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Little vitamin b12 the intrinsic factor secreted by

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(little Vitamin B12) The intrinsic factor secreted by gastric mucosa, which is required for intestinal absorption of B12 Large, immature RBC, short lifespan, less Hmg Etiology Dietary insufficiency is very rarely a cause Genetic factor has been implicated: more common in light skin women of North American ancestry Often accompanies chronic gastritis (inflammation of GI tract) May also be an outcome of gastric surgery Vitamin B12 deficiency B12 is needed for healthy neurons Lack of it can cause peripheral nerve problem May be reversible Signs and symptoms Tongue is typically enlarged, red, sore, and shiny Decrease in gastric acid leads to nausea and diarrhea Tingling, burning sensation (paresthesia) Aplastic Anemia : results from impairment or failure of bone marrow Etiology: may be temporary or permanent, often idiopathic but possible causes include: Myelotoxins: Such as radiation, industrial chemicals, and drugs Viruses: Particularly hepatitis C Genetic Abnormalities: Such as Myelodysplastic syndrome, or Fanconi’s anemia Diagnostic Test: Blood counts may indicate pancytopenia. A bone marrow biopsy may be required to confirm the cause of the pancytopenia. The erythrocytes are often normal in appearance Signs & Symptoms: Anemia, Leukopenia, and thrombocytopenia Treatment: Removal of any bone marrow suppressants- failure to identify cause and treat effectively is LIFE- THREATENING Hemolytic Anemia: results from excessive destruction of RBCs Causes: Genetic defects
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Immune Reactions Changes in blood chemistry Infections such as malaria Toxins in the blood Antigen-antibody reactions such as incompatible blood transfusions or erthroblastosis fetalis Sickle Cell Anemia (example of hemolytic anemia) Genetic Condition: Autosomal and incomplete dominance Occurs in homozygous recessive More common in African ancestry- 10% of AA are heterozygous for trait Abnormal Hemoglobin (Hbs) Sickle cell crisis occurs when oxygen levels are lowered Hemoglobin is unstable and changes shape in hypoxemia Sickle-shaped cells cluster and stop microcirculation Obstruction leads to infarction and areas of necrosis Multiple infarctions affect brain, bones, organs Clinical signs Anemia, hyperbilirubinemia, jaundice, hemolysis Doesn’t usually appear until child is 12 months old Severe pain due to ischemia of tissues and infarctions Pallor, weakness, tachycardia, dyspnea Splenomegaly Vascular occlusions and infarctions Lungs, and blood vessels are smaller smaller blood vessels of the hands or feet cause hand-foot syndrome Delay of growth and development Congestive heart failure Diagnostic Tests: Carriers of the defective gene can be detected by a simple blood test (hemoglobin electrophoresis), prenatal DNA analysis can also be used Treatment: Hydroxyurea has reduced frequency of crisis, dietary supplements with
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