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Flashcards in normocytic hemolytic anemia Deck (34):
1

RBC hemolyisis → ↑ Hb in blood
↓ serum haptoglobin: binds free Hb in blood so it can be recycled, prevents breakdown to bilirubin
RBC hemolyisis → ↑ LDH in blood
↑ LDH (lactate dehydrogenase, lot in RBCs): pyruvate → lactate

intravascular hemolysis

2

↑ unconjugated bilirubin → jaundice
↑ LDH (lactate dehydrogenase, lot in RBCs): pyruvate → lactate

extravascular hemolysis

3

defect of proteins that interact with RBC membrane + cytoskeleton: ankyrin, spectrin (gives biconcave shape + flexibility) → RBC spheres
spleen recognizes + removes abnormal RBCs → splenomegaly

hereditary spherocytosis

4

↓ G6PD → ↓ glutathione → RBC sensitive to oxidative damage → hemolysis
back pain + hemoglobinuria few days after start DRUG
extravascular + intravascular hemolysis
resistant to malaria

G6PD deficiency

5

no central pallor
↑ MCHC: contain same absolute amount of Hb but smaller cell
↑ RDW

hereditary spherocytosis

6

complication of hereditary spherocytosis

aplastic crises due to parvovirus B19 infection (suppresses BM)

7

diagnostic test for hereditary spherocytosis

osmotic fragility test: put RBC in hypoosmotic solution → high % lysis of RBCs at any given concentration of NaCl (no normal spectrin)

8

treatment for hereditary spherocytosis

splenectomy: prevent removal of RBCs

9

post-splenectomy for hereditary spherocytosis

Howell Jolly Bodies: basophilic nuclear remnants in RBC (not removed by spleen)

10

Heinz bodies: oxidation of iron, denaturation of Hb
Bite cells: spleen remove Heinz bodies

G6PD deficiency

11

glycolytic enzyme deficiency → no ATP in RBC → can't maintain Na/K ATPase → RBC swelling + hemolysis

pyruvate kinase deficiency

12

RBC missing surface markers: CD55 + CD59
complement attacks → lyses RBC

paroxysmal nocturnal hemoglobinuria

13

diagnostic test for PNH

Ham's test:
add pH → activates complement → lysis of RBC
flow cytometry (used now)

14

HbS: glutamic acid → valine in ß chain at position 6
allows Hb to polymerize in RBC
triggers of sickling = sickle crisis:
hypoxemia
dehydration
acidosis
8% AA heterozygotes (HbS trait): resistant to malaria
0.2% AA homozygous

sickle cell disease

15

infant: asymptomatic (HbF)
infant + toddler: symptoms (HbF → HbS)
splenic sequestration crisis →↓ H/H, wedge-shaped infarcts on CT
autosplenectomy: complete infarction by 3-4 yo, ↑ risk infections by encapsulated organisms (vaccinate for meningococcus, pneumococcal, flu vaccine too)
aplastic crisis post-parvovirus B19
pain crises: vasoocclusion → ischemia
renal papillary necrosis due to hypoxemia in kidneys

sickle cell disease

16

osteomyelitis in sickle cell disease

salmonella

17

causes of aplastic crisis post-parvovirus B19

sickle cell disease
hereditary spherocytosis

18

types of pain crises: vasooclusion

dactylitis: painful hand swelling
acute chest syndrome

19

"hair-on-end" appearance from marrow hyperplasia (↑ RBC production)

sickle cell disease
ß thalassemias

20

treatment of sickle cell disease

hydroxyurea: ↑ production of HbF
definitive: BMT (stem cells without HbS mutation)

21

glutamic acid → lysine on ß globin chain on position 6
HbC form crystals in cell instead of long polymers in sickle cell disease
heterozygous for HbC: asymptomatic
homozygous for HbC: milder than sickle cell disease
SC disease = heterozygote with HbS + HbC mutation: milder than SCD
mild hemolysis, splenomegaly

hemoglobin C disease

22

RBC mechanically damaged as they pass through lumen of obstructed or narrowed vessel → RBC sheared by fibrin strand or shear force of HTN:
DIC
TTP/HUS
lupus
malignant HTN

microangiopathic anemia

23

shistocytes

microangiopathic anemia or macroangiopathic anemia

24

damage to RBC by prosthetic heart valve, aortic stenosis

macroangiopathic anemia

25

RBC infection → hemolysis

malaria
babesiosis

26

autoantibodies bind to RBC → hemolysis
either warm or cold agglutinins

autoimmune hemolytic anemia

27

IgG antibodies attach to RBC antigen at BODY TEMP → RBC agglutination (clump together) → chronic anemia
EBV/HIV
lupus
CLL, non-hodgkin lymphoma
congenital immune abnormalities
drugs

warm agglutinins in autoimmune hemolytic anemia

28

IgM antibodies attach to RBC antigen ONLY IN COLD→ complement fixation → MAC lysis (and opsonization → phagocytosis) → acute anemia
EBV infection
Mycoplasma infection
CLL

cold agglutinins in autoimmune hemolytic anemia

29

most autoimmune hemolytic anemias have a positive

+ coombs test: RBC agglutination with addition of anti-human antibody because RBCs are coated with Ig or complement proteins (C3)

30

prepared Abs (coombs reagant) are added to a patient's washed RBCs to detect the PRESENCE of Igs ALREADY on RBC (using antibody to detect an antibody) → RBCs agglutinate

direct coombs test

31

+ direct coombs test

hemolytic disease of newborn
drug-induced autoimmune hemolytic anemia
hemolytic transfusion reactions

32

patient's SERUM incubated with normal RBC to detect for presence of ABs in serum → if Abs bind to RBCs →
RBCs agglutinate when anti-Ig antibodies (coombs reagant) added

indirect coombs test

33

+ indirect coombs test

Abs to foreign RBCs/blood are present:
test blood prior to transfusion (type and screen: donor blood screened for Abs)
screen for maternal Abs to a fetus's blood

34

anemia
jaundice: extravascular hemolysis in spleen
pigmented gallstones: ↑ bilirubin
splenomegaly
spherocytes
+ osmotic fragility test

hereditary spherocytosis

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