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Ted DeVita died of transfusional iron overload from too many blood transfusions.
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.
Hemosiderosis (AmE) or haemosiderosis (BrE) is a form of iron overload disorder resulting in the accumulation of hemosiderin.
Types include:
- Transfusion hemosiderosis
- Idiopathic pulmonary hemosiderosis
- Transfusional diabetes
Hemosiderin deposition in the lungs is often seen after diffuse alveolar hemorrhage, which occurs in diseases such as Goodpasture's syndrome, granulomatosis with polyangiitis, and idiopathic pulmonary hemosiderosis. Mitral stenosis can also lead to pulmonary hemosiderosis. Hemosiderin collects throughout the body in hemochromatosis. Hemosiderin deposition in the liver is a common feature of hemochromatosis and is the cause of liver failure in the disease. Selective iron deposition in the beta cells of pancreatic islets leads to diabetes due to distribution of transferrin receptor on the beta cells of islets and in the skin leads to hyperpigmentation. Hemosiderin deposition in the brain is seen after bleeds from any source, including chronic subdural hemorrhage, cerebral arteriovenous malformations, cavernous hemangiomata. Hemosiderin collects in the skin and is slowly removed after bruising; hemosiderin may remain in some conditions such as stasis dermatitis. Hemosiderin in the kidneys has been associated with marked hemolysis and a rare blood disorder called paroxysmal nocturnal hemoglobinuria.
Hemosiderin may deposit in diseases associated with iron overload. These diseases are typically diseases in which chronic blood loss requires frequent blood transfusions, such as sickle cell anemia and thalassemia, though beta thalassemia minor has been associated with hemosiderin deposits in the liver in those with non-alcoholic fatty liver disease independent of any transfusions.
Treatment for hemosiderin focuses on limiting the effects of the underlying disease leading to continued deposition. In hemochromatosis, this entails frequent phlebotomy granulomatosis, immune suppression is required. Limiting blood transfusions and institution of iron chelation therapy when iron overload is detected are important when managing sickle-cell anemia and other chronic hemolytic anemias.
The thalassemia trait may confer a degree of protection against malaria, which is or was prevalent in the regions where the trait is common, thus conferring a selective survival advantage on carriers (known as heterozygous advantage), thus perpetuating the mutation. In that respect, the various thalassemias resemble another genetic disorder affecting hemoglobin, sickle-cell disease.
The disorder affects all genders but is more prevalent in certain ethnicities and age groups. 20 people die per year causing thalassemia to be listed as a “rare disease”. In the United States, thalassemia’s prevalence is approximately 1 in 272,000 or 1,000 people. There have been 4,000 hospitalized cases in England in 2002 and 9,233 consultant episodes for thalassemia. Men accounted for 53% of hospital consultant episodes and women accounted for 47%. The mean patient age is 23 with only 1% of consultants the patient is older than 75 and 69% were 15-59 year olds. The Children’s Hospital Oakland formed an international network to combat thalassemia. “It is the world’s most common genetic blood disorder and is rapidly increasing”. 7% of the world’s population are carriers and 400,000 babies are born with the trait annually. It is usually fatal in infancy if blood transfusion are not initiated immediately.
The highest frequency of sickle cell disease is found in tropical regions, particularly sub-Saharan Africa, tribal regions of India and the Middle-East. Migration of substantial populations from these high prevalence areas to low prevalence countries in Europe has dramatically increased in recent decades and in some European countries sickle-cell disease has now overtaken more familiar genetic conditions such as haemophilia and cystic fibrosis. In 2015, it resulted in about 114,800 deaths.
Sickle-cell disease occurs more commonly among people whose ancestors lived in tropical and sub-tropical sub-Saharan regions where malaria is or was common. Where malaria is common, carrying a single sickle-cell allele (trait) confers a selective advantage—in other words, being a heterozygote is advantageous. Specifically, humans with one of the two alleles of sickle-cell disease show less severe symptoms when infected with malaria.
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
In terms of genetics of atransferrinemia researchers have identified mutations in the TF gene as a probable cause of this genetic disorder in affected people.
Transferrin is a serum transport protein that transports iron to the reticuloendothelial system for utilization and erythropoiesis, since there is no transferrin in atransferrinemia, serum free iron cannot reach reticuloendothelial cells and there is microcytic anemia. Also, this excess iron deposits itself in the heart, liver and joints, and causes damage. Ferritin, the storage form of iron gets secreted more into the bloodstream so as to bind with the excessive free iron and hence serum ferritin levels rise in this condition
About 90% of people survive to age 20, and close to 50% survive beyond the fifth decade. In 2001, according to one study performed in Jamaica, the estimated mean survival for people with sickle-cell was 53 years old for men and 58 years old for women with homozygous SCD. The specific life expectancy in much of the developing world is unknown.
