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Flashcards in Hematology Deck (146)
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1
Q

Erythropoietin

A

synthesized in peritubular capillaries

2
Q

Reticulocyte count

A

measure of effective erythropoiesis; correct for degree of anemia

3
Q

Extramedullary hematopoiesis

A

Hematopoiessi outside bone marrow (e.g. spleen)

4
Q

Newborn physiologic anemia

A

drop in Hb due to replacement of HbF RBCs with HbA

5
Q

Pregnancy

A

Hb and Hct decreased

greater increase in plasma volume than RBC mass

6
Q

Anemia

A

normal oxygen saturation and arterial PO2

7
Q

MCV

A

average VOLUME of RBCs; useful for anemia classification

8
Q

MCHC

A

average Hb concentration in RBCs

9
Q

When is MCHC decreased? When is MCHC increased?

A

MCHC

  • decreased in microcytic anemias
  • increased in spherocytosis
10
Q

Thalassemias

A
  • decreased in MCV

- increased in RBC count

11
Q

RDW

A

RBC size variation

  • increased in iron deficiency
  • decreased in anemia of chronic disease, sideroblastic anemia
12
Q

Mature RBC

A

anaerobic glycolysis; no mitochondria or HLA antigens

13
Q

Total iron binding capacity is increased

A
  • in iron deficiency
14
Q

Total binding capacity is DECREASED

A

in anemia of chronic disease OR sideroblastic anemia

15
Q

% Saturation

A
  • decreased in iron deficiency or anemia of chronic disease
16
Q

% Saturation is increased

A

sideroblastic anemia

17
Q

Serum ferritin is decreased

A
  • iron deficiency
18
Q

Serum ferritin is INCREASED

A

anemia of chronic disease, sideroblastic anemia, normal thalassemia

19
Q

Microcytic anemia

A
  • seen in iron deficiency (most common cause)
  • anemic chronic disease
  • thalassemia
  • sideroblastic anemia
20
Q

Most common cause of iron defieicny in a child

A

Meckel’s diverticulum

21
Q

Iron deficiency in women < 50

A

Menorrhagia (heavy bleeding during menses)

22
Q

Iron deficiency man < 50

A

Most common cause is peptic ulcer disease

23
Q

Iron deficiency in men/women > 50

A

Colon cancer

24
Q

Stages of iron deficiency

A
  • decreased ferritin, Fe, and % saturation

- increased TIBC, normocytic then microcytic anemia

25
Q

Anemia of chronic disease

A

Most common anemia in malignancy and alcoholics

26
Q

Alpha Thalassemia trait

A

Autosomal recessive
two alpha globin gene deletions
- normal Hb electrophoresis

27
Q

HbH disease

A
  • three alpha-globin gene deletions;
  • hemolytic anemia
  • four Beta-globin genes
28
Q

Hb Bart’s disease

A

four alpha globin gene deetions

four gamma globin genes

29
Q

B- thalassemia minor

A

Autosomal Recessive

  • DNA splicing defect
  • increased HbA2 and F
  • idecreased HbA
30
Q

B-thalassemia major

A

nonsense mutation with stop codon

  • hemolytic anemia
  • very elevated HbF
  • increased HbA2
31
Q

Sideroblastic anemia

A
  • defect in mitochondrial heme synthesis producing ringed sideroblasts
32
Q

Causes of sideroblastic anemia

A
  • Alcohol
  • Pyroxidine deficiency (may be due to isoniazid tx of TB)
  • Lead poisoning
33
Q

Lead poisoning

A
  • Inhibits ferrochetolase
  • ALA Dehydrase (can’t convert ALA to porphobillogen??)
  • Ribonuclease
34
Q

Sx of lead poisoning in children

A
  • Growth retardation
  • Pb in epiphyses
  • Abdominal colic
  • Encephalopathy
35
Q

Sx of lead poisoning in adult

A

Peripheral neuropathy

Proximal renal tubule damage (Fanconi’s syndrome)

36
Q

Lab of Pb poisoning

A
  • Course basophillic stippling RBCs
  • decreased MCV
  • increase in Pb levels
  • increase in ALA
37
Q

