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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.
People with severe thalassemia require medical treatment. A blood transfusion regimen was the first measure effective in prolonging life.
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.
Affected children require regular lifelong blood transfusion and can have complications, which may involve the spleen. Bone marrow transplants can be curative for some children. Patients receive frequent blood transfusions that lead to or potentiate iron overload. Iron chelation treatment is necessary to prevent damage to internal organs. Advances in iron chelation treatments allow patients with thalassemia major to live long lives with access to proper treatment. Popular chelators include deferoxamine and deferiprone.
The most common patient deferoxamine complaint is that they are painful and inconvenient. The oral chelator deferasirox was approved for use in 2005 in some countries, it offers some hope with compliance at a higher cost. Bone marrow transplantation is the only cure and is indicated for patients with severe thalassemia major. Transplantation can eliminate a patient's dependence on transfusions. Absent a matching donor, a savior sibling can be conceived by preimplantation genetic diagnosis (PGD) to be free of the disease as well as to match the recipient's human leukocyte antigen (HLA) type.
Scientists at Weill Cornell Medical College have developed a gene therapy strategy that could feasibly treat both beta-thalassemia and sickle cell disease. The technology is based on delivery of a lentiviral vector carrying both the human β-globin gene and an ankyrin insulator to improve gene transcription and translation, and boost levels of β-globin production.
Most people with sickle-cell disease have intensely painful episodes called vaso-occlusive crises. However, the frequency, severity, and duration of these crises vary tremendously. Painful crises are treated symptomatically with pain medications; pain management requires opioid administration at regular intervals until the crisis has settled. For milder crises, a subgroup of patients manage on NSAIDs (such as diclofenac or naproxen). For more severe crises, most patients require inpatient management for intravenous opioids; patient-controlled analgesia (PCA) devices are commonly used in this setting. Diphenhydramine is also an effective agent that doctors frequently prescribe to help control itching associated with the use of opioids.
Treatment is the same as for patients with sickle cell disease. Patients may receive hydroxyurea to induce the protective effects of increased fetal hemoglobin production. They may also benefit from blood transfusions especially during vaso-occlusive crises. Patients may be offered chemoprophylaxis with penicillin. They may have splenic dysfunction and splenectomy is frequently performed. Vaccination against encapsulated bacteria including Streptococcus pneumoniae is recommended.
Management is similar to vaso-occlusive crisis, with the addition of antibiotics (usually a quinolone or macrolide, since cell wall-deficient ["atypical"] bacteria are thought to contribute to the syndrome), oxygen supplementation for hypoxia, and close observation. Should the pulmonary infiltrate worsen or the oxygen requirements increase, simple blood transfusion or exchange transfusion is indicated. The latter involves the exchange of a significant portion of the person's red cell mass for normal red cells, which decreases the percent of haemoglobin S in the patient's blood. The patient with suspected acute chest syndrome should be admitted to the hospital with worsening A-a gradient an indication for ICU admission.
Usually no treatment is needed. Folic acid supplementation may help produce normal red blood cells and improve the symptoms of anemia
Treatment for alpha-thalassemia may consist of blood transfusions, and possible splenectomy; additionally, gallstones may be a problem that would require surgery. Secondary complications from febrile episode should be monitored, and most individuals live without any need for treatment
Additionally, stem cell transplantation should be considered as a treatment (and cure), which is best done in early age. Other options, such as gene therapy, are still being developed.
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
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.
Individuals heterozygous for the Hb Lepore request no particular treatment. There is no anemia or, if there is, it is very mild.
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.
Genetic counseling may be appropriate for high-risk couples who wish to have a baby.
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.
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.
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.
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.
A potential complication that may occur in children that suffer acute anemia with a hemoglobin count below 5.5 g/dl is silent stroke A silent stroke is a type of stroke that does not have any outward symptoms (asymptomatic), and the patient is typically unaware they have suffered a stroke. Despite not causing identifiable symptoms a silent stroke still causes damage to the brain, and places the patient at increased risk for both transient ischemic attack and major stroke in the future.
Because of the microcirculatory distress, a telltale sign or symptom of a potential sickling collapse is cramping. Specifically to sickle cell trait, cramping occurs in the lower extremities and back in athletes undergoing intense physical activity or exertion. In comparison to heat cramps, sickling cramps are less intense in terms of pain and have a weakness and fatigue associated with them, as opposed to tightly contracted muscles that lock up during heat cramps.
A sickling collapse comes on slowly, following cramps, weakness, general body aches and fatigue. Individuals with known positive sickle cell trait status experiencing significant muscle weakness or fatigue during exercise should take extra time to recover and hydrate before returning to activity in order to prevent further symptoms.