Complications of HDN could include kernicterus, hepatosplenomegaly, inspissated (thickened or dried) bile syndrome and/or greenish staining of the teeth, hemolytic anemia and damage to the liver due to excess bilirubin. Similar conditions include acquired hemolytic anemia, congenital toxoplasma and syphilis infection, congenital obstruction of the bile duct and cytomegalovirus infection.
- High at birth or rapidly rising bilirubin
- Prolonged hyperbilirubinemia
- Bilirubin Induced Neuorlogical Dysfunction
- Cerebral Palsy
- Kernicterus
- Neutropenia
- Thrombocytopenia
- Hemolytic Anemia - MUST NOT be treated with iron
- Late onset anemia - Must NOT be treated with iron. Can persist up to 12 weeks after birth.
In terms of treatment of atransferrinemia, iron supplements (oral iron therapy) are the preferred choice, one finds that RBC transfusions are very infrequently needed.
In 2003, the incidence of Rh(D) sensitization in the United States was 6.8 per 1000 live births; 0.27% of women with an Rh incompatible fetus experience alloimmunization.
Acquired hemolytic anemia can be divided into immune and non-immune mediated forms of hemolytic anemia.
Drug induced hemolysis has large clinical relevance. It occurs when drugs actively provoke red blood cell destruction. It can be divided in the following manner:
- Drug-induced autoimmune hemolytic anemia
- Drug-induced nonautoimmune hemolytic anemia
A total of four mechanisms are usually described, but there is some evidence that these mechanisms may overlap.
Iatrogenic causes of pancytopenia include chemotherapy for malignancies if the drug or drugs used cause bone marrow suppression. Rarely, drugs (antibiotics, blood pressure medication, heart medication) can cause pancytopenia.
The antibiotics Linezolid and Chloramphenicol can cause pancytopenia in some individuals.
Rarely, pancytopenia may have other causes, such as mononucleosis, or other viral diseases. Increasingly, HIV is itself a cause for pancytopenia.
- Familial hemophagocytic syndrome
- Aplastic anemia
- Gaucher's disease
- metastatic carcinoma of bone
- Multiple Myeloma
- overwhelming infections
- Lymphoma
- myelofibrosis
- Dyskeratosis congenita
- Myelodysplastic syndrome
- Leukemia
- Leishmaniasis
- Severe Folate or vitamin B12 deficiency
- Systemic lupus erythematosus
- Paroxysmal nocturnal hemoglobinuria (blood test)
- Viral infections (such as HIV, EBV--undetermined virus is most common).
- Alimentary toxic aleukia
- Copper deficiency
- Pernicious anemia
- Medication
- Hypersplenism
- Osteopetrosis
- Organic acidurias (Propionic Acidemia, Methylmalonic Aciduria, Isovaleric Aciduria)
- Low dose arsenic poisoning
- Sako disease (Myelodysplastic-cytosis)
- Chronic radiation sickness
- LIG4 syndrome
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).
Congenital dyserythropoietic anemia type IV is an autosomal dominant inherited red blood cell disorder characterized by ineffective erythropoiesis and hemolysis resulting in anemia. Circulating erythroblasts and erythroblasts in the bone marrow show various morphologic abnormalities. Affected individuals with CDAN4 also have increased levels of fetal hemoglobin.
Hemoglobin Barts, abbreviated Hb Barts, is an abnormal type of hemoglobin that consists of four gamma globins. It is moderately insoluble, and therefore accumulates in the red blood cells. It has an extremely high affinity for oxygen, resulting in almost no oxygen delivery to the tissues. As an embryo develops, it begins to produce alpha-globins at weeks 5-6 of development. When both HBA1 and HBA2, the two genes that code for alpha globins, are non-functional, only gamma globins are produced. These gamma globins bind to form hemoglobin Barts. It is produced in the disease alpha-thalassemia and in the most severe of cases, it is the only form of haemoglobin in circulation. In this situation, a fetus will develop hydrops fetalis and normally die before or shortly after birth, unless intrauterine blood transfusion is performed.
Since hemoglobin Barts is elevated in alpha thalassaemia, it can be measured, providing a useful screening test for this disease in some populations.
The ability to measure hemoglobin Barts makes it useful in newborn screening tests. If hemoglobin Barts is detected on a newborn screen, the patient is usually referred for further evaluation since detection of hemoglobin Barts can indicate either one alpha globin gene deletion, making the baby a silent alpha thalassemia carrier, two alpha globin gene deletions (alpha thalassemia), or hemoglobin H disease (three alpha globin gene deletions). Deletion of four alpha globin genes is not compatible with life.
This variant of hemoglobin is so called as it was discovered at St. Bartholomew's Hospital in London, also called St. Barts.
Haematologists have identified a number of variants. These can be classified as below.