Vitamin B12 sources

A

Animal products (requires intrinsic factor reabsorption in terminal ileum)

38
Q

Vitamin B12

A

transfers methyl group to homocysteine

  • involved in proprionate metabolism
  • end product of succinyl CoA
39
Q

R factor

A

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

40
Q

Pernicious anemia

A

autoimmune destruction of parietal cells

sx: chronic gastritis in body/fundus, acholrydia
- increase in gastrin

41
Q

Causes of folate deficiency

A
  • Alcohol (most common cause)
  • Poor diet
  • Drugs
  • Malabsorption
  • Pregnancy
  • Goat milk
42
Q

Drugs and Folate deficiency

A
  • Alcohol
  • Oral contraceptives
  • Phenytoin
  • Methrotrexate
  • Trimethroprim
  • 5-fluorouracil
43
Q

Intestinal conjugase in folate metabolism

A

Inhibited by phenytoin

44
Q

Jejunal uptake of monoglutamate of folate

A

Inhibited by alcohol and oral contraceptives

45
Q

Dihydrofolate reductase

A

inhibited by methotrexate, trimethoprim

46
Q

Thimydilate synthase

A

inhibited by 5-fluorouracil

47
Q

Most common cause of increased serum homocysteine

A

Folate deficiency

48
Q

Lab in B12/folate deficiency

A
  • Pancytopenia
  • Hypersegmented neutrophils
  • Increased in homocysteine
49
Q

Lab finds unique to B12 deficiency

A
  • increased gastrin (pernicious anemia)

- increased methylmalonic acid

50
Q

Likely diagnosis: B12 reabsorbed after administration of intrinsic factor.

A

Pernicious anemia

51
Q

Likely diagnosis: B12 reabsorbed after administration of antiobiotics

A

Bacterial overgrowth

52
Q

Likely diagnosis?

B12 reabsorbed after administration of pancreatic enzyme

A

Chronic pancreatitis

53
Q

Hb and Hct after acute blood loss

A
  • Initially normal Hb and Hct

.9% saline uncovers RBC deficit

54
Q

Aplastic anemia

A
  • Drugs (e.g. phenylbutazone)
  • Infection (e.g. parvovirus)
  • Benzene
55
Q

Lab findings for aplastic anemia

A
  • Pancytopenia
  • ## Hypocellular bone marrow
56
Q

Anemia in renal disease

A

Normocytic

- decreased EPO

57
Q

Extravascular hemolysis

A
  • Macrophage phagocytosis of RBCs

- Increase in unconjugated bilirubin and urine UBG

58
Q

Intravascular hemolysis

A
  • Decrease in serum haptoglobin
  • Hemoglobinuria
  • Hemosideriuria
59
Q

Congenital spherocytosis

A
  • Autosomal dominant
  • defectin spectrin
  • Extravascular hemolysis
  • Splenomegaly
60
Q

Blood findings in spherocytosis

A

Normocytic anemia

  • Dense RBCs
  • Increase in MCHC
  • INcrease in osmotic fragility
61
Q

Blood findings in spherocytosis

A

Normocytic anemia
dense RBCs
Increase in MCHC
Increase in osmotic fragility

62
Q

PNH

A

missing decay acceerating factor

  • complement destruction RBCs
  • neutrophils
  • platelets
63
Q

Sx of PNH

A
  • Pancytopenia
  • Hemoglobiuria
  • Positive sugar water test and acidified serum test
64
Q

HbSS

A
  • Autosomal Recessive

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

65
Q

Causes of sickling

A
  • Increase in deoxyhemoglobin (hypoxemia and acidosis)

- HbS > 60%

66
Q

HbF

A

inhibits sickling

hydroxyurea increases HbF

67
Q

Pathophysiology of HbSS

A
Vasoclusive crisises
Hemolytic anemia ( Extravascular)
68
Q

HbSS in children

A

Dactylitis (6 - 9 months)

Streptococcus pneumoniae sepsis (dysfunctional spleen)

69
Q

HbSS osteomyelitis caused by what microorganism?

