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Flashcards in Red Blood Cell Disorders Deck (216):
1

Define anemia

Reduction in circulating red blood cell mass

2

What symptom does anemia present like?

Hypoxia

3

Is anemia of pregnancy actually anemia?

No, just increased plasma volume

4

Symptoms of hypoxia/anemia include? (4)

1. Weakness/fatigue/dyspnea
2. Pale conjunctiva and skin
3. Headache and lightheadedness
4. Angina

5

What measurements are used to determine RBC mass?

1. RBC count
2. Hemoglobin
3. Hematocrit

6

How is anemia defined in terms of Hb?

Males: Less than 13.5
Females: Less than 12.5

7

How is anemia defined in terms of MCV?

Microcytic: Less than 80
Normocytic: 80-100
Macrocytic >100

8

Anemias due to red cell production decrease are due to what? (2)

1. Hematopoietic cell damage
2. Deficiency of factors for heme synthesis of DNA synthesis

9

Anemias due to increased red cell loss are due to what? (2)

1. External blood loss
2. Red cell destruction

10

What is acute posthemorrhagic anemia?
What are clinical symptoms similar to

Following acute blood loss, there may be no decrease in any RBC mass markers but an increase in platelet count.

Hypovolemia

11

What are the four microcytic anemias?

1. Iron deficiency
2. Anemia of chronic disease
3. Sideroblastic anemia
4. Thalassemias

12

Microcytic anemia has what MCV?

Less than 80

13

Microcytic anemias are simply the result of what?

Decreased production of hemoglobin

14

Why does the microcytosis occur in microcytic anemias?

Extra cellular divisions to make smaller cells with same hemoglobin concentration as normal RBC's.

15

Hemoglobin is made of what?

Heme and globin

16

Heme is made of what?

Iron and protoporphyrin

17

A decrease in what substances will result in a microcytic anemia? (3)

1. Globin
2. Iron
3. Protoporphyrin

18

What is the most common type of anemia?
Why?

Iron-deficiency anemia
Most common nutritional deficiency in the world.

19

Absorption of iron occurs where?

Duodenum

20

What are the two forms iron is absorbed in?
Which is absorbed more readily?
What are the transporters for each

1. Heme form (from meat): Absorbed quicker
2. Non heme form (from vegetables)

1. Heme: Heme transporter
2. Non-heme: DMT-1

21

What is the key regulatory step of iron absorption?

Will iron be transferred from enterocyte into the blood via ferroportin

22

What is the function of transferrin?

Transports iron in the blood and delivers it to the liver and bone macrophages for storage.

23

Stored intracellular iron is bound by what?
Purpose of this?

Ferritin

Prevent free radical formation

24

What is serum iron?

Measurement of iron in the blood

25

What is TIBC?

Total-iron binding capacity which is a measure of transferrin in blood

26

What is % saturation?
What is normal

Percentage of transferrin molecules that are bound by iron

33%

27

What is serum ferritin?

Measure of iron stored in macrophages and liver

28

Iron deficiency is usually caused by what two paths?

1. Dietary lack of iron
2. Blood loss

29

Most common causes of blood loss leading lack of iron? 3

1. Menorrhagia
2. Peptic ulcer disease in males
3. Bleeding GI lesions

30

What two types of GI lesions are seen causing iron deficiency?
What population demographic specifically?

1. Colon polyps/carcinoma in the Western world
2. Hookworms in developing world

Elderly

31

What populations see menorrhagia and peptic ulcer disease?

1. Menorrhagia: Females between 20 and 50
2. Peptic ulcer: Males between 20 and 50

32

Dietary deficiency is seen in what 3 manifestations?

1. Infants: Human milk has very low iron
2. Children: Poor diet or grow quickly
3. Pregnant mothers: Need more iron for baby and herself

33

What effect does gastrectomy have on iron absorption?

Stomach acid normally maintains iron in Fe2+ state which absorbs fast. Without stomach acid, iron is in Fe3+ state in GI tract.

34

What are the four stages of iron deficiency?

