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