A

Salmonella paratyphi

70
Q

HbSS complications

A
Aplastic crisis (parvovirus)
Acute chest syndrome
Autosplenectomy
Calciym bilirubinate gallstones
Priapism
Asceptic necrosis
71
Q

HbAS

A
  • microhematuria from sickling in renal medulla

- renal papillary necrosis

72
Q

Hb electrophoresis

A

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

73
Q

Blood findings in HbSS

A

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

74
Q

G6PD deficiency

A
X-linked recessive
Oxidant damage (due to peroxide) to Hb (e.g. primaquine, dapsone, fava beans)
75
Q

Blood findings G6PD deficiency

A
Heinz bodies (denatured Hb; special stain)
Bite cells
76
Q

Pyruvate kinase deficiency

A
  • Decreased ATP
  • RBCs dehydrated
  • increase in 2,3 BPG (right shift of oxygen-blood curve)
77
Q

Warm Autoimmune-hemolytic anemia

A
IgG
Extravascular hemolysis (e.g. SLE, drugs)
78
Q

Cold auto-immune hemolytic anemia

A
IgM 
Intravascular hemolysis (e.g. CLL, mycoplasma)
79
Q

Pencillin HS rxn

A

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

80
Q

Methyldopa

A

drug alters Rh antigens;

IgG antibody against Rh antigens (type II antibody)

81
Q

Quinidine

A

drug IgM immune complexes
intravascular hemolysis
type III hypersensitivity

82
Q

Lab findings for autoimmune hemolytic anemia

A

Positive direct Coombs

spherocytes

83
Q

Microangiopathic hemolysis

A

Mechanical damage causing intravascular hemolysis

84
Q

Causes of macro/micro hemolysis

A

Aortic stenosis (most common cause0
DIC
TTP
HUS

85
Q

Peripheral blood findings micro/macro hemolysis

A

Schistocytes

Iron deficiency from hemoglobinuria

86
Q

Malaria

A

Intravascular hemolysis correlates with fever

Falciparum - ring forms and gametocytes

87
Q

Leukemoid reaction

A

exaggerated WBC response to infection

Usually due to infection

88
Q

Leukoerythroblastic reaction

A

Marrow infiltrative disease peripheralizes myeloblasts/nucleated RBCs

89
Q

Leukemoid reaction

A

exaggerated WBC response to infection; usually due to infection

90
Q

Causes of leukoerythroblastic reaction

A

Bone metastais MCC

myelofibrosis

91
Q

Eosinophilia

A

Type I hypersensitivity (e.g. penicillin reaction)

Invasive helminthic infection

92
Q

Helminths not producing eosinophili

A

Pinworms

Adult worms in ascariasis

93
Q

Atypical lymphocytes

A
Mononucleosis
CMV
Toxoplasmosis
Viral hepatitis
Phenytoin
94
Q

Mononucleosis

A

due to EBV

EBV attaches to CD21 receptors in B cells

95
Q

Clinical findings for mononucleosis

A

Exudative tonsillitis
Generalized lymphadenopathy
Hepatosplenomegaly

96
Q

Lab findings for mononucleosis

A

Atypical lymphocytosis

IgM heterophile antibodies against horse RBCs (MONOSPOT)

97
Q

Lymphopenia

A

T-cell deficiences (HIV)

combined B/T deficiency (adenine deficiency)

98
Q

Lymphocytosis

A

Viral infections; whooping cough

99
Q

Chronic myeloproliferative disease

A

Neoplastic stem cell disorder
Splenomegaly
Marrow fibrosis
Risk of leukemia

100
Q

Examples of myeloproliferative disease

A

Polycythemia vera
Myelofibrosis
Myeloid metaplasia

101
Q

Relative polycythemia

A

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

102
Q

Absolute polycythemia

A

Increase RBC count and RBC mass

103
Q

Appropriate polycythemia

A

Hypoxic stimulus for EPO to generate RBCs

104
Q

Causes of appropriate absolute polycythemia

A

Lung disease
Cyanotic heart disease
High altitude

105
Q

Appropriate absolute polycythemia

A

Normal plasma volume
Increase in RBC mass
Decrease SaO2
Increase EPO

106
Q

Inappropriate absolute polycythemia

A

No hypoxic stimulus for EPO

107
Q

Causes of inappropriate polycythemia

A

Ectopic secretion EPO

Polycythemia vera

108
Q

Polycythemia vera

A

Increase plasma volume and RBC mass
normal SaO2
Decreased EPO

109
Q

Ectopic EPO (renal cell carcinoma)