1. Storage iron depleted: Low ferritin and high TIBC
2. Serum iron depleted: Low serum iron & percent saturated
3. Normocytic anemia: Make fewer normal RBC's
4. Microcytic anemia: Make smaller and fewer RBC's

35

What are the clinical features of iron deficiency? 6

1. Anemia
2. Koilonychia
3. Pica
4. Pallor
5. Fatigue
6. Dyspnea on exertion

36

What is Plummer Vinson syndrome? 3
How does it present?

1. Severe iron deficiency anemia
2. Atrophic glossitis
3. Esophageal web

1. Anemia
2. Dysphagia
3. Beefy-red tongue

37

Lab findings of Iron-deficiency anemia?
1. Appearance of RBC's
2. RDW
3. Ferritin
4. TIBC
5. Serum Iron
6. Percent saturated
7. Free erythrocyte protoporphyrin (FEP)
8. Hb
9. Hematocrit
10. RBC count

1. Small hypochromic RBC's
2. Increased (some normo and some micro)
3. Decreased
4. Increased
5. Decreased
6. Decreased
7. Increased
8. Decreased
9. Decreased
10. Decreased

38

What is most sensitive diagnostic of iron-deficient anemia?
What is one negative?

Serum ferritin

Serum ferritin elevates in pro-inflammatory states

39

Where is iron in terms of chronology of heme synthesis?

Last step

40

How to differ between Iron-deficiency and anemia of chronic disease?

Anemia of chronic disease has a low TIBC compared to ID-A.

41

How to differ between Beta-thalassemia minor and ID-A?

Increased Hb A2 in Beta-thalaseemia minor

42

Treatment of ID-A?

Supplemental iron (Ferrous sulfate)

43

Anemia of chronic disease is secondary to what types of diseases? 2

1. Chronic inflammation (arthritis, infection)
2. Cancer

44

Anemia of chronic disease is most common in what population of patients?

Hospitalized patients

45

Chronic inflammation results in production of what?
Specifically?

Production of acute-phase reactants

Hepcidin

46

What is the function of hepcidin?

Hepcidin sequesters iron in storage sites by limiting iron transfer from macrophages to erythroid precursors AND suppressing EPO production.

47

How does A-CD appear at first?
Then what does it become?

1. Normochromic and normocytic
2. Hypochromic and microcytic

48

What are the lab findings in A-CD?
1. Ferritin
2. TIBC
3. Serum iron
4. % saturation
5. FEP

1. Increased
2. Decreased
3. Decreased serum iron
4. Decreased
5. Increased

49

Treatment of A-CD? (2)

1. EPO for cancer patients
2. Auto-immune disease treatment for chronic inflammed patients

50

Sideroblastic anemia is due to what?

Defective protoporphyrin synthesis

51

What is the first reaction in heme synthesis?
What is the co-factor?

Aminolevulinic acid synthetase (ALAS) converts succinyl CoA to aminolevulinic acid (ALA)

Vitamin B12

52

What is the second reaction of heme synthesis?

Aminolevulinic acid dehydratase (ALAD) converts ALA to porphobilinogen

53

What is the final reaction of heme synthesis?
Where is this located?

Ferrochelatase attaches protoporphyrin to iron to make heme

Mitochondria

54

What is the rate limiting step of heme synthesis?

First reaction to make ALA

55

If proto-porphyrin is deficient what happens to iron?
How does this appear?

Remains trapped in mitochondria

These iron-laden mitochondria form a ring around nucleus in erythroid precursors that are called ringed sideroblasts

56

What is the congenital cause of sideroblastic anemia?

X-linked defect in ALAS enzyme

57

What are the three acquired causes of sideroblastic anemia?
Explain each

1. Alcoholism: Mitochondrial poison
2. Lead poisoning (Inhibits ALAD and ferrochelatase)
3. B6 deficiency: Required cofactor for ALAS and is decreased when treated with isoniazid

58

Lab findings in sideroblastic anemia?
1. Ferritin
2. TIBC
3. Serum iron
4. % saturated
5. Cell appearance

1. Increased ferritin
2. Decreased TIBC
3. Increased serum iron
4. Increased % saturated
5. Ringed sideroblasts

59

Treatment for sideroblastic anemia?

Pyridoxine

60

Thalassemia is an anemia due to what?

