Topic 2 - Blood Disorders Flashcards
Where do one third of the body’s thrombocyte reserves remain?
In the spleen in reserve.
What are the three essential plasma proteins?
Albumin - maintaining blood pressure/volume
Globulin - Transportation of bilirubin, lipid and steroids
Fibrinogen - Inactive form of fibrin, necessary for blood clotting.
What volume of blood is in a healthy person? What should the formed part to plasma ratio be?
4-6 L in healthy adult. Approximately 45% is blood cells and 55% is plasma.
All formed elements of blood (with the exception of lymphocytes) derive from which stem cell?
Myeloid stem cell.
What is a CBC? What are its limitations?
A complete blood count is used to determine the number of RBCs, WBCs, and Platelets per unit of blood.
Cannot show abnormalities in cells present, a blood smear is needed for this.
What is a WBC?
A white Blood Count is a measure of the relative percentages of the individual WBC type.
What is a MCV? What kinds of things can it diagnose?
A mean corpuscular volume can determine the volume of the average RBC. Can diagnose megaloblastic or microcytic anemia.
What are the downstream effects of long-term anemia?
Long-term reduction to oxygen capacity can lead to tissue hypoxia and compensatory mechanisms to to restore tissue oxygenation. Such as:
–> Increased heart rate, cardiac output, and circulatory rate
–> preferential blood flow to vital organs.
What would a mean corpuscular hemoglobin concentration or mean cell Hb Concentration (MCHC) be used for?
To test for Hb concentration of RBCs present
Why would one test for the percentage or reticulocytes present?
To show health on bone marrow and determine how many new RBCs are being produced.
What is the definition of anemia?
A reduction in the total number of erythrocytes or a decrease in the quality or quantity of hemoglobin.
Why might erythrocytes be microcytic?
Because there is a shortage of hemoglobin.
What kind of anemia is macrocytic and normochromic? Why?
Anemia caused by folate or b12 deficiency - pernicious anemia
Cells are unable to undergo DNA replication step of mitosis. Become large in preparation of cytokinesis but are never able to separate due to lack of DNA replication.
Which three categories can the effects of anemia be sorted into?
- Manifestations of impaired oxygen transport and the resulting compensatory mechanisms
- Reduction in RBC indices and hemoglobin levels
- Signs and symptoms associated with the process that is causing anemia
How do the kidneys respond to tissue hypoxia?
Releasing EPO and increasing renin-aldosterone –> salt and H2O retention
Increased stroke volume due to tissue hypoxia can lead to which cardiovascular complications?
Hyperdynamic circulation can lead to cardiac murmur and heart failure.
How does long-term hypoxia affect the liver?
fatty changes might occur - such changes might also occur in the heart and kidneys
What is BPG? What is its relevance to anemia?
A molecule and decreases Hb’s affinity for oxygen. Increased levels in those with anemia.
What are the symptoms of mild anemia?
Usually none, but elderly individuals with CV or pulmonary disease may have symptoms.
What are the symptoms of mild to moderate anemia?
Fatigue, generalized weakness, loss of stamina, tachycardia and exertional dyspnea
What are the symptoms of moderate to severe anemia?
–> Orthostatic and generalized hypotension, vasoconstriction, pallor.
–> Tachycardia, dyspnea
–> Angina pectoris, heart failure, transient murmurs
–> Intermittent claudation, night cramps
–> Headache, lightheadedness, and faintness
–> Tinnitus
Which kind of anemia are usually accompanied by jaundice? Why?
Hemolytic anemias - heme breaks down into bilirubin faster than the liver can metabolize it.
Which kind of anemia is usually accompanied by petechia and purpura? Why?
Aplastic anemia - decreased platelet function leads to slower healing of micro tears under skin.
What is aplastic anemia?
A disorder of the pluripotent bone marrow stem cell - leads to a reduction of all three hematopoietic cell lines (aka pancytopenia)
What kind of anemia presents as normocytic and normochromatic?
Aplastic anemia.
Weakness, fatigue, pallor, increased susceptibility to infection, and petechia, and bleeding from mucous membranes is characteristic of what kind of enemia?
Aplastic
What are the three kinds of aplastic anemia?
Primary acquired, secondary acquires (chemo, radiation, toxic chemical exposure, some mycobacteria or virus), and genetic alterations (fanconi anemia)
What is Fanconi anemia?
Aplastic anemia (pancytopenia) due to DNA repair defects.
How is aplastic anemia diagnosed?
- Patient history
- CBC - low and reticulocytes should be close to 0
- Bone marrow biopsy - hypocellular marrow replaced by fat, absence of progenitor cells.
How is aplastic anemia treated?
- Manage symptoms (transfusion of PRBC or platelets)
- Bone marrow transplant (80-85% curative rate)
- Without a suitable donor - immunosuppression therapy
Why is it important to take a patient history when you suspect aplastic anemia?
A history of cancer treatment, chemical exposure, or infection can indicate secondary aplastic anemia.
What is the risk when putting a person with 1° aplastic anemia on immunosuppresants?
They are already immunocompromised - they will be highly susceptible to infection.
What kind of RBC, WBC, and platelet indices would be expected in an individual from anemia of chronic renal failure?
RBC - low due to lack of EPO
WBC - not affected
Platelet - not affected
How would the blood cells of a person with pernicious anemia look?
–> RBCs will be macrocytic
–> Granulocytes are hypersegmented.
–> Platelets are decreases and increased megaloblasts
Because blast cells are unable to replicate DNA to complete mitosis
What might cause B12 deficiency?
–> Damage or atrophy of parietal cells
–> Resectioning of the stomach or small intestine
—> chronic malabsorption in severe Chron’s or AIDS
What might cause folate deficiency?
Dietary deficiencies, alcoholism, cirrhosis, pregnancy, or infancy.
What are some signs and symptoms of vitamin b12 or folate deficiency?
Pedal edema, dyspnea, tachycardia, heart congestion, glossitis, weight loss
Irritability, memory impairment, perversions of smell, taste, and vision, depression, disruption of sleep, personality changes.
What is megaloblastic madness?
Paranoia, delusions, hallucination, and cognitive dysfunction associated with vitamin b12 or folate deficiency
How is folate or vitamin b12 deficiency treated?
- Recognize that megaloblastic anemia is present
- Ascertain which vitamin is deficient and supplement
- Diagnose the underlying disease or mechanism responsible
What kind of anemias are characterized by normocytic and normochromic RBCs, with an increases number of reticulocytes?
Hemolytic anemias
Which kind of anemias are associated with normal WBC count, varied platelets, and microcytic hypochromic RBCs?
Iron deficiency anemia (IDA)
What are some causes for IDA?
Increased demand (pregnancy), insufficient uptake, decreased absorption or chronic blood loss, or genetic conditions (Iron Refraction IDA)
What are some specific symptoms of IDA?
–> Pallor of skin or mucous membranes
–> Koilonychia
–> Glossitis
–> Pica
How do you diagnose for IDA?
- Check RBCs #
- Iron studies: Serum iron, % saturation, and ferritin will be low. Total Fe Capacity of transferrin will be very high (Bc three’s nothing for it to bind to).
What is the normal level of iron % saturation?
33%
How can IDA be treated?
–> oral supplement of iron salts (Iron sulphate is most common)
–> If this doesn’t work, intravenous ferric gluconate, and determine and treat the underlying cause.