" via autosomal dominance.A mutation in the PROS1 gene triggers the condition. The cytogenetic location of the gene in question is chromosome 3, specifically 3q11.1 Protein S deficiency can also be "acquired" due to vitamin K deficiency, treatment with warfarin, liver disease, and acute thrombosis (antiphospholipid antibodies may also be a cause as well)
Two Dutch studies have followed hemophilia patients for a number of years. Both studies found that viral infections were common in hemophiliacs due to the frequent blood transfusions which put them at risk of getting blood borne infections such as HIV and hepatitis C. In the latest study which followed patients from 1992 to 2001, the male life expectancy was 59 years. If cases with known viral infections were excluded, the life expectancy was 72, close to that of the general population. 26% of the cases died from AIDS and 22% from hepatitis C.
In people without a detectable thrombophilia, the cumulative risk of developing thrombosis by the age of 60 is about 12%. About 60% of people who are deficient in antithrombin will have experienced thrombosis at least once by age 60, as will about 50% of people with protein C deficiency and about a third of those with protein S deficiency. People with activated protein C resistance (usually resulting from factor V Leiden), in contrast, have a slightly raised absolute risk of thrombosis, with 15% having had at least one thrombotic event by the age of sixty. In general, men are more likely than women to experience repeated episodes of venous thrombosis.
People with factor V Leiden are at a relatively low risk of thrombosis, but may develop thrombosis in the presence of an additional risk factor, such as immobilization. Most people with the prothrombin mutation (G20210A) never develop thrombosis.
The prevalence of vWD is about one in 100 individuals. However, the majority of these people do not have symptoms. The prevalence of clinically significant cases is one per 10,000. Because most forms are rather mild, they are detected more often in women, whose bleeding tendency shows during menstruation. It may be more severe or apparent in people with blood type O.
Haemophilia C is caused by a deficiency of coagulation factor XI and is distinguished from haemophilia A and B by the fact it does not lead to bleeding into the joints. Furthermore, it has autosomal recessive inheritance, since the gene for factor XI is located on chromosome 4 (near the prekallikrein gene); and it is not completely recessive, individuals who are heterozygous also show increased bleeding.
Many mutations exist, and the bleeding risk is not always influenced by the severity of the deficiency. Hemophilia C is developed on occasion in individuals with systemic lupus erythematosus, because of inhibitors to the FXI protein.
Hypoprothrombinemia can be the result of a genetic defect, may be acquired as the result of another disease process, or may be an adverse effect of medication. For example, 5-10% of patients with systemic lupus erythematosus exhibit acquired hypoprothrombinemia due to the presence of autoantibodies which bind to prothrombin and remove it from the bloodstream (lupus anticoagulant-hypoprothrombinemia syndrome). The most common viral pathogen that is involved is Adenovirus, with a prevalence of 50% in postviral cases.
Inheritance:
Autosomal recessive condition in which both parents must carry the recessive gene in order to pass the disease on to offspring. If both parents have the autosomal recessive condition, the chance of mutation in offspring increases to 100%. An individual will be considered a carrier if one mutant copy of the gene is inherited, and will not illustrate any symptoms. The disease affects both men and women equally, and overall, is a very uncommon inherited or acquired disorder.
Non-inheritance and other factors:
There are two types of prothrombin deficiencies that occur depending on the mutation:
Type I (true deficiency), includes a missense or nonsense mutation, essentially decreasing prothrombin production. This is associated with bleeding from birth. Here, plasma levels of prothrombin are typically less than 10% of normal levels.
Type II, known as dysprothrombinemia, includes a missense mutation at specific Xa factor cleavage sites and serine protease prothrombin regions. Type II deficiency creates a dysfunctional protein with decreased activity and usually normal or low-normal antigen levels. A vitamin K-dependent clotting factor is seldom seen as a contributor to inherited prothrombin deficiencies, but lack of Vitamin K decreases the synthesis of prothrombin in liver cells.
Acquired underlying causes of this condition include severe liver disease, warfarin overdose, platelet disorders, and disseminated intravascular coagulation (DIC).
It may also be a rare adverse effect to Rocephin.
Protein S deficiency is a disorder associated with increased risk of venous thrombosis. Protein S, a vitamin K-dependent physiological anticoagulant, acts as a nonenzymatic cofactor to activate protein C in the degradation of factor Va and factor VIIIa. Decreased (antigen) levels or impaired function of protein S leads to decreased degradation of factor Va and factor VIIIa and an increased propensity to venous thrombosis. Protein S circulates in human plasma in two forms: approximately 60 percent is bound to complement component C4b β-chain while the remaining 40 percent is free, only free protein S has activated protein C cofactor activity
Fresh frozen plasma and cryoprecipitate are the mainstay of therapy for Factor XIII deficiency, but carry risk related to transfusion.
