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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.
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.
Long-term transfusion therapy to maintain the patient’s hemoglobin level above 9-10 g/dL (normal levels are 13.8 for males, and 12.1 for females). Patients are transfused by meeting strict criteria ensuring their safety. They must have: confirmed laboratory diagnosis of thalassemia major, and hemoglobin levels less than 7g/dL, to be eligible for the transfusion. To ensure quality blood transfusions, the packed red blood cells should be leucoreduced with a minimum of 40g of hemoglobin content. By having leucoreduced blood packets, the patient is at a lower risk to develop adverse reactions by contaminated white cells and preventing platelet alloimmunisation. Pre-storage filtration of whole blood offers high efficiency for removal and low residual of leukocytes; It is the preferred method of leucoreduction compared to pre-transfusion and bedside filtration. Patients with allergic transfusion reactions or unusual red cell antibodies must received “washed red cells” or “cryopreserved red cells.” Washed red cells have been removed of plasma proteins that would have become a target of the patient’s antibodies allowing the transfusion to be carried out safely. Cryopreserved red cells are used to maintain a supply of rare donor units for patients with unusual red cell antibodies or missing common red cell antigens. The transfusion programs available involve lifelong regular blood transfusion to main the pre-transfusion hemoglobin level above 9-10 g/gL. The monthly transfusions promote normal growth, physical activities, suppress bone marrow activity, and minimize iron accumulation. It has been announced the starting of the first clinical trial with CRISPR/Cas9 in Europe in 2018.
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.
Multiple blood transfusions can result in iron overload. The iron overload related to thalassemia may be treated by chelation therapy with the medications deferoxamine, deferiprone, or deferasirox. These treatments have resulted in improving life expectancy in those with thalassemia major.
Deferoxamine is only effective via daily injections which makes its long-term use more difficult. It has the benefit of being inexpensive and decent long-term safety. Adverse effects are primary skin reactions around the injection site and hearing loss.
Deferasirox has the benefit of being an oral medication. Common side effects include: nausea, vomiting and diarrhea. It however is not effective in everyone and is probably not suitable in those with significant cardiac issues related to iron overload. The cost is also significant.
Deferiprone is a medication that is given by mouth. Nausea, vomiting, and diarrhea are relatively common with its use. It is available in both Europe and the United States. It appears to be the most effective agent when the heart is significantly involved.
There is no evidence from randomized controlled trial to support zinc supplementation in thalassemia.
In cases where oral iron has either proven ineffective, would be too slow (for example, pre-operatively) or where absorption is impeded (for example in cases of inflammation), parenteral iron can be used. The body can absorb up to 6 mg iron daily from the gastrointestinal tract. In many cases the patient has a deficit of over 1,000 mg of iron which would require several months to replace. This can be given concurrently with erythropoietin to ensure sufficient iron for increased rates of erythropoiesis.
Although research is ongoing, at this point there is no cure for the genetic defect that causes hereditary spherocytosis. Current management focuses on interventions that limit the severity of the disease. Treatment options include:
- Splenectomy: As in non-hereditary spherocytosis, acute symptoms of anemia and hyperbilirubinemia indicate treatment with blood transfusions or exchanges and chronic symptoms of anemia and an enlarged spleen indicate dietary supplementation of folic acid and splenectomy, the surgical removal of the spleen. Splenectomy is indicated for moderate to severe cases, but not mild cases. To decrease the risk of sepsis, post-splenectomy spherocytosis patients require immunization against the influenza virus, encapsulated bacteria such as Streptococcus pneumoniae and meningococcus, and prophylactic antibiotic treatment. However, the use of prophylactic antibiotics, such as penicillin, remains controversial.
- Partial splenectomy: Since the spleen is important for protecting against encapsulated organisms, sepsis caused by encapsulated organisms is a possible complication of splenectomy. The option of partial splenectomy may be considered in the interest of preserving immune function. Research on outcomes is currently limited, but favorable.
- Surgical removal of the gallbladder may be necessary.
People with severe thalassemia require medical treatment. A blood transfusion regimen was the first measure effective in prolonging life.
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).
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
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.
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.
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.
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.
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.
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.
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
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.
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.
In 2007, the drug eculizumab was approved for the treatment of PNH. It improves quality of life and decreases the need for blood transfusions but does not appear to affect the risk of death. It does not appear to change the risk of blood clots, myelodysplastic syndrome, acute myelogenous leukemia, or aplastic anemia.
