Blood & Cancer Flashcards
Normal RBC & HBG for men?
RBC 5-6, HGB ~15
Normal RBC for Women?
RBC 4-5, HGB ~14
What bones produce RBCs in the older adult?
Ribs, Vertebrae, Sternum, Ilia
What would cause RBC number to increase?
Tissue hypoxia = stimulates growth inducers and differentiation inducers
What is the essential regulator of red blood cell production?
Tissue oxygenation
Anemia is common in what patient populations?
Cardiac failure, Lung diseases, high altitudes. (Low oxygen states!).
What hormone stimulates RBC production when oxygen levels are low?
Erythropoietin
Where is erythropoietin made?
90% in kidneys. 10% in other body tissues (liver).
What are the two effects of erythropoietin?
- Stimulate production of RBCs from stem cells
2. Develop more rapidly through erythroblastic stages
What are essential for maturation of RBCs?
Vitamin B12 and Folic acid.
both used in DNA synthesis
Decreased folic acid or B12 causes what two characteristics?
- Macrocytes - large, flimsy
- Have short life span
* Can carry oxygen normally!
What causes pernicious anemia?
Failure to absorb vitamin B12, usually caused by atrophic gastric mucosa.
Where is B12 stored? How long do that storage last?
Stored in liver. Anemias are seen 3-4 years after defective B12 absorption starts.
How many atoms of Iron does each hemoglobin molecule carry? How many molecules of oxygen?
4 iron atoms per Hgb molecule. 4 molecules of oxygen (total 8 atoms).
How is iron transported in the plasma?
Binds to protein to form transferrin.
In what form is iron stored in the cell?
Binds to protein to form ferritin.
Where is excess iron stored?
Mostly in the liver, some in the reticuloendothelial cells of bone marrow.
What is the maximum rate of iron absorption from GI system?
Only a few milligrams per day. Average loss of women is 1.3mg/day!
Is the body able to increase the rate of iron absorption?
Yes! When iron stores are depleted, can accelerate 5x normal.
RBCs contain cytoplasmic enzymes that do these 4 things:
- Maintain cell membrane
- Maintain transport of ions across membrane
- keep iron in ferrous form
- Prevent oxidation of proteins in RBCs
How is hemoglobin excreted?
iron is recycled for use in new RBCs. Proteins are excreted as bilirubin.
What type of anemia is seen in chronic blood loss?
Microcytic hypochromic anemia.
What causes megaloblastic anemia?
Lack of B12 or folic acid. Seen in atrophic gastric mucosa, intestinal sprue, or total gastrectomy.
What is hemolytic anemia?
Fragile RBCs that rupture easily, causing an extremely short lifespan.
What are two common types of hemolytic anemia?
- Sickle Cell Disease
2. Erythroblastosis Fetalis
What is the MAJOR side effect of anemia?
Greatly increased cardiac output! Also causes increased workload on heart.
What could cause acute cardiac failure in an anemic person?
Increased tissue demand for oxygen. ie - Exercise!
What is polycythemia vera?
RBC 7-8 and HCT 60-70%. Too many RBCs = viscous and plugging.
What is the hemodynamic effect of viscous blood?
Decreased venous return to heart, cancels out the increased blood volume = normal CO. BP often normal b/c body compensates!
Normal concentration of platelets?
150-450k
What is the role of glycoproteins on platelets?
Prevents adherence to normal endothelium but reacts to injured areas
What is thromboxane A2?
Vasoconstrictor, reacts with platelets to activate them during clotting process
What activates prothrombin activator? What is the next step in the process?
Activated Xa -> prothrombin activator -> prothrombin
What is the role of thrombin?
Enzyme that converts fibrinogen into fibrin fibers to form clot.
What electrolyte is required throughout the clotting process?
Calcium!
What two substances are made in the liver?
Vitamin K and fibrinogen
What activates the extrinsic pathway?
Trauma to the vascular wall or surrounding tissues come into contact with blood.
What activates the intrinsic pathway?