A

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

110
Q

Myelofibrosis myeloid metaplasia

A

Marrow fibrosis
Extramedullar hematopoiesis
Splenomegaly

111
Q

Lab findings in myelofibrosis

A

Tear drop RBCs

Dry bone marrow aspirate (marrow fibrosis)

112
Q

Essential thrombocythemia

A

MPD with increase in abnormal appearing platelets

113
Q

Myelodysplastic syndrome

A

severe anemia in elderly; 30% develop leukemia

ringed sideroblasts

114
Q

Benzene

A

associated w/ aplastic anemia

acute leukemia

115
Q

Leukemia by age

A

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

116
Q

Acute vs chronic leukemia

A

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

117
Q

Acute Myeloproliferative Leukemia

A

Auer rods in myeloblasts

118
Q

Acute Promyelocytic leukemia

A

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

119
Q

Acute monocytic leukemia (AML)

A

Gum infiltration

120
Q

Chronic Myelogenous Leukemia

A

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

121
Q

ALL

A

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

122
Q

Indicators of good prognosis of ALL

A

t(12; 21)`

123
Q

Chronic Lymphoblatic Leukemia (CLL)

A

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

124
Q

Adult T-cell Leukemia

A

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

125
Q

Hairy cell leukemia

A

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

126
Q

Nodal sites

A
germinal follicles
B cells 
paracortex
T cells 
sinuses
histiocytes
127
Q

Testicular cancer metastasis

A

to para-aortic lymph nodes

128
Q

Stomach cancer metastasis

A

to supraclavicular lymph nodes

129
Q

Phenytoin side effect

A
  • ginigival hyperplasia
  • atypical lymphocytosis
  • nystagmus
  • ataxia
130
Q

Cat scratch disease

A

Bartonella henselaw

granulomatous microabscesses

131
Q

Follicular B-cell lymphoma

A

t(14, 18)

overexpression of BCL-2 (anti-apoptosis gene)

132
Q

Burkitt lymphoma

A
t(8, 14)
overexpression of c-myc
EBV association
common childhood Non-Hodgkin's Lymphoma
"starry sky appearance
133
Q

Extranodal lymphomas

A

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

134
Q

Mycosis fungiodes

A

CD4 T neoplasm
skin lesions with Pautrier’s microabcesses

  • when spread to blood becomes Sezary syndrome
135
Q

Sezary syndrome

A

leukemic phase of Mycosis fungiodes

136
Q

Polyclonal gammopathy

A

sign of chronic inflammation

137
Q

Monoclonal gammopathy

A
M component (spike)
sign of plasma cell disorder
138
Q

Bence Jones proteins

A

light chains in urine

- predicive of a malignant plasma cell disorder (e.g multiple myeloma)

139
Q

Multiple myeloma

A

patients > 45

  • M spike
  • lytic bone lesions
  • pathological fractures
  • hypercalcemia
  • renal failure
140
Q

MGUS

A

monoclonal gammopathy, may progress to myeloma

141
Q

Findings in MGUS

A

elderly patient
no Bence Jones proteins
no malignant plasma cells

142
Q

Waldenstrom’s macroglobulinemia

A

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

143
Q

Hodgkin’s lymphoma

A

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
Q

Reed Steinberg cell

A
  • seen in Hodgkin’s lymphoma
  • binucleate or bilobed halves as mirror images
  • more RS cells present the worse the prognosis
145
Q

Non-sclerosing Hodgkins

A
  • female dominant

- supraclavicular nodes + anterior mediastinal nodes

146
Q

Mixed cellularity Hodgkins

A

male dominant
numerous RS cells
EBV association