Eculizumab is controversial due to its high cost, as it is among the most expensive pharmaceuticals in the world, with a price of US$440,000 per person per year. Eculizumab is a humanized monoclonal antibody that acts as a terminal complement inhibitor. The U.S. Food and Drug Administration (FDA) has issued a black-box warning for eculizumab whose recipients have a 1,000 to 2,000-fold greater risk of invasive meningococcal disease compared to the general U.S. population. Patients for whom eculizumab is prescribed are strongly advised by the FDA to receive meningococcal vaccination at least two weeks prior to starting therapy and to consider antimicrobial prophylaxis for the duration of treatment with eculizumab.
It is unclear if screening pregnant women for iron-deficiency anemia during pregnancy improves outcomes in the United States. The same holds true for screening children who are "6 to 24 months" old.
The goals of therapy are to control symptoms, improve quality of life, improve overall survival, and decrease progression to AML.
The IPSS scoring system can help triage patients for more aggressive treatment (i.e. bone marrow transplant) as well as help determine the best timing of this therapy. Supportive care with blood products and hematopoietic growth factors (e.g. erythropoietin) is the mainstay of therapy. The regulatory environment for the use of erythropoietins is evolving, according to a recent US Medicare National coverage determination. No comment on the use of hematopoeitic growth factors for MDS was made in that document though.
Three agents have been approved by the FDA for the treatment of MDS:
1. 5-azacytidine: 21-month median survival
2. Decitabine: Complete response rate reported as high as 43%. A phase I study has shown efficacy in AML when decitabine is combined with valproic acid.
3. Lenalidomide: Effective in reducing red blood cell transfusion requirement in patients with the chromosome 5q deletion subtype of MDS
Chemotherapy with the hypomethylating agents 5-azacytidine and decitabine has been shown to decrease blood transfusion requirements and to retard the progression of MDS to AML. Lenalidomide was approved by the FDA in December 2005 only for use in the 5q- syndrome. In the United States, treatment of MDS with lenalidomide costs about $9,200 per month.
Stem cell transplantation, particularly in younger (i.e. less than 40 years of age) and more severely affected patients, offers the potential for curative therapy. Success of bone marrow transplantation has been found to correlate with severity of MDS as determined by the IPSS score, with patients having a more favorable IPSS score tending to have a more favorable outcome with transplantation.
Iron overload can develop in MDS as a result of the RBC transfusions which are a major part of the supportive care for anemic MDS patients. Although the specific therapies patients receive may alleviate the RBC transfusion need in some cases, many MDS patients may not respond to these treatments, thus may develop iron overload from repeated RBC transfusions.
Patients requiring relatively large numbers of RBC transfusions can experience the adverse effect of chronic iron overload on their liver, heart, and endocrine functions. The resulting organ dysfunction from transfusional iron overload might be a contributor to increased illness and death in early-stage MDS.
For patients requiring many RBC transfusions, serum ferritin levels, number of RBC transfusions received, and associated organ dysfunction (heart, liver, and pancreas) should be monitored to determine iron levels. Monitoring serum ferritin may also be useful, aiming to decrease ferritin levels to .
Currently, two iron chelators are available in the US, deferoxamine for intravenous use and deferasirox for oral use. These options now provide potentially useful drugs for treating this iron overload problem. A third chelating agent is available in Europe, deferiprone for oral use, but not available in the US.
Clinical trials in the MDS are ongoing with iron chelating agents to address the question of whether iron chelation alters the natural history of patients with MDS who are transfusion dependent. Reversal of some of the consequences of iron overload in MDS by iron chelation therapy have been shown.
Both the MDS Foundation and the National Comprehensive Cancer Network MDS Guidelines Panel have recommended that chelation therapy be considered to decrease iron overload in selected MDS patients. Evidence also suggests a potential value exists to iron chelation in patients who will undergo a stem cell transplant.
Although deferasirox is generally well tolerated (other than episodes of gastrointestinal distress and kidney dysfunction in some patients), recently a safety warning by the FDA and Novartis was added to deferasirox treatment guidelines. Following postmarketing use of deferasirox, rare cases of acute kidney failure or liver failure occurred, some resulting in death. Due to this, patients should be closely monitored on deferasirox therapy prior to the start of therapy and regularly thereafter.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
Blood transfusion is sometimes used to treat iron deficiency with hemodynamic instability. Sometimes transfusions are considered for people who have chronic iron deficiency or who will soon go to surgery, but even if such people have low hemoglobin, they should be given oral treatment or intravenous iron.