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The American College of Obstetricians and Gynecologists recommends all people thinking of becoming pregnant be tested to see if they have thalassemia. Genetic counseling and genetic testing are recommended for families who carry a thalassemia trait.
A screening policy exists in Cyprus to reduce the rate of thalassemia, which, since the program's implementation in the 1970s (which also includes prenatal screening and abortion), has reduced the number of children born with the disease from one of every 158 births to almost zero.
In Iran as a premarital screening, the man's red cell indices are checked first, if he has microcytosis (mean cell hemoglobin < 27 pg or mean red cell volume < 80 fl), the woman is tested. When both are microcytic, their hemoglobin A2 concentrations are measured. If both have a concentration above 3.5% (diagnostic of thalassemia trait) they are referred to the local designated health post for genetic counseling.
Large scale awareness campaigns are being organized in India both by government and non-government organizations in favor of voluntary premarital screening to detect carriers of thalassemia and marriage between both carriers are strongly discouraged.
Mild thalassemia: people with thalassemia traits do not require medical or follow-up care after the initial diagnosis is made. People with β-thalassemia trait should be warned that their condition can be misdiagnosed as the more common iron deficiency anemia. They should avoid routine use of iron supplements; iron deficiency can develop, though, during pregnancy or from chronic bleeding. Counseling is indicated in all persons with genetic disorders, especially when the family is at risk of a severe form of disease that may be prevented.
Beta thalassemia is a hereditary disease allowing for a preventative treatment by carrier screening and prenatal diagnosis. It can be prevented if one parent has normal genes, giving rise to screenings that empower carriers to select partners with normal hemoglobin. A study aimed at detecting the genes that could give rise to offspring with sickle cell disease. Patients diagnosed with beta thalassemia have MCH ≤ 26 pg and an RDW < 19. Of 10,148 patients, 1,739 patients had a hemoglobin phenotype and RDW consistent with beta thalassemia. After the narrowing of patients, the HbA2 levels were tested presenting 77 patients with beta thalassemia. This screening procedure proved insensitive in populations of West African ancestry because of the indicators has high prevalence of alpha thalassemia. Countries have programs distributing information about the reproductive risks associated with carriers of haemoglobinopathies. Thalassemia carrier screening programs have educational programs in schools, armed forces, and through mass media as well as providing counseling to carriers and carrier couples. Screening has showed reduced incidence; by 1995 the prevalence in Italy reduced from 1:250 to 1:4000, and a 95% decrease in that region. The decrease in incidence has benefitted those affected with thalassemia, as the demand for blood has decreased, therefore improving the supply of treatment.
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.
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.
In terms of epidemiology, worldwide distribution of inherited alpha-thalassemia corresponds to areas of malaria exposure, suggesting a protective role. Thus, alpha-thalassemia is common in sub-Saharan Africa, the Mediterranean Basin, and generally tropical (and subtropical) regions. The epidemiology of alpha-thalassemia in the US reflects this global distribution pattern. More specifically, HbH disease is seen in Southeast Asia and the Middle East, while Hb Bart hydrops fetalis is acknowledged in Southeast Asia only.
The data indicate that 15% of the Greek and Turkish Cypriots are carriers of beta-thalassaemia genes, while 10% of the population carry alpha-thalassaemia genes.
Individuals heterozygous for the Hb Lepore request no particular treatment. There is no anemia or, if there is, it is very mild.
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.
There was a study on a three year old that was a carrier of the hemoglobin variant of Hopkins-2. The child had mild anemia and reticulocytosis, which is commonly seen in anemia. There were, however, no sickled cells found in the blood and they had no symptoms relating to sickle cell. There was also a reduced mean corpuscular volume (MCV), which is the average volume of red blood cell count.
There were five carriers of Hemoglobin Hopkins 2 in the Fuller-Carr family and ten double heterozygotes of Ho-2 and Hemoglobin S. All the carriers were in good health and had normal hematology test results. Out of those carrying hemoglobin S and Ho-2, none were anemic; but, a few of those studied displayed elevated reticulocyte counts. This is measured through a blood test that analyzes the speed of production of red blood cells by bone marrow and its release into the blood. There was no suggestion of symptomatic sickle cell anemia in the family.
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.
The serum iron and total iron-binding capacity (transferrin) are helpful but not diagnostic; it is quiet possible to have co-existing ineffective iron utilisation and iron deficiency, as determined by bone marrow iron status, e.g. in rheumatoid arthritis.
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.
