Ch. 5 - Normocytic anemia with Intravascular Hemolysis Flashcards
Is PNH congenital or acquired?
acquired
What is absent in PNH?
GPI
What does GPI do?
connects DAF and MIRL to the cell membrane of RBCs, platelets, and WBCs
What protects RBCs against complement by inhibiting C3 convertase?
DAF
PNH is due to (blank) mediated damage
complement
IN PNH intravascular hemolysis happens (daily/once in a while)
once in a while, hence paroxysmal
What triggers complement activation in PNH?
shallow breathing during sleep causes mild acidosis leading to complement activation
What two things are seen in the urine and one thing in the blood first thing in the morning with PNH?
HemoglobinemiaHemoglobinuriaHemosiderinuria
What is used to screen for PNH? What is used to confirm the Dx?
sucrose test used to screen; confirmation is acidified serum test or flow for lack of CD55
Main cause of death in PNH is thrombosis of what three veins?
hepatic, portal, or cerebral
What complications arise from PNH?
iron def. anemia and AML in 10% of the cases
G6PD def. is an x-linked rec. disorder that causes a reduced (blank) of glutathione
half life
What oxidative stress are RBCs routinely exposed to>?
hydrogen peroxide
What is needed to reduce oxidized glutathione?
NADPH
Which variant of G6PD def. is the mild form?
African
Which variant of G6PD def. is the severe form?
Mediterranean
What is the reason for the high carrier frequency of G6PD def. in both populations?
protection against malaria falciparum
In G6PD def., oxidative stress precipitates Hb as (blank) bodies
Heinz bodies
What are some notable causes of oxidative stress?
infections, drugs (sulfa and primaquine and dapsone), and fava beans
Removal of Heinz bodies from RBCs by splenic mac’s results in (blank) cells
bite
G6PD def. causes what type of hemolysis?
intravascular
WHat are the two symptoms that normally present a few hours after exposure to oxidative stress?
back pain and hemoglobinuria
What is used to screen for G6PD def. ? What is used to confirm the Dx?
Heinz stain to screen, enzyme studies to confirm
When are enzyme studies done to confirm G6PD def. ?
weeks after the last episode so the enzyme levels arent depleted.
IgG mediated autoimmune hemolysis is (warm/cold) agglutination
warm agglutination
IgG mediated IHA results in (intra/extra)vascular hemolysis
extravascular by the spleen
Where in the body does warm agglutination ocurr
in the core ie not the fingers
What finding on peripheral smear do you see for warm IgG mediated IHA?
spherocytes!
What diseases is IgG mediated IHA associated with?
SLE, CLL, and PCNs that can bind to RBC membrane and be recognized by the IgG as the drug-membrane complex
What are the Tx for IgG mediated IHA?
stop the drug thats causing itIVIGsplenectomy
IgM mediated IHA involves (intra/extra)vascular hemolysis
extravascular
IgM mediated IHA is (warm/cold) aglutination and happens where in the body?
cold; fingers
What serves as a opsonin for splenic macs in IgM medated IHA? How does this present on peripheral smear?
C3b is the opsonin leading to spherocytes
What leads to intravascular hemolysis in IgM mediated IHA?
extreme activation of complement
What two infections can cause IgM mediated IHA?
Mycoplasma pneumonia and infectious mono
What is the used to Dx IHA>?
Direct or indirect Coomb’s test; direct is the most important
Direct Coombs test confirms the presence of (blank)
Ab or complement coated RBCs in the pt serum
Indrect Coomb’s test confirms the presence of (blank)
Abs in the pt serum that will bind to TEST RBCs.
(blank) is a process that occurs with diseases like TTP-HUS, DIC, and HELLP, and is an intravascular hemolysis as RBCs pass through small blood vessels with microthrombi
microangiopathic hemolytic anemia
(blank) cells are seen on peripheral smear with prosthetic heart valves, aortic stenosis, and other causes of microangiopathic hemolytic anemia
shistocytes
Malaria causes what type of hemolysis?
intravascular
T/F: malaria causes extravascular hemolyssi
true, with splenomegaly. Not as much though as intravascular.
Parvovirus b19 infects RBCs and temporarily haults (blank)
erythropoiesis
Parvovirus b19 infections lead to severe anemia in the setting of what preexisting condition?
marrow stress; ie sickle cell anemia
Aplastic anemia presents with (mono/pan)cytopenia
pancytopenia and low RETC
What are the causes of aplastic anemia?
drugs, chemicals, viral infections, autoimmune damage
A biopsy of someone with aplastic anemia would show what of their bone marrow?
empty, fatty marrow
What drugs are given to correct aplastic anemia?
GM-CSF, G-CSF, immunosppression, and bone marrow transplant
Myelophthistic processes present with decreases in what cell lines?
ALL OF THEM