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Flashcards in Hematology, oncology Deck (201):
1

Treatment for refractory ITP?

splenectomy

2

What binds GPIIB/IIIA?

*Fibrinogen

3

Weibel-palade

Granules that contain VW factor and P-selectin in endothelial cells.

4

erythrocyte structure

enucleate + lacks organelles

5

RBC life span

120 days

6

anisocytosis

RBCs of varying sizes

7

poikilocytosis

RBCs of varying shapes

8

What does bluish color on Wright-Giemsa stain of reticulocytes represent?

Residual ribosomal RNA

9

thrombocyte life span

8-10 days

10

What do platelets interact with to form platelet plugs?

fibrinogen

11

What are alpha granules?

Granules within platelets that contain vWF + fibrinogen + fibronectin.

12

What are dense granules?

Granules within platelets that contain ADP + calcium.

13

storage site for platelets?

1/3 of platelet pool is stored in the spleen.

14

Etiology of petechiae

thrombocytopenia OR decreased platelet function

15

What is the receptor for vWF?

GpIb

16

What is the fibrinogen receptor?

GpIIb/IIa

17

granulocytes?

1) neutrophils
2) eosinophils
3) basophils

18

Mononuclear cells?

1) monocytes
2) lymphocytes

19

normal neutrophil range

54-62%

20

normal lymphocyte range

25-33%

21

normal monocyte range

3-7%

22

normal eosinophil range

1-3%

23

normal basophil range

0-0.75%

24

What are contained in neutrophil granules?

1) leukocyte alkaline phosphatase (LAP)
2) collagenase
3) lysozyme
4) lactoferrin

25

What are azurophilic granules?

Lysosomes in neutrophils that contain proteinases, acid phosphatase, myeloperoxidase, and beta-glucuronidase.

26

Why do hypersegmented neutrophils indicate?

B12/folate deficiency

27

What do increased bands indicate?

States of myeloid proliferation (bacterial infections, CML)

28

Neutrophil chemotactic agents

1) C5a
2) IL-8
3) LTB4
4) kvllikrein
5) platelet-activating factor

29

What is a monocyte?

precursor to macrophage. Monocytes exist in the blood, and when they reach tissue, differentiate into macrophages.

30

Monocyte description

1) Large, kidney-shaped nucleus.
2) extensive "frosted glass" cytoplasm.

31

describe macrophage involvement in septic shock pathogenesis

Lipid A from bacterial LPS binds CD14 on macrophages to initiate septic shock.

32

eosinophil functions

1) defense against helminths
2) highly phagocytic for antigen-antibody complexes

33

eosinophil description

1) bilobate nucleus
2) large eosinophilic granules of uniform size

34

What do eosinophils produce?

1) MBP
2) *histaminase (inactivates histamine)

35

Causes of eosinophilia

NAACP
Neoplasia
Asthma
Allergic processes
Chronic adrenal insufficiency
Parasites (invasive)

36

Basophil functions

1) Mediate allergic reactions
2) Synthesize and release leukotrienes on demand.

37

What do basophilic granules contain?

1) heparin
2) histamine

38

Basophilia think...

CML

39

Mast cell function?

Mediate allergic reactions in local tissues (type 1)

40

mast cell in allergic reactions mechanism

Bind the Fc portion of IgE to membrane. IgE cross-links upon antigen binding leading to degranulation and release of histamine, heparin, tryptase, and eosinophil chemotactic factors.

41

Cromolyn sodium clinical use + mechanism

1) asthma prophylaxis
2) prevents mast cell degranulation

42

What is the link between the innate and adaptive immune systems?

Dendritic cell

43

What do dendritic cells express on their surface?

MHC class II + Fc

44

Lymphocyte?

B cell, T cell, or NK cell

45

Lymphocyte description

Round, densely staining nucleus with small amount of pale cytoplasm.

46

What is the costimulatory signal necessary for T-cell activation?

CD28

47

Plasma cell characteristics

1) "clock-face" chromatin distribution and eccentric nucleus
2) abundant RER
3) well-developed Golgi apparatus

48

Where are plasma cells usually found?

Bone marrow. Normally do not circulate in peripheral blood.

