anemia

• Anemia is a lack of red blood cells and/or hemoglobin, resulting in hypoxia
• Three large groups of anemia:

  • Posthemorrhagic anemia (acute or chronic)
  • Anemia caused by disturbances of hematopoiesis
  • Hemolytic anemia caused by enhanced RBCs breakdown
• RBC indices, mainly the mean corpuscular volume (MCV), can narrow the differential diagnosis of deficient erythropoiesis and help determine further testing
• Acute post hemorrhagic anemia signs and symptoms:

  • Feeling weak, tired, dizzy
  • Fast or irregular heartbeat
  • Pale or cold clammy skin
  • Shortness of breath or fast shallow breaths
  • Nausea
  • Urinating little or not at all
  • Trouble concentrating or confusion
• Post hemorrhagic anemia clinical/pathophysiologic stages:

  • Spasm stage with narrowed blood vessel lumen and erythrocytes pumped to periphery
  • Hydraulic phase with tissue fluid plumped into bloodstream, often normochromic anemia
  • Bone marrow phase with active proliferation-differentiation of erythropoietin cell
• Chronic post hemorrhagic anemia:

  • RBC number and HB content decreased
  • Hypochromic and hyporegenerative anemia
  • Degenerative forms: hypochromic erythrocytes, poikilocytosis, anisocytosis with microcytes
  • WBC: leukopenia, neutropenia, relative lymphocytosis
  • Bone marrow: RBCs saturation with hemoglobin process violated, decrease in erythroblasts maturation
• Iron deficiency anemia:

  • Most common type of anemia due to lack of mineral iron
  • Iron enters body alimentary way, facilitated by vitamin C
  • Absorption of iron in upper part of intestinal tract, carried by transferrin
  • Blood picture: decrease in hemoglobin, hypochromia, microanizocytosis, poikilocytosis, schizocytosis
• Macrocytic anemia:

  • Caused by impaired DNA synthesis leading to megaloblastosis
  • Deficiencies of vitamin B12 or folate
  • Other causes: chronic alcohol intake, liver disease, Myelodysplastic syndromes, some drugs
• Vitamin B12 deficiency anemia:

  • More common in people from northern Europe
  • Caused by lack of intrinsic factor (pernicious anemia), surgery removing/bypassing end of small intestine, chronic gastritis, gastrectomy, autoimmune condition
• Symptoms of vitamin B12 deficiency anemia:

  • Weak muscles
  • Numb or tingling feeling in hands and feet
  • Trouble walking
  • Nausea
  • Decreased appetite
  • Weight loss
  • Irritability
  • Lack of energy or fatigue
  • Diarrhea
  • Smooth and tender tongue
  • Fast heart rate
• Hemolytic anemia:

  • Disorder where RBCs are destroyed faster than made, called hemolysis
  • Types include Sickle Cell Anemia, Thalassemia, Hereditary Spherocytosis, Hereditary Elliptocytosis, Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency, Pyruvate Kinase Deficiency, Immune Hemolytic Anemia, Mechanical Hemolytic Anemia
• Immune Hemolytic Anemia:

  • Red blood cells destroyed earlier than normal due to antibodies forming against own RBCs
  • Immune system mistakenly recognizes blood cells as foreign
• Mechanical Hemolytic Anemia:

  • Form of hemolytic anemia due to mechanically induced damage to RBCs
  • Non-immune mediated destruction of RBCs, associated with blood transfusion
• Sickle cell anemia:

  • Inherited disorder with insufficient healthy red blood cells to carry oxygen
  • Rigid, sticky sickle-shaped cells can block blood flow and oxygen to body parts
• Thalassemia:

  • Inherited blood disorder with abnormal form of hemoglobin
  • Excessive destruction of RBCs leading to anemia
  • Two main forms: alpha thalassemia (mutation in alpha globin) and beta thalassemia (beta globin is affected)
• Thalassemia signs and symptoms:

  • Fatigue
  • Weakness
  • Pale or yellowish skin
  • Facial bone deformities
  • Slow growth
  • Abdominal swelling
  • Dark urine
• Target cells in thalassemia:

  • Thin RBCs with overabundance of cell membrane, assuming bell shape in circulation