A 72 year old man presented at the Outpatient Clinic because of anemia

Discussion in 'Plab 1 and 2 forum' started by Neha Gupta, Jul 8, 2013.

  1. Neha Gupta

    Neha Gupta Active Member

    Q. A 72 year old man presented at the Outpatient Clinic because of anemia. His past medical history included peripheral neuropathy detected a few years previously and chronic alcoholism. A bone marrow aspiration revealed erythroid hyperplasia. Prussian blue staining revealed normoblasts with augmentation of mitochondrial iron. A ringed appearance to the nucleus when stained with iron stains (Prussian blue) is typically seconday to :

    a) failure of alpha chain production

    b) failure of beta chain production

    c) a deficiency of B12

    d) a deficiency of iron

    e) a deficiency of folate

    f) an inability to manufacture heme
    Last edited: Jul 11, 2013
  2. Neha Gupta

    Neha Gupta Active Member

    f as an ans

    In sideroblastic anemia the iron granules are large, numerous and are located in a ring around the nucleus. These abnormal aggregates are ferritin precipitates located in the mitochondria. Sideroblastic anemia is very heterogeneous, often confusing group of anemias. Until recently they have escaped classification or have been randomly scattered within other anemia groups. Sideroblastic anemia is characterized by an inability to manufacture heme. This divergent group have several clinical and laboratory features in common: 1. Hypochromia - usually minimal with cell size ranging from microcytic to slightly macrocytic. 2. Dimorphic blood picture - a hypochromic microcytic population coexists with a normocytic normochromic population. 3. Bone marrow - erythroid hyperplasia with dyserythropoiesis and a maturation arrest. Erythroid phagocytosis usually present, leukophagocytosis may also be present. 4. Iron - increased 5. Ringed sideroblasts - present >10% 6. Red cell life span - normal 7. Abnormal hemoglobins - absent Under normal circumstances 40 to 60% of the normoblasts, 1% or less of the retics and less than .1% of mature erythrocytes contain stainable iron by the Prussian Blue Reaction. These granules are small, rarely exceed five or six per cell becoming less numerous as the cell matures and are randomly distributed in the cytoplasm of the cell. Heme synthesis is abnormal while iron absorption and transport remains normal. The excess iron accumulates in the mitochondria waiting to be inserted into the heme ring. Heme production begins with the enzymatic combination of succinate and glycine to form delta ALA. ALA synthetase is the enzyme that controls this step. At least five more enzymaticaly ontrolled modifications occur before iron can be inserted into the protoporphyrin IX ring to form heme. If any of these enzymes are abnormal iron accumulates

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