49

Fetal erythropoiesis timeframe

Young Liver Synthesizes Blood

1) Yolk sac (3-8 weeks)
2) Liver (6 weeks--birth)
3) Spleen (10-28 weeks)
4) Bone marrow (18 weeks to adult)

So in neonatal period, there's RBC production in the liver + spleen + bone marrow.

50

What are the embryonic globins

zeta and epsilon

51

fetal hemoglobin structure

2 alphas, 2 gammas

52

Clinical relevance of AB blood type

1) Universal recipient of RBCs
2) universal donor of plasma (no antibodies produced)

53

What immunoglobulin type is anti-B or anti-A?

IgM

54

Clinical relevance of O blood type

1) If they receive any non-O blood they'll get a hemolytic reaction.
2) Universal donor of RBCs (no antigens expressed on surface)
3) **universal recipient of plasma

55

Clinical relevance of Rh positive blood?

Universal recipient of RBCs

56

What immunoglobulin isotope is against Rh proteins?

IgG

57

Rhogam mechanism

Anti-D Ig immunoglobulins, which attack and hemolyze fetal RBCs in the maternal blood stream in order to prevent her from developing an immune response to Rh proteins and attacking the fetus.

58

How do you prevent anti-D IgG production?

Give RhoGAM in third trimester.

59

more common hemolytic disease of the newborn?

ABO hemolytic disease

60

Usual scenario of ABO hemolytic disease?

Type O mother with a type A,B, or AB fetus.

61

Difference between Rh hemolytic disease and ABO hemolytic disease?

1) ABO can occur in a first pregnancy because maternal anti-A or anti-B are formed early in life.
2) ABO doesn't worsen with future pregnancies.

62

ABO hemolytic disease presentation

Mild jaundice in the neonate within 24 hours of birth.

63

ABO hemolytic disease treatment

Phototherapy or exchange transfusion.

64

missense mutation in HbS?

glutamic acid --> valine

65

missense mutation in HbC?

glutamic acid --> lysine

66

hemoglobin electrophoresis mnemonic?

A Fat Santa Claus
A migrates the farthest, followed by fetal hemoglobin, HbS, and HbC. See FA 383

67

bradykinin affects

1) vasodilation
2) increased permeability
3) increased pain

68

direct thrombin inhibitors

argatrobran
bivalirudin
dabigatran

69

thrombolytics

alteplase
reteplase
*streptokinase
tenecteplase

70

kallikrein mechanism

HMWK --> bradykinin

71

Tissue factor function

VII --> VIIa

72

What steps in the coagulation cascade require Ca, phospholipid?

1) VII --> VIIa
2) VIIa --> X
3) VIIa
4) Va

73

Epoxide reductase?

Enzyme that reduces vitamin K, allowing it to act as a cofactor

74

Gamma-glutamyl transferase function?

Uses vitamin K to activate vitamin-k dependent components of coagulation cascade.

75

Vitamin K dependent components?

II,VII,IX,X,C and S

76

Warfarin mechanism

Inhibits epoxide reductase

77

vWF function?

Carries and protects factor VIII

78

Protein C and S mechanism

Thrombin-thrombomodulin complex on endothelial cells activates protein C. Activated protein C and protein S cleave and inactivate Va, VIIIa.

79

tPA mechanism

Activates plasminogen to plasmin

80

Plasmin function?

fibrinolysis:
1. cleavage of fibrin mesh
2. destruction of coagulation factors

81

Antithrombin mechanism

Inhibits activated forms of factors II, VII, IX, X, XI, and XII.

82

heparin mechanism

Enhances activity of antithrombin.

83

Principal targets of antithrombin

Thrombin + factor Xa

84

Factor V leiden mechanism

Produces a factor V resistant to inhibition by activated protein C

85

Weibel-palade bodies?

Granules in endothelial cells that contain vWF

86

Primary hemostasis

platelet plug formation

87

platelet plug formation mechanism

1) injury
2) exposure
3) adhesion
4) activation
5) aggregation

88

describe injury step of primary hemostasis

Endothelial damage --> transient vasoconstriction via neural stimulation reflex and endothelin (released from damaged cell)

89

describe exposure step of primary hemostasis

vWF binds to exposed collagen

90

describe adhesion step of primary hemostasis

Platelets bind vWF via GpIb receptor at the site of injury --> platelets undergo conformation change --> platelets release ADP and Ca2+ (necessary for coagulation cascade) and thromboxane --> ADP helps platelets adhere to endothelium.