Decreased synthesis of globin chains of hemoglobin

61

Why is there a decrease in globin chain synthesis in thalassemia?

Mutations in the genes for certain globin chains

62

Mutated carriers of thalassemia have protection against what?

Plasmodium falciparum malaria

63

Alpha thalassemia is due to what mutation?

Deletion in alpha-globin gene

64

How many alpha thalassemia genes are normally present?

4, 2 on each chromosome

65

One gene deletion of alpha-globin results in what?

Asymptomatic

66

Two genes deleted of alpha-globin results in what?

Mild anemia with elevated RBC count.

67

A cis-deletion of alpha-globin genes has an increased risk of what?

Severe thalassemia in offspring

68

Cis deletion of alpha globin is seen in what population?

Asians

69

Trans deletion of alpha globin gene is seen in what population?

Africans

70

Three alpha globin genes deleted results in what?

Severe anemia.

71

What type of hemoglobin dominates in 3 alpha gene deletions?

Tetramers of Beta chains (Hemoglobin H)

72

Hemoglobin H has what effect?

Damages RBC membranes

73

Four genes deleted usually results in what?

Death of fetus (hydrops fetalis)

74

What hemoglobin dominates in 4 alpha gene deletions?

Tetramers of gamma chains (Hemoglobin Barts)

75

Beta thalassemia is due to what mutation?

Point mutation in promoter or splicing sites.

76

What population usually has Beta thalassemia? 2

1. Africans
2. Mediterranean descent

77

What are the locations of alpha and beta globin genes?

1. Alpha = Chromosome 16
2. Beta = Chromosome 11

78

What is Beta thalassemia minor?

1 normal Beta gene
1 mutated Beta gene

79

How does beta-thalassemia minor present? 6

1. Asymptomatic
2. Increased RBC count
3. Hypochromic microcytic anemia
4. Increased in hemoglobin A2 and HbF
5. Decrease in hemoglobin A
6. Target cells

80

What is beta thalassemia major?

Homozygous mutated Beta globin genes

81

When do symptoms of beta-thalassemia present?

Several months after birth when HbF begins to decrease.

82

What forms in Beta thalassemia major?
What does this result in? (2)

Alpha tetramers

Ineffective erythropoiesis
Extravascular hemolysis (spleen removes RBC's)

83

How does the bone marrow respond to beta thalassemia major?
What does this result in? (3)

Massive erythroid hyperplasia

1. Hematopoiesis into skull (crewcut x-ray) and facial bones (chipmunk facies)
2. Hepatosplenomegaly
3. Risk of aplastic crisis with parvovirus B19

84

Chronic transfusions in Beta-thalassemia majorsometimes lead to what?

Secondary hemochromatosis (Extra iron in blood)

85

How does a smear in beta-thalassemia major appear?

Microcytic hypochromic RBC's with target cells and nucleated red blood cells

86

How do hemoglobin concentrations change in beta-thalassemia major?

Elevated HbA2 and HbF
little or no HbA

87

What is sickle cell thalassemia the result of?

Coinheritance of hemoglobin S genea dn thalassemic variant of the Beta-globin gene.

88

How does sickle cell's thalassemia compare to the other Beta-thalassemias?

Less severe than sickle cell

89

How does lead poisoning present? (LEAD)

1. Lead lines on gingiva (Burton's lines) and on metaphyses of long bones
2. Encephalopathy and Erythrocyte basophilic stippling
3. Abdominal colic and sideroblastic Anemia
4. Drops of wrist and foot (Dimercaprol and eDta to treat)

90

In terms of macrocytic anemia, what is the MCV?

Greater than 100

91

Three main causes of macrocytic anemia?

1. Folate deficiency
2. B12 deficiency
3. Orotic aciduria

92

Folate and B12 are necessary for synthesis of what?

DNA precursors

93

Folate circulates in serum as what form?

Methyltetrahydrofolate (methyl THF)

94

Removal of methyl group from methyl-THF allows for what?
What takes the methyl group?

Allows folate to participate in DNA synthesis

Vitamin B12

95

Vitamin B12 transfers methyl group to what?
To create what?

