Clin Path/Transfusion Medicine Flashcards
Hematopoiesis
Production of all blood cells
Regulated by poietins, colony stimuli, interleukins
Erythropoiesis
Production of RBCs
stem cells → erythroblasts → reticulocytes → erythrocytes
Regulated by EPO which is regulated by blood O2 levels in kidneys
*HYPOXIA stimulates EPO
takes 1 week for RBC maturation
Thrombopoiesis
Production of Platelets
Stem cells → megakaryocyte → pieces of cytoplasm become platelets
Can take 1 week for produciton
Leukopoiesis
Production of WBCs
Granulocyte = neutrophils, eosinophils, basophils
Agranulocytes = lymphocytes, monocytes
RBC structure
Contains: H2O, Hb, Bi concave disc shape that creates more membrane for O2/CO2 diffusion
Lacks: Nucleus, mitochondria, ribosomes
K9 Lifespan: 120 days
Fel Lifespan: 68 days
CBC Values
vHb - Hemoblobin
HCT
MCV: Mean corpuscular vol; RBC avg size
MCH: Mean corpuscular Hb; Avg wt of Hb in RBC
MCHC: MCH concentration; Avg density of Hb in RBC
RDW: Red Cell Distribution width; EBC size variation
Retic %: Calc # can be overestimated w/ anemia
Absolute Retic count: # of immature RBCs; used to characterize anemia regen vs nonregen
Senescene
RBC aging process
1% of old RBCs removed daily via intravascularly or extravasclularly
Oxidative Stress (free radicals) contribute to rapid RBCs aging/destruction
-exacerbated by dz/toxins
Intravascular vs Extravascular Hemolysis
Intravascular: accounts for 10%, Hb released into blood stream → hemglobinemia → excess unconj Hb in plasma → eliminated by kidneys
Extravascular: 90% of RBC destruction via macrophages in spleen into amino acids, iron, and heme (from Hb)
-AA recycled by Liver
-Iron to bone marrow
-Heme broken into free or unconj bilirubin
Pathophysiology of Icterus
-Excessive RBC breakdown → excessive unconj bilirubin in plasma
-Unconj bilirubin exceeds Livers ability to conjugate → desposits to tissues (PRE-hepatic)
-Liver dz/dysfunction cannot handle processing unconj. bilirubin → buildup
- Bilirubin obstruction → conj bilirubin backs up into blood stream then tissues (POST- hepatic)
“spur cells” RBCs with blunt finger like projections
Injury via RBC damage traveling thru vasculature or fragile from iron deficiency
Liver dz, DIC, vasculitis
Spherocyte; more disc shape than biconcave, smaller, more dense lacking central pallor
IMHA; regenerative
Oxidative injury
Coral snake
Schitocytes; RBC fragments
mechanical injury to erythrocytes, turbulent blood flow
-Vascular abnormalities; DIC, vasculitis, PSS, hemangioma
Echinocytes “Spur cells” (tiny sun)
Drugs; chemo agents, furosemide
Renal dz; glomerulonephritis
Snake envenomation
Reticulocytes; immature RBCs. Lg amounts of RNA form dark blue clumps/strands
Bone marrow respone to anemia
Ghost Cells; pale RBCs due to loss of hemoglobin thru intravascular hemolysis
-IMHA
-Oxidant injury
-Snake envenomation
Basophilic stippling; numerous small blue punctuate stippling in RBCs
-Regenerative Anemia
-Lead poisoning
Heinz bodies; dense granuel on the edge of RBC caused by oxidative injury causes hemoglobin to precipitate
Propofol; acetaminophen in cats
toxins; Onion, zinc in dogs
anticoagulant rodenticide
Skunk musk
Howell- Jolly bodies; small round dark purple dots (nucleus remnants) within RBCs
Regenerative anemia
impaired splenic function (corticosteroids/splenectomy)
Nucleated RBC - most mature nucleated RBC
present in strongly regenerative anemias
Band Neutrophil; immature neutrophils
↑ bands present = left shift with acute or severe inflammation
Toxic neutophilic change