91

ADP function in primary hemostasis?

1) Helps platelets adhere to endothelium.
2) binding to receptor induces GpIIb/IIIa expression at platelet surface

92

describe activation step of primary hemostasis

ADP binding to receptor induces GpIIb/IIIa expression at platelet surface.

93

describe aggregation step of primary hemostasis

Fibrinogen binds GpIIb/IIIa receptors and links platelets. Balance between pro-aggregation and anti-aggregation factors. Temporary plug stops bleeding but it's unstable and easily dislodged. Secondary hemostasis occurs afterward with the coagulation cascade.

94

Anti platelet aggregation factors?

1) PGI2 and NO (released by endothelial cells)
2) Increased blood flow

95

pro aggregation factors

1) TXA2
2) *decreased blood flow
3) increased platelet aggregation

96

source of thromboxane?

Platelets

97

what is thrombogenesis?

Formation of insoluble fibrin mesh.

98

GpIIB/IIIa inhibitors?

Abciximab
Eptifibatide
Tirofiban

99

Ristocetin mechanism?

Activates vWF to bind GpIb.

100

Failure of agglutination assay with ristocetin indicates..

1) vWF disease
OR
2) Bernard-Soulier syndrome

101

Thromboplastin

Plasma protein that aids in blood coagulation through catalyzing conversion of prothrombin to thrombin.

102

What are acanthocytes associated with?

1) liver disease
2) abetaliproteinemia (states of cholesterol dysregulation)

103

Abetalipoproteinemia

♣ Code: baby looking like kevo on the ground with a distended abdomen + shitting really nasty-smelling poop/manifests during first year of life with symptoms of malabsorption (abdominal distention + foul-smelling stool). /inherited inability to synthesize apolipoprotein B, an important component of chylomicrons and VLDLs. Fern like structures sticking out of the walls everywhere clear fatty deposits in them/lipids absorbed by the small intestine cannot be transported into the blood and accumulate in the intestinal epithelium, resulting in enterocytes with clear or foamy cytoplasm. Tyrion in the bunk bed + /autosomal recessive loss-of-function mutation in the MTP gene. Baby is swing a medieval ball and chain/acanthocytes. Bunk to right is a yellow taxi + eye on the window looking like below/other presentation = progressive ataxia + retinitis pigmentosa (progressive degeneration of rod photoreceptors.
♣ Location: Bunkroom

104

What is associated with basophilic stippling?

1) lead poisoning
2) sideroblastic anemias
3) myelodysplastic syndromes

105

dacrocyte?

teardrop cell

106

degmacye?

bite cell

107

Burr cell?

echinocyte

108

Where are echinocytes found?

1) ESRD
2) liver disease
3) pyruvate kinase deficiency

109

Differentiating echinocytes from acanthocytes?

Echinocyte projections are more uniform and smaller.

110

Hereditary elliptocytosis
1) blood smear
2) presentation
3) genetics

1) elliptocytes
2) usually asymptomatic
3) mutation in genes encoding RBC membrane proteins (eg spectrin)

111

Macro-ovalocytes seen in..

1) megaloblastic anemia
2) marrow failure

112

Schistocytes seen in...

1) DIC
2) TTP/HUS
3) HELLP syndrome
4) mechanical hemolysis (heart valve prosthesis)

113

helmet cell

type of schistocyte

114

When does sickling occur?

1) dehydration
2) deoxygenation
3) high altitude

115

When are spherocytes seen?

1) hereditary spherocytosis
2) drug and infection-induced hemolytic anemia.

116

When are target cells seen?

HALT said the hunter to his target.
HbC disease
Asplenia
Liver disease
Thalassemia

117

Etiology of Heinz bodies

Oxidation of Hb -SH groups to -S--S- --> Hb precipitation

118

When are Howell-Jolly bodies seen?

1) functional hyposplenia
2) asplenia

119

What are Howell-Jolly bodies?

Basophilic nuclear remnants. Remnants of the nucleus. They are normally removed from RBCs by splenic macrophages.

120

Other anemia that can by microcytic...

Late stage of ACD

121

Distinguishing an H pylori duodenal ulcer from ZES ulcer?

H pylori is in first part of duodenum. ZES ulcers generally more distal.

