exam 2 Flashcards
How are anemias classified according to cause?
Increased red cell destruction= hemolytic
How are anemias classified according to morphology?
Macrocytic Normochromic- means they’re not low in iron
Microcytic Hypocromic
Normocytic Normochromic-both normal
(No such thing as “hyperchromic”)
What are the symptoms of anemia?
Weak, , hypotension (low BP), fatigue, syncope
Given the values for the red blood cell indices, suggest a possible diagnosis in the following situations:
Increased MCV Normal MCHC
Macrocytic Anemias; liver disease, B12 deficiency, Folate deficiency, Pernicious anemias, alcoholism
Given the values for the red blood cell indices, suggest a possible diagnosis in the following situations:
MCV and MCHC Normal
hemoglobinopathies
MCV Decreased MCHC Decreased
Microcytic- Iron def anemia, Sideroblastic anemia, thalassemia, lead poisoning
What is the peripheral blood picture in vitamin B12 and folate deficiency?
Pancytosemia - all cells decreased
What do you see in the bone marrow with the peripheral blood picture in Vitamin B12 and folate deficiency?
Giant bands, precursor cells, megaloblasts
What deficiency diseases cause megaloblastic erythropoiesis
Vitamin B12 & Folic Acid
what cellular components are affected in megaloblastic erythropoiesis
Affects DNA & RNA
What specifically causes pernicious anemia?
Lack of intrinsic factor
What main clinical manifestation distinguishes Vitamin B12 deficiency from folic acid deficiency?
Pernicious anemia. Clinical manifestation is neurological symptoms relating to the myelin sheath.
What conditions can produce non-megaloblastic macrocytic anemia?
Alcoholism
liver disease
hypothyroidism.
What poikilocytes are often seen in liver disease?
round macrocytes, target cells,
What parameters are decreased in aplastic anemia and what bone marrow precursor cells are decreased?
All precursor cells decreased, all cells decreased.
What is the peripheral blood picture in aplastic anemia
normocytic normochromic cells- no signs of increased red cell formation
decreased bone marrow
what would the reticulocyte count be expected to be in aplastic anemia?
Retic= decreased
What are the most common causes of aplastic anemia?
Chemical exposure: Benzene and chloramphenicol
Radiation
drugs
Name several causes of myelophthisic anemia?
Leukemia, Lymphomas, Multiple myeloma, MetastaticCarcinoma
What poikilocyte is especially associated with myelophthisic anemia because it indicates extramedullary hematopoiesis?
Tear drop cells
What is the blood picture in chronic renal disease?
Normocytic normochromic-burr cells, helmet cells, schistocytes
What is the main cause of anemia due to renal disease
Failure of kidney to produce erythropoietin.
to what kidney function test is the anemia frequently proportional? (anemia due to renal disease)
BUN.
What are the characteristics of anemia due to chronic disorders?
Often start out normocytic normochromic but then as condition continues become microcytic hyperchromic. Increased anemia, Increased BUN. Can look similar to Fe deficiency (Fe stores increased, serum Fe decreased, TIBC normal).
What is the common characteristic of ALL hemolytic anemias?
Increased RBC destruction
What type of RBC abnormality results in hereditary spherocytosis
Membrane abnormality-causes cell to be more permeable to sodium;
how does spherocytosis affect the shape and osmotic fragility of the RBC
makes them small and round rather than biconcave; and osmotic fragility is increased
What biochemical pathway involves the enzyme glucose-6-phosphate dehydrogenase(G-6-P-D)?
HMP shunt- to protect red cell (hemoglobin) from oxidation
hexosmonophosphate
What usually precipitates a hemolytic crisis in G-6-P-D deficiency?
Exposure to oxidizing drugs
What RBC inclusions does this deficiency produce?
Heinz bodies
What is the most unusual characteristic laboratory finding in ABO erythroblastosis of the newborn?
Spherocytes
what is the most unusual characteristic laboratory finding in AIHA
Positive Direct Coombs Test- extremely unusual in adult
How do PCH and PNH differ?
PCH: is extrinsic- have an antibody. Extracorpuscular defect.
PNH: intrinsic, acquired, sensitive to complement
In which condition is the Donath-Landsteiner antibody found?
