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Orphanet Journal of Rare Diseases May 2010Alpha-thalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost... (Review)
Review
Alpha-thalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost asymptomatic to a lethal haemolytic anaemia.It is probably the most common monogenic gene disorder in the world and is especially frequent in Mediterranean countries, South-East Asia, Africa, the Middle East and in the Indian subcontinent. During the last few decades the incidence of alpha thalassaemia in North-European countries and Northern America has increased because of demographic changes. Compound heterozygotes and some homozygotes have a moderate to severe form of alpha thalassaemia called HbH disease. Hb Bart's hydrops foetalis is a lethal form in which no alpha-globin is synthesized. Alpha thalassaemia most frequently results from deletion of one or both alpha genes from the chromosome and can be classified according to its genotype/phenotype correlation. The normal complement of four functional alpha-globin genes may be decreased by 1, 2, 3 or all 4 copies of the genes, explaining the clinical variation and increasing severity of the disease. All affected individuals have a variable degree of anaemia (low Hb), reduced mean corpuscular haemoglobin (MCH/pg), reduced mean corpuscular volume (MCV/fl) and a normal/slightly reduced level of HbA2. Molecular analysis is usually required to confirm the haematological observations (especially in silent alpha-thalassaemia and alpha-thalassaemia trait). The predominant features in HbH disease are anaemia with variable amounts of HbH (0.8-40%). The type of mutation influences the clinical severity of HbH disease. The distinguishing features of the haemoglobin Bart's hydrops foetalis syndrome are the presence of Hb Bart's and the total absence of HbF. The mode of transmission of alpha thalassaemia is autosomal recessive. Genetic counselling is offered to couples at risk for HbH disease or haemoglobin Bart's Hydrops Foetalis Syndrome. Carriers of alpha+- or alpha0-thalassaemia alleles generally do not need treatment. HbH patients may require intermittent transfusion therapy especially during intercurrent illness. Most pregnancies in which the foetus is known to have the haemoglobin Bart's hydrops foetalis syndrome are terminated due to the increased risk of both maternal and foetal morbidity.
Topics: Gene Deletion; Hemoglobins, Abnormal; Humans; Mutation; alpha-Globins; alpha-Thalassemia
PubMed: 20507641
DOI: 10.1186/1750-1172-5-13 -
American Family Physician Mar 2007The prevalence of iron deficiency anemia is 2 percent in adult men, 9 to 12 percent in non-Hispanic white women, and nearly 20 percent in black and Mexican-American... (Review)
Review
The prevalence of iron deficiency anemia is 2 percent in adult men, 9 to 12 percent in non-Hispanic white women, and nearly 20 percent in black and Mexican-American women. Nine percent of patients older than 65 years with iron deficiency anemia have a gastrointestinal cancer when evaluated. The U.S. Preventive Services Task Force currently recommends screening for iron deficiency anemia in pregnant women but not in other groups. Routine iron supplementation is recommended for high-risk infants six to 12 months of age. Iron deficiency anemia is classically described as a microcytic anemia. The differential diagnosis includes thalassemia, sideroblastic anemias, some types of anemia of chronic disease, and lead poisoning. Serum ferritin is the preferred initial diagnostic test. Total iron-binding capacity, transferrin saturation, serum iron, and serum transferrin receptor levels may be helpful if the ferritin level is between 46 and 99 ng per mL (46 and 99 mcg per L); bone marrow biopsy may be necessary in these patients for a definitive diagnosis. In children, adolescents, and women of reproductive age, a trial of iron is a reasonable approach if the review of symptoms, history, and physical examination are negative; however, the hemoglobin should be checked at one month. If there is not a 1 to 2 g per dL (10 to 20 g per L) increase in the hemoglobin level in that time, possibilities include malabsorption of oral iron, continued bleeding, or unknown lesion. For other patients, an endoscopic evaluation is recommended beginning with colonoscopy if the patient is older than 50.