122

approach to anemia problems?

1) look at MCV
2) look at reticulocyte count

123

What does reticulocyte count tell you?

If it's normal or decreased it's a non hemolytic anemia. If increased, it's a hemolytic anemia.

124

Normocytic anemias with decreased reticulocyte count...

1) *early IDA
2) early ACD
3) aplastic anemia
4) CKD

125

anemia related to copper deficiency...

Microcytic sideroblastic anemia

126

Megaloblastic macrocytic anemias

1) folate deficiency
2) B12 deficiency
3) *orotic aciduria

127

non-megaloblastic macrocytic anemia

1) liver disease
2) alcoholism
3) Diamond-Blackfan anemia

128

Approach to macrocytic anemias...

Determine if megaloblastic or non-megaloblastic

129

How to determine MCV on blood smear

Lymphocyte nucleus is roughly the same size as a normocytic RBC. If RBC is larger than lymphocyte nucleus, consider macrocytosis. If smaller --> microcytosis.

130

When do you get iron deficient

1) chronic bleeding
2) malnutrition
3) absorption disorders
4) pregnancy (increases demand in final step in heme synthesis)

131

labs in IDA

Decreased iron
Increased TIBC
Decreased ferritin

132

When do RBCs look like in IDA?

small and area of central pallor (hypochromasia)

133

What does pica indicate?

Iron deficiency anemia

134

krukenberg related to..

diffuse GI cancer

135

Sister mary joseph related to..

intestinal GI cancer

136

spoon nails medical term..

koilonychia

137

other RF for intestinal GI cancer

type A blood

138

What is Hb Barts?

Excess gamma-globing formation (all subunits gamma) from 4 allele deletion.

139

What is HbH disease?

3 alelle deletion: inheritance of chromosome with cis deletion + a chromosome with 1 allele deletion.

140

Components of HbH

Very little alpha-globin. Excess Beta-lgobin forms (4 betas)

141

What happens with 2 alpha alleles deleted?

Less clinically severe anemia.

142

What happens with 1 alpha allele deleted?

No anemia (clinically silent)

143

Genetics of beta-thalassemia?

Point mutations in splice sites and promoter sequences.

144

beta-thalassemia minor presentation?

Usually asymptomatic.

145

B-thalassemia diagnosis?

HbA2 greater than 3.5 on electrophoresis.

146

B-thalassemia major presentation

severe anemia. These people need blood transfusion.

147

Major cause of secondary hemochromatosis?

Beta-thalassemia major

148

Beta-thalassemia features

1) "crew cut" on skull x-ray
2) skeletal deformities
3) "chipmunk" facies
4) hepatosplenomegaly (due to extramedullary hematopoiesis

149

What are beta thalassemia major patients at increased risk for?

parvovirus B19-induced aplastic crisis.

150

Hemoglobin in beta-thalassemia major components?

Increased fetal hemoglobin. (a2gamma2)

151

Presentation of HbS/beta-thalassemia heterozygote?

Mild to moderate sickle cell disease depending on amount of beta-globin production.

152

Lead poisoning etiology and effect

lead inhibits ferrochelatase and ALA dehydratase, leading to decreased heme synthesis and increased RBC protoporphyrin.

153

What else does lead inhibit?

rRNA degradation. This is why you get rRNA aggregates (basophilic stippling)

154

Lead poisoning Presentation

LEAD
Lead lines on gingival and on metaphases of logan bones.
Encephalopathy and Erythrocyte basophilic stippling.
Abdominal colic and sideroblastic Anemia
Drops-- wrist and foot drop

155

sideroblastic anemia inheritance

X-linked defect

156

sideroblastic anemia etiology

defect in delta-ALA synthase gene

157

Causes of sideroblastic anemia...

1) genetic
2) myelodysplastic syndromes
3) alcohol
4) lead
5) B6 deficiency
6) copper deficiency
7) isoniazid

158

treatment for sideroblastic anemia

pyridoxine (B6, which is a cofactor for delta-ALA synthase)

159

Labs in sideroblastic anemia

1) Increased iron
2) normal to decreased TIBC
3) increased ferritin

160

blood smear finding in sideroblastic anemia

basophilic stippling of RBCs

161

what causes megaloblastic anemia?