Due to the rarity of Purpura fulminans and its occurrence in vulnerable patient groups like children research on the condition is very limited and evidence based knowledge is scarce. Currently, there is only one Purpura fulminans related clinical research project, http://www.sapfire-registry.org/, which is registered with clinicaltrials.gov.
Hypoprothrombinemia is found to present itself as either inherited or acquired, and is a decrease in the synthesis of prothrombin. In the process of inheritance, it marks itself as an autosomal recessive disorder, meaning that both parents must be carriers of the defective gene in order for the disorder to be present in a child. Prothrombin is a glycoprotein that occurs in blood plasma and functions as a precursor to the enzyme, thrombin, which acts to convert fibrinogen into fibrin, therefore, fortifying clots. This clotting process is known as coagulation.
The mechanism specific to prothrombin (factor II) includes the proteolytically cleaving, breakdown of proteins into smaller polypeptides or amino acids, of this coagulation factor in order to form thrombin at the beginning of the cascade, leading to stemming of blood loss. A mutation in factor II would essentially lead to hypoprothrombinemia. The mutation is presented on chromosome 11.
Areas where the disease has been shown to present itself at include the liver, since the glycoprotein is stored in this area.
Acquired cases are results from an isolated factor II deficiency. Specific cases include:
1. Vitamin-K Deficiency: In the liver, vitamin K plays an important role in the synthesis of coagulation factor II. Body's capacity in the storage of vitamin K is typically very low. Vitamin K-dependent coagulation factors have a very short half-life, sometimes leading to a deficiency when a depletion of vitamin K occurs. The liver synthesizes inactive precursor proteins in the absence of vitamin K (liver disease). Vitamin K deficiency leads to impaired clotting of the blood and in some cases, causes internal bleeding without an associated injury.
2. Disseminated Intravascular Coagulation (DIC): Involving abnormal, excessive generation of thrombin and fibrin within the blood. Relative to hypoprothrombinemia, due to increased platelet aggregation and coagulation factor consumption involved in the process.
3. Anticoagulants: Warfarin Overdose: Used as a treatment for prevention of blood clots, however, like most drugs, side effects have been shown to increase risk of excessive bleeding by functioning in the disruption of hepatic synthesis of coagulation factors II, VII, IX, and X. Vitamin K is an antagonist to warfarin drug, reversing its activity, causing it to be less effective in the process of blood clotting. Warfarin intake has been shown to interfere with Vitamin-K metabolism.
Protein C is vitamin K-dependent. Patients with Protein C deficiency are at an increased risk of developing skin necrosis while on warfarin. Protein C has a short half life (8 hour) compared with other vitamin K-dependent factors and therefore is rapidly depleted with warfarin initiation, resulting in a transient hypercoagulable state.
Haemophilia C (also known as plasma thromboplastin antecedent (PTA) deficiency or Rosenthal syndrome) is a mild form of haemophilia affecting both sexes, due to factor XI deficiency. However, it predominantly occurs in Jewish people of Ashkenazi descent. It is the fourth most common coagulation disorder after von Willebrand's disease and haemophilia A and B. In the United States, it is thought to affect 1 in 100,000 of the adult population, making it 10% as common as haemophilia A.
The incidence of acute TTP in adults is around 1.7–4.5 per million and year. These cases are nearly all due to the autoimmune form of TTP, where autoantibodies inhibit ADAMTS13 activity. The prevalence of USS has not yet been determined but is assumed to constitute less than 5% of all acute TTP cases. The syndrome's inheritance is autosomal recessive, and is more often caused by compound heterozygous than homozygous mutations. The age of onset is variable and can be from neonatal age up to the 5th–6th decade. The risk of relapses differs between affected individuals. Minimization of the burden of disease can be reached by early diagnosis and initiation of prophylaxis if required.
Von Willebrand disease can also affect some breeds of dogs, notably the Doberman Pinscher, and screening is offered for known breeds.
There are autoimmune causes of coagulation disorders. They include acquired antibodies to coagulation factors, termed inhibitors of coagulation. The main inhibitor is directed against clotting Factor VIII. Another example is antiphospholipid syndrome an autoimmune, hypercoagulable state.
