Anemia

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Revision as of 00:17, 12 February 2007 by imported>Michael Benjamin
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Anemia

Anemia is a condition of the blood characterized by too few red blood cells to support normal physiology. Anemia (AmE) or anaemia (BrE), from the Greek (Ἀναιμία) meaning "without blood", refers to a deficiency of red blood cells (RBCs) and/or hemoglobin. Homeostasis dictates that red cell production and destruction are usually balanced in an organism. Anemias are caused by either excess red cell destruction, or underproduction of red cells. Reduction in the red blood cell content of blood can have a wide range of clinical consequences, from no noticeable symptoms for gradual-onset anemia, to cardiovascular collapse and death from rapid, profound reductions, such as seen in bleeding. Hemoglobin is the pigmented protein in blood that carries oxygen; reductions in blood hemoglobin concentrations in anemia can lead to decreased oxygen delivery to tissues.

Underproduction anemias (hypoproliferative)

Vitamin and mineral deficiency

Iron (Fe) Deficiency - (writing words, will add/edit later) DMT-1, Duodenum, Transferrin, hypochromic, microcytic, high RDW, clathryn coated pit, free iron too toxic for cell (maybe this will go in subarticle), ferritin/hemosiderin (storage form), regulated by IRP (iron response protein) - binds to mRNA of ferritin blocks translation. when bound to TfR mRNA stabilizes increasing uptake of Fe.

Reasons for Fe def : Increase Losses (blood loss - uterus, GI, other), Increase requirements (growth, pregnancy), Decrease Intake (infants and children), and Decreased absorption

Myelodysplastic syndrome

Aplastic anemia

(written in stream of consciousness style - will clean up later but feel free to start editing for me) Drugs, Radiation, Infections, Immune, Idiopathic

Drugs that cause aplastic probably are indirectly causing through immune response. Radiation is a direct cause. Infections like T.B. can cause aplastic anemia. If you had TB and aplastic anemia one would probably treat with immune suppression and addition to TB regimen. If you miss the underlying cause and treat with only immune suppression, you will kill the patient (faster?). (Debating whether to insert a famous example of a famous patient who died of this)

Myeloma and other malignancies

Hereditary anemia syndromes

Substance-induced anemias

Excess red cell destruction anemias

Hemolytic anemias

Bleeding