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Flashcards in Hematology Deck (146):
1

Erythropoietin

synthesized in peritubular capillaries

2

Reticulocyte count

measure of effective erythropoiesis; correct for degree of anemia

3

Extramedullary hematopoiesis

Hematopoiessi outside bone marrow (e.g. spleen)

4

Newborn physiologic anemia

drop in Hb due to replacement of HbF RBCs with HbA

5

Pregnancy

Hb and Hct decreased
greater increase in plasma volume than RBC mass

6

Anemia

normal oxygen saturation and arterial PO2

7

MCV

average VOLUME of RBCs; useful for anemia classification

8

MCHC

average Hb concentration in RBCs

9

When is MCHC decreased? When is MCHC increased?

MCHC
- decreased in microcytic anemias
- increased in spherocytosis

10

Thalassemias

- decreased in MCV
- increased in RBC count

11

RDW

RBC size variation
- increased in iron deficiency
- decreased in anemia of chronic disease, sideroblastic anemia

12

Mature RBC

anaerobic glycolysis; no mitochondria or HLA antigens

13

Total iron binding capacity is increased

- in iron deficiency

14

Total binding capacity is DECREASED

in anemia of chronic disease OR sideroblastic anemia

15

% Saturation

- decreased in iron deficiency or anemia of chronic disease

16

% Saturation is increased

sideroblastic anemia

17

Serum ferritin is decreased

- iron deficiency

18

Serum ferritin is INCREASED

anemia of chronic disease, sideroblastic anemia, normal thalassemia

19

Microcytic anemia

- seen in iron deficiency (most common cause)
- anemic chronic disease
- thalassemia
- sideroblastic anemia

20

Most common cause of iron defieicny in a child

Meckel's diverticulum

21

Iron deficiency in women < 50

Menorrhagia (heavy bleeding during menses)

22

Iron deficiency man < 50

Most common cause is peptic ulcer disease

23

Iron deficiency in men/women > 50

Colon cancer

24

Stages of iron deficiency

- decreased ferritin, Fe, and % saturation
- increased TIBC, normocytic then microcytic anemia

25

Anemia of chronic disease

Most common anemia in malignancy and alcoholics

26

Alpha Thalassemia trait

Autosomal recessive
two alpha globin gene deletions
- normal Hb electrophoresis

27

HbH disease

- three alpha-globin gene deletions;
- hemolytic anemia
- four Beta-globin genes

28

Hb Bart's disease

four alpha globin gene deetions
four gamma globin genes

29

B- thalassemia minor

Autosomal Recessive
- DNA splicing defect
- increased HbA2 and F
- idecreased HbA

30

B-thalassemia major

nonsense mutation with stop codon
- hemolytic anemia
- very elevated HbF
- increased HbA2

31

Sideroblastic anemia

- defect in mitochondrial heme synthesis producing ringed sideroblasts

32

Causes of sideroblastic anemia

- Alcohol
- Pyroxidine deficiency (may be due to isoniazid tx of TB)
- Lead poisoning

33

Lead poisoning

- Inhibits ferrochetolase
- ALA Dehydrase (can't convert ALA to porphobillogen??)
- Ribonuclease

34

Sx of lead poisoning in children

- Growth retardation
- Pb in epiphyses
- Abdominal colic
- Encephalopathy

35

Sx of lead poisoning in adult

Peripheral neuropathy
Proximal renal tubule damage (Fanconi's syndrome)

36

Lab of Pb poisoning

- Course basophillic stippling RBCs
- decreased MCV
- increase in Pb levels
- increase in ALA

37

Vitamin B12 sources

Animal products (requires intrinsic factor reabsorption in terminal ileum)

38

Vitamin B12

transfers methyl group to homocysteine
- involved in proprionate metabolism
- end product of succinyl CoA

39

R factor

binds with B12 in mouth, removed by pancreatic enymes in small intestine

40

Pernicious anemia

autoimmune destruction of parietal cells
sx: chronic gastritis in body/fundus, acholrydia
- increase in gastrin