Trauma to the blood or exposure to endothelial collagen.
Where does the common pathway start?
With the activation of factor x.
Which is faster - the intrinsic or extrinsic clotting pathway?
Extrinsic.
The production of what substances are decreased when endothelial cells are damaged?
Prostaglandin and Nitric Oxide. Both usually inhibit plt aggregation and start of blood clotting.
What is the role of plasmin?
Digests fibrin fibers, fibrinogen, several clotting factors. Breaks down clot!
What activates plasminogen to create plasmin?
Tissue plasminogen activator (t-PA).
What patient populations are deficient in vitamin K and are at increased risk of bleeding?
Liver patients, obstruction of bile ducts, gastrointestinal disease preventing absorption.
What is the inheritance pattern of hemophilia?
Genetically transmitted, X-linked, recessive. Therefore usually only occurs in males.
What are the 5 major causes of thrombocytopenia?
- Decreased production in bone marrow
- Antibody destruction of plts
- Pooling of plts in spleen
- Thrombi consuming clotting factors
- Dilution of blood
If a clot forms in the venous system and breaks off it causes? What does it NOT cause?
PE. it does NOT cause stroke!
If a clot forms in the arterial system or left side of heart, where does it go?
Stroke.
What are two causes of thromboembolic conditions?
- Roughened endothelial surface
2. Slow blood flow
What causes DIC?
Endotoxins from bacterial sepsis.
In what form is iron stored in the cell? How is it trasnported?
Stored as ferritin. Transported as transferritin.
What is the MCV?
Mean corpuscular volume. Average size of RBCs in sample (determines microcytic vs. macrocytic)
What is a normal MCV?
80-96
What is MCHC?
mean corpuscular hemoglobin concentration. Determines color of RBCs. (hypochromic vs. hyperchromic)
What is a normal MCHC?
31-36
What is TiBC?
Total iron binding capacity. Higher numbers = not enough iron.
What is normal TiBC?
240-450
What is normal iron levels?
60-170
What is ferritin?
Storage of iron in the cell.
What is a normal ferritin level?
Male 12-300
Female 12-150
What causes microcytic hypochromic RBCs?
Iron deficiency anemia
What causes megaloblastic RBCs?
B12 deficiency anemia
What are the characteristics of hemolytic anemia?
High bilirubin, low hgb/hct, high reticulocyte count, high RDW
What is Virchow’s triad?
- Endothelial Injury
- Venous stasis
- Hypercoagulability
What medications do you use in athersclerosis?
Anti-platelets (Asa, plavix)
What medications do you use for venous stasis and Afib?
Anticoagulants
What are the phases of interphase? What happens during interphase?
G1, S, and G2.
DNA duplication, duplication of organelles
List the 4 phases of mitosis
- Prophase
- Metaphase
- Anaphase
- Telophase
What happens during metaphase?
Centromeres line up in the MIDDLE
What do cyclin, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors do?
Control the cell cycle and mitosis.
What is the P53?
Tumor suppression gene
What is carcinoma in situ?
Abnormal cells that have not breached the basement membrane. Known as pre-invasive and non malignant.
What are proto-onco genes?
They are genes that encode proteins that promote cell division. Normal in childhood, mutations can reactivate them.
What are the 6 cancer cell hallmarks?
- Immortality
- Resist apoptosis
- Evade growth suppressors (p53)
- Genomic instability
- Angiogenesis
- Uncontrolled proliferative signaling
What are the characteristics of transformation from normal cell to cancer cell?
Autonomy from cellular controls, lack contact inhibition, anchorage independent, and are immortal
What is the most common leukemia in children? Adults?
Children = ALL Adults = AML
When there are more than 30% lymphoblast in blood or BM, what is that diagnostic of?
ALL
Binucleate Reed-Steinburg cells are diagnostic of what type of cancer?
Hodgkin’s Lymphoma
What do you need to be careful of in Multiple Myeloma?
Kidney Function - can cause renal failure!
