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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.
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.
Overall, hemoglobin C disease is one of the more benign hemoglobinopathies. Mild-to-moderate reduction in RBC lifespan may accompany from mild hemolytic anemia. Individuals with hemoglobin C disease have sporadic episodes of musculoskeletal (joint) pain. People with hemoglobin C disease can expect to lead a normal life.
Usually no treatment is needed. Folic acid supplementation may help produce normal red blood cells and improve the symptoms of anemia
From birth to five years of age, penicillin daily, due to the immature immune system that makes them more prone to early childhood illnesses is recommended. Dietary supplementation of folic acid had been previously recommended by the WHO. A 2016 Cochrane review of its use found "the effect of supplementation on anaemia and any symptoms of anaemia remains unclear" due to a lack of medical evidence.
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.
The protective effect of sickle-cell trait does not apply to people with sickle cell disease; in fact, they are more vulnerable to malaria, since the most common cause of painful crises in malarial countries is infection with malaria. It has therefore been recommended that people with sickle-cell disease living in malarial countries should receive anti-malarial chemoprophylaxis for life.
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.
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.
The ideal treatment for anemia of chronic disease is to treat the chronic disease successfully, but this is rarely possible.
Parenteral iron is increasingly used for anemia in chronic renal disease and inflammatory bowel disease.
Erythropoietin can be helpful, but this is costly and may be dangerous. Erythropoietin is advised either in conjunction with adequate iron replacement which in practice is intravenous, or when IV iron has proved ineffective.
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.
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.”
Methemoglobinemia can be treated with supplemental oxygen and methylene blue 1% solution (10 mg/ml) 1 to 2 mg/kg administered intravenously slowly over five minutes. Although the response is usually rapid, the dose may be repeated in one hour if the level of methemoglobin is still high one hour after the initial infusion. Methylene Blue inhibits monoamine oxidase and serotonin toxicity can occur if taken with an SSRI (selective serotonin reuptake inhibitor) medicine.
Methylene blue restores the iron in hemoglobin to its normal (reduced) oxygen-carrying state. This is achieved by providing an artificial electron acceptor (such as methylene blue or flavin) for NADPH methemoglobin reductase (RBCs usually don't have one; the presence of methylene blue allows the enzyme to function at 5× normal levels). The NADPH is generated via the hexose monophosphate shunt.
Genetically induced chronic low-level methemoglobinemia may be treated with oral methylene blue daily. Also, vitamin C can occasionally reduce cyanosis associated with chronic methemoglobinemia but has no role in treatment of acute acquired methemoglobinemia. Diaphorase normally contributes only a small percentage of the red blood cell's reducing capacity, but can be pharmacologically activated by exogenous cofactors (such as methylene blue) to 5 times its normal level of activity.
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.
Limiting some microbes' access to iron can reduce their virulence, thereby potentially reducing the severity of infection. Blood transfusion to patients with anemia of chronic disease is associated with a higher mortality, supporting the concept.
Methemoglobinemia is a condition caused by elevated levels of methemoglobin in the blood. Methemoglobin is a form of hemoglobin that contains the ferric [Fe] form of iron. The affinity for oxygen of ferric iron is impaired. The binding of oxygen to methemoglobin results in an "increased" affinity for oxygen in the remaining heme sites that are in ferrous state within the same tetrameric hemoglobin unit. This leads to an overall reduced ability of the red blood cell to release oxygen to tissues, with the associated oxygen–hemoglobin dissociation curve therefore shifted to the left. When methemoglobin concentration is elevated in red blood cells, tissue hypoxia may occur.
Treatment is almost always aimed to control hemorrhages, treating underlying causes, and taking preventative steps before performing invasive surgeries.
Hypoprothrombinemia can be treated with periodic infusions of purified prothrombin complexes. These are typically used as treatment methods for severe bleeding cases in order to boost clotting ability and increasing levels of vitamin K-dependent coagulation factors.
1. A known treatment for hypoprothrombinemia is menadoxime.
2. Menatetrenone was also listed as a Antihaemorrhagic vitamin.
3. 4-Amino-2-methyl-1-naphthol (Vitamin K5) is another treatment for hypoprothrombinemia.
1. Vitamin K forms are administered orally or intravenously.
4. Other concentrates include Proplex T, Konyne 80, and Bebulin VH.
Fresh Frozen Plasma infusion (FFP) is a method used for continuous bleeding episodes, every 3-5 weeks for mention.
1. Used to treat various conditions related to low blood clotting factors.
2. Administered by intravenous injection and typically at a 15-20 ml/kg/dose.
3. Can be used to treat acute bleeding.
Sometimes, underlying causes cannot be controlled or determined, so management of symptoms and bleeding conditions should be priority in treatment.
Invasive options, such as surgery or clotting factor infusions, are required if previous methods do not suffice. Surgery is to be avoided, as it causes significant bleeding in patients with hypoprothrombinemia.
Prognosis for patients varies and is dependent on severity of the condition and how early the treatment is managed.
1. With proper treatment and care, most people go on to live a normal and healthy life.
2. With more severe cases, a hematologist will need to be seen throughout the patient's life in order to deal with bleeding and continued risks.
Secondary polycythemia is caused by either natural or artificial increases in the production of erythropoietin, hence an increased production of erythrocytes. In secondary polycythemia, 6 to 8 million and occasionally 9 million erythrocytes may occur per millimeter of blood. Secondary polycythemia resolves when the underlying cause is treated.
Secondary polycythemia in which the production of erythropoietin increases appropriately is called physiologic polycythemia.
