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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.
Occasionally, the anemia is so severe that support with transfusion is required. These patients usually do not respond to erythropoietin therapy. Some cases have been reported that the anemia is reversed or heme level is improved through use of moderate to high doses of pyrodoxine (vitamin B). In severe cases of SBA, bone marrow transplant is also an option with limited information about the success rate. Some cases are listed on MedLine and various other medical sites. In the case of isoniazid-induced sideroblastic anemia, the addition of B is sufficient to correct the anemia. Desferrioxamine, a chelating agent, is used to treat iron overload from transfusions.
Therapeutic phlebotomy can be used to manage iron overload.
Sideroblastic anemias are often described as responsive or non-responsive in terms of increased hemoglobin levels to pharmacological doses of vitamin B.
1- Congenital: 80% are responsive, though the anemia does not completely resolve.
2- Acquired clonal: 40% are responsive, but the response may be minimal.
3- Acquired reversible: 60% are responsive, but course depends on treatment of the underlying cause.
Severe refractory sideroblastic anemias requiring regular transfusions and/or that undergo leukemic transformation (5-10%) significantly reduce life expectancy.
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.
The American College of Obstetricians and Gynecologists recommends all people thinking of becoming pregnant be tested to see if they have thalassemia. Genetic counseling and genetic testing are recommended for families who carry a thalassemia trait.
A screening policy exists in Cyprus to reduce the rate of thalassemia, which, since the program's implementation in the 1970s (which also includes prenatal screening and abortion), has reduced the number of children born with the disease from one of every 158 births to almost zero.
In Iran as a premarital screening, the man's red cell indices are checked first, if he has microcytosis (mean cell hemoglobin < 27 pg or mean red cell volume < 80 fl), the woman is tested. When both are microcytic, their hemoglobin A2 concentrations are measured. If both have a concentration above 3.5% (diagnostic of thalassemia trait) they are referred to the local designated health post for genetic counseling.
Large scale awareness campaigns are being organized in India both by government and non-government organizations in favor of voluntary premarital screening to detect carriers of thalassemia and marriage between both carriers are strongly discouraged.
Beta thalassemia is a hereditary disease allowing for a preventative treatment by carrier screening and prenatal diagnosis. It can be prevented if one parent has normal genes, giving rise to screenings that empower carriers to select partners with normal hemoglobin. A study aimed at detecting the genes that could give rise to offspring with sickle cell disease. Patients diagnosed with beta thalassemia have MCH ≤ 26 pg and an RDW < 19. Of 10,148 patients, 1,739 patients had a hemoglobin phenotype and RDW consistent with beta thalassemia. After the narrowing of patients, the HbA2 levels were tested presenting 77 patients with beta thalassemia. This screening procedure proved insensitive in populations of West African ancestry because of the indicators has high prevalence of alpha thalassemia. Countries have programs distributing information about the reproductive risks associated with carriers of haemoglobinopathies. Thalassemia carrier screening programs have educational programs in schools, armed forces, and through mass media as well as providing counseling to carriers and carrier couples. Screening has showed reduced incidence; by 1995 the prevalence in Italy reduced from 1:250 to 1:4000, and a 95% decrease in that region. The decrease in incidence has benefitted those affected with thalassemia, as the demand for blood has decreased, therefore improving the supply of treatment.
Iron overload is an unavoidable consequence of chronic transfusion therapy, necessary for patients with beta thalassemia. Iron chelation is a medical therapy that avoids the complications of iron overload. The iron overload can be removed by Deferasirox, an oral iron chelator, which has a dose- dependent effect on iron burden. Every unit of transfused blood contains 200–250 mg of iron and the body has no natural mechanism to remove excess iron. Deferasirox is a vital part in the patients health after blood transfusions. During normal iron homeostasis the circulating iron is bound to transferrin, but with an iron overload, the ability for transferrin to bind iron is exceeded and non-transferrin bound iron is formed. It represents a potentially toxic iron form due to its high propensity to induce oxygen species and is responsible for cellular damage. The prevention of iron overload protects patients from morbidity and mortality. The primary aim is to bind to and remove iron from the body and a rate equal to the rate of transfusional iron input or greater than iron input. During clinical trails patients that received Deferasirox experienced no drug-related neutropenia or agranulocytosis, which was present with other iron chelators. Its long half life requires it to be taken once daily and provides constant chelation. Cardiac failure is a main cause of illness from transfusional iron overload but deferasirox demonstrated the ability to remove iron from iron-loaded myocardial cells protecting beta thalassemia patients from effects of required blood transfusions.
