EXAM #1: PATHOLOGY OF ANEMIA Flashcards
What is anemia?
Decreased RBC mass leading to decrease tissue oxygenation
Practically, what is anemia?
- Low Hb
- Low Hematocrit
What is important to remember when you come to the diagnosis of “anemia?”
This is an intermediate diagnosis and you need to find the UNDERLYING CAUSE
How do you classify anemia?
MCV
- Microcytic
- Normocytic
- Macrocytic
Etiology
- Increased blood loss
- Impaired production
- Increased destruction
What are the acute causes of blood loss?
Trauma
What are the chronic causes of blood loss?
- Lesion of GI tract i.e. ulcer, colonic tumor…etc.
- Gynecological disturbance e.g. uterine leiomyoma
What is the cause of Fanconi anemia?
Defect in RBC stem cells
What is the cause of Thalassemia?
Defect in erythroblast maturation
What does Vitamin B12/Folate deficiency result in?
Defective DNA synthesis
What does iron deficiency result in?
Defective Hb synthesis
How does renal failure result in anemia?
Decrease EPO production
EPO is produced in the kidneys
Describe the basic etiology of ACD.
Inflammation induced iron sequestration
What are the primary hepatpoietic neoplasms?
Acute leukemia
Myelodysplasia
Myeloproliferative disorder
What virus is associated with anemia?
Parvovirus B12 infection
This results in an infection of RBC progenitors
What are the inherited RBC membrane disorders?
Hereditary spherocytosis
Hereditary elliptocytosis
What are the inherited enzymes deficiencies that result in anemia?
- HMP shunt (G6PD)
- Glyoclytic (pyruvate kinase)
What are the inherited Hb abnormalities that result in anemia?
- Thalassemia= defective globin synthesis
- Hemoglobinopathies
What are the acquired causes of increased RBC destruction?
- PIGA deficiency
- Autoimmune causes
- Mechanical trauma
What are the autoimmune disorders that can lead to anemia?
1) Transfusion reaction
2) Hemoluytic disease of the newborn
3) Drugs
4) Auto-immune disorders
What are the causes of mechanical trauma to RBCs?
1) DIC
2) Cardiac trauma (valve disorders)
3) Infection– malaria, babesiosis
4) Chemical injury– lead poisoning
5) Sequestration of monoculear phagocyte system–hypersplenism
What is the normal size of a RBC on microscopy?
6-8 um
List the characteristics of a normal PBS (Peripheral Blood Smear).
1) Normochromic= normal Hb
2) Minimal poikilocytosis= irregular shape
3) Minimal anisocytosis= different sizes
4) Nothing “weird”
“Weird” things include nucleated RBCs, infectious organisms, iron aggregates, Howell-Jolly bodies.
Where do you read the PBS?
Near to the tail, but not at the tail
How can you tell a RBC is normochromic?
Central portion is 1/3 of the total diameter
What are the features of a hypochromic RBC? Hyperchromic?
Hypo= central protion is greater than 1/3 of the RBC
Hyper= central portion is less than 1/3 of the RBC
See ppt examples to distinguish anisocytosis and poikilocytosis.
N/A
See ppt. examples to distinguish between hyperchromic and hypochromic.
N/A
What is “polychromasia?”
RBCs with more than one color
- Pink
- Blue
- Blue-gray
This is a sign of anemia?
What are immature RBCs blue or blue-gray?
- H & E staining of retics with RNA
- Straining of the RNA with acid is BLUE
See ppt. example of polychromasia.
N/A
What is normoblastemia? What is this an indication of?
- Presence of nucleated RBCs in PBS
- Hemolytic anemia
See ppt example of normoblastemia.
N/A
What are the characteristics of a spherocyte?
- Spherical
- Small
- Darker in color
What are the the underlying causes of spherocytes on PBS?
- Hereditary spherocytosis
- Autoimmune hemolytic anemia
See ppt. example of spherocytes.
N/A
What is a schistocyte?
“Broken” or fragmented RBC
What are the causes of schistocytes?
- Microangiopathic hemolytic anemia (DIC, TTP, HUS)
- Other hemolytic anemia
Any situation of hemolytic anemia may cause schistocytes.
See ppt. example of a schistocyte.
N/A
What is punctate basophilia/ basophilic stippling?
Tiny blue dots in the periphery of the RBC
What are the causes of punctate basophilia?
- Lead poisoning
- Severe anemia
- Severe infection
- Drugs
- Alcoholism
See ppt slide example of basophilic stippling.
N/A
What is a Howell-Jolly body or H-J body?
- RBC with a purple dot
- Purple nuclear remnant that are LARGER than basophilic stippling
What causes Howell-Jolly bodies?
- S/p splentectomy
- Hemolysis
Spleen cannot rid the body of abnormal RBCs.
See ppt example of H-J body.
N/A
What are the features of reticulocytes?
Blue staining cell with blue staining darker central features
See ppt. examples of reticulocytes.
N/A
List the causes of microcytic anemia.
1) Iron deficiency
2) ACD
3) Thalassemia
4) Siderblastic anemia
What are the causes of defects in heme synthesis?
1) Iron deficiency anemia
2) ACD
3) Sideroblastic anemia
What causes defects in the synthesis of globin chains (alpha or beta)?
Thalassemia
See ppt example of microcytic anemia.
N/A
What is a typical reference for RBC size in a PBS?
Lymphocyte–the RBC should be the same size as the NUCLEUS of the lymphocyte
What are the common causes of macrocytic anemia?
1) Vitamin B12/ Folate deficiency–>decreased DNA synthesis
2) Alcohol use–>increased RBC membrane
3) Liver disease
4) Reticulocytosis
5) Myelodysplastic syndrome*
6) Hypothyroidism*
*uncommon causes
What is the common cause of normocytic anemia?
Blood loss
Describe the physiologic response to acute blood loss.
1) Intravascular shift of water
2) Hemodilution
3) EPO stimulation
Reticulocytes appear in peripheral blood after 5 days.
