First Aid - Hematology Flashcards
Dense granules of platelets contain..
ADP and Calcium
Alpha granules of platelets contain…
vWF and fibrinogen
Where is 1/3 of platelet pool stored?
spleen
Hypersegmented polys =
folate/b12 deficiency
increased band cells means…
increased myeloid proliferation (in repsonse to things like bacterial infections or CML)
Which cytokine activates macrophages?
IFN-gamma
Important macrophage cell marker
CD14
Functions of eosinophils
Anti-helminthic
Antigen-antibody opsonin phagocytosis
histaminase and arylsulfatase production to limit mast cell degranulation effects
What do basophils secrete to mediate allergic reactions?
heparin, histamin, leukotrieneds
Important B-cell markers
CD19, CD20
What are all the cells that act as APCs?
Macrophages, Dendritic (langerhan cells, B-lymphocytes
Important T-cell markers
CD3, CD4, CD8
What is the costimulatory signal necessary for T-cell activation?
CD28
What are the markers for T-cell PRECURSORS
CD1a; CD2, 3, 4, 5, 7, 8
Which antibody isotype causes hemolytic disease of hte newborn
IgG
Hemolytic disease of the newborn is when…
Mom has preformed antibodies against a blood type that her new baby has.
What type of antigens are attacked in hemolytic disease of the newborn
Rh+ cells
A,B, AB –> usually only by type O mothers, who form IgG rather other bood type moms, who tend to form IgM
What is the hageman factor?
Factor XII in the intrinsic pathway
What does vWF act as a carrier protein for?
Factor VIII
What is thrombin time?
TT = rate of conversion of fibrinogen to fibrin. Different form PTT and PT
Where is Factor VIII synthesized and stored?
synthesized in liver; stored in endothelium
How does Vitamin K play into coagulation factors?
Vitamin K must be reduced by epoxide reductase before it can act as the cofactor for maturation of coagulation factors 2, 7, 9, 10, C, S.
(epoxide reductase is the enzyme warfarin inhibits
Factor V leiden mutation does what…?
makes factor V that is resistant to cleavage/inactivation by Protein C. = procoagulant state.
What does TXA2 do in coagulation?
decreases blood flow by vasoconstriction , increases platelet aggregation
What does ADP do in coagulation?
induces GP2b/3a expression on platelet surface
What is seen under a crystal violet stain
Heinz bodies
What are howell jolly bodies?
remnants of nucleus. found in RBCs
supposed to be removed from RBC by splenic macrophages - so if you’re asplenic… womp womp, no howell jolly body removal for you.
What do you think when you see erythroid precursors in liver or spleen?
Extramedullary hematopoiesis
What promotes extramedullary hematopoiesis
EPO
hyperplastic marrow cell invasion of extramedullary organs
Plummer-Vinson Syndrome
Triad of iron deficiency anemia, esophageal webs, atrophic glossitis
koilonhychia (spoon nails)- where do you see it?
IRON DEFICIENCy
alpha-thalassemias - Asians vs Africans
Asians are Cis
Africans are trans
Alphat thalassemia - all the gene cominations
1-2 deletiosn = no anemia
3 = HbH disease (beta tetramers)
4 gene deletions = HbBarts (gamma tetramers) incompatible with life. hydrops fetalis
What is the genetic abnormality with beta thalassemia?
mRNA splice site point mutation = mrNA processing screw up
Why is beta thal asmptomatic at birth?
HbF for the next 6 months
What is beta thalassemia intermedia?
Its beta thal major that happens to have mild clinical presentation
How do beta thalassemics compensate for their messed up hemoglobin?
they make HbF (a2g2 for thal major) and HbA2 (a2d2) for thal minor
Special cells in beta thal major
target cells, schistocytes
What genetic mutation is beta thal intermedia associated with?
kozak sequence = mutaiton tha tprevents mRNA binding to ribosome
Clinical symptom difference between folate and B12 deficeincy
Folate deficienty = NO NEUROLOGIC SYMPTOMS
B12 = subacute combined degeneration leads to posterior column, lateral corticospinal and dementia symptoms)
Why folate deficeincy in alcoholics?
poor B9 ABSORPTION
What happens to your CBC when you treat B12 deficeincy?
give B12 supplement. Early spike in reticulocyes. older reticulocytes are slow to mature because they had a B12 deficient chidlhood. so you have a big proliferaiton of reticulocytes
Alcoholics and B12 vs Folate defiency
usually alcoholics dont’ get B12 , they gete B9 deficeincy
old people and B12 deficeincy
old people w/ chornic anemia w/o other identifiable causes
Old people = gatric catrophy = low H+ = low release of B!2 from food.
What is haptoglobin?
binds free hemoglobin to prevent renal excretion
What happens to haptoglobin in hemolytic anemias?
drops because hemolysis produces so much Hb the haptoglobin can’t handle it.
Explain the blood smear appearance of anemai of chronic disease
starts off as normocytic but over time you have less and less iron and you become microcytic and hypochromic.
Aplastic anemia presents as…
triad of severe anemia, thrombocytopenia and absent stem cells in marrow
Is there splenomegaly in aplastic anemia?
no
Marrow tap for aplastic anemia
dry. normal cell morphology but hypocellular marrow with fatty infiltration.
low reticulocyte count
Distinction of aplastic anemia from myeloplastic syndromes?
Marrow tap is dry in aplastic anemia.
Where are haptoglobin/Hemoglobin complexes cleared?
Liver
What is pure RBC aplasia associated with?
No RBC but normal WBC and Plateets associated with 1) Thymoma 2) lymphocytic leukemia. Can result from PArvo B19
General principle of inheritance patterns with protein mutations.
Structural protein defects = dominant (ankyrin in spherocytosis)
Enzymatic defects = REcessive (G6PD)
INheritance pattern of Hereditary spherocytosis
Autosomal dominant
Defect in hereditary spherocytosis
ankyrin, band 3, spectrin mutaitons
defective cytoskeleton = loss of plasma membrane = spherocytosis
Clinical findings of hereditary spherocytosis
Splenomegaly. Increased risk of aplastic crisis w/ Parvo B19, pigmented gallstones, jaundice and anemia
Diagnostic testing for hereditary spherocytosis
positive osmotic fragility test
Increased MCHC
Treatment of hereditary spherocytosis
splenectomy - RBCS work find its jsut he spleen keeps clearing them cuz their ugly.
Inheritance pattern of G6PD
X-linked recessive
What triggers hemolysis in G6PD?
Oxidant stresses like:
Sulfadrugs = sulfonamids, antimalarials, bactrim
infections
Fava beans