41

Causes of folate deficiency

- Alcohol (most common cause)
- Poor diet
- Drugs
- Malabsorption
- Pregnancy
- Goat milk

42

Drugs and Folate deficiency

- Alcohol
- Oral contraceptives
- Phenytoin
- Methrotrexate
- Trimethroprim
- 5-fluorouracil

43

Intestinal conjugase in folate metabolism

Inhibited by phenytoin

44

Jejunal uptake of monoglutamate of folate

Inhibited by alcohol and oral contraceptives

45

Dihydrofolate reductase

inhibited by methotrexate, trimethoprim

46

Thimydilate synthase

inhibited by 5-fluorouracil

47

Most common cause of increased serum homocysteine

Folate deficiency

48

Lab in B12/folate deficiency

- Pancytopenia
- Hypersegmented neutrophils
- Increased in homocysteine

49

Lab finds unique to B12 deficiency

- increased gastrin (pernicious anemia)
- increased methylmalonic acid

50

Likely diagnosis: B12 reabsorbed after administration of intrinsic factor.

Pernicious anemia

51

Likely diagnosis: B12 reabsorbed after administration of antiobiotics

Bacterial overgrowth

52

Likely diagnosis?
B12 reabsorbed after administration of pancreatic enzyme

Chronic pancreatitis

53

Hb and Hct after acute blood loss

- Initially normal Hb and Hct
.9% saline uncovers RBC deficit

54

Aplastic anemia

- Drugs (e.g. phenylbutazone)
- Infection (e.g. parvovirus)
- Benzene

55

Lab findings for aplastic anemia

- Pancytopenia
- Hypocellular bone marrow
-

56

Anemia in renal disease

Normocytic
- decreased EPO

57

Extravascular hemolysis

- Macrophage phagocytosis of RBCs
- Increase in unconjugated bilirubin and urine UBG

58

Intravascular hemolysis

- Decrease in serum haptoglobin
- Hemoglobinuria
- Hemosideriuria

59

Congenital spherocytosis

- Autosomal dominant
- defectin spectrin
- Extravascular hemolysis
- Splenomegaly

60

Blood findings in spherocytosis

Normocytic anemia
- Dense RBCs
- Increase in MCHC
- INcrease in osmotic fragility

61

Blood findings in spherocytosis

Normocytic anemia
dense RBCs
Increase in MCHC
Increase in osmotic fragility

62

PNH

missing decay acceerating factor
- complement destruction RBCs
- neutrophils
- platelets

63

Sx of PNH

- Pancytopenia
- Hemoglobiuria
- Positive sugar water test and acidified serum test

64

HbSS

- Autosomal Recessive
- Missense mutation (valine for glutamic acid; 6th positive B-globin chain)

65

Causes of sickling

- Increase in deoxyhemoglobin (hypoxemia and acidosis)
- HbS > 60%

66

HbF

inhibits sickling
hydroxyurea increases HbF

67

Pathophysiology of HbSS

Vasoclusive crisises
Hemolytic anemia ( Extravascular)

68

HbSS in children

Dactylitis (6 - 9 months)
Streptococcus pneumoniae sepsis (dysfunctional spleen)

69

HbSS osteomyelitis caused by what microorganism?

Salmonella paratyphi

70

HbSS complications

Aplastic crisis (parvovirus)
Acute chest syndrome
Autosplenectomy
Calciym bilirubinate gallstones
Priapism
Asceptic necrosis

71

HbAS

- microhematuria from sickling in renal medulla
- renal papillary necrosis

72

Hb electrophoresis

HbAS - HbA (55 - 60%)
HbS (40 - 45%)
HbSS - HbS 90- 95%
HbF - 5-10%

73

Blood findings in HbSS

Sickle cells
Target cells
Howell-Jolly bodies (nuclear remnants)

74

G6PD deficiency

X-linked recessive
Oxidant damage (due to peroxide) to Hb (e.g. primaquine, dapsone, fava beans)

