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Autoimmune hemolytic anemia
Glucose-6-phosphate dehydrogenase (G6PD) deficiency
Hemolytic disease of the newborn
Paroxysmal nocturnal hemoglobinuria
Pyruvate kinase deficiency
Sickle cell disease (NORD)
Folate (Vitamin B9) deficiency
Vitamin B12 deficiency
Anemia of chronic disease
Iron deficiency anemia
Vitamin K deficiency
Langerhans cell histiocytosis
Essential thrombocythemia (NORD)
Polycythemia vera (NORD)
Acute intermittent porphyria
Porphyria cutanea tarda
Disseminated intravascular coagulation
Von Willebrand disease
Monoclonal gammopathy of undetermined significance
Thrombotic thrombocytopenic purpura
Antithrombin III deficiency
Factor V Leiden
Protein C deficiency
Protein S deficiency
Coagulation disorders: Pathology review
Extrinsic hemolytic normocytic anemia: Pathology review
Heme synthesis disorders: Pathology review
Intrinsic hemolytic normocytic anemia: Pathology review
Leukemias: Pathology review
Lymphomas: Pathology review
Macrocytic anemia: Pathology review
Microcytic anemia: Pathology review
Mixed platelet and coagulation disorders: Pathology review
Myeloproliferative disorders: Pathology review
Non-hemolytic normocytic anemia: Pathology review
Plasma cell disorders: Pathology review
Platelet disorders: Pathology review
Thrombosis syndromes (hypercoagulability): Pathology review
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Megaloblastic Anemia: Folate Deficiency & Vitamin B12 Deficiency
folate deficiency p. 426
folate deficiency and p. 426
folate deficiency caused by p. 426
folate deficiency with p. 426
Folate deficiency is a clinical condition that occurs because of low level of folate or folic acid in the body. This can lead to a variety of problems ranging from anemia in individuals from all age groups to neural tube malformation in fetuses.
Folate, also known as vitamin B9, mainly comes from eating leafy greens and citrus fruits like oranges and lemons and, nowadays, many countries fortify foods like grains and cereals with folate.
Now, folic acid present in these food items is generally in polyglutamate form, which are basically chains of an amino acid called glutamic acid.
Because of the carboxyl group present in its structure, the chain is negatively charged making it polar and soluble in water, which is a polar molecule but not soluble in lipids which are nonpolar molecules.
So the polyglutamate residues of folic acid are almost non-absorbable from the GI tract, where all the cells are surfaced with lipid cell membranes.
So, to make them absorbable, when polyglutamate residues reach a portion of the small intestine called the jejunum, special enzymes present at the jejunal mucosa cut down the polyglutamate residues into monoglutamate.
Monoglutamate is smaller, and is less negatively charged, so these monoglutamate residues of folic acids can pass through the cell membrane and enter the jejunal cells, where they are converted into tetrahydrofolic acid or in short THF by the enzyme tetrahydrofolate reductase.
These THFs then get methylated into a more stable form called methyl-THF. Once formed, the methyl-THF then leaves the jejunal cell and enters the bloodstream.
Some of it goes to the liver and get stored for a short period of 2-3 months, while most of it is used up for metabolic activity inside various cells around the body.
Folate (vitamin B9) is a water-soluble vitamin that is mainly found in leafy green vegetables and fruits. It is important for the development of new cells, and it helps to form red blood cells. A folate deficiency can lead to anemia, and it can also increase the risk of neural tube defects in newborn babies. Symptoms of a folate deficiency can include fatigue, shortness of breath, and a pale complexion.
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