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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).
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.
In medicine, hemoglobinuria or haemoglobinuria is a condition in which the oxygen transport protein hemoglobin is found in abnormally high concentrations in the urine. The condition is often associated with any hemolytic anemia with primarily intravascular hemolysis, in which red blood cells (RBCs) are destroyed, thereby releasing free hemoglobin into the plasma. Excess hemoglobin is filtered by the kidneys, which excrete it into the urine, giving urine a purple color. Hemoglobinuria can lead to acute tubular necrosis which is an uncommon cause of a death of uni-traumatic patients recovering in the ICU .
The diagnosis is often made based on the medical history, blood samples, and a urine sample. The absence of urine RBCs and RBC casts microscopically despite a positive dipstick test suggests hemoglobinuria or myoglobinuria. The medical term for RBCs in the urine is hematuria.
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.
The effect of antibiotics in "E. coli" O157:H7 colitis is controversial. Certain antibiotics may stimulate further verotoxin production and thereby increase the risk of HUS. However, there is also tentative evidence that some antibiotics like quinolones may decrease the risk of hemolytic uremic syndrome. In the 1990s a group of pediatricians from the University of Washington used a network of 47 cooperating laboratories in Washington, Oregon, Idaho, and Wyoming to prospectively identify 73 children younger than 10 years of age who had diarrhea caused by "E. coli" O157:H7 The hemolytic–uremic syndrome developed in 5 of the 9 children given antibiotics (56 percent), and in 5 of the 62 children who were not given antibiotics (8 percent, P<0.001).
Treatment of HUS is generally supportive, with dialysis as needed. Platelet transfusion may actually worsen the outcome.
In most children with postdiarrheal HUS, there is a good chance of spontaneous resolution, so observation in a hospital is often all that is necessary, with supportive care such as hemodialysis where indicated. If a diagnosis of STEC-HUS is confirmed, plasmapheresis (plasma exchange) is contraindicated. However, plasmapheresis may be indicated when there is diagnostic uncertainty between HUS and TTP.
There are case reports of experimental treatments with eculizumab, a monoclonal antibody against CD5 that blocks part of the complement system, being used to treat congenital atypical hemolytic uremic syndrome, as well as severe shiga-toxin associated hemolytic uremic syndrome. These have shown promising results. Eculizeumab was approved by the U.S. Food and Drug Administration (FDA) on March 13, 2007 for the treatment of paroxysmal nocturnal hemoglobinuria (PNH), a rare, progressive, and sometimes life-threatening disease characterized by excessive hemolysis; and on September 23, 2011 for the treatment of atypical hemolytic uremic syndrome (aHUS) It was approved by the European Medicines Agency for the treatment of PNH on June 20, 2007, and on November 29, 2011 for the treatment of aHUS. However, of note is the exceedingly high cost of treatment, with one year of the drug costing over $500,000.
Scientists are trying to understand how useful it would be to immunize humans or cattles with vaccines.
Repetitive impacts to the body may cause mechanical trauma and bursting (hemolysis) of red blood cells. This has been documented to have occurred in the feet during running and hands from Conga or Candombe drumming. Defects in red blood cell membrane proteins have been identified in some of these patients. Free haemoglobin is released from lysed red blood cells and filtered into the urine.
Treat the underlying cause
Blood transfusion (PRBC) according to need
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).
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).
The treatment is antimalarial chemotherapy, intravenous fluid and sometimes supportive care such as intensive care and dialysis.
Mechanical hemolytic anemia is a form of hemolytic anemia due to mechanically induced damage to red blood cells. Red blood cells, while flexible, may in some circumstances succumb to physical shear and compression. This may result in hemoglobinuria. The damage is induced through repetitive mechanical motions such as prolonged marching ("march hemoglobinuria") and marathon running. Mechanical damage can also be induced through the chronic condition microangiopathic hemolytic anemia or due to prosthetic heart valves.
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.
Acute renal failure occurs in 55–70% of patients with STEC-HUS, although up to 70–85% recover renal function. Patients with aHUS generally have poor outcomes, with up to 50% progressing to ESRD or irreversible brain damage; as many as 25% die during the acute phase. However, with aggressive treatment, more than 90% of patients survive the acute phase of HUS, and only about 9% may develop ESRD. Roughly one-third of persons with HUS have abnormal kidney function many years later, and a few require long-term dialysis. Another 8% of persons with HUS have other lifelong complications, such as high blood pressure, seizures, blindness, paralysis, and the effects of having part of their colon removed. The overall mortality rate from HUS is 5–15%. Children and the elderly have a worse prognosis.
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.
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.
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.
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.
Treatment of thrombotic thrombocytopenic purpura (TTP) is a medical emergency, since the associated hemolytic anemia and platelet activation can lead to renal failure and changes in the level of consciousness. Treatment of TTP was revolutionized in the 1980s with the application of plasmapheresis. According to the Furlan-Tsai hypothesis, this treatment works by removing antibodies against the von Willebrand factor-cleaving protease ADAMTS-13. The plasmapheresis procedure also adds active ADAMTS-13 protease proteins to the patient, restoring a normal level of von Willebrand factor multimers. Patients with persistent antibodies against ADAMTS-13 do not always manifest TTP, and these antibodies alone are not sufficient to explain how plasmapheresis treats TTP.
People with PCH are sometimes advised to avoid exposure to cold temperatures. If anemia is severe, blood transfusion may be needed. Careful compatibility testing by the blood bank is necessary because autoantibodies may interfere with blood typing. Prednisone may be used in individuals with PCH and severe anemia.
Acute PCH tends to be transient and self-limited, particularly in children. Chronic PCH associated with syphilis resolves after the syphilis is treated with appropriate antibiotics. Chronic idiopathic PCH is usually mild.
The cause of hemolytic crises in this disease is unknown (mainly due to intravascular haemolysis). There is rapid and massive destruction of red blood cells resulting in hemoglobinemia (hemoglobin in the blood, but outside the red blood cells), hemoglobinuria (hemoglobin in urine), intense jaundice, anuria (passing less than 50 milliliters of urine in a day), and finally death in the majority of cases.
The most probable explanation for blackwater fever is an autoimmune reaction apparently caused by the interaction of the malaria parasite and the use of quinine. Blackwater fever is caused by heavy parasitization of red blood cells with "Plasmodium falciparum". There has been at least one case, however, attributed to "Plasmodium vivax".
Blackwater fever is a serious complication of malaria, but cerebral malaria has a higher mortality rate. Blackwater fever is much less common today than it was before 1950. It may be that quinine plays a role in triggering the condition, and this drug is no longer commonly used for malaria prophylaxis. Quinine remains important for treatment of malaria.
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.
Corticosteroids and immunoglobulins are two commonly used treatments for warm antibody AIHA. Initial medical treatment consists of prednisone. If ineffective, splenectomy should be considered.
If refractory to both these therapies, other options include rituximab, danazol, cyclosphosphamide, azathioprine, or ciclosporin.
High-dose intravenous immune globulin may be effective in controlling hemolysis, but the benefit is short lived (1–4 weeks), and the therapy is very expensive.