75

Blood findings G6PD deficiency

Heinz bodies (denatured Hb; special stain)
Bite cells

76

Pyruvate kinase deficiency

- Decreased ATP
- RBCs dehydrated
- increase in 2,3 BPG (right shift of oxygen-blood curve)

77

Warm Autoimmune-hemolytic anemia

IgG
Extravascular hemolysis (e.g. SLE, drugs)

78

Cold auto-immune hemolytic anemia

IgM
Intravascular hemolysis (e.g. CLL, mycoplasma)

79

Pencillin HS rxn

IgG antibody against penicilin attached to RBC (type II hypersenstivity)

80

Methyldopa

drug alters Rh antigens;
IgG antibody against Rh antigens (type II antibody)

81

Quinidine

drug IgM immune complexes
intravascular hemolysis
type III hypersensitivity

82

Lab findings for autoimmune hemolytic anemia

Positive direct Coombs
spherocytes

83

Microangiopathic hemolysis

Mechanical damage causing intravascular hemolysis

84

Causes of macro/micro hemolysis

Aortic stenosis (most common cause0
DIC
TTP
HUS

85

Peripheral blood findings micro/macro hemolysis

Schistocytes
Iron deficiency from hemoglobinuria

86

Malaria

Intravascular hemolysis correlates with fever
Falciparum - ring forms and gametocytes

87

Leukemoid reaction

exaggerated WBC response to infection
Usually due to infection

88

Leukoerythroblastic reaction

Marrow infiltrative disease peripheralizes myeloblasts/nucleated RBCs

89

Leukemoid reaction

exaggerated WBC response to infection; usually due to infection

90

Causes of leukoerythroblastic reaction

Bone metastais MCC
myelofibrosis

91

Eosinophilia

Type I hypersensitivity (e.g. penicillin reaction)
Invasive helminthic infection

92

Helminths not producing eosinophili

Pinworms
Adult worms in ascariasis

93

Atypical lymphocytes

Mononucleosis
CMV
Toxoplasmosis
Viral hepatitis
Phenytoin

94

Mononucleosis

due to EBV
EBV attaches to CD21 receptors in B cells

95

Clinical findings for mononucleosis

Exudative tonsillitis
Generalized lymphadenopathy
Hepatosplenomegaly

96

Lab findings for mononucleosis

Atypical lymphocytosis
IgM heterophile antibodies against horse RBCs (MONOSPOT)

97

Lymphopenia

T-cell deficiences (HIV)
combined B/T deficiency (adenine deficiency)

98

Lymphocytosis

Viral infections; whooping cough

99

Chronic myeloproliferative disease

Neoplastic stem cell disorder
Splenomegaly
Marrow fibrosis
Risk of leukemia

100

Examples of myeloproliferative disease

Polycythemia vera
Myelofibrosis
Myeloid metaplasia

101

Relative polycythemia

Decrease in plasma volume, increase in RBC count, normal RBC mass

102

Absolute polycythemia

Increase RBC count and RBC mass

103

Appropriate polycythemia

Hypoxic stimulus for EPO to generate RBCs

104

Causes of appropriate absolute polycythemia

Lung disease
Cyanotic heart disease
High altitude

105

Appropriate absolute polycythemia

Normal plasma volume
Increase in RBC mass
Decrease SaO2
Increase EPO

106

Inappropriate absolute polycythemia

No hypoxic stimulus for EPO

107

Causes of inappropriate polycythemia

Ectopic secretion EPO
Polycythemia vera

108

Polycythemia vera

Increase plasma volume and RBC mass
normal SaO2
Decreased EPO

109

Ectopic EPO (renal cell carcinoma)

Normal plasma volume
Increase in RBC mass
Normal SaO2
Increase in EPO

110

Myelofibrosis myeloid metaplasia

Marrow fibrosis
Extramedullar hematopoiesis
Splenomegaly

111

Lab findings in myelofibrosis

Tear drop RBCs
Dry bone marrow aspirate (marrow fibrosis)