Homocysteine
Methionine

96

Lack of DNA precursors has what effect on RBC's?

Lack of nucleotide precursors --> RBC's can't divide enough --> Large RBC's.

97

Lack of DNA precursors has what effect on granulocytes?

Hypersegmented neutrophils

98

Overall, 3 areas that see a change due to folate or B12 deficiency?

1. RBC's --> Megaloblastic anemia
2. Granulocytes --> Hypersegmented neutrophils
3. Megaloblastic epithelial cells

99

3 other causes of macrocytic anemia without megaloblastic change? (3)

1. Alcoholism
2. Liver disease
3. Drugs

100

Dietary folate is obtained from what?

Green vegetables and fruit

101

Dietary folate is absorbed where?

Jejunum

102

Folate deficiency develops over what period of time?

Months

103

Causes of folate deficiency? (3)

1. Poor diet: Alcoholics and elderly
2. Increased demand: Pregnant, cancer, hemolytic anemia
3. Folate antagonists: Methotrexate, Dilantin

104

Clinical and lab findings of folate deficiency?
1. Appearance of RBC's and neutrophils
2. Tongue
3. Serum folate levels
4. Serum homocysteine
5. Methylmalonic acid levels

1. 1. Macrocytic RBC's and hypersegmented neutrophils
2. Glossitis
3. Decreased serum folate
4. Increased serum homocysteine
5. Normal methylmalonic acid

105

Dietary B12 enters the body how?

1. Salivary gland amylase liberates B12
2. B12 binds to R-binder (also from saliva)
3. In the duodenum, pancreatic proteases detach vitamin B12 from R-binder.
4. Vitamin B12 then binds intrinsic factor (from gastric parietal cells)
5. VitaminB12-Intrinsic factor is absorbed in ileum

106

Which is more common, folate or B12 deficiency?

Folate

107

How long does B12 deficiency take to develop?
Why?

Years
Huge hepatic stores of B12

108

What is most common cause of vitamin B12 deficiency?

Pernicious anemia

109

What is pernicious anemia due to?

Autoimmune destruction of parietal cells of stomach --> No intrinsic factor --> No absorbed B12

110

Other causes of Vitamin B12 deficiency? 5

1. Pancreatic insufficiency
2. Damage to terminal ileum (Crohn's, tapeworm)
3. Dietary deficiency in vegans
4. Auto-immune gastritis
5. Diphyllobothrium latum infections

111

Lab findings in B12 deficiency?
1. Smear appearance
2. Methylmalonic acid
3. Serum B12
4. Serum homocysteine

1. Macrocytic RBC's with hypersegmented neutrophils
2. High methylmalonic acid
3. low B12
4. High serum homocysteine

112

Clinical findings in B12 deficiency? 2

1. Glossitis
2. Subacute combined degeneration of spinal cord

113

Autoimmune gastritis is associated with what other effects? (3)

1. Achlorhydria (No HCl)
2. Anti-intrinsic factor and antiparietal cell Ab's
3. Increased incidence of gastric carcinoma

114

What test will determine if intrinsic factor alone will solve B12 deficiency?

Schilling Test

115

Orotic aciduria is due to what?

Genetic mutation in enzyme that synthesizes uridine from orotic acid

116

How does orotic aciduria present?

Megaloblastic anemia that cannot be cured by folate or B12

117

Findings in orotic aciduria? (3)

1. Hypersegmented neutrophils
2. Glossitis
3. Orotic acid in urine

118

Normocytic anemia is characterized how?

MCV of 80 to 100

119

What is normocytic anemia due to? (2)

increased peripheral destruction or underproduction of RBC's

120

What distinguishes whether a normocytic anemia is due to increased peripheral destruction or underproduction of RBC's?

Reticulocyte count

121

Reticulocytes are what?
How are they identified?

Young RBC's from the bone marrow
Larger cells with bluish cytoplasm

122

Normal reticulocyte count is what?

1-2%

123

RBC lifespan is how long?
What percentage of RBC's are removed per day?

120 days
1-2%

124

How can you determine if a healthy marrow is responding correctly to anemia?

Reticulocyte count greater than 3%

125

Reticulocyte count is corrected for by doing what?

