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At present there is no specific treatment. Many patients with haemolytic anaemia take folic acid (vitamin B) since the greater turnover of cells consumes this vitamin. During crises transfusion may be required. Clotting problems can occur for which anticoagulation may be needed. Unlike hereditary spherocytosis, splenectomy is contraindicated.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
Hereditary stomatocytosis describes a number of inherited autosomal dominant human conditions which affect the red blood cell, in which the membrane or outer coating of the cell 'leaks' sodium and potassium ions.
Experimental gene therapy exists to treat hereditary spherocytosis in lab mice; however, this treatment has not yet been tried on humans due to all of the risks involved in human gene therapy.
HPFH may alleviate the severity of certain hemoglobinopathies and thalassemias, and is selected for in populations with a high prevalence of these conditions (which in turn are often selected for in areas where malaria is endemic). Thus, it has been found to affect Americans of African and Greek descent.
Hereditary spherocytosis is the most common disorder of the red cell membrane and affects 1 in 2,000 people of Northern European ancestry. According to Harrison's Principles of Internal Medicine, the frequency is at least 1 in 5,000.
Congenital dyserythropoietic anemia type II (CDA II), or hereditary erythroblastic multinuclearity with positive acidified serum lysis test (HEMPAS) is a rare genetic anemia in humans characterized by hereditary erythroblastic multinuclearity with positive acidified serum lysis test.
Genetic testing for the presence of mutations in protein molecules is considered to be a confirmatory testing technique. It is important to know the risks regarding the transmission and dangers of HPP.
Hereditary pyropoikilocytosis (HPP) is an autosomal recessive form of hemolytic anemia characterized by an abnormal sensitivity of red blood cells to heat and erythrocyte morphology similar to that seen in thermal burns. Patients with HPP tend to experience severe haemolysis and anaemia in infancy that gradually improves, evolving toward typical elliptocytosis later in life. However, the hemolysis can lead to rapid sequestration and destruction of red cells. Splenectomy is curative when this occurs.
HPP has been associated with a defect of the erythrocyte membrane protein spectrin and with spectrin deficiency.It was characterized in 1975.It is considered a severe form of hereditary elliptocytosis.
In persons with sickle cell disease, high levels of fetal hemoglobin as found in a newborn or as found abnormally in persons with hereditary persistence of fetal hemoglobin, the HbF causes the sickle cell disease to be less severe. In essence the HbF inhibits polymerization of HbS. A similar mechanism occurs with persons who have sickle cell "trait". Approximately 40% of the hemoglobin is in the HbS form while the rest is in normal HbA form. The HbA form interferes with HbS polymerization.
Hereditary elliptocytosis, also known as ovalocytosis, is an inherited blood disorder in which an abnormally large number of the patient's erythrocytes (i.e. red blood cells) are elliptical rather than the typical disc shape. Such morphologically distinctive erythrocytes are sometimes referred to as elliptocytes or ovalocytes. It is one of many red-cell membrane defects. In its severe forms, this disorder predisposes to haemolytic anaemia. Although pathological in humans, elliptocytosis is normal in camelids.
Those with hereditary elliptocytosis have a good prognosis, only those with very severe disease have a shortened life expectancy.
Effective treatment of the disease has been confined to liver transplants. Success has also been reported with an antioxidant chelation cocktail, though its effectiveness cannot be confirmed. Based on the alloimmune cause hypothesis, a new treatment involving high-dose immunoglobulin to pregnant mothers who have had a previous pregnancy with a confirmed neonatal hemochromatosis outcome, has provided very encouraging results.
Southeast Asian ovalocytosis is a blood disorder that is similar to, but distinct from hereditary elliptocytosis. It is common in some communities in Malaysia and Papua New Guinea, as it confers some resistance to cerebral Falciparum Malaria.
Harderoporphyria is a rare disorder of heme biosynthesis, inherited in an autosomal recessive manner caused by specific mutations in the "CPOX" gene. Mutations in "CPOX" usually cause hereditary coproporphyria, an acute hepatic porphyria, however the K404E mutation in a homozygous or compound heterozygous state with a null allele cause the more severe harderoporphyria. Harderoporphyria is the first known metabolic disorder where the disease phenotype depended on the type and location of the mutations in a gene associated with multiple disorders.