Topics: Administration, Oral; Algorithms; Anemia, Iron-Deficiency; Diagnosis, Differential; Female; Ferric Compounds; Ferritins; Humans; Infusions, Parenteral; Iron; Male; Risk Factors; Transferrin
PubMed: 17375513
DOI: No ID Found -
American Family Physician Mar 2022Thalassemia is a group of autosomal recessive hemoglobinopathies affecting the production of normal alpha- or beta-globin chains that comprise hemoglobin. Ineffective...
Thalassemia is a group of autosomal recessive hemoglobinopathies affecting the production of normal alpha- or beta-globin chains that comprise hemoglobin. Ineffective production of alpha- or beta-globin chains may result in ineffective erythropoiesis, premature red blood cell destruction, and anemia. Chronic, severe anemia in patients with thalassemia may result in bone marrow expansion and extramedullary hematopoiesis. Thalassemia should be suspected in patients with microcytic anemia and normal or elevated ferritin levels. Hemoglobin electrophoresis may reveal common characteristics of different thalassemia subtypes, but genetic testing is required to confirm the diagnosis. Thalassemia is generally asymptomatic in trait and carrier states. Alpha-thalassemia major results in hydrops fetalis and is often fatal at birth. Beta-thalassemia major requires lifelong transfusions starting in early childhood (often before two years of age). Alpha- and beta-thalassemia intermedia have variable presentations based on gene mutation or deletion, with mild forms requiring only monitoring but more severe forms leading to symptomatic anemia and requiring transfusion. Treatment of thalassemia includes transfusions, iron chelation therapy to correct iron overload (from hemolytic anemia, intestinal iron absorption, and repeated transfusions), hydroxyurea, hematopoietic stem cell transplantation, and luspatercept. Thalassemia complications arise from bone marrow expansion, extramedullary hematopoiesis, and iron deposition in peripheral tissues. These complications include morbidities affecting the skeletal system, endocrine organs, heart, and liver. Life expectancy of those with thalassemia has improved dramatically over the past 50 years with increased availability of blood transfusions and iron chelation therapy, and improved iron overload monitoring. Genetic counseling and screening in high-risk populations can assist in reducing the prevalence of thalassemia.
Topics: Child, Preschool; Hematologic Diseases; Humans; Infant, Newborn; Iron; Iron Overload; Thalassemia; beta-Globins; beta-Thalassemia
PubMed: 35289581
DOI: No ID Found -
Hematology. American Society of... Dec 2020Inherited microcytic anemias can be broadly classified into 3 subgroups: (1) defects in globin chains (hemoglobinopathies or thalassemias), (2) defects in heme... (Review)
Review
Inherited microcytic anemias can be broadly classified into 3 subgroups: (1) defects in globin chains (hemoglobinopathies or thalassemias), (2) defects in heme synthesis, and (3) defects in iron availability or iron acquisition by the erythroid precursors. These conditions are characterized by a decreased availability of hemoglobin (Hb) components (globins, iron, and heme) that in turn causes a reduced Hb content in red cell precursors with subsequent delayed erythroid differentiation. Iron metabolism alterations remain central to the diagnosis of microcytic anemia, and, in general, the iron status has to be evaluated in cases of microcytosis. Besides the very common microcytic anemia due to acquired iron deficiency, a range of hereditary abnormalities that result in actual or functional iron deficiency are now being recognized. Atransferrinemia, DMT1 deficiency, ferroportin disease, and iron-refractory iron deficiency anemia are hereditary disorders due to iron metabolism abnormalities, some of which are associated with iron overload. Because causes of microcytosis other than iron deficiency should be considered, it is important to evaluate several other red blood cell and iron parameters in patients with a reduced mean corpuscular volume (MCV), including mean corpuscular hemoglobin, red blood cell distribution width, reticulocyte hemoglobin content, serum iron and serum ferritin levels, total iron-binding capacity, transferrin saturation, hemoglobin electrophoresis, and sometimes reticulocyte count. From the epidemiological perspective, hemoglobinopathies/thalassemias are the most common forms of hereditary microcytic anemia, ranging from inconsequential changes in MCV to severe anemia syndromes.