A collapse can be prevented by taking steps to ensure sufficient oxygen levels in the blood. Among these preventative measures are proper hydration and gradual acclimation to conditions such as heat, humidity, and decreased air pressure due to higher altitude. Gradual progression of exertion levels also helps athletes' bodies adjust and compensate, gaining fitness slowly over the course of several weeks.
Recombinant EPO (r-EPO) may be given to premature infants to stimulate red blood cell production. Brown and Keith (1999) studied two groups of 40 very low birth weight (VLBW) infants to compare the erythropoietic response between two and five times a week dosages of recombinant human erythropoietin (r-EPO) using the same dose. They established that more frequent dosing of the same weekly amount of r-EPO generated a significant and continuous increase in Hb in VLBW infants. The infants that received five dosages had 219,857 mm³ while infants that received two dosages only had 173,361 mm³. However, the response to r-EPO typically takes up to two weeks and the higher dosages lead to higher Hb. Brown and Keith (1999) study also showed responses between two dosage schedules (two times a week and five times a week). Infants were recruited for gestational age—age since conception—≤27 weeks and 28 to 30 weeks and then randomized into the two groups, each totaling 500 U/kg a week. Brown and Keith found that after two weeks of r-EPO administration, Hb counts had increased and leveled off; the infants who received r-EPO five times a week had significantly higher Hb counts. This was present at four weeks for all infants ≤30 weeks gestation and at 8 weeks for infants ≤27 weeks gestation.
To date, studies of r-EPO use in premature infants have had mixed results. Ohls et al. examined the use of early r-EPO plus iron and found no short-term benefits in two groups of infants (172 infants less than 1000 g and 118 infants 1000–1250 g). All r-EPO treated infants received 400 U/g three times a week until they reached 35 weeks gestational age. The use of r-EPO did not decrease the average number of transfusions in the infants born at less than 1000 g, or the percentage of infants in the 1000 to 1250 group. A multi-center European trial studied early versus late r-EPO in 219 infants with birth weights between 500 and 999 g. An r-EPO close of 750 U/kg/week was given to infants in both the early (1–9 weeks) and late (4–10 weeks) groups. The two r-EPO groups were compared to a control group who did not receive r-EPO. Infants in all three groups received 3 to 9 mg/kg of enteral iron. These investigators reported a slight decrease in transfusion and donor exposures in the early r-EPO group (1–9 weeks): 13% early, 11% late and 4% control group. It is likely that only a carefully selected subpopulation of infants may benefit from its use. Contrary to what just said, Bain and Blackburn (2004) also state in another study the use of r-EPO does not appear to have a significant effect on reducing the numbers of early transfusions in most infants, but may be useful to reduce numbers of late transfusion in extremely low-birth-weight infants. A British task force to establish transfusion guidelines for neonates and young children and to help try to explain this confusion recently concluded that “the optimal dose, timing, and nutritional support required during EPO treatment has yet to be defined and currently the routine use of EPO in this patient population is not recommended as similar reduction in blood use can probably be achieved with appropriate transfusion protocols.”
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.
Other strategies involve the reduction of blood loss during phlebotomy.
Another treatment used is therapeutic strategies. These strategies are aimed at reducing transfusions have assessed the use of strict blood transfusions guidelines and EPO therapy, but reduction of blood loss is most important. For extremely low birth weight infants, laboratory blood testing using bedside devices offers a unique opportunity to reduce blood transfusions. This practice has been referred to as point-of-care testing. Use of these kind of devices to measure the most common ordered blood tests could significantly decrease phlebotomy loss and lead to a reduction in the need for blood transfusions among critically ill premature neonates. A study was done by Adams, Benitz, Geaghan, Kumar, Madan and Widness (2005) to test this theory by conducting a retrospective chart review on all inborn infants <1000g admitted to the NICU during two separate years. Conventional bench top laboratory analysis during the first year was done using Radiometer Blood Gas and Electrolyte Analyzer. Bedside blood gas analysis during the second year was performed using a point-of-care analyzer. An estimated blood loss in the two groups was determined based on the number of specific blood tests on individual infants. The study found that there was an estimated 30% reduction in the total volume of blood removed for the blood tests. This study concluded that there is modern technology that can be used instead of blood transfusions and r-EPO.
There have been reports of pulmonary venous thromboembolism in pregnant women with sickle cell trait, or men during prolonged airflight, and mild strokes and abnormalities on PET scans in children with the trait.
Sickle cell trait appears to worsen the complications seen in diabetes mellitus type 2 (retinopathy, nephropathy and proteinuria) and provoke hyperosmolar diabetic coma nephropathy, especially in male patients.
Ted DeVita died of transfusional iron overload from too many blood transfusions.