Definitive therapy depends on the cause:
- Symptomatic treatment can be given by blood transfusion, if there is marked anemia. A positive Coombs test is a relative contraindication to transfuse the patient. In cold hemolytic anemia there is advantage in transfuse warmed blood
- In severe immune-related hemolytic anemia, steroid therapy is sometimes necessary.
- In steroid resistant cases, consideration can be given to rituximab or addition of an immunosuppressant ( azathioprine, cyclophosphamide)
- Association of methylprednisolone and intravenous immunoglobulin can control hemolysis in acute severe cases
- Sometimes splenectomy can be helpful where extravascular hemolysis, or hereditary spherocytosis, is predominant (i.e., most of the red blood cells are being removed by the spleen).
Gene therapy, as well as, bone marrow transplant are also possible treatments for the disorder, but each have their own risks at this point in time. Bone marrow transplantation is the more used method between the two, whereas researchers are still trying to definitively establish the results of gene therapy treatment. It generally requires a 10/10 HLA matched donor, however, who is usually a sibling. As most patients do not have this, they must rely on gene therapy research to potentially provide them with an alternative. CDA at both clinical and genetic aspects are part of a heterogeneous group of genetic conditions. Gene therapy is still experimental and has largely only been tested in animal models until now. This type of therapy has promise, however, as it allows for the autologous transplantation of the patient's own healthy stem cells rather than requiring an outside donor, thereby bypassing any potential for graft vs. host disease (GVHD).
In the United States, the FDA approved clinical trials on Beta thalassemia patients in 2012. The first study, which took place in July 2012, recruited human subjects with thalassemia major, and ended in 2014.
Treatments for anemia depend on cause and severity. Vitamin supplements given orally (folic acid or vitamin B) or intramuscularly (vitamin B) will replace specific deficiencies.
Nutritional iron deficiency is common in developing nations. An estimated two-thirds of children and of women of childbearing age in most developing nations are estimated to suffer from iron
deficiency; one-third of them have the more severe form of the disorder, anemia. Iron deficiency from nutritional causes is rare in men and postmenopausal women. The diagnosis of iron deficiency mandates a search for potential sources of loss, such as gastrointestinal bleeding from ulcers or colon cancer. Mild to moderate iron-deficiency anemia is treated by oral iron supplementation with ferrous sulfate, ferrous fumarate, or ferrous gluconate. When taking iron supplements, stomach upset or darkening of the feces are commonly experienced. The stomach upset can be alleviated by taking the iron with food; however, this decreases the amount of iron absorbed. Vitamin C aids in the body's ability to absorb iron, so taking oral iron supplements with orange juice is of benefit. In anemias of chronic disease, associated with chemotherapy, or associated with renal disease, some clinicians prescribe recombinant erythropoietin or epoetin alfa, to stimulate RBC production, although since there is also concurrent iron deficiency and inflammation present, parenteral iron is advised to be taken concurrently.
Bone marrow transplantation may offer the possibility of a cure in young people who have an HLA-matched donor. Success rates have been in the 80–90% range. Mortality from the procedure is about 3%. There are no randomized controlled trials which have tested the safety and efficacy of non-identical donor bone marrow transplantation in persons with β- thalassemia who are dependent on blood transfusion.
If the person does not have an HLA-matched compatible donor, another method called bone marrow transplantation (BMT) from haploidentical mother to child (mismatched donor) may be used. In a study of 31 people, the thalassemia-free survival rate 70%, rejection 23%, and mortality 7%. The best results are with very young people.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
Hemolytic anemia affects nonhuman species as well as humans. It has been found, in a number of animal species, to result from specific triggers.
