pathologic RBC forms

Question 1

spherocytes

Answer 1

herediary spherocytosis or autoimmune hemolysis

Question 2

target cells

Answer 2

HbC disease, asplenia, liver disease, thalassemia
liver disease causes less LCAT–> incr cholesterol: phospholipid ratio –> target cell
asplenia: without spleen, you don’t clear weird cells.
all of these because of a high ratio of membrane to hemoglobin content.

Question 3

schistocytes

Answer 3

DIC, TTP/HUS, traumatic hemolysis

Question 4

heinz bodies: give some pathophysiology too

Answer 4

oxidation of hemoglobin sulfhydryl groups cuases denatured hemoglobin precipitation and phagocytic damage to the RBC membrane (bite cells). heinz bodies are visualized with special stains, like crystal violet. seen in G6PD deficiency. heinz-like bodies also seen in alpha-thalassemia

Question 5

acanthocyte

Answer 5

(spur cell). very spike-y looking cell. seen in liver disease, abetalipoproteinemia

Question 6

basophilic stippling

Answer 6

alcoholism, anemia of chronic disease, thalassemias, lead poisoning

Question 7

bite cell

Answer 7

G6PD deficiency because the spleen is removing parts of the RBCs with precipitated hemoglobin (heinz bodies). G6PD becomes evident under oxidative stress.

Question 8

macro-ovulocyte

Answer 8

megaloblastic anemia, marrow failure

Question 9

ringed sideroblast

Answer 9

sideroblastic anemia. excess iron in mitochondria = pathology
causes: congenital sideroblastic anemia (ALAS deficiency), lead poisoning (ALAD and ferrochelatase inhibition), alcoholism (mitochondrial poisoning), or vitamin B6 deficiency (necessary cofactor for ALAS; often seen with isoniazid treatments).

Question 10

how does hematopoeisis occur?

Answer 10

CD34+ lymphocytes differentiate into myeloid stem cells and lymphoid stem cells. myeloid become: megakaryoblasts (megakaryocytes), monoblasts (monocytes), myeloblasts (eosinophils, basophils, neutrophils), erythroblast (RBCs).
lymphoid stem cells become b lymphoblast (naive B cell, then plasma cell) or t lymphoblast (naive T cell, then CD8 or CD4 T cells)

Question 11

What are some differences between causes of neutropenia and lymphopenia?

Answer 11

neutropenia- low neutrophils. seen with drugs, severe infection (like gram negative sepsis)
lymphopenia: low lymphocytes. seen with ionizing radiation, high cortisol state (causes apoptosis), AIDS, DiGeorge, autoimmunity

Question 12

causes of neutrophil leukocytosis. what is the marker for immature neutrophils?

Answer 12

bacterial infection or tissue necrosis that releases marginated pool of neutrophils and increases release from bone marrow. immature cells characterized by decreased Fc receptors (CD16).
or, high cortisol state- also impairs leukocyte adhesion

Question 13

lymphocytic leukocytosis: casues

Answer 13

viral infections, bordatella pertussis. in pertussis, bacteria produce a lymphocytosis-promoting factor which blocks circulating lymphocytes from leaving blood to enter the lymph node. infectious mononucleosis can do this too.

Question 14

Causes of infectious mononuleosis? what is affected?

Answer 14

usually EBV; sometimes CMV.
EBV infects the oropharynx, liver (elevated liver enzymes and hepatitis), B cells (potential complication- EBV dormancy in B cells increases risk of recurrance and B-cell lymphoma, esp. in immunocompromised.

Question 15

What happens with the T cell response to infectious mono? Why? Include anatomy

Answer 15

1. LAD from t cell hyperplasia in the lymph node paracortex.
2. Splenomegaly from t cell hyperplasia in the periartierial lymphatic sheath
3. high WBC count with atypical lymphocytes in the blood.