Ch. 26: Alterations of Erythrocyte Function Flashcards
Which of the following is a description for the term anemia?
Increased white blood cell size
Increased erythrocyte number in circulating blood
Decreased erythrocytes in circulating blood
Decreased circulating platelets
Decreased erythrocytes in circulation blood
Anemia is a reduction in the total number of erythrocytes in the circulating blood or a decrease in the quality or quantity of hemoglobin.
Which of the following is NOT one of the common causes of anemia? Impaired production Blood transfusion Increased red cell destruction Severe bleeding
Blood transfusion
Anemia can be caused by impaired production of erythrocytes, blood loss, increased red cell destruction, or any combination of these.
Which of the following is characteristic of the megaloblastic anemias? Small cell size Decreased thickness Caused by increased folate Presence of macrocytes
Presence of macrocytes
Macrocytes are found. These are unusually large stem cells (megaloblasts) in the marrow that mature into unusually large stem cells (macrocytes) in the circulation. There is increased size, thickness, and volume with these cells.
Which of the following is a TRUE statement regarding pernicious anemia?
Rare form of megaloblastic anemia
Associated with end-stage type A chronic atrophic gastritis
It is of viral origin
Mean age of onset of 6 years
Associated with end-stage type A chronic atrophic gastritis
Pernicious anemia is due to the absence of intrinsic factor. It generally occurs in older adults with mean age of onset of 60 years. It is the most common form of megaloblastic anemia. It is autoimmune and is associated with end-stage type A chronic atrophic gastritis.
Which of the following is a TRUE statement regarding folate?
Dietary intake is about 50 to 200 mcg/day.
Pregnant women require less folate.
Folate synthesis takes place in the stomach.
Absorption of folate takes place in the stomach.
Dietary intake is about 50-200 mcg/day
Pregnant women require more folate. Folate synthesis takes place in the human intestine, and absorption occurs in the small intestine.
Which of the following is NOT a cause of microcytic-hypochromic anemia? Disorders of iron metabolism Disorders of porphyrin synthesis Disorders of globin synthesis Disorders of vitamin B12 absorption
Disorders of vitamin B12 absorption
Pernicious anemia is a macrocytic-normochromic anemia that results in an inability to absorb vitamin B12. The others are all causes of microcytic-hypochromic anemia.
Which form of anemia is caused by a deviation in mitochondrial metabolism? Iron deficiency Microcytic-hypochromic Sideroblastic Megaloblastic
Sideroblastic
Sideroblastic anemias are a heterogeneous group of disorders characterized by anemia of varying severity due to a deviation in mitochondrial metabolism. Iron deficiency anemia is the most common type of anemia worldwide, and is a type of microcytic-hypochromic anemia. Megaloblastic anemias are characterized by unusually large erythrocytes (macrocytes).
A person displays a reduction in red blood cells, white blood cells, and platelets. Which of the following is the most appropriate term for this condition? Aplastic anemia Erythropoietic hemochromatosis Myelodysplastic syndrome Sideroblastic anemia
Aplastic anemia
Aplastic anemia occurs with pancytopenia (a decrease in all three cell types). Myelodysplastic syndrome is a group of disorders that demonstrate hematopoietic stem cell dysfunction. Erythropoietic hemochromatosis is a condition with iron overload. Sideroblastic anemia is a disorder caused by a deviation of mitochondrial metabolism.
Which of the following is TRUE regarding posthemorrhagic anemia?
A healthy person can tolerate a loss of 2000 ml of blood.
It results in normocytic and normochromic anemia.
Hypertension may be present.
There is increased venous return.
It results in normocytic and normochromic anemia
Hemorrhage results in loss of red blood cells and volume. A healthy person can withstand the loss of 500 to 1000 ml without symptoms. If blood loss exceeds 2000 ml, this may result in severe shock, lactic acidosis, and death. It does cause a normocytic normochromic anemia. The signs include decreased venous return and hypotension.
Which of the following is the BEST definition for Fanconi anemia?
Caused by a defect in DNA repair
Caused by a defect in mitochondrial mechanisms.
Caused by a defect in porphyrin synthesis
Caused by a thymoma
Caused by a defect in DNA repair
Fanconi anemia is caused by defects in DNA repair. This anemia develops early in life and is accompanied by multiple congenital anomalies. Defects in mitochondrial mechanisms are consistent with sideroblastic anemia. Thymoma is associated with pure red cell aplasia. Defects in porphyrin synthesis are associated with microcytic-hypochromic anemia.
Which of the following is TRUE regarding autoimmune hemolytic anemias?
They are congenital disorders.
There are three types classified by the type of antibodies present.
They are caused by autoantibodies against erythrocyte antigens.
They are caused by intravascular hemolysis.
They are caused by autoantibodies against erythrocyte antigens
Autoimmune hemolytic anemias are caused by autoantibodies against antigens normally on the surface of erythrocytes. They are acquired disorders. The three types are classified by the optimal temperature at which antibody binds to erythrocytes.
Which of the following types of antibody is the most common form of autoimmune hemolytic anemia and affects individuals older than the age of 40? Warm antibody Cold agglutinin Cold hemolysins Warm hemolysins
Warm antibody
Cold agglutinin is less common and is mediated by IgM. It affects older women. Cold hemolysin is a rare disorder involving IgG and can result in massive intravascular hemolysis. There is no warm hemolysin. Warm antibody is IgG mediated, is the most common, and occurs in individuals older than age 40.
Which of the following is TRUE concerning drug-induced anemia?
It is a form of immune hemolytic anemia.
It is an allergic reaction against large molecular drugs.
Extravascular RBCs in the spleen and liver are removed by complement.
Anemia occurs within 1 week of infusion of drug.
It is a form of immune hemolytic anemia
Drug-induced hemolytic anemia is a form of immune hemolytic anemia from an allergic reaction against foreign antigens (antibiotics). Usually the drug is small molecular weight. Hemolysis is usually extravascular and opsonized RBCs are removed by phagocytes in the spleen and liver. Complement-dependent intravascular hemolysis may occur. This form of drug-induced anemia occurs 1 to 2 weeks after exposure to the antibiotic.
Which of the following is the appropriate term for the increase in red cell production? Anemia Hemolytic crisis Polycythemia Apoferritin
Polycythemia
Anemia is a decrease in the number of red blood cells. Hemolytic crisis is fulminate hemolytic anemia and can present with shock. Apoferritin is a protein implicated in altered iron metabolism.
Which of the following illnesses is the most common cause of aplastic crisis? Influenza Varicella zoster Human parvovirus B19 Leukemia
Human parvovirus B19