In contrast with other porphyrias, which typically present with either cutaneous lesions after exposure to sunlight or acute neurovisceral attack at any age (most commonly in adulthood), harderoporphyria is characterized by jaundice, anemia enlarged liver and spleen, often presenting in the neonatal period. Later in life, these individuals may present with photosensitivity similar to that found in cutaneous porphyrias.
Biochemically, harderoporphyria presents with a distinct pattern of increased harderoporphyrin (2-vinyl-4,6,7-tripropionic acid porphyrin) in urine and particularly in feces, a metabolite that is not seen in significant quantities in any other porphyria. Enzyme tests show markedly reduced activity of coproporphyrinogen oxidase, compared to both unaffected individuals and those affected with hereditary coproporphyria, consistent with recessive inheritance.
Harderoporphyria is a rare condition, with less than 10 cases reported worldwide. It may be underdiagnosed, as it does not have the typical presentation associated with a porphyria. It was identified as a variant type of coproporphyria in 1983, in a family with three children identified at birth with jaundice and hemolytic anemia. There is no standard treatment for harderoporphyria; care is mainly focused on the management of symptoms.
Administration of cytidine monophosphate and uridine monophosphate reduces urinary orotic acid and ameliorates the anemia.
Administration of uridine, which is converted to UMP, will bypass the metabolic block and provide the body with a source of pyrimidine.
Uridine triacetate is a drug approved by FDA to be used in the treatment of hereditary orotic aciduria.
Routine treatment in an otherwise-healthy person consists of regularly scheduled phlebotomies (bloodletting or erythrocytapheresis). When first diagnosed, the phlebotomies may be fairly frequent, until iron levels can be brought to within normal range. Once iron and other markers are within the normal range, treatments may be scheduled every other month or every three months depending upon the underlying cause of the iron overload and the person's iron load. A phlebotomy session typically draws between 450 to 500 cc whole blood.
For those unable to tolerate routine blood draws, there is a chelating agent available for use. The drug deferoxamine binds with iron in the bloodstream and enhances its elimination in urine and faeces. Typical treatment for chronic iron overload requires subcutaneous injection over a period of 8–12 hours daily. Two newer iron chelating drugs that are licensed for use in patients receiving regular blood transfusions to treat thalassaemia (and, thus, who develop iron overload as a result) are deferasirox and deferiprone.
Studies indicate that persons with symptomatic haemochromatosis have somewhat reduced life expectancy compared to the general population. This is mainly due to excess mortality from cirrhosis and liver cancer. Patients who were treated with phlebotomy lived longer than those who weren't. Patients without liver disease or diabetes had similar survival rate to the general population.
Clinical development of several new active substances, which intervene in the disease process in different ways, is currently ongoing.
Pharming Group NV announced on 24 June 2010 that the European Medicines Agency has adopted a positive opinion on conestat alfa (trade name Ruconest), a C1-inhibitor for the treatment of acute angioedema attacks.
Ecallantide, a peptide inhibitor of kallikrein, has received orphan status for HAE and has shown positive results in phase III trials.
Icatibant (marketed as Firazyr) is a selective bradykinin receptor antagonist, which has been approved in Europe and was approved in the USA by the FDA in Aug 2011. After initial borderline results this drug was shown to be effective in phase III trials. Cinryze has been approved by the FDA in October 2008.
It is most common in certain European populations (such as the Irish and Norwegians) and occurs in 0.6% of the population. Men with the disease are 24 times more likely to experience symptoms than affected women.
Individuals experiencing episodic bleeding as a result of congenital dysfibrinogenemia should be treated at a center specialized in treating hemophilia. They should avoid all medications that interfere with normal platelet function. During bleeding episodes, treatment with fibrinogen concentrates or in emergencies or when these concentrates are unavailable, infusions of fresh frozen plasma and/or cryoprecipitate (a fibrinogen-rich plasma fraction) to maintain fibrinogen activity levels >1 gram/liter. Tranexamic acid or fibrinogen concentrates are recommended for prophylactic treatment prior to minor surgery while fibrinogen concentrates are recommended prior to major surgery with fibrinogen concentrates usage seeking to maintain fibrinogen activity levels at >1 gram/liter. Women undergoing vaginal or Cesarean child birth should be treated at a hemophilia center with fibrinogen concentrates to maintain fibrinogen activity levels at 1.5 gram/liter. The latter individuals require careful observation for bleeding during their post-partum periods.