112

Essential thrombocythemia

MPD with increase in abnormal appearing platelets

113

Myelodysplastic syndrome

severe anemia in elderly; 30% develop leukemia
ringed sideroblasts

114

Benzene

associated w/ aplastic anemia
acute leukemia

115

Leukemia by age

ALL: newborn
AML: 15- 60
CML: 40 - 60
CLL: > 60

116

Acute vs chronic leukemia

Acute: blasts > 30% in bone marrow
Chronic: blasts < 10% in bone marrow

117

Acute Myeloproliferative Leukemia

Auer rods in myeloblasts

118

Acute Promyelocytic leukemia

t(15; 17)
defect in retinoic acid
Rx: retinoic acid (increased maturation)
DIC

119

Acute monocytic leukemia (AML)

Gum infiltration

120

Chronic Myelogenous Leukemia

t(9; 22) of ABL proto-oncogene
Philadephia chromosome 22
Decrease leukocyte alkaline phosphatase score

121

ALL

early pre-B (80%)
CALLA (CD10)
TdT positive
CNS testicle involvement

122

Indicators of good prognosis of ALL

t(12; 21)`

123

Chronic Lymphoblatic Leukemia (CLL)

pts > 60 years
B cell neoplasm
- decrease in gamma-globulins
- Generalized lymphadenopathy

124

Adult T-cell Leukemia

HTLV-1
CD4 T-cells
skin infiltration
lytic bone lesions with hypercalcemia

125

Hairy cell leukemia

positive TRAP stain ("trap the hairy spider")
splenomegaly
Rx with purine nucleosides

126

Nodal sites

germinal follicles
B cells
paracortex
T cells
sinuses
histiocytes

127

Testicular cancer metastasis

to para-aortic lymph nodes

128

Stomach cancer metastasis

to supraclavicular lymph nodes

129

Phenytoin side effect

- ginigival hyperplasia
- atypical lymphocytosis
- nystagmus
- ataxia

130

Cat scratch disease

Bartonella henselaw
granulomatous microabscesses

131

Follicular B-cell lymphoma

t(14, 18)
overexpression of BCL-2 (anti-apoptosis gene)

132

Burkitt lymphoma

t(8, 14)
overexpression of c-myc
EBV association
common childhood Non-Hodgkin's Lymphoma
"starry sky appearance

133

Extranodal lymphomas

risk factors:
H-pylori (stomach)
Sjorgen's syndrome

134

Mycosis fungiodes

CD4 T neoplasm
skin lesions with Pautrier's microabcesses

- when spread to blood becomes Sezary syndrome

135

Sezary syndrome

leukemic phase of Mycosis fungiodes

136

Polyclonal gammopathy

sign of chronic inflammation

137

Monoclonal gammopathy

M component (spike)
sign of plasma cell disorder

138

Bence Jones proteins

light chains in urine
- predicive of a malignant plasma cell disorder (e.g multiple myeloma)

139

Multiple myeloma

patients > 45
- M spike
- lytic bone lesions
- pathological fractures
- hypercalcemia
- renal failure

140

MGUS

monoclonal gammopathy, may progress to myeloma

141

Findings in MGUS

elderly patient
no Bence Jones proteins
no malignant plasma cells

142

Waldenstrom's macroglobulinemia

lymphoplasmacytic lymphoma
IgM M spike (vs. IgG and IgA in multiple myeloma)
Hyperviscosity (b/c IgM are large molecules)

143

Hodgkin's lymphoma

neoplastic compnent Reed Stenberg cell ("owl eyes")
CD15 + and CD30+
- bimodal distribution: young adulthood or > 55 years
- EBV association
- Constitutional symptoms (e.g. weight loss, night sweats)

144

Reed Steinberg cell

- seen in Hodgkin's lymphoma
- binucleate or bilobed halves as mirror images
- more RS cells present the worse the prognosis

145

Non-sclerosing Hodgkins

- female dominant
- supraclavicular nodes + anterior mediastinal nodes

146

Mixed cellularity Hodgkins

male dominant
numerous RS cells
EBV association