BLOOD LECTURE 1: ANEMIA Flashcards
What are the components of blood, and what percent of the blood volume do they make up?
- Plasma: 55%
- RBCs: 45%
- Buffy coat (WBCs, platelets): <1%
What are the 2 categories of leukocytes?
Polymorphonuclear granular cells
Mononuclear cells
What are the 3 types of PMN cells?
Neutrophils
Eosinophils
Basophils
What are the 2 types of mononuclear cells?
Monocytes
Lymphocytes
What is the precursor to all blood cells?
Pluripotent stem cell
Pluripotent stem cells differentiate into which two precursor cells?
- Myeloid stem cell
- Lymphoid stem cell
Myeloid stem cells are the precursor to which 5 types of cells?
- Erythrocyte
- Platelets
- Mast cells
- PMNs
- Monocytes (macrophages)
What is the precursor cell to platelets?
Megakaryocyte
Lymphoid stem cells are the precursor to which 3 types of cells?
- T cells
- B cells
- NK cells
B cells further differentiate into what kind of cells?
Plasma cells
What is the name for the iron containing compound found in erythrocytes?
Heme
What is the globin part of hemoglobin composed of?
Protein
Iron from heme is transported to the liver and then to the bone marrow via which carrier glycoprotein?
Transferrin
Which 2 pigments from heme are disposed of through the liver and GI tract?
Bilirubin and biliverdin
Iron transported to the liver by transferrin become what iron containing blood protein?
Ferritin
What is the term for anemia where the red cell mass is normal but plasma volume is high?
Relative/dilutional anemia
What is the term for anemia where there is a true decrease in erythrocyte numbers, either due to a decrease in production or an increase in breakdown?
Absolute anemia
What are 3 reasons for decreased production/maturation of RBCs?
- Diet
- Genetics
- Bone marrow disease
What are 3 reasons for increased destruction of RBCs?
- Autoimmune
- Infection
- Genetics
Besides decreased production and increased destruction of RBCs, what is a 3rd reason for anemia?
Acute or chronic blood loss
What is the main effect of anemia?
Tissue hypoxia
What are 3 compensatory mechanisms to restore tissue O2?
- Increased heartrate and cardiac output
- Increased EPO
- 2,3-BPG binds to deoxygenated HGB, which makes O2 detach from it easier so it will go into the tissues
What are the symptoms of mild anemia?
Usually asymptomatic, although elderly with comorbid conditions may have symptoms
What are 3 important signs of severe anemia?
- Fainting
- Chest pain/angina
- MI
What does hematocrit indicate?
The ratio of RBCs to plasma in a blood specimen
What does the lab value mean corpuscular volume (MCV) indicate?
The average volume of 1 red blood cell in a specimen
What is the difference between mean cell hemoglobin (MCH) and mean cell hemoglobin concentration (MCHC)?
MCH: Average amount of HGB per each RBC
MCHC: Average amount of HGB per volume of RBCs
What is the name for immature RBCs?
Reticulocytes
Which 2 lab tests detect hemolysis?
Bilirubin, lactate dehydrogenase
Which lab tests can determine RBC morphology and the presence of parasites?
Blood smear
What are 3 classifications of anemia based on cell size?
Normocytic, microcytic, macrocytic
What are 2 classifications of anemia based on cell hemoglobin content?
Normochromic, hypochromic
What are 4 kinds of anemia related to decreased erythrocyte production?
- Iron deficiency
- Megaloblastic
- Chronic disease
- Aplastic
What are 4 kinds of anemia related to increased erythrocyte destruction?
- Immune related hemolytic
- Spherocytosis
- Sickle cell
- Thalassemias
What are 4 possible causes for iron deficiency anemia with examples?
- Iron loss (bleeding)
- Insufficiency dietary intake/absoprtion (celiac)
- Impaired iron storage (ferritin deficient, liver disease)
- Increased iron requirement (pregnancy)
What are 3 unique clinical manifestations of iron deficiency anemia?
- Koilonychia
- Atrophic glossitis
- Pica
What does the lab test iron binding capacity indicate?
Function of transferrin
How does chronic disease cause anemia?
Inflammation suppresses RBC synthesis
Why does CKD in particular cause anemia?