Some notable cases include hemolytic anemia found in black rhinos kept in captivity, with the disease, in one instance, affecting 20% of captive rhinos at a specific facility. The disease is also found in wild rhinos.
Dogs and cats differ slightly from humans in some details of their RBC composition and have altered susceptibility to damage, notably, increased susceptibility to oxidative damage from consumption of onion. Garlic is less toxic to dogs than onion.
Treatment of individuals with CDA usually consist of frequent blood transfusions, but this can vary depending on the type that the individual has. Patients report going every 2–3 weeks for blood transfusions. In addition, they must undertake chelation therapy to survive; either deferoxamine, deferasirox, or deferiprone to eliminate the excess iron that accumulates. Removal of the spleen and gallbladder are common. Hemoglobin levels can run anywhere between 8.0 g/dl and 11.0 g/dl in untransfused patients, the amount of blood received by the patient is not as important as their baseline pre-transfusion hemoglobin level. This is true for ferritin levels and iron levels in the organs as well, it is important for patients to go regularly for transfusions in order to maximize good health, normal ferritin levels run anywhere between 24 and 336 ng/ml, hematologists generally do not begin chelation therapy until ferritin levels reach at least 1000 ng/ml. It is more important to check iron levels in the organs through MRI scans, however, than to simply get regular blood tests to check ferritin levels, which only show a trend, and do not reflect actual organ iron content.
In terms of treatment for delta-beta thalassemia one possible concern would be anemia, where, therefore, blood transfusions would be given to the affected individual (though blood transfusions might introduce complications, as well).
Stem cell transplant is another option, but the donor and the individual who will receive the bone marrow transplant must be compatible, the risks involved should be evaluated, as well
Ted DeVita died of transfusional iron overload from too many blood transfusions.
The ideal treatment for anemia of chronic disease is to treat the chronic disease successfully, but this is rarely possible.
Parenteral iron is increasingly used for anemia in chronic renal disease and inflammatory bowel disease.
Erythropoietin can be helpful, but this is costly and may be dangerous. Erythropoietin is advised either in conjunction with adequate iron replacement which in practice is intravenous, or when IV iron has proved ineffective.
When treating iron-deficiency anemia, considerations of the proper treatment methods are done in light of the "cause and severity" of the condition. If the iron-deficiency anemia is a downstream effect of blood loss or another underlying cause, treatment is geared toward addressing the underlying cause when possible. In severe acute cases, treatment measures are taken for immediate management in the interim, such as blood transfusions or even intravenous iron.
Iron-deficiency anemia treatment for less severe cases includes dietary changes to incorporate iron-rich foods into regular oral intake. Foods rich in ascorbic acid (vitamin C) can also be beneficial, since ascorbic acid enhances iron absorption. Other oral options are iron supplements in the form of pills or drops for children.
As iron-deficiency anemia becomes more severe, or if the anemia does not respond to oral treatments, other measures may become necessary. In addition to the previously mentioned indication for intravenous iron or blood transfusions, intravenous iron may also be used when oral intake is not tolerated, as well as for other indications. Specifically, for those on dialysis, parenteral iron is commonly used. Individuals on dialysis who are taking forms of erythropoietin or some "erythropoiesis-stimulating agent" are given parenteral iron, which helps the body respond to the erythropoietin agents and produce red blood cells.
The various forms of treatment are not without possible adverse effects. Iron supplementation by mouth commonly causes negative gastrointestinal effects, including constipation. Intravenous iron can induce an allergic response that can be as serious as anaphylaxis, although different formulations have decreased the likelihood of this adverse effect.
Microcytic anaemia is any of several types of anaemia characterized by small red blood cells (called microcytes). The normal mean corpuscular volume (abbreviated to MCV on full blood count results) is 80-100 fL, with smaller cells (100 fL) as macrocytic (the latter occur in macrocytic anemia).The MCV is the average red blood cell size.
