Ch 42: Blood disorders Flashcards
What is anemia?
Reduction in the number of RBC’s, hemoglobin or hematocrit.
What is the most common cause of anemia in adults?
GI bleeding
Common causes of iron-deficient anemia?
Inadequate iron intake caused by: Iron-deficient diet Chronic alcoholism Malabsorption syndromes Partial gastrectomy
Rapid anabolic activity caused by:
Pregnancy
Adolescence
Infection
What are common causes of vitamin B12 deficiency anemia?
Dietary deficiency Failure to absorb vitamin B12 from intestinal tract as result of: Partial gastrectomy Pernicious anemia Malabsorption syndromes
What are common causes of aplastic anemia?
Exposure to myelotoxic agents: Radiation Benzene Sulfonamides Insecticides
Adults usually have between ____ g of iron in the body
2 and 6
Foods rich in iron
Red meat Organ meat Egg yolks Kidney beans Leafy green vegetables Raisins
What is the best way to administer an IM injection of iron?
Z-track
What is a function of vitamin B12?
Activate enzymes that move folic acid into the cell where DNA synthesis occurs.
How does vitamin B12 deficiency cause anemia?
It inhibits folic acid transport and reducing DNA synthesis in precursor cells.
The precursor cells undergo improper DNA synthesis and increase in size.
Only few are released from the bone marrow.
This type of anemia is called megaloblastic or macrocytic anemia because of the large size of the abnormal cells.
What patients are at risk for Vitamin B12?
Vegetarians or diets lacking dairy products.
Anemia resulting from failure to absorb vitamin B12 is called:
pernicious anemia
What is the cause of pernicious anemia (besides failing to absorb vitamin B12)?
Deficiency of intrinsic factor (secreted by the gastric mucosa), which is needed for intestinal absorption of vitamin B12.
What is a main sign of pernicious anemia?
Beefy red tongue (also known as glossitis), fatigue, and weight loss.
Also may have poor balance and paresthesias because B12 is needed for normal nerve function.
What foods are high in vitamin B12?
Animal proteins
eggs
dairy products
What is a Shilling test?
Measures amount of vitamin B12 in urine after patient is given an oral dose of radioactive vitamin B12.
If the patient does not absorb the radioactive B12 because of the pernicious anemia, it cannot get into the urine.
What is aplastic anemia?
Deficiency of circulating RBC because of failure of bone marrow to produce these cells.
aplastic (a=no plastic=build/shape)
Difference between Folic Acid deficiency and B12 deficiency?
B12 has neurological symptoms since B12 is needed for nerve function.
What is a pluripotent stem cell?
Immature precursor cell for red blood cells.
Aplastic anemia can occur alone, but usually occurs with _______
leukopenia and thrombocytopenia
What is leukopenia?
reduction in white blood cells
What is thrombocytopenia?
Reduction in platelets.
What is pancytopenia?
Deficiency of WBC, platelets and failure of bone marrow to produce RBC.
What is the most common hereditary form of aplastic anemia?
Fanconi’s anemia