Impaired DNA synthesis, so nucleus maturation is delayed relative to cytoplasm.

162

physical exam finding in megaloblastic anemia...

Glossitis (inflammation, soreness of the tongue)

163

What else can cause folate deficiency?

1) hemolytic anemia
2) pregnancy

164

How do you differentiate folate from b12 deficiency.

*no neurologic symptoms with folate deficiency.

165

labs in B12 deficiency

Increased homocysteine + increased methylmalonic acid

166

Why do you subacute combined degeneration in b12 deficiency?

B12 is involved in fatty acid pathways and myelin synthesis.

167

What is subacute combined degeneration?

spinocerebellar tract + lateral corticospinal tract + dorsal column dysfunction.

168

Orotic acuduria etiology

Inability to convert orotic acid to UMP (de novo pyrimidine synthesis pathway) because of defect in UMP synthase.

169

orotic acuduria inheritance

autosomal recessive.

170

Megaloblastic anemia refractory to folate and B12 think...

orotic aciduria

171

treatment for orotic acuduria?

uridine monophosphate to bypass mutated enzyme.

172

How do you differentiate orotic aciduria from ornithine transcarbamylase deficiency?

No hyperammonemia in orotic aciduria.

173

Physical exam finding in orotic aciduria?

Orotic acid in urine

174

Diamond-Blackfan anemia

Rapid-onset anemia within 1st year of life due to intrinsic defect in erythroid progenitor cells.

175

Diamond-Blackfan anemia

Increased HbF but decreased total Hb.

176

Diamond-Blackfan anemia presentation?

Short stature + craniofacial abnormalities + upper extremity malformations (triphalangeal thumbs).

177

Nonmegaloblastic anemia

Microcytic anemia in which DNA synthesis is unimpaired.

178

Nonmegaloblastic anemia on smear

RBC macrocytosis without hypersegmented neutrophils

179

If there are no hypersegmented neutrophils and macrocytic?

1) alcoholism
2) liver disease

180

Where would you block the brachial plexus?

Between anterior and middle scalenes.

181

Findings in intravascular hemolysis

1) decreased haptoglobin
2) Increased LDH
3) schistocytes and increased reticulocytes on blood smear

182

urine findings with intravascular hemolysis

1) hemoglobinuria
2) hemosiderinuria
3) urobilinogen
4) possibly increased unconjugated bilirubin

183

What is extravascular hemolysis?

Macrophages in spleen clearing RBCs

184

Findings in extravascular hemolysis

1) spherocytes in peripheral smear
2) Increased LDH.
3)***no hemoglobinuria/hemosiderinuria
4) increased unconjugated bilirubin.

185

urine findings with extravascular hemolysis

1) urobilinogen

186

ACD associations

1) RA
2) SLE
3) neoplasia
4) CKD

187

ACD findings

1) decreased iron
2) decreased TIBC
3) increased ferritin

188

treatment for ACD related to CKD?

EPO

189

ACD classification

Normocytic, but can become microcytic

190

Underlying etiology of aplastic anemia

destruction of myeloid stem cells

191

Drugs that can cause aplastic anemia?

1) benzene
2) chloramphenicol
3) alkylating agents
4) antimetabolites

192

viruses that can cause aplastic anemia?

1) parvovirus B19
2) EBV
3) HIV
4) hepatitis

193

falcon anemia

short stature + increased incidence of tumors/leukemia + cafe-au-lait spots + thumb/radial defects.

194

Other common cause of aplastic anemia

Following acute hepatitis

195

Labs in aplastic anemia?

1) decreased reticulocyte count
2) increased EPO

196

dry bone marrow tap...

aplastic anemia

197

symptoms of aplastic anemia..

Fatigue + malaise + pallor + purpura + mucosal bleeding + petechiae + infection.

198

Aplastic anemia treatment

1) stop the drug.
2) immunosuppression with antitymocyte globulin Or cyclosporine
3) bone marrow allograft
4) RBC/platelet transfusion
5) bone marrow stimulation (eg, GM-CSF)

199

defective proteins in hereditary spherocytosis

1) nnkyrin
2) band 3
3) protein 4.2
4) spectrin

200

hemolysis type in hereditary spherocytosis?

extravascular. Spleen is removing RBCs

201

What accumulates with lead poisoning?

protoporphyrin