Red Blood Cells Flashcards
Which type of hemaglobin is most common in adults?
HgbA is at 97% (two alpha chains and two beta chains)
Which hemaglobins are increased in beta-thalassemia?
HgbA2 (otherwise only 1.5-3%)
and
HgbF (50-90% at birth, <1% in adults)
Normal adult hemoglobin levels for men and women?
Men: 13
Women: >11.5
Hematocrit
Volume of RBCs
Which organs are susceptible to hypoxia?
- Kidney tubules
- myocardium
- brain
- hepatic cells
Locations of extramedullary hematopoiesis?
- Liver
- Lymph nodes
- Spleen
*these sites create RBCs in fetus up until 8 weeks gestation
Pancytopenia
Destruction of all stem cells of WBC, RBC, and platelets
Anisocytosis
Variation in the size of RBC (ex. microcytic, normocytic, macrocytic)
Poikilocytosis
Variation in the shape of RBCs (ex. burr cells, spur cells, sickle cells)
Which two anemias are associated with microcytic cells?
- Iron deficiency
2. Thalassemia
Which two anemias are associated with macrocytic cells?
- Vitamin B12 deficiency (cyanobalmin)
2. Folate deficiency
Pathologic classification of anemias are based on what 3 things?
- Peripheral blood smears
- Measurement of Hg content
- Chemical analysis of hemoglobin
What are the 3 causes of normocytic anemias (diminished marrow capacity)?
- Acute blood loss
- Myelophthitic
- Aplastic
What characterizes the blood smear for acute blood loss?
normochromic, normocytic with increased reticulocytes in recovery phase
Myelophthitic anemia: etiology
space-occupying lesion that destroys bone marrow productive capacity of all formed elements (pancytopenia)
MC cancer causes of myelopthtic anemia
- Breast
- Lung
- Prostate
- Thyroid
Myelopthitic blood smear
- moderate to severe normocytic anemia
- anisopoikilocytosis
- tear drop cells
What is the most common cause of aplastic anemia
idiopathic (2/3)
Name 4 secondary causes of aplastic anemia
- Cytotoxic drugs (NSAIDS, alkylating chemo, insecticides, arsenicals, anticonvulsants)
- Viral infection (CMV, EBV, HIV, Parvo B19, Hep C)
- Radiation therapy
- Benzene
As marrow regenerates, what changes would you expect to see in the blood?
reticulocytes reaching 10-15% after 7 days
What would you expect to see on bone marrow biopsy for aplastic anemia?
- fibroblasts
- fat cells
- scattered lymphocytes
-NO hematopoietic stem cells
What is the most common form of anemia?
iron-deficiency anemia
What do the RBCs look like in iron-deficiency anemia?
hypochromic, microcytic
MC clinical signs of each gender in iron deficiency anemia
Female - menstrual blood loss
Male - GI (colon cancer, bleeding hemorrhoids)
Iron-deficiency anemia: histology
bone marrow is hyperplastic with small normoblasts with absent Fe staining (Prussian blue stain)
What is the treatment for iron deficiency anemia
Ferrous sulfate + vitamin C
What do RBCs look like in thalassemia?
hypochromic, microcytic with target cells
What is the etiology of Thalassemia?
No abnormal hemoglobin is produced. Problem stems from not enough hemoglobin being made
Thalassemia: Clinical manifestations
- Hemolytic anemia: elevated serum FE and indirect bilirubin
- Jaundice
- Splenomegaly