Topics: Anemia; Humans; Iron; Metal Metabolism, Inborn Errors
PubMed: 33275715
DOI: 10.1182/hematology.2020000158 -
Discovery Medicine Sep 2017Pernicious anemia (PA) is an autoimmune disease of multifactorial etiologies characterized by autoimmune chronic atrophic gastritis, cobalamin deficiency (CD) due to... (Review)
Review
Pernicious anemia (PA) is an autoimmune disease of multifactorial etiologies characterized by autoimmune chronic atrophic gastritis, cobalamin deficiency (CD) due to defective absorption of dietary cobalamin from the terminal ileum, and by the presence of intrinsic factor and parietal cell antibodies. PA is a very common cause of CD-related anemia worldwide. Despite advances in the understanding molecular biology and pathophysiology of PA, the diagnosis of PA remains challenging in many circumstances for many clinicians because of its diverse clinical manifestations and the limitations of currently available diagnostic tools. Diagnostic dilemmas could occur when patients with PA present with spuriously normal or high cobalamin levels, normocytic or microcytic anemia, non-anemic macrocytosis, autoimmune hemolytic anemia, pseudo-thrombotic microangiopathy, hyperhomocysteinemia-associated thromboembolism, pseudoleu-kemia, bone marrow failure, bone marrow ring sideroblasts, and neurologic manifestations without anemia or macrocytosis. Herein, we provide an overview of the challenging clinical presentations of PA, diagnostic approach, and management.
Topics: Anemia, Pernicious; Animals; Autoantibodies; Autoimmune Diseases; Gastritis, Atrophic; Humans; Vitamin B 12 Deficiency
PubMed: 28972879
DOI: No ID Found -
Scientific Reports Feb 2023Oral iron is the mainstay of treating iron deficiency anemia. Recent studies indicate better fractional iron absorption with alternate day supplementation. However, the...
Oral iron is the mainstay of treating iron deficiency anemia. Recent studies indicate better fractional iron absorption with alternate day supplementation. However, the optimal supplementation strategy is unclear. We compared effectiveness of daily versus alternate day supplementation of oral iron for treatment of iron deficiency anemia. This double blind, active control, randomized controlled trial was conducted on two hundred adults having hemoglobin 10 g/dL or less with microcytic hypochromic anemia and/or serum ferritin below 50 ng/mL. They were randomized to receive either two Ferrous sulfate tablets containing 60 mg elemental iron (120 mg total) on alternate days or single tablet of 60 mg elemental iron daily for 8 weeks. Primary outcome was mean change in hemoglobin at week 8 from baseline. Mean hemoglobin was 6.53 (± 1.89) and 6.68 (± 1.89) g/dL in the alternate day and daily arms respectively. Mean change in hemoglobin was + 1.05 ± 1.34 g/dL in alternate day arm and + 1.36 ± 1.51 g/dL in daily arm (p = 0.47) at week 8. There were no statistically significant differences between the arms with respect to any secondary outcome. There is no significant difference between alternate day and daily iron administration in improving hemoglobin. Randomized controlled trials enrolling more participants for longer periods of supplementation and evaluating clinically relevant outcomes like change in hemoglobin may be useful in identifying the ideal dosing strategy.Trial Registration: Clinical Trial Registry of India (CTRI/2019/01/017169).
Topics: Adult; Humans; Iron; Anemia, Iron-Deficiency; Hemoglobins; Iron Radioisotopes; Hemoglobins, Abnormal; Administration, Oral; Randomized Controlled Trials as Topic
PubMed: 36725875
DOI: 10.1038/s41598-023-29034-9