Impaired EPO production
What is the primary cause of megaloblastic anemia?
Vitamin B12 or folic acid deficiency impairs DNA synthesis/RBC maturation
What is the morphological appearance of RBCs in megaloblastic anemia?
Macrocytic, nucleated
What is the consequence of the abnormal RBCs produced in megaloblastic anemia?
They are destroyed prematurely
What are 3 reasons for vitamin B12 deficiency?
- Diet/absorption (vegan, celiac)
- Parasitic infection
- Lack of intrinsic factor
What is the term for anemia caused by lack of intrinsic factor?
Pernicious anemia
What are 4 possible causes for lack of intrinsic factor?
- Autoimmune attack of parietal cells
- Gastric surgery
- Chronic gastritis
- Lifestyle factors
What are 2 possible reasons for folate deficiency?
- Pregnancy
- Medication side effects
What are 2 diagnostic results that would indicate pernicious anemia?
- Autoantibodies against instrinsic factor/parietal cells
- Gastric atrophy
What are 2 ways megaloblastic anemia due to folate deficiency differ from megaloblastic anemia due to vitamin B12 deficiency?
- Develops more rapidly
- Fewer neurological symptoms
Which type of anemia is due to injury/reduction of hematopoietic stem cells in the bone marrow?
Aplastic anemia
What are 5 possible causes for aplastic anemia?
- Idiopathic (most common)
- Myelotoxins
- Viral infection
- Immune disorders
- Genetic (Fanconi’s)
What are the 2 categories of hemolytic anemias based on etiology?
- Intracorpuscular
- Extracorpuscular
What are 3 signs of hemolytic anemia?
- Splenomegaly
- Increased EPO
- Accumulation of Hgb degradation products
What are
What are 3 signs of megaloblastic anemia?
- Abdo pain, GI upset
- Signs of hemolysis i.e. jaundice, splenomegaly
- Neurocognitive changes
What 2 CBC/blood smear results would indicate megaloblastic anemia?
- High MCV
- Macrocytic RBCs
How are iron deficiency anemia, anemia of chronic disease, and megaloblastic anemia treated?
- Supplements (iron, B12, folate)
- Treat underlying condition
- EPO (in CKD)
What 2 CBC/blood smear results would indicate aplastic anemia?
- Pancytopenia
- Normocytic RBCs
What other diagnostic study can be performed to diagnose aplastic anemia?
Bone marrow aspiration/biopsy
What 2 CBC results would indicated hemolytic anemia?
- Low RBCs
- High reticulocytes
Other than CBC findings, what 3 lab findings would indicate hemolytic anemia?
- Elevated bilirubin
- Elevated lactate dehydrogenase
- RBC binding antibodies
What are 3 general treatments for hemolytic anemias?
- Blood transfusion
- Splenectomy
- Immunosuppressants
What is used to prevent hemolytic anemia in pregnant Rh-negative women?
RhoGAM
What type of hemolytic anemia involve a genetic mutation in membrane proteins, causing RBCs to become more fragile?
Spherocytosis
What is the prognosis for spherocytosis?
Cured with splenectomy, but risk for infection
Which type of hemolytic anemia involves a genetic mutation in Hgb beta chains, causing RBC distortion under hypoxic conditions?
Sickle cell anemia
What causes hemolytic crisis in sickle cell anemia?
Sickled cells get stuck in microcirculation
Other than general symptoms of hemolytic anemia, what is 1 major consequence of sickle cell anemia?
Ischemia and infarction of major organs
Which diagnostic test is used to detect abnormal types of hemoglobin such as HbS?
Hemoglobin electrophoresis
Other than general treatments for hemolytic anemias, what are 3 ways sickle cell anemia is treated?
- Lifestyle changes (avoid infection and physical exertion)
- Hydroxyurea: stimulates production of fetal Hgb
- Bone marrow transplant
Which type of hemolytic anemia involves genetic mutation of globin chain formation, impairing RBC structure and maturation?
Thalassemia
Other than general symptoms of hemolytic anemias, what are 2 signs of thalassemia?
- Iron overload
- Skeletal changes
What blood smear findings would indicate thalassemia?
Microcytic, hypochromic RBCs
What are 2 ways to treat thalassemia?
- BMT
- Iron chelation