Hematologic Pathology Flashcards
platelets
cytoplasmic fragments of megakaryocytes
fxn: stop bleeding
lifespan = 8-9 days, 30% of numbers are on reserve in spleen
eyrthrocytes
RBCs
most numbers
life span: 3-4 months in circulation
large surface area (surface:volume) so they can quickly pick up and dump oxygen
flexible: can get into small capillaries
where are WBCs produced?
Bone marrow, lymph nodes and spleen
types of WBCs
- neutrophils
- lymphocytes
3, eosinophils - basophils
- monocytes
neutrophils
45-70%
actively phagocytic cells (fights foreign invaders)
dominate in acute inflammation and bacterial infections
lymphocytes
35-40%
long living, predominate in WBC of children
rotation between circulation and lymph nodes
predominate in a viral infection
eosinophils
5-10% (MINOR)
when they are high: NAACP
N= neoplasm A= allergies A= airway disease C=connective tissue disease P= parasites
basophils
3-7% (LEAST common)
allergic reactions
histamine and heparin release
monocytes
3-5%
actively phagocytic cells
become macrophages when they move from the blood to the tissues
hematopoietic stem cells
progenitor cells that are found in bone marrow
common “ancestor” for all blood cells, growth factors/hormones differentiate
thrombopeotin
stimulates platelet production
produced by liver, kidney, skeletal muscle, bone marrow
low platelet count stimulates thrombotic production
hormones that stimulate WBC production
G-CSF
GM-CSF
IL3
what hormone stimulates RBC production?
erythropoeitn
Erythropoetin
RBC production hormone
stimulated for release by kidney
what stimulates eruthropoetin release from kidney?
low peripheral blood O2
problematic bc may promote blood viscosity (decreasing blood flow rate)
hypoxia can have other causes (such as smoking) that could be harmed by increased viscosity
most important white cells disorders
malignancies
spleen functions
identification and removal of tagged cells (cells with Igs)
storage of platelets
removal of red blood cells (damaged or old)
what causes damage to the spleen
mononucleosis
liver disease
cancer
if damaged, it won’t weed out potential invaders or rupture during trauma
sequelae if spleen is removed
immunocompromised
especially sensitive to encapsulated organisms (spleen is best at grabbing these) (meningitis nicesiaria, etc.)
cancer that starts in progenitors cells of WBCs
leukemia
When a progenitor cell becomes a leukemic cell:
maturation process is arrested (stops)
cell division is then accelerated and apoptosis is limited
resulting in many copies of immature cells
builds up in the bone marrow and crowd out the normal cells (eventually spread to other cells)
two categories of leukemia
- lymphotic or myeloid leukemia
2. acute or chronic leukemia
leukemias developing from lymphoid cell line
lymphocytic
leukemias developing from WBCs, RBCs, and platelet precursors
myeloid