PCH
What is the difference between an intrinsic (intracorpuscular defect) and an extrinsic (extracorpuscular) defect?
Intrinsic: Something in the cell (genetic) is causing hemolysis
Extrinsic: Something outside the cell is causing the hemolysis
What RBC abnormality is responsible for the formation of burr cells and thorn cells?
Membrane abnormalities
what globin chains are found in A2
2 alpha and 2 beta
what globin chains are found in F
2 alpha and 2 gamma
what globin chains are found in H
4 beta
what globin chains are found in BARTS
4 gamma
what globin chains are found in gower-1
epsilon
what globin chains are found in gower-2
zeta
Which ones are present only during embryonic development?
Epsilon and Zeta
What is the major hemoglobin of the newborn?
F
What hemoglobin is insoluble when reduced?
S
What hemoglobin is resistant to alkali?
F
What are the normal mobilities of hemoglobins A,C,F,S on hemoglobin electrophoresis at pH 8.6?
C-crawls, S-slow, F-fast, A-accelerates faster than fast
What is poikilocyte is the “common denominator” of peripheral blood smears of patients with hereditary hemoglobinpathies?
Target Cells
What is the specific amino acid substitution in hemoglobin S?
Valine substitutes in for Glutamic acid on # 6 position on alpha chain
what is the specific amino acid substitution in hemoglobin C
lysine substitutes for glutamic acid on 6 position in beta chain
What are the clinical manifestations of sickle cell anemia?
Frequent crises like aplastic and thrombotic crises, osteomyelitis, sickled cells, decreased osmotic fragility
What is the best test to use to differentiate sickle cell anemia and sickle cell trait?
Hg Electrophoresis
What does the peripheral blood smear usually show in sickle cell trait?
Occasional Target Cell
What are the characteristics of Hemoglobin C disease?
Target cells, rod shaped crystals, envelope cells, mild hemolytic anemia
Hemoglobin SC disease?
SC crystals (WASHINGTON MONUMENT) , positive tube solubility test, some sickle cells
Why does the hemoglobin combinations of S and D create a problem in the lab diagnosis of hemoglobinpathies?
Migrate together, alkaline pH S & D migrate together, further testing
What does the peripheral blood smear usually show in IDA?
Microcytic hypochromic
Polychromasia
NRBC
What does the serum iron and TIBC show in IDA
Serum iron-decreased
TIBC- increased
Define: Chlorosis
Green coloration of skin in hypochromic anemia
Define: Favism
G6 PD deficiency
Define: Koilonychia
spoon shaped nails found in iron deficency
Define: Pica Syndrome
Eating weird stuff
What are some causes of IDA?
Chronic bleeding, hookworm infection, menstrual problems, bleeding ulcers
What is the specific causes of the thalassemias?
Decreased rate of synthesis of either the alpha or beta chain. Abnormal one can’t keep up level of synthesis. So normal A could not be made
What is another name for beta thalassemia?
Cooley’s Anemia, Mediterranean anemia.
What hemoglobins are increased in thalassemia major? Why are they increased?
Can’t make beta chain- increases A2(alpha 2 and delta 2) and F(alpha 2 and gamma 2)
Define: Bart’s disease
Homozygous alpha thalassemia
Define: Cooley’s Trait
Beta thalassemia minor
Define: Fanconi’s anemia
Congenital Aplastic Anemia
Define: Hemoglobin H disease
Heterozygous alpha thalassemia
What are the characteristics of sideroblastic anemia?
Microcytic hypochromic, increased iron stores, increased ringed sideroblast
What is the RBC inclusion most frequently associated with lead poisoning?
Basophilic Stippling
What blood cell parameters are increased in polycythemia vera?
WBC
RBC
Platelets
What is the cause of secondary polycythemia?
Overproduction of erythropoetin
What parameters are increased in secondary polycythemia ?
Increased HGB
Increased HCT
Increased RBC count
How do hemachromatosis and hemosiderosis differ?
Both involve deposition of excess iron. Hemosiderosis is in the normal cells of the liver, spleen. Hemochromatosis is deposited in functional cells where they shouldn’t be placed causing tissue damage.
(Tissue damage is the most important to remember here)
What are some possible causes of relative polycythemia
Severe burns
Severe stress
Dehydration