Multiplying reticulocyte count by Hct/45

126

Corrected count >3% indicates what?

Good marrow resonse --> peripheral destruction

127

Corrected count <3% indicates what?

Poor marrow response --> Underproduction

128

Peripheral RBC destruction is divided into what two types?

Extravascular and Intravascular

129

Extravascular hemolysis involves RBC destruction by what?

Reticuloendothelial system (macrophages of the spleen, liver, and lymph nodes)

130

In extravascular hemolysis, macrophages consume RBC's, what do the parts of the RBC become?
Globin?
Heme?
Iron?
Protoporphyin?

Globin --> Amino acids
Heme --> Iron and protoporphyrin
Iron --> Recycled
Protoporphyrin --> Unconjugated bilirubin --> Binds to albumin --> delivered to liver--> Conjugated --> Excreted in bile

131

Clinical and laboratory findings of extravascular hemolysis? (6)

1. Anemia
2. Splenomegaly
3. Jaundice due to unconjugated bilirubin
4. Bilirubin gallstones
5. Marrow hyperplasia with RC of >3%
6. increased LDH

132

Intravascular hemolysis involves destruction of RBC's where?

Within vessels

133

Clinical and laboratory findings of intravascular hemolysis? (5)

1. Hemoglobinemia
2. Hemoglobinuria
3. Hemosiderinuria
4. Decreased serum haptoglobin
5. Increased LDH

134

What are the 3 main extravascular hemolysis normocytic anemias?

1. Hereditary spherocytosis
2. Sickle Cell anemia
3. Hemoglobin C

135

Hereditary spherocytosis is a inherited defect of what?
Specifically? (3)

RBC cytoskeleton-membrane tethering proteins

1. Ankyrin
2. Spectrin
3. Band 3.1

136

What happens to the RBC's in hereditary spherocytosis

Membrane blebs are formed and lost over time --> Cells become round --> Can't maneuver in spleen --> Splenic macrophages consume --> Anemia

137

Lab findings of hereditary spherocytosis? (3)

1. Spherocytes with loss of central pallor
2. Increased RDW: Older cells smaller than newer
3. Increased MCHC: Loss of space --> Increased Hb concentration

138

Clinical findings of hereditary spherocytosis:

1. Splenomegaly
2. Jaundice with unconjugated bilirubin
3. Increased risk for bilirubin gallstones
4. Increased risk of parvovirus B19 infection

139

What test diagnoses hereditary spherocytosis:

Osmotic fragility test: Spherocytes in hypotonic solution will burst

140

Treatment for hereditary spherocytosis?
What does this result in?

Splenectomy
Anemia resolves --> Spherocytes still exist --> Howell-Jolly bodies emerge on blood smear

141

Sickle cell anemia is due to what?

Autosomal recessive mutation in Beta chain of hemoglobin (glutamic acid [hydrophilic] to valine [hydrophobic]

142

Sickle cell gene is carried by 10% of what descent?
Purpose

African

Protective against falciparum malaria

143

Homozygous sickle cell gene results in what % of HbS?

90%

144

What does HbS do when deoxygenated?

Polymerizes --> Aggregates into needle like structures --> Sickle cells form

145

Increased risk of sickling is in what conditions? (3)

1. Hypoxemia
2. Dehydration
3. Acidosis

146

What hemoglobin form protects against sickling?

HbF

147

What treatment will increase HbF levels in sickle cell patient?

Hydroxyurea

148

Reversible sickling results in what? (3)

1. Extravascular hemolysis: Damaged RBC membranes are removed --> 3 symptoms
2. Intravascular hemolysis: Damaged RBC's dehydrate --> hemolysis
3. Massive erthroid hyperplasia

149

Result of amssive erythroid hyperplasia in sickle cell patients? (4)

1. Hematopoiesis in skull --> Crewcut on x-ray
2. Hematopoiesis in facial bones --> Chipmunk facies
3. Extramedullary hematopoiesis with hepatomegaly
4. Risk of aplastic crisis with parvovirus B19

150

Irreversible sickling leads to complications of what?