Conditions which may result in a physiologically appropriate polycythemia include:
- Altitude related - This physiologic polycythemia is a normal adaptation to living at high altitudes (see altitude sickness). Many athletes train at high altitude to take advantage of this effect — a legal form of blood doping. Some individuals believe athletes with primary polycythemia may have a competitive advantage due to greater stamina. However, this has yet to be proven due to the multifaceted complications associated with this condition.
- Hypoxic disease-associated - for example in cyanotic heart disease where blood oxygen levels are reduced significantly, may also occur as a result of hypoxic lung disease such as COPD and as a result of chronic obstructive sleep apnea.
- Iatrogenic - Secondary polycythemia can be induced directly by phlebotomy (blood letting) to withdraw some blood, concentrate the erythrocytes, and return them to the body.
- Genetic - Heritable causes of secondary polycythemia also exist and are associated with abnormalities in hemoglobin oxygen release. This includes patients who have a special form of hemoglobin known as Hb Chesapeake, which has a greater inherent affinity for oxygen than normal adult hemoglobin. This reduces oxygen delivery to the kidneys, causing increased erythropoietin production and a resultant polycythemia. Hemoglobin Kempsey also produces a similar clinical picture. These conditions are relatively uncommon.
Conditions where the secondary polycythemia is not as a result of physiologic adaptation and occurs irrespective of body needs include:
- Neoplasms - Renal-cell carcinoma or liver tumors, von Hippel-Lindau disease, and endocrine abnormalities including pheochromocytoma and adrenal adenoma with Cushing's syndrome.
- People whose testosterone levels are high because of the use of anabolic steroids, including athletes who abuse steroids, or people on testosterone replacement for hypogonadism or transgender hormone replacement therapy, as well as people who take erythropoietin, may develop secondary polycythemia.
Inherited mutations in three genes which all result in increased stability of hypoxia-inducible factors, leading to increased erythropoietin production, have been shown to cause erythrocytosis:
- Chuvash polycythemia is an autosomal recessive form of erythrocytosis which is endemic in patients from Chuvashia, an autonomous republic within the Russian Federation. Chuvash polycythemia is associated with homozygosity for a C598T mutation in the von Hippel-Lindau gene ("VHL"), which is needed for the destruction of hypoxia-inducible factors in the presence of oxygen. Clusters of patients with Chuvash polycythemia have been found in other populations, such as on the Italian island of Ischia, located in the Bay of Naples.
- PHD2 erythrocytosis: Heterozygosity for loss-of-function mutations of the "PHD2" gene are associated with autosomal dominant erythrocytosis and increased hypoxia-inducible factors activity.
- HIF2α erythrocytosis: Gain-of-function mutations in" HIF2α "are associated with autosomal dominant erythrocytosis and pulmonary hypertension.
Hypoprothrombinemia is found to present itself as either inherited or acquired, and is a decrease in the synthesis of prothrombin. In the process of inheritance, it marks itself as an autosomal recessive disorder, meaning that both parents must be carriers of the defective gene in order for the disorder to be present in a child. Prothrombin is a glycoprotein that occurs in blood plasma and functions as a precursor to the enzyme, thrombin, which acts to convert fibrinogen into fibrin, therefore, fortifying clots. This clotting process is known as coagulation.
The mechanism specific to prothrombin (factor II) includes the proteolytically cleaving, breakdown of proteins into smaller polypeptides or amino acids, of this coagulation factor in order to form thrombin at the beginning of the cascade, leading to stemming of blood loss. A mutation in factor II would essentially lead to hypoprothrombinemia. The mutation is presented on chromosome 11.
Areas where the disease has been shown to present itself at include the liver, since the glycoprotein is stored in this area.
Acquired cases are results from an isolated factor II deficiency. Specific cases include:
1. Vitamin-K Deficiency: In the liver, vitamin K plays an important role in the synthesis of coagulation factor II. Body's capacity in the storage of vitamin K is typically very low. Vitamin K-dependent coagulation factors have a very short half-life, sometimes leading to a deficiency when a depletion of vitamin K occurs. The liver synthesizes inactive precursor proteins in the absence of vitamin K (liver disease). Vitamin K deficiency leads to impaired clotting of the blood and in some cases, causes internal bleeding without an associated injury.
2. Disseminated Intravascular Coagulation (DIC): Involving abnormal, excessive generation of thrombin and fibrin within the blood. Relative to hypoprothrombinemia, due to increased platelet aggregation and coagulation factor consumption involved in the process.
3. Anticoagulants: Warfarin Overdose: Used as a treatment for prevention of blood clots, however, like most drugs, side effects have been shown to increase risk of excessive bleeding by functioning in the disruption of hepatic synthesis of coagulation factors II, VII, IX, and X. Vitamin K is an antagonist to warfarin drug, reversing its activity, causing it to be less effective in the process of blood clotting. Warfarin intake has been shown to interfere with Vitamin-K metabolism.
Because the black cherry tree is the preferred host tree for the eastern tent caterpillar, one approach to prevention is to simply remove the trees from the vicinity of horse farms, which was one of the very first recommendations made concerning MRLS. Next, because the brief time for which the full-grown ETCs are on the ground in the vicinity of pregnant mares, simply keeping pregnant mares out of contact with them is also an effective preventative mechanism. In this regard, one Kentucky horse farm took the approach of simply muzzling mares during an ETC exposure period, an approach which was reportedly effective.
No effective treatment for MRLS is apparent. Mares which aborted are treated with broad-spectrum antibiotics to avoid bacterial infections. The foals born from mares infected with MRLS are given supportive care and supplied with medication to reduce inflammatory response and improve blood flow, but none of the treatments appears to be effective, as the majority of the foals do not survive. Unilateral uveitis is treated symptomatically with antibiotics and anti-inflammatory drugs.