1- Aids to clinical haematology (eds; Child J.A. and Cuthbert A.C..
It is most common in certain European populations (such as the Irish and Norwegians) and occurs in 0.6% of the population. Men with the disease are 24 times more likely to experience symptoms than affected women.
Hemoglobin Constant Spring is a variant of Hemoglobin in which a mutation in the alpha globin gene produces an alpha globin chain that is abnormally long. It is the most common nondeletional alpha-thalassemia mutation associated with hemoglobin H disease. The quantity of hemoglobin in the cells is low because the messenger RNA is unstable and some is degraded prior to protein synthesis. Another reason is that the Constant Spring alpha chain protein is itself unstable. The result is a thalassemic phenotype.
Hemoglobin Constant Spring is renamed after Constant Spring district in Jamaica.
Hemoglobin J is an abnormal hemoglobin, an alpha globin gene variant and present in various geographic locations. It was first reported in a black American family in 1956. Later on reported from Indonsia, India, and other parts of the world. Hemoglobin J reported from Meerut India shows the mutation of 120th Alanine to Glutamic acid on alpha chain. Hemoglobin J was also reported from Chhattisgarh, Central India as revealed by Lingojwar and coworkers in 2016.
Platelet storage pool deficiency has no treatment however management consists of antifibrinolytic medications if the individual has unusual bleeding event, additionally caution should be taken with usage of NSAIDS
Hemoglobin H disease is a type of alpha thalassemia caused by impaired production of three of the four alpha globins, coded by genes HBA1 and HBA2.
There is no cure for congenital alpha-mannosidosis. Treatment is limited to reducing or controlling the symptoms of this disorder by, for example, taking medication to control seizures, using a hearing aid to assist with hearing loss, and by having routine physical therapy to assist with muscular pain and weakness. In some cases, a wheelchair is recommended if muscle or spinal impairments immobilize the individual affected. Despite early reports to the contrary, bone marrow transplants performed at an early age have shown promise in halting the progression of this disorder.
The life expectancy in alpha-mannosidosis is highly variable. Individuals with early onset severe disease often do not survive beyond childhood, whereas those with milder disorders may survive well into adult life.
No cures for lysosomal storage diseases are known, and treatment is mostly symptomatic, although bone marrow transplantation and enzyme replacement therapy (ERT) have been tried with some success. ERT can minimize symptoms and prevent permanent damage to the body. In addition, umbilical cord blood transplantation is being performed at specialized centers for a number of these diseases. In addition, substrate reduction therapy, a method used to decrease the production of storage material, is currently being evaluated for some of these diseases. Furthermore, chaperone therapy, a technique used to stabilize the defective enzymes produced by patients, is being examined for certain of these disorders. The experimental technique of gene therapy may offer cures in the future.
Ambroxol has recently been shown to increase activity of the lysosomal enzyme glucocerebrosidase, so it may be a useful therapeutic agent for both Gaucher disease and Parkinson's disease. Ambroxol triggers the secretion of lysosomes from cells by inducing a pH-dependent calcium release from acidic calcium stores. Hence, relieving the cell from accumulating degradation products is a proposed mechanism by which this drug may help.
Infants with Schindler disease tend to die within 4 years of birth, therefore, treatment for this form of the disease is mostly palliative. However, Type II Schindler disease, with its late onset of symptoms, is not characterized by neurological degeneration. There is no known cure for Schindler disease, but bone marrow transplants have been trialed, as they have been successful in curing other glycoprotein disorders.
Mannosidosis is a deficiency in mannosidase, an enzyme.
There are two types:
- Alpha-mannosidosis
- Beta-mannosidosis
People with lung disease due to A1AD may receive intravenous infusions of alpha-1 antitrypsin, derived from donated human plasma. This augmentation therapy is thought to arrest the course of the disease and halt any further damage to the lungs. Long-term studies of the effectiveness of A1AT replacement therapy are not available. It is currently recommended that patients begin augmentation therapy only after the onset of emphysema symptoms.
As of 2015 there are four IV augmentation therapy manufacturers in the United States, Canada, and several European countries. Intravenous (IV) therapies are the standard mode of augmentation therapy delivery. Researchers are exploring inhaled therapies. IV augmentation therapies are manufactured by the following companies and have been shown to be clinically identical to one another in terms of dosage and efficacy.
Augmentation therapy is not appropriate for people with liver disease; treatment of A1AD-related liver damage focuses on alleviating the symptoms of the disease. In severe cases, liver transplantation may be necessary.