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Hematology 2 > Ch. 19 - Disorders of Iron and Heme Metabolism > Flashcards

Ch. 19 - Disorders of Iron and Heme Metabolism Flashcards

1
Q

The anemias associated with iron and heme typically
are categorized as anemias of ________ _______ resulting
from the lack of raw materials for hemoglobin assembly.

A

impaired production

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2
Q

Inadequate production of ____________ leads to diminished
production of heme and thus hemoglobin, but with a relative
excess of iron.

A

protoporphyrin

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3
Q

The result of inadequate production of protoporphyrin

A

sideroblastic anemia

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4
Q

functional molecules

A

heme-based cytochrome,
muscle myoglobin,
hemoglobin

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5
Q

Iron may be unavailable for incorporation into

heme because of _____________ or __________

A

inadequate stores of body iron
impaired
mobilization.

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6
Q

The anemia associated with inadequate stores is

termed:

A

iron deficiency anemia

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7
Q

the anemia resulting

from impaired iron mobilization is known as

A

anemia of chronic

inflammation

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8
Q

an example of a chronic inflammation condition

A

rheumatoid arthritis

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9
Q

the iron
supply is adequate and mobilization is unimpaired but an
intrinsic RBC defect prevents production of protoporphyrin or
incorporation of iron into it, the resulting anemia is called:

A

sideroblastic anemia

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10
Q

refers to the presence of nonheme iron in

the developing RBCs

A

sideroblastic

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11
Q

develops when the INTAKE OF IRON IS INADEQUATE to meet a standard level of demand, when the NEED FOR IRON EXPANDS, when there is IMPAIRED ABