IM Hematology Flashcards
What is the physiologic cause of hemolytic anemia in G6PD deficiency?
Reduction in glutathione levels in red cells
What is the inheritance pattern of G6PD deficiency?
X-linked recessive
What ethnicities is G6PD deficiency most commonly seen in?
African and Mediterranean
Name some drugs that are likely to lead to acute hemolysis in patients with G6PD deficiency?
Oxidative drugs such as primaquine, aspirin, dapsone, quinidine, sulfonamides, and nitrofurantoin
What is seen on peripheral blood smear that is consistent with a hemolytic episode of G6PD deficiency?
Heinz bodies and bite cells
Is thalassemia a macrocytic or microcytic anemia?
Microcytic
What ethnicity is alpha thalassemia commonly found in?
Southeast Asian and Chinese
What ethnicity is beta thalassemia most commonly found in?
African and Mediterranean
How many types of alpha thalassemia are there? What are they?
4 types: Carrier - 1 alpha gene deletion Minor - two alpha gene deletions Hb H disease - 3 alpha gene deletions Hydrops fetalis - 4 alpha gene deletions
What chromosome is the alpha gene found on?
Chromosome 16
What is the inheritance pattern of sickle cell anemia?
Autosomal recessive
At what age does sickle cell anemia begin to present? Why?
Around 6 months, when fetal hemoglobin is replaced with HbS.
What is the most common cause of death due to sickle cell anemia?
Acute chest syndrome
What is the definitive diagnostic study for sickle cell anemia?
Electrophoresis
What is the only pharmacologic agent that has consistently demonstrated improvements in episodes of pain and survival rates for patients with sickle cell anemia?
Hydroxyurea
What is the mechanism of action of hydroxyurea?
Increases production of hemoglobin F and reduces production of hemoglobin S
Why are patients with sickle cell anemia prone to infection by encapsulated organisms?
They have a dysfunctional spleen
What anemias a megaloblastic anemias?
Vitamin B12 deficiency and folate deficiency anemias
What is the most common cause of vitamin B12 deficiency anemia?
Strict veganism
What is the most common cause of vitamin B12 deficiency?
Pernicious anemia
What is pernicious anemia?
Autoimmune destruction of parietal cells resulting in decrease in production of intrinsic factor causing B12 deficiency
What is the pathophysiologic cause of neurologic symptoms in vitamin B12 deficiency anemia?
Accumulation of methylmalonic acid causes degeneration of the spinal cord
What type of anemia classically presents with koilonychia and pica?
IDA
Deficient activity of the plasma enzyme ADAMTS13 causes what hematologic disorder?
Thrombotic thrombocytopenic purpura
What is the classic pentad of symptoms associated with thrombotic thrombocytopenic purpura?
Fever, anemia, thrombocytopenia, kidney insufficiency, and neurological disturbances
Which microangiopathy is Shiga toxin-mediated and results after ingestion of undercooked ground beef contaminated with Escherichia coli?
Hemolytic uremic syndrome.
What is the most common pathologic fracture associated with multiple myeloma?
Vertebral fractures
A monoclonal protein spike on serum protein electrophoresis is commonly seen in _____?
Multiple myeloma
What protein is commonly seen in urine in multiple myeloma?
Bence Jones protein
What are the expected findings in radiographs of the skull in multiple myeloma?
Punched out lesions
What facial bone is associated with necrosis resulting from long-term bisphosphonate use?
Jaw.
What will a peripheral blood smear show in a patient with multiple myeloma?
Rouleaux formations
Hemophilia A results from deficiency of what clotting factor?
Factor VIII
Hemophilia B results from lack of what clotting factor?
Factor IX
What medication can be given to patients with hemophilia A to increase serum level of factor VIII?
Desmopressin acetate
What factor enhances platelet aggregation and adhesion?
Von Willebrand factor.
What is the inheritance pattern of hemophilias?
X-linked recessive
