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Obstetrics and Gynecology Oct 2021Anemia is defined as a low red blood cell count, a low hematocrit, or a low hemoglobin concentration. In pregnancy, a hemoglobin concentration of less than 11.0 g/dL in...
Anemia is defined as a low red blood cell count, a low hematocrit, or a low hemoglobin concentration. In pregnancy, a hemoglobin concentration of less than 11.0 g/dL in the first trimester and less than 10.5 or 11.0 g/dL in the second or third trimester (depending on the guideline used) is considered anemia. Anemia is the most common hematologic abnormality in pregnancy. Maternal anemia is associated with adverse fetal, neonatal and childhood outcomes, but causality is not established. Maternal anemia increases the likelihood of transfusion at delivery. Besides hemodilution, iron deficiency is the most common cause of anemia in pregnancy. The American College of Obstetricians and Gynecologists recommends screening for anemia with a complete blood count in the first trimester and again at 24 0/7 to 28 6/7 weeks of gestation. Mild anemia, with a hemoglobin of 10.0 g/dL or higher and a mildly low or normal mean corpuscular volume (MCV) is likely iron deficiency anemia. A trial of oral iron can be both diagnostic and therapeutic. Mild anemia with a very low MCV, macrocytic anemia, moderate anemia (hemoglobin 7.0-9.9 g/dL) or severe anemia (hemoglobin 4.0-6.9 g/dL) requires further investigation. Once a diagnosis of iron deficiency anemia is confirmed, first-line treatment is oral iron. New evidence suggests that intermittent dosing is as effective as daily or twice-daily dosing with fewer side effects. For patients with iron deficiency anemia who cannot tolerate, cannot absorb, or do not respond to oral iron, intravenous iron is preferred. With contemporary formulations, allergic reactions are rare.
Topics: Administration, Oral; Adult; Anemia, Iron-Deficiency; Blood Transfusion; Child; Drug Administration Schedule; Erythropoietin; Female; Hemoglobins; Humans; Infant, Newborn; Iron; Practice Guidelines as Topic; Pregnancy; Pregnancy Complications, Hematologic; Pregnancy Outcome; Pregnancy Trimesters
PubMed: 34623079
DOI: 10.1097/AOG.0000000000004559 -
Journal of General and Family Medicine Oct 2017Anemia is one of the most common health problems in the primary care setting. Macrocytosis in adults is defined as a red blood cell (RBC) mean corpuscular volume (MCV)... (Review)
Review
Anemia is one of the most common health problems in the primary care setting. Macrocytosis in adults is defined as a red blood cell (RBC) mean corpuscular volume (MCV) >100 femtoliter (fL). Macrocytic anemias are generally classified into megaloblastic or nonmegaloblastic anemia. Megaloblastic anemia is caused by deficiency or impaired utilization of vitamin B12 and/or folate, whereas nonmegaloblastic macrocytic anemia is caused by various diseases such as myelodysplastic syndrome (MDS), liver dysfunction, alcoholism, hypothyroidism, certain drugs, and by less commonly inherited disorders of DNA synthesis. Macrocytic anemias are treated with cause-specific therapies, and it is crucial to differentiate nonmegaloblastic from megaloblastic anemia. Because MDS and myeloid neoplasms commonly affect the elderly, primary care physicians may encounter more cases of macrocytic anemias in the near future, as the older population increases. When MDS is suspected along with leukocytopenia and/or thrombocytopenia with anemia, a hematology consultation may be appropriate.
PubMed: 29264027
DOI: 10.1002/jgf2.31 -
Revista Clinica Espanola Feb 2023Vitamin B12, or cobalamin, belongs to the group of water-soluble vitamins and is ingested through food of animal origin such as eggs, milk, red meat and poultry, fish,... (Review)
Review
Vitamin B12, or cobalamin, belongs to the group of water-soluble vitamins and is ingested through food of animal origin such as eggs, milk, red meat and poultry, fish, and shellfish. Its clinical indication is the treatment of hypovitaminosis B12 administered orally or intramuscularly in the form of hydroxocobalamin. Hypovitaminosis B12 is mainly caused by deficient dietary intake (individuals with malnutrition, vegetarians or vegans, older adults, pregnant people, individuals with alcohol use disorder); when intestinal absorption is reduced (atrophic gastritis, malabsorption syndrome, gastrointestinal surgery); and for causes associated with the intake of drugs (antacids, metformin). Hypervitaminosis B12 has been associated with renal failure; liver diseases such as cirrhosis and acute-phase hepatitis; alcohol use disorder with or without liver involvement; solid tumors of the lung, liver, esophagus, pancreas, and colorectum; and in hematological malignancies such as leukemia and bone marrow dysplasia.