Vaso-occlusion

151

Complications of vasoocclusion include? 5

1. Dactylitis
2. Autosplenectomy
3. Acute chest syndrome
4. Pain crisis
5. Renal papillary necrosis

152

What is dactylitis?

Swollen hands and feet due to infarcts in bones

153

What are consequences of autosplenectomy in sickle cell patients?

1. Increased risk of infection with encapsulated organisms
2. Increased risk of salmonella paratyphi osteomyelitis
3. Howell-Jolly bodies on blood smear

154

What is most common cause of death in sickle cell kids?

H. influenzae infection due to autosplenectomy

155

What is most common cause of death in adult sickle cell patients?

Acute chest syndrome

156

Sickle cell trait is the presence of what alleles?

One mutated and one normal Beta chain

157

Sickle cell trait has what % of HbS?

Less than 50

158

Where do people with HbS less than 50% experience sickling?

Renal medulla due to extreme hypoxia nad hypertonicity

159

Laboratory findings in sickle cell?

1. Sickle cells and target cells (Disease only)
2. Metabisulfite screen: Causes HbS RBC's to sickle (Both)
3. Hb electrophoresis to confirm presence of HbS

160

Full disease Sickle cell has what array of Hb's?

90% HbS
8% HbF
2% HbA2
No HbA (No Beta globin chains)

161

Trait sickle cell has what array of Hb's?

55% HbA
43% HbS
2% HbA2

162

What is hemoglobin C the result of?
Specifically?

Autosomal recessive mutation in Beta chain of hemoglobin

Gluatmic acid to lysine

163

How does hemoglobin C present?

Mild anemia with extravascular hemolysis

164

What is the dead giveaway in HbC lab?

HbC crystals in RBC's on a smear

165

What are the 5 normocytic anemias with predominant intravascular hemolysis?

1. Paroxysmal nocturnal hemoglobinuria
2. Glucose-6-Phosphate dehydrogenase
3. Immune hemolytic anemia
4. MIcroangiopathic hemolytic anemia
5. malaria

166

What is paroxysmal nocturnal hemoglobinuria due to?

Acquired defect in myeloid stem cells --> Absent glycosylphosphatidylinositol (GPI) --> Cells can be destroyed by complement

167

What normally protects blood cells from complement mediated damage? 2
How?

DAF and MIRL

Inhibits C3 convertase

168

DAF and MIRL are secured to RBC membrane by what?

GPI

169

In PNH, when does intravascular hemolysis occur?
Why?

Usually at night during sleep

Mild respiratory acidosis during shallow breathing of sleep --> Activates complement --> RBC's, WBC's, and plateltes are lysed

170

What are lab tests for PNH? 5

1. Hemoglobinemia
2. Hemoglobinuria
3. Hemosiderinuria
4. Sucrose test
5. Acidified serum test/flow cytometry for lack of CD55/DAF on blood cells

171

Main cause of death in PNH patients?

Thrombosis of hepatic, portal, or cerebral veins

172

Why does thrombosis occur in PNH?

Destroyed platelets release their contents into circulation --> Induce thrombosis

173

Complication of PNH? (2)

1. Iron deficiency anemia
2. Acute myeloid leukemia

174

Glucose-6-phosphate dehydrogenase deficiency is due to what?

X-linked recessive disorder resulting in reduced half life of G6PD --> Cells susceptible to oxidative stress

175

How do RBC's deal with oxidative stressors like H2O2? 3

1. Glutathione neutralizes H2O2 --> Glutathione becomes oxidized
2. G6PD generates NADPH
3. NADPH reduces glutathione to regenerate reduced glutathione

176

What are the two major variants of G6PD?

1. African variant: Mildly reduced G6PD --> Mild intravascular hemolysis
2. Mediterranean variant: Markedly reduced G6PD --> Marked intravascular hemolysis

177

Carriers of G6PD are protective against what?

Falciparum malaria

178

Oxidative stress has what effect on Hb?

Precipitates them into Heinz bodies

179

Causes of oxidative stress? (3)

1. Infection
2. Drugs (primaquine, sulfa, dapsone)
3. Fava beans

180

Heinz bodie are removed from RBC's by what?