While it is indicated that people with FXII deficiency are generally asymptomatic, studies in women with recurrent miscarriages suggest an association with FXII deficiency.
The condition is of importance in the differential diagnosis to other bleeding disorders, specifically the hemophilias: hemophilia A with a deficiency in factor VIII or antihemophilic globulin, hemophilia B with a deficiency in factor IX (Christmas disease), and hemophilia C with a deficiency in factor XI. Other rare forms of bleeding disorders are also in the differential diagnosis.
There is concern that individuals with FXII deficiency are more prone to thrombophilic disease, however, this is at variance with a long term study from Switzerland.
Factor XIII deficiency occurs exceedingly rarely, causing a severe bleeding tendency. The incidence is one in a million to one in five million people, with higher incidence in areas with consanguineous marriage such as Iran that has the highest global incidence of the disorder. Most are due to mutations in the A subunit gene (located on chromosome 6p25-p24). This mutation is inherited in an autosomal recessive fashion.
Deficiency of Factor XIII leads to defective cross-linking of fibrin and vulnerability to late re-bleeds when the primary hemostatic plug is overwhelmed. Bleeding tendencies similar to hemophiliacs develop, such as hemarthroses and deep tissue bleeding.
As Factor XIII is composed of two subunit protein, A and B, for which the genes are located on different chromosomes, administration of recombinant A subunit improves clot stability and is becoming a therapeutic option for patients with this condition.
Inherited or congenital FVII deficiency is passed on by autosomal recessive inheritance. A person needs to inherit a defective gene from both parents. People who have only one defective gene do not exhibit the disease, but can pass the gene on to half their offspring. Different genetic mutations have been described.
In persons with the congenital FVII deficiency the condition is lifelong. People with this condition should alert other family members may they also have the condition or carry the gene. In the general population the condition affects about 1 in 300,000 to 500,000 people. However, the prevalence may be higher as not all individuals may express the disease and be diagnosed.
In the acquired of FVII deficiency an insufficient amount of factor VII is produced by the liver due to liver disease, vitamin K deficiency, or certain medications (i.e. Coumadin).
Newborns are relatively vitamin K deficient for a variety of reasons. They have low vitamin K stores at birth, vitamin K passes the placenta poorly, the levels of vitamin K in breast milk are low and the gut flora has not yet been developed (vitamin K is normally produced by intestinal bacteria).
The major ("type 1") thrombophilias are rare. Antithrombin deficiency is present in 0.2% of the general population and 0.5–7.5% of people with venous thrombosis. Protein C deficiency, too, is present in 0.2% of the population, and can be found in 2.5–6% of people with thrombosis. The exact prevalence of protein S deficiency in the population is unknown; it is found 1.3–5% of people with thrombosis.
The minor ("type 2") thrombophilias are much more common. Factor V Leiden is present in 5% of the population of Northern European descent, but much rarer in those of Asian or African extraction. In people with thrombosis, 10% have factor V Leiden. In those who are referred for thrombophilia testing, 30–50% have the defect. The prothrombin mutation occurs at rates of 1–4% in the general population, 5–10% of people with thrombosis, and 15% of people referred for thrombophilia testing. Like factor V Leiden, this abnormality is uncommon in Africans and Asians.
The exact prevalence of antiphospholipid syndrome is not well known, as different studies employ different definitions of the condition. Antiphospholipid antibodies are detected in 24% of those referred to thrombophilia testing.
Inherited or congenital FX deficiency is usually passed on by autosomal recessive inheritance. A person needs to inherit a defective gene from both parents. People who have only one defective gene are asymptomatic, but may have lower FXII levels and can pass the gene on to half their offspring.
In persons with congenital FXII deficiency the condition is lifelong. People affected may want to alert other family members as they may also may carry the gene. A 1994 study of 300 healthy blood donors found that 7 persons (2.3%) had FXII deficiencies with one subject having no detectable FXII (0.3%). This study is at variance with estimates that only 1 in 1,000,000 people has the condition.
The acquired form of FXII deficiency is seen in patients with the nephrotic syndrome, liver disease, sepsis and shock, disseminated intravascular coagulation, and other diseases.
Two Dutch studies have followed hemophilia patients for a number of years. Both studies found that viral infections were common in hemophiliacs due to the frequent blood transfusions which put them at risk of getting blood borne infections such as HIV and hepatitis C. In the latest study which followed patients from 1992 to 2001, the male life expectancy was 59 years. If cases with known viral infections were excluded, the life expectancy was 72, close to that of the general population. 26% of the cases died from AIDS and 22% from hepatitis C.