Heme - Onc Flashcards
Intrinsic coagulation pathway
XII, XI, IX, VIII (IIa), —> X, II, Fibrinogen/fibrin, XIII
Reflected in PTT
Extrinsic coagulation pathway
VII –> X, II, Fibrinogen/fibrin, XIII
Reflected in PT
VitK coag factors
II, VII, IX, X
Anti: C, S
Anticoagulation
Protein C –> C* –S–> cleaves Va, VIIIa
Plasminogen –tPA–> plasmin –> cleave fibrin, destroy coag factors
Factor V Leiden
resists inhibition by protein C.
Heparin
Enhances antithrombin (cleave II, Xa).
Unfractionated: II, Xa
LMWH: Xa
vWF
binds GpIb (absence of = Bernard-Soulier syndrome).
Activated by ristocetin (no change in resposne in vW disease).
ADP receptor
Leads to increased GpIIb/IIIa on surface.
Blocked by clopidogrel, ticlopidine (AE neutropenia).
GpIIb/IIIa
Binds fibrinogen to crosslink plts.
Deficiency: glanzmann thrombasthenia.
Blocked by abciximab.
Paroxysmal nocturnal hemaglobinuria
CD55 and CD59 are absent.
Normally, they inactivate complement, thus complement-mediated hemolysis.
Tx: eculizumab.
Lead poisoning
Enzyme: ferrochelatase, ALA dehydratase.
Accumulated: protoporphyrin, delta-ALA
Sx: microcytic anemia, GI and kidney disease. Children (mental deterioration). Adults (HA, memory loss, demyelination).
Acute intermittent porphyria
Enzyme: Porphobilinogen deaminase.
Accumulate: porphobilinogen, delta-ALA, coporphobilinogen (urine).
Sx: painful abdomen, port wine-colored urine, polyneuropathy, psychological disturbances, precipitated by drugs, alcohol, starvation.
No cutaneous manifestation.
Tx: glucose, heme.
Porphyria cutanea tarda
Enzyme: uroporphyrinogen decarboxylase.
Accumulate: uroporphyrin (uroporphyrinogen III).
Sx: blistering cutaneous photosensitivity.
Most common porphyria.
Alkaline phosphatase (CML vs Leukamoid)
Leukamoid: increased.
CML: decreased.
Reed-Sternberg cells:
-Surface proteins
CD15, CD30