In microcytic anaemia, the red blood cells (erythrocytes) are usually also hypochromic, meaning that the red blood cells appear paler than usual. This is reflected by a lower-than-normal mean corpuscular hemoglobin concentration (MCHC), a measure representing the amount of hemoglobin per unit volume of fluid inside the cell; normally about 320-360 g/L or 32-36 g/dL. Typically, therefore, anemia of this category is described as "microcytic, hypochromic anaemia".
Typical causes of microcytic anemia include:
- Childhood
- Iron deficiency anemia, by far the most common cause of anemia in general and of microcytic anemia in particular
- Thalassemia
- Adulthood
- Iron deficiency anemia
- Sideroblastic anemia, In congenital sideroblastic anemia the MCV (mean corpuscular volume) is either low or normal. In contrast, the MCV is usually high in the much more common acquired sideroblastic anemia.
- Anemia of chronic disease, although this more typically causes normochromic, normocytic anemia. Microcytic anemia has been discussed by Weng et al.
- Lead poisoning
- Vitamin B (pyridoxine) deficiency
Other causes that are typically thought of as causing normocytic anemia or macrocytic anemia must also be considered, and the presence of two or more causes of anemia can distort the typical picture.
There are five main causes of microcytic anemia forming the acronym TAILS. Thalassemia, Anemia of chronic disease, Iron deficiency, Lead poisoning and Congenital sideroblastic anemia. Only the first three are common in most parts of the world. In theory, these three can be differentiated by their red blood cell (RBC) morphologies. Anemia of chronic disease shows unremarkable RBCs, iron deficiency shows anisocytosis, anisochromia and elliptocytosis, and thalessemias demonstrate target cells and coarse basophilic stippling. In practice though elliptocytes and anisocytosis are often seen in thalessemia and target cells occasionally in iron deficiency. All three may show unremarkable RBC morphology. Coarse basophlic stippling is one reliable morphologic finding of thalessemia which does not appear in iron deficiency or anemia of chronic disease. The patient should be in an ethnically at risk group and the diagnosis is not confirmed without a confirmatory method such as hemoglobin HPLC, H body staining, molecular testing or another reliable method. Course basophlic stippling occurs in other cases as seen in Table 1
Treatment is by phlebotomy, erythrocytapheresis or chelation therapy with iron chelating agents such as deferoxamine, deferiprone or deferasirox.
If iron overload has caused end-organ damage, this is generally irreversible and may require transplantation.
Microcytic anemia is not caused by reduced DNA synthesis.
Thalassemia can cause microcytosis. Depending upon how the terms are being defined, thalassemia can be considered a cause of microcytic anemia, or it can be considered a cause of microcytosis but not a cause of microcytic anemia.
There are many causes of microcytosis, which is essentially only a descriptor. Cells can be small because of mutations in the formation of blood cells (hereditary microcytosis) or because they are not filled with enough hemoglobin, as in iron-deficiency-associated microcytosis.
Red blood cells can be characterised by their haemoglobin content as well as by their size. The haemoglobin content is referred to as the cell's colour. Therefore, there are both "normochromic microcytotic red cells" and "hypochromic, microcytotic red cells". The normochromic cells have a normal concentration of haemoglobin, and are therefore 'red enough' while the hypochromic cells do not; thus the value of the mean corpuscular hemoglobin concentration.
Corticosteroids can be used to treat anemia in DBA. In a large study of 225 patients, 82% initially responded to this therapy, although many side effects were noted. Some patients remained responsive to steroids, while efficacy waned in others. Blood transfusions can also be used to treat severe anemia in DBA. Periods of remission may occur, during which transfusions and steroid treatments are not required. Bone marrow transplantation (BMT) can cure hematological aspects of DBA. This option may be considered when patients become transfusion-dependent because frequent transfusions can lead to iron overloading and organ damage. However, adverse events from BMTs may exceed those from iron overloading. A 2007 study showed the efficacy of leucine and isoleucine supplementation in one patient. Larger studies are being conducted.
Normocytic anemia is a type of anemia and is a common issue that occurs for men and women typically over 85 years old. Its prevalence increases with age, reaching 44 percent in men older than 85 years.