I Always Feel Tired

I Always Feel Tired

1. Histology of RBC

   • Erythrocytes are the most abundant cells in blood. They have a unique biconcave disk appearance ,are anucleate (without nuclei), and have no organelles after they mature.
   • Erythrocytes are produced in the red bone marrow and are transported into the blood circulation through the walls of sinusoidal capillaries in the marrow. Their life span is about 120 days. Aged erythrocytes are destroyed by macrophages in the spleen, liver, and bone marrow.

2. physiology of RBCs

   • Their function is to transport oxygen to peripheral tissues and carry carbon dioxide out of tissues. Hemoglobin binds with oxygen to form oxyhemoglobin when the O2 level is high (lung) and binds with CO2 to form carbaminohemoglobin when the CO2 level is high (tissue).
   • Production of RBC (erythropoiesis) The mother stem cell within the bone marrow is called pluripotential stem cell which can proliferate and differentiate under certain controlling growth factors to form colonies of cells (CFU)(colony forming units). These CFU can also proliferate and differentiate,under control, to form adequate amounts of mature cells (RBC, WBC, & plt.).

3. pathology of RBCs

   • Anemias
     • Anemia means low Hb level or low number of RBC.
     • types
       • Hypochromic microcytic
         • causes
           • Iron deficiency anemia
             • causes
               • Poor iron diet
               • Blood loss
               • Malabsorption
               • Physiologically increased iron demands
             • Clinical features
               • Picca,Pale skin, pale plamar/plantar creases,pale conjunctivae, & pale sublingual,Koilonychia,palpitation,tiredness..etc
             • investigation
               • CBC
               • Blood film
               • other differential tests
           • Anemia of chronic disorders
           • Thalassemias
             • major
             • minor
             • intermedia
           • Lead poisoning
           • Sideroblastic anemia
           • Porphyria.
       • Normochromic normocytic
       • normochromic Macrocytic
         • causes
           • Megaloblastic anemia
           • Aplastic anemia
           • Reticulocytosis
           • Liver disease
           • Pregnancy.
           • Hypothyroidism.
           • other causes

4. Hematopoesis

   • Erythropoiesis
     • process of formation of RBCs by marrow stem cells from pronormoblast to the mature RBCs
     • Regulated by 1-various nutrients like iron, proteins and vitamin,2- Erythropoietin
   • myelopoiesis
   • megakaryocypoiesis
   • lemphopoiesis