- Overhydrated hereditary stomatocytosis
- Dehydrated HSt (hereditary xerocytosis; hereditary hyperphosphatidylcholine haemolytic anaemia)
- Dehydrated with perinatal ascites
- Cryohydrocytosis
- 'Blackburn' variant.
- Familial pseudohyperkalaemia
There are other families that do not fall neatly into any of these classifications.
Stomatocytosis is also found as a hereditary disease in Alaskan malamute and miniature schnauzer dogs.
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.
In about a third of all ABO incompatible pregnancies maternal IgG anti-A or IgG anti-B antibodies pass through the placenta to the fetal circulation leading to a weakly positive direct Coombs test for the neonate's blood. However, ABO HDN is generally mild and short-lived and only occasionally severe because:
- IgG anti-A (or IgG anti-B) antibodies that enter the fetal circulation from the mother find A (or B) antigens on many different fetal cell types, leaving fewer antibodies available for binding onto fetal red blood cells.
- Fetal RBC surface A and B antigens are not fully developed during gestation and so there are a smaller number of antigenic sites on fetal RBCs.
Hereditary stomatocytosis describes a number of inherited autosomal dominant human conditions which affect the red blood cell, in which the membrane or outer coating of the cell 'leaks' sodium and potassium ions.
Preterm infants are often anemic and typically experience heavy blood losses from frequent laboratory testing in the first few weeks of life. Although their anemia is multifactorial, repeated blood sampling and reduced erythropoiesis with extremely low serum levels of erythropoietin (EPO) are major determining factors. Blood sampling done for laboratory testing can easily remove enough blood to produce anemia. Obladen, Sachsenweger and Stahnke (1987) studied 60 very low birth weight infants during the first 28 days of life. Infants were divided into 3 groups, group 1 (no ventilator support, 24 ml/kg blood loss), group 2(minor ventilated support, 60 ml/kg blood loss), and group 3(ventilated support for respiratory distress syndrome, 67 ml/kg blood loss). Infants were checked for clinical symptoms and laboratory signs of anemia 24 hours before and after the blood transfusion. The study found that groups 2 and 3 who had significant amount of blood loss, showed poor weight gain, pallor and distended abdomen. These reactions are the most frequent symptoms of anemia.
During the first weeks of life, all infants experience a decline in circulating red blood cell (RBC) volume generally expressed as blood hemoglobin concentration (Hb). As anemia develops, there is even more of a significant reduction in the concentration of hemoglobin. Normally this stimulates a significant increased production of erythropoietin (EPO), but this response is diminished in premature infants. Dear, Gill, Newell, Richards and Schwarz (2005) conducted a study to show that there is a weak negative correlation between EPO and Hb. The researchers recruited 39 preterm infants from 10 days of age or as soon as they could manage without respiratory support. They estimated total EPO and Hb weekly and 2 days after a blood transfusion. The study found that when Hb>10, EPO mean was 20.6 and when Hb≤10, EPO mean was 26.8. As Hb goes down, EPO goes up. While the reason for this decreased response is not fully understood, Strauss (n.d.) states that it results from both physiological factors (e.g., the rapid rate of growth and need for a commensurate increase in RBC mass to accompany the increase in blood volume) and, in sick premature infants, from phlebotomy blood losses. In premature infants this decline occurs earlier and more pronounced that it does in healthy term infants. Healthy term infants Hb rarely falls below 9 g/dL at an age of approximately 10–12 weeks, while in premature infants, even in those without complicating illnesses, the mean Hb falls to approximately 8g/dL in infants of 1.0-1.5 kg birth weight and to 7g/dL in infants <1.0 kg. Because this postnatal drop in hemoglobin level is universal and is well tolerated in term infants, it is commonly referred to as the “physiologic” anemia of infancy. However, in premature infants the decline in Hb may be associated with abnormal clinical signs severe enough to prompt transfusions.
Anti-A and anti-B antibodies are usually IgM and do not pass through the placenta, but some mothers "naturally" have IgG anti-A or IgG anti-B antibodies, which can pass through the placenta. Exposure to A-antigens and B-antigens, which are both widespread in nature, usually leads to the production of IgM anti-A and IgM anti-B antibodies but occasionally IgG antibodies are produced.
Some mothers may be sensitized by fetal-maternal transfusion of ABO incompatible red blood and produce immune IgG antibodies against the antigen they do not have and their baby does. For example, when a mother of genotype OO (blood group O) carries a fetus of genotype AO (blood group A) she may produce IgG anti-A antibodies. The father will either have blood group A, with genotype AA or AO, or more rarely, have blood group AB, with genotype AB.
It would be very rare for ABO sensitization to be caused by therapeutic blood transfusion as a great deal of effort and checking is done to ensure that blood is ABO compatible between the recipient and the donor.
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.