Splenic macrophages which causes lysis

181

What does G6PD deficiency present as after exposure to oxidative stress? (2)

1. Hemoglobinuria
2. Back pain

182

What is used to screen for G6PD?

Heinz preparation

183

Immune hemolytic anemia (IHA) is mediated by what? 92)

IgG or IgM destruction of RBC's

184

IgG IHA usually involves what type of hemolysis?

Extravascular

185

IgG in IHA does what?

IgG binds RBC's in warm temp of central body (warm agglutinin) --> Membrane of antibody coated RBC consumed by splenic macrophages --> Spherocytes form

186

What is IHA IgG associated with? (3)
Which one is most common?

SLE (most common)
CLL
Drugs: Penicillin and cephalosporins

187

How do drugs cause IgG IHA? (2)

1. Drug attaches to RBC membrane --> Antibody binds to drug membrane complex
2. Drug induces production of autoantibodies that bind self antigens

188

Treatment of IgG IHA (5)

1. Quit the problem drug
2. Steroids
3. IVIG
4. Splenectomy

189

Purpose of giving IVIG to IgG IHA patient?

Splenic macrophages like to consume this most

190

IgM mediated IHA involves what type of hemolysis?

Intravascular

191

How does IgM cause IHA?

IgM binds RBC's --> Fixes complement in cold temp of extremities (Cold agglutinin)

192

IgM mediated IHA is associated with what two infections?

1. Mycoplasma pneumoniae
2. Infectious mononucleosis

193

What is used to diagnose IHA?

Coomb's test

194

Direct Coombs test confirms what?
How does it do so?

Presence of antibody coated RBC's

Anti-IgG added to patient's RBC's --> Agglutination if RBC's are already coated with Ab's

195

Indirect Coombs test confirms what?
How does it do so

Presence of antibodies in patient serum

Anti-IgG and test RBC's are mixed with patient serum --> Agglutination occurs if serum antibodies are present

196

Microangiopathic hemolytic anemia is what?

Intravascular hemolysis that occurs to RBC's as they pass through ciruclation

197

What are the results of microangiopathic hemolytic anemia? (2)

1. Iron deficiency anemia
2. Chronic hemolysis

198

What types of patients get microangiopathic hemolytic anemia?

1. Microthbomi patients (TTP-HUS, DIC, HELLP)
2. Prosthetic heart valves
3. Aortic stenosis

199

What do patients with MHA have as special cells?

Schistocytes

200

Malaria is what?

Infection of RBC's and liver with plasmodium

201

What transmits malaria?

Female anopheles mosquito

202

What happens to RBC's in malaria?
What does this result in?

They rupture as part of plasmodium life cycle

1. intravascular hemolysis
2. cyclical fever

203

P. falciparum fever frequency?

Daily

204

P. vivax and p. ovale fever frequency?

Every other day

205

What happens to spleen in malaria?

Consumes infected RBC's --> Mild extravascular hemolysis --> Splenomegaly

206

Anemia due to underproduction is characterized how?

Low reticulocyte count

207

Etiologies of underproduction anemia? 3

1. Causes of micro and macrocytic anemias
2. Renal failure (decreased EPO)
3. Damage to bone marrow precursor cells

208

Anemias due to underproduction include? 3

1. Parvovirus b19
2. aplastic anemia
3. Myelophthisic process

209

Parvovirus B19 infects what cells?
What effect does this have?

Progenitor red cells

Halts erythropoiesis --> Significant anemia in setting of preexisting marrow stress

210

What is treatment for parvovirus B19?

Supportive

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Aplastic anemia is what?
What does that result in? (2)

Damage to Hematopoietic stem cells

Pancytopenia
Low reticulocyte count

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Etiologies of aplastic anemia? (4)

1. Drugs
2. Chemicals
3. Viruses
4. Autoimmune damage

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Biopsy of aplastic anemia will show what?

Empty fatty marrow

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Treatment of aplastic anemia? (2)

1. Cessation of any causative drugs
2. Supportive care of transfusions and marrow-stimulating factors

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last resort of aplastic anemia treatment?

Bone marrow transplant

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Myelophthisic process of anemia involves what?

Pathologic process (cancer) that replaces bone marrow --> Impair hematopoiesis --> Pancytopenia