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Flashcards in Red Blood Cell disorders Deck (26):
1

TACO

underlying cardiac/circulatory problems; responds to diuretics

2

TRALI

due to antibodies against white blood cells, leading to a breakdown of the walls of blood vessels in the lungs, allowing fluid to infiltrate the lungs; it does not respond to diuretics

3

Microcytic Anemias

Iron deficiency
Cu deficiency
Thalassemia
Anemia of chronic disease
Lead poisoning
Zinc toxicity
Sideroblastic anemia

4

spherocytes are seen in?

-hereditary spherocytosis
-warm autoimmune hemolytic anemia?

5

blister/basket cells are seen in?

-G6PD deficiency
-glutathione synthetase deficiency
-unstable hemoglobinopathies

6

Howell-Jolly bodies are composed of ___ and seen in diseases like___. They are indicative of ____

denatured DNA
hereditary spherocytosis s/p splenectomy
splenic dysfunction

7

Heinz bodies are made of ___ and seen in ___

-precipitated Hgb

8

Schistocytes are ___ and seen in ___

-fragmented RBC
-microangiopathic hemolytic anemias (HUS, TTP, possibly DIC)
-brute force trauma - malignant HTN, mechanical heart valves and pumps

9

TTP is due to:

deficiency of VWF cleaving enzyme (ADAMTS13)

10

Steps of B12 absorption

-B12+food, B12 released
-B12+salivary proteins (R binders/cobalophilins), released by proteases
-B12+Intrinsic Factor --> ileum
-B12+transcobalamin II --> plasma --> proliferating cells, marrow

11

sideroblastic anemia occurs due to defective ____ (enzyme)

ALA synthase

12

Acute Intermittent Porphyria occurs due to defective ____ (enzyme); results in accumulation of _____

porphobilongen deaminase; porphobilinogen

13

Porphyria cutanea tarda occurs due to defective ____ (enzyme); results in accumulation of ____.

It is managed by what three things? And how do these each help?

uroporphyrinogen decarboxylase; uroporphyrinogen

phlebotomy - removes iron, which oxidizes uroporphyrinogen to uroporphyrin and other things that can inhibit uroporphyrinogen decarboxylase

sunscreen - skin

chloroquine - complexes uroporphyrin to be excreted in urine

14

____ catalyzes the rate-limiting step of heme synthesis. It also requires ___ cofactor

ALA synthase; vitamin B6 (pyridoxal phosphate is active form)

15

ALA synthase is stimulated by ____ and inhibited by ____

ETOH, barbiturates; heme

16

What two enzymes in the heme synthesis pathway are inhibited by heavy metals?

ALA synthase; ferrochelatase

17

Warfarin MOA?

inhibits Vitamin K epoxide reductase, prevent Vit K recycling and thus inhibiting functional serine proteases and proteins C/S

Has initial procoagulant effect since it the anticoagulant proteins C/S are affected first due to their short half lives --> hypercoagulability and skin necrosis

18

Heparin MOA?

binds antithrombin to make it more active in

indicated for short term prophylaxis and treatment of venous thrombosis, PE, and some coagulopathies

19

Clopidogrel?

Binds platelet ADP receptors

20

How would Vitamin K deficiency affect PT and PTT?

What factors does Vit K affect?

PT increased because factor VII has a short half life

PTT would be normal except for when severe Vit K deficiency

Vit K gamma carboxylates all the serine proteases (2, 7, 9, 10, 11) and proteins C/S

21

HUS

is like TTP but in the kidneys

triggered by shiga-like toxin, E.coli O157:

22

ITP

immune mediated thrombocytopenia

due to IgG autoantibodies against platelet surface glycoproteins

acute - in children often after viral infection, self-limiting
chronic - in adults

23

Direct fibrinolytics target ___?

plasminogen (activates)

24

HIT (heparin induced thrombocytopenia) occurs ____ days after heparin exposure.

Describe the etiology?

5-14 days (faster timing if exposed before in the last 90 days)

Platelet Fc receptor binds heparin-PF4 complex, causing indiscriminate platelet activation wherever these complexes are

25

Describe the etiology and diagnosis of Antiphospholipid Syndrome?

Antiodies against epitopes of plasma proteins bound to phospholipids (lupus anticoagulant, anticardiolipin antibodies, antibeta2 GP1 antibodies)

Must have positive antiphospholipid test once and again after at least 12 weeks

AND

some clinical manifestation of thrombosis

26

Thrombomodulin function

converts thrombin into an anticoagulant that can activate protein C