Individuals experiencing episodic thrombosis as a result of congenital dysfibrinogenemia should also be treated at a center specialized in treating hemophilia using antithrombotic agents. They should be instructed on antithrombotic behavioral methods fur use in high risk situations such as long car rides and air flights. Venous thrombosis should be treated with low molecular weight heparin for a period that depends on personal and family history of thrombosis events. Prophylactic treatment prior to minor surgery should avoid fibrinogen supplementation and use prophylactic anticoagulation measures; prior to major surgery, fibrinogen supplementation should be used only if serious bleeding occurs; otherwise, prophylactic anticoagulation measures are recommended.
Where venesection is not possible, long-term administration of desferrioxamine mesylate is useful. Desferrioxamine is an iron-chelating compound, and excretion induced by desferrioxamine is enhanced by administration of Vitamin C. It cannot be used during pregnancy or breast-feeding due to risk of defects in the child.
Treatment of acquired dysfibrinogenemia follows the guidelines recommended for congenital dysfibrinogenemia. In addition, treatment of any disease thought to be responsible for the dysfibrinogenemia might be useful. For example, therapeutic plasma exchange and chemotherapy to reduce monoclonal antibody levels has been used successfully to reverse otherwise uncontrollable bleeding in cases of multiple myeloma-associated dysfibrinogenemia.
The condition is sometimes confused with juvenile hemochromatosis, which is a hereditary hemochromatosis caused by mutations of a gene called hemojuvelin. While the symptoms and outcomes for these two diseases are similar, the causes appear to be different.
It is hereditary haemolytic anaemia in which the red blood cell is oval-shaped. The primary defect in SAO differs significantly from other forms of elliptocytosis in that it is a defect in the gene coding for a protein that is not directly involved in the cytoskeleton scaffolding of the cell. Rather, the defect lies in a protein known as the band 3 protein, which lies in the cell membrane itself. The band 3 protein normally binds to another membrane-bound protein called ankyrin, but in SAO this bond is stronger than normal. Other abnormalities include tighter tethering of the band 3 protein to the cell membrane, increased tyrosine phosphorylation of the band 3 protein, reduced sulfate anion transport through the cell membrane, and more rapid ATP consumption. These (and probably other) consequences of the SAO mutations lead to the following erythrocyte abnormalities:
- A greater robustness of cells to a variety of external forces, including:
- Reduction in cellular sensitivity to osmotic pressures
- Reduction in fragility related to temperature change
- greater general rigidity of the cell membrane
- Loss of sensitivity to substances that cause of cells
- Reduced anion exchange
- Partial intracellular depletion of ATP
- A reduction in expression of multiple antigens
These changes are thought to give rise to the scientifically and clinically interesting phenomenon that those with SAO exhibit: a marked "in vivo" resistance to infection by the causative pathogen of malaria, "Plasmodium falciparum". Unlike those with the Leach phenotype of common hereditary elliptocytosis (see above), there is a clinically significant reduction in both disease severity and prevalence of malaria in those with SAO. Because of this, the 35% incidence rate of SAO along the north coast of Madang Province in Papua New Guinea, where malaria in endemic, is a good example of natural selection.
The reasons behind the resistance to malaria become clear when given an explanation the way in which "Plasmodium falciparum" invades its host. This parasite is an obligate intracellular parasite, which must enter the cells of the host it is invading. The band 3 proteins aggregate on the cell membrane at the site of entry, forming a circular that the parasite squeezes through. These band 3 proteins act as receptors for the parasite. Normally a process much like endocytosis occurs, and the parasite is able to isolate itself from the intracellular proteins that are toxic to it while still being inside an erythrocyte (see figure 2). The increased rigidity of the erythrocyte membrane in SAO is thought to reduce the capacity of the band 3 proteins to cluster together, thereby making it more difficult for the malaria parasite to properly attaching to and enter the cell. The reduced free ATP within the cell has been postulated as a further mechanism behind which SAO creates a hostile environment for "Plasmodium falciparum".