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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.
Treating immune-mediated aplastic anemia involves suppression of the immune system, an effect achieved by daily medicine intake, or, in more severe cases, a bone marrow transplant, a potential cure. The transplanted bone marrow replaces the failing bone marrow cells with new ones from a matching donor. The multipotent stem cells in the bone marrow reconstitute all three blood cell lines, giving the patient a new immune system, red blood cells, and platelets. However, besides the risk of graft failure, there is also a risk that the newly created white blood cells may attack the rest of the body ("graft-versus-host disease"). In young patients with an HLA matched sibling donor, bone marrow transplant can be considered as first-line treatment, patients lacking a matched sibling donor typically pursue immunosuppression as a first-line treatment, and matched unrelated donor transplants are considered a second-line therapy.
Medical therapy of aplastic anemia often includes a course of antithymocyte globulin (ATG) and several months of treatment with ciclosporin to modulate the immune system. Chemotherapy with agents such as cyclophosphamide may also be effective but has more toxicity than ATG. Antibody therapy, such as ATG, targets T-cells, which are believed to attack the bone marrow. Corticosteroids are generally ineffective, though they are used to ameliorate serum sickness caused by ATG. Normally, success is judged by bone marrow biopsy 6 months after initial treatment with ATG.
One prospective study involving cyclophosphamide was terminated early due to a high incidence of mortality, due to severe infections as a result of prolonged neutropenia.
In the past, before the above treatments became available, patients with low leukocyte counts were often confined to a sterile room or bubble (to reduce risk of infections), as in the case of Ted DeVita.
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.
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).
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.
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.
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.
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.
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.
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.
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.
One exploratory, and potential alternative method for the treatment of pernicious anemia is the use of transdermal patches. In one such system, the patches are composed of cyanocobalamin, its stabilizers, and epidermal penetration enhancers. The transdermal route allows the cobalamin derivative to passively diffuse through the stratum corneum, epidermis, and dermis, and ultimately entering the bloodstream; hence, the cobalamin avoids the hepatic first pass effect, and so offers the potential for improved bioavailability and efficacy. Slow release increases cobalamin half-life, offering the potential of decreases in required dosage required relative to oral delivery methods. In one such system, a drug-loaded polycaprolactone fiber that is prepared as a electrospun nanofiber can release hundreds of micrograms of cobabalmin per day.
Treatment with high-dose vitamin B by mouth also appears effective.
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.
Untreated, severe aplastic anemia has a high risk of death. Modern treatment, by drugs or stem cell transplant, has a five-year survival rate that exceeds 85%, with younger age associated with higher survival.
Survival rates for stem cell transplant vary depending on age and availability of a well-matched donor. Five-year survival rates for patients who receive transplants have been shown to be 82% for patients under age 20, 72% for those 20–40 years old, and closer to 50% for patients over age 40. Success rates are better for patients who have donors that are matched siblings and worse for patients who receive their marrow from unrelated donors.
Older people (who are generally too frail to undergo bone marrow transplants), and people who are unable to find a good bone marrow match, undergoing immune suppression have five-year survival rates of up to 75%.
Relapses are common. Relapse following ATG/ciclosporin use can sometimes be treated with a repeated course of therapy. In addition, 10-15% of severe aplastic anemia cases evolve into MDS and leukemia. According to a study, for children who underwent immunosuppressive therapy, about 15.9% of children who responded to immunosuppressive therapy encountered relapse.
Milder disease can resolve on its own.
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.
Discontinuation of heparin is critical in a case of heparin-induced thrombocytopenia (HIT). Beyond that, however, clinicians generally treat to avoid a thrombosis, often by starting patients directly on warfarin. For this reason, patients are usually treated with a direct thrombin inhibitor, such as lepirudin or argatroban, which are approved by the FDA for this use. Other blood thinners sometimes used in this setting that are not FDA-approved for treatment of HIT include bivalirudin and fondaparinux. Platelet transfusions are not routinely used to treat HIT because thrombosis, not bleeding, is the primary problem.
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 is guided by the severity and specific cause of the disease. Treatment focuses on eliminating the underlying problem, whether that means discontinuing drugs suspected to cause it or treating underlying sepsis. Diagnosis and treatment of serious thrombocytopenia is usually directed by a hematologist. Corticosteroids may be used to increase platelet production. Lithium carbonate or folate may also be used to stimulate platelet production in the bone marrow.
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.
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.
Congenital hemolytic anemia (or hereditary hemolytic anemia) refers to hemolytic anemia which is primarily due to congenital disorders.
Acquired hemolytic anemia may be caused by immune-mediated causes, drugs and other miscellaneous causes.
- Immune-mediated causes could include transient factors as in "Mycoplasma pneumoniae" infection (cold agglutinin disease) or permanent factors as in autoimmune diseases like autoimmune hemolytic anemia (itself more common in diseases such as systemic lupus erythematosus, rheumatoid arthritis, Hodgkin's lymphoma, and chronic lymphocytic leukemia).
- Spur cell hemolytic anemia
- Any of the causes of hypersplenism (increased activity of the spleen), such as portal hypertension.
- Acquired hemolytic anemia is also encountered in burns and as a result of certain infections (e.g. malaria).
- Lead poisoning resulting from the environment causes non-immune hemolytic anemia.
- Runners can suffer hemolytic anemia due to "footstrike hemolysis", owing to the destruction of red blood cells in feet at foot impact.
- Low-grade hemolytic anemia occurs in 70% of prosthetic heart valve recipients, and severe hemolytic anemia occurs in 3%.