Topics: Female; Animals; Pregnancy; Vitamin B 12; Alcoholism; Vitamin B 12 Deficiency; Anemia, Megaloblastic; Vitamins
PubMed: 36669740
DOI: 10.1016/j.rceng.2022.11.004 -
FP Essentials Jul 2023Macrocytic anemia is divided into megaloblastic and nonmegaloblastic causes, with the former being more common. Megaloblastic anemia results from impaired DNA synthesis,...
Macrocytic anemia is divided into megaloblastic and nonmegaloblastic causes, with the former being more common. Megaloblastic anemia results from impaired DNA synthesis, leading to release of megaloblasts, which are large nucleated red blood cell precursors with chromatin that is not condensed. Vitamin B12 deficiency is the most common cause for megaloblastic anemia, although folate deficiency also can contribute. Nonmegaloblastic anemia entails normal DNA synthesis and typically is caused by chronic liver dysfunction, hypothyroidism, alcohol use disorder, or myelodysplastic disorders. Macrocytosis also can result from release of reticulocytes in the normal physiologic response to acute anemia. Management of macrocytic anemia is specific to the etiology identified through testing and patient evaluation.
Topics: Humans; Anemia, Macrocytic; Anemia; Anemia, Megaloblastic; Alcoholism; DNA
PubMed: 37390397
DOI: No ID Found -
Discovery Medicine 2019Pernicious anemia (PA), the commonest cause of cobalamin deficiency (CD) in the world, is an autoimmune disease of multifactorial origin and is characterized by chronic... (Review)
Review
Pernicious anemia (PA), the commonest cause of cobalamin deficiency (CD) in the world, is an autoimmune disease of multifactorial origin and is characterized by chronic atrophic gastritis (CAG) and defective absorption of cobalamin from the terminal ileum due to interference by the intrinsic factor (IF) antibodies. PA-related CD is a lengthy process, which if untreated, can lead to irreversible hematological and neurological sequelae. Although safe and effective therapy is available and the management of PA is straightforward, the diagnosis of PA can be extremely difficult to obtain due to myriad and diverse clinical presentations, frequently coexisting diseases, and limitations of currently available diagnostic tests. Diagnostic dilemmas may occur when PA patients present with normal or spuriously high serum cobalamin levels, dysplastic features of ring sideroblasts in the bone marrow (BM), hemolysis, and concomitant diseases such as iron deficiency or thalassemia. Herein, the author discusses an overview of diagnostic difficulties, with regards to morphological mimics, coexisting diseases, limitations of currently available tests, and how to diagnose PA in the era of imperfect laboratory tests.
Topics: Anemia, Pernicious; Autoantibodies; Biomarkers; Hematologic Tests; Humans
PubMed: 32053765
DOI: No ID Found -
Blood May 2020
Topics: Adult; Anemia, Pernicious; Female; Humans; Prognosis; Vitamin B 12; Vitamin B 12 Deficiency; Vitamin B Complex
PubMed: 32379881
DOI: 10.1182/blood.2020005344 -
Current Opinion in Hematology May 2024Over the last century, the diseases associated with macrocytic anemia have been changing with more patients currently having hematological diseases including... (Review)
Review
PURPOSE OF REVIEW
Over the last century, the diseases associated with macrocytic anemia have been changing with more patients currently having hematological diseases including malignancies and myelodysplastic syndrome. The intracellular mechanisms underlying the development of anemia with macrocytosis can help in understanding normal erythropoiesis. Adaptations to these diseases involving erythroid progenitor and precursor cells lead to production of fewer but larger red blood cells, and understanding these mechanisms can provide information for possible treatments.
RECENT FINDINGS
Both inherited and acquired bone marrow diseases involving primarily impaired or delayed erythroid cell division or secondary adaptions to basic erythroid cellular deficits that results in prolonged cell division frequently present with macrocytic anemia.
SUMMARY OF FINDINGS
In marrow failure diseases, large accumulations of iron and heme in early stages of erythroid differentiation make cells in those stages especially susceptible to death, but the erythroid cells that can survive the early stages of terminal differentiation yield fewer but larger erythrocytes that are recognized clinically as macrocytic anemia. Other disorders that limit deoxynucleosides required for DNA synthesis affect a broader range of erythropoietic cells, but they also lead to macrocytic anemia. The source of macrocytosis in other diseases remains uncertain.
Topics: Humans; Erythropoiesis; Anemia; Anemia, Macrocytic; Erythrocytes; Myelodysplastic Syndromes
PubMed: 38334746
DOI: 10.1097/MOH.0000000000000804