Hematopoietic and Lymphoid System Disease

Question 1

Primary Erythrocytosis

Answer 1

Abnormal proliferation of myeloid stem cells from red marrow, but normal/low levels of erythropoietin from kidneys
Idiopathic; from hyperplasia/neoplasia of erythroid tissue
Can sometimes accompany hyperplasia/neoplasia of bone marrow, which results in proliferation of all cell types

Question 2

Secondary Erythrocytosis

Answer 2

Increased RBC levels from increased erythropoietin from kidneys

• Appropriate Secondary Erythrocytosis
  
  • Associated with chronic systemic hypoxia
  • E.g. high altitudes, heart disease, chronic lung disease
• Inappropriate Secondary Erythrocytosis
  
  • Associated with tumors secreting excess erythropoietin
  • E.g. hepatoma, renal cell carcinoma

Question 3

Hereditary Spherocytosis

Answer 3

Intrinsic Hemolytic Anemia
Autosomal dominant
RBC cytoskeleton abnormality
RBCs become spherical shaped, but retain ability to carry oxygen(?)
Susceptible to damage and early destruction resulting in splenomegaly + hepatomegaly
Results in anemia which results in hyperplasia of bone marrow

Question 4

Sickle Cell Anemia

Answer 4

Intrinsic Hemolytic Anemia
Autosomal recessive
Hemoglobin has a substitution in one of its amino acids, causing it to take on a deformed shape; this further deforms the RBC into a “sickle” shape
These RBCs have a tendency to stick to the walls of the vessel, leading to inflammation, fibrosis, hypoxia, and infarction
Leads to hyperbilirubinemia which leads to gall stones
Leads to splenomegaly

Question 5

Thalessemias

Answer 5

Intrinsic Hemolytic Anemia
Heterozygous = moderate sx (severe growth retardation, splenomegaly, hepatomegaly)
Homozygous = severe sx (severe hypoxia, stillborn infant, death)

Question 6

Chronic Myelocytic Leukemia

Answer 6

Insidious onset mostly in adults
Possibly caused by germ cell mutation
Sx: anemia, blood clotting disorders, splenomegaly, lymphadenopathy, night sweats, weight loss

Question 7

Acute Myelocytic Leukemia

Answer 7

Usually affects those <50 years old

Possible causes: congenital, down syndrome, toxins, chemotherapy, radiation

Question 8

Acute Lymphocytic Leukemia

Answer 8

Mostly in children ~4 years old

Associated with: mature b-cells, immature t-cells