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In general, AIHA in children has a good prognosis and is self-limiting. However, if it presents within the first two years of life or in the teenage years, the disease often follows a more chronic course, requiring long-term immunosuppression, with serious developmental consequences. The aim of therapy may sometimes be to lower the use of steroids in the control of the disease. In this case, splenectomy may be considered, as well as other immunosuppressive drugs. Infection is a serious concern in patients on long-term immunosuppressant therapy, especially in very young children (less than two years).
Much literature exists regarding the treatment of AIHA. Efficacy of treatment depends on the correct diagnosis of either warm- or cold-type AIHA.
Warm-type AIHA is usually a more insidious disease, not treatable by simply removing the underlying cause. Corticosteroids are first-line therapy. For those who fail to respond or have recurrent disease, splenectomy may be considered. Other options for recurrent or relapsed disease include immunosuppressants such as rituximab, danazol, cyclophosphamide, azathioprine, or cyclosporine.
Cold agglutinin disease is treated with avoidance of cold exposure. Patients with more severe disease (symptomatic anemia, transfusion dependence) may be treated with rituximab. Steroids and splenectomy are less efficacious in cold agglutinin disease.
Paroxysmal cold hemoglobinuria is treated by removing the underlying cause, such as infection.
After birth, treatment depends on the severity of the condition, but could include temperature stabilization and monitoring, phototherapy, transfusion with compatible packed red blood, exchange transfusion with a blood type compatible with both the infant and the mother, sodium bicarbonate for correction of acidosis and/or assisted ventilation.
- Phototherapy - Phototherapy is used for cord bilirubin of 3 or higher. Some doctors use it at lower levels while awaiting lab results.
- IVIG - IVIG has been used to successfully treat many cases of HDN. It has been used not only on anti-D, but on anti-E as well. IVIG can be used to reduce the need for exchange transfusion and to shorten the length of phototherapy. The AAP recommends "In isoimmune hemolytic disease, administration of intravenousγ-globulin (0.5-1 g/kg over 2 hours) is recommended if the TSB is rising despite intensive phototherapy or the TSB level is within 2 to 3 mg/dL (34-51 μmol/L) of the exchange level . If necessary, this dose can be repeated in 12 hours (evidence quality B: benefits exceed harms). Intravenous γ-globulin has been shown to reduce the need for exchange transfusions in Rh and ABO hemolytic disease."
- Exchange transfusion - Exchange transfusion is used when bilirubin reaches either the high or medium risk lines on the nonogram provided by the American Academy of Pediatrics (Figure 4). Cord bilirubin >4 is also indicative of the need for exchange transfusion.
Bone marrow/stem cell transplants are the only known cures for this genetic disease. Frequent platelet transfusions are required to keep the patient from bleeding to death before the transplant can be performed, although this is not always the case.
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.
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.
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.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
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.
In some cases, the direct coombs will be negative but severe, even fatal HDN can occur. An indirect coombs needs to be run in cases of anti-C, anti-c, and anti-M. Anti-M also recommends antigen testing to rule out the presence of HDN.
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.
A hematologist-oncologist working in collaboration with a blood banker is helpful in complicated cases of cold agglutinin disease.
Careful planning and coordination with multiple personnel are needed if patients are to undergo a procedure during which their body temperature could fall.
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.
Patients with cold agglutinin disease should include good sources of folic acid, such as fresh fruits and vegetables, in their diet. Activities for these individuals should be less strenuous than those for healthy people, particularly for patients with anemia. Jogging in the cold could be very hazardous because of the added windchill factor.
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.
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).
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.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
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.
Basically classified by causative mechanism, types of congenital hemolytic anemia include:
- Genetic conditions of RBC Membrane
- Hereditary spherocytosis
- Hereditary elliptocytosis
- Genetic conditions of RBC metabolism (enzyme defects). This group is sometimes called "congenital nonspherocytic (hemolytic) anemia", which is a term for a congenital hemolytic anemia without spherocytosis, and usually excluding hemoglobin abnormalities as well, but rather encompassing defects of glycolysis in the erythrocyte.
- Glucose-6-phosphate dehydrogenase deficiency (G6PD or favism)
- Pyruvate kinase deficiency
- Aldolase A deficiency
- Hemoglobinopathies/genetic conditions of hemoglobin
- Sickle cell anemia
- Congenital dyserythropoietic anemia
- Thalassemia
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.
PNH is rare, with an annual rate of 1-2 cases per million. The prognosis without disease-modifying treatment is 10–20 years. Many cases develop in people who have previously been diagnosed with aplastic anemia or myelodysplastic syndrome. The fact that PNH develops in MDS also explains why there appears to be a higher rate of leukemia in PNH, as MDS can sometimes transform into leukemia.
25% of female cases of PNH are discovered during pregnancy. This group has a high rate of thrombosis, and the risk of death of both mother and child are significantly increased (20% and 8% respectively).
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.
Acquired hemolytic anemia can be divided into immune and non-immune mediated forms of hemolytic anemia.
Sublingual treatments have also been postulated to be more effective than oral treatments alone. A 2003 study found, while this method is effective, a dose of 500 μg of cyanocobalamin given either orally or sublingually, is equally efficacious in restoring normal physiological concentrations of cobalamin. Intranasal methods have also been studied as a vehicle for the delivery of cobalamin. A 1997 study monitored the plasma cobalamin concentration of six patients with pernicious anemia over a period of 35 days while being treated with 1500 μg of intranasal hydroxocobalamin. One hour after administration, all patients showed on average an immediate eight-fold increase in plasma cobalamin concentration and a two-fold increase after 35 days with three 1500 μg treatments. However, further studies are needed to investigate the long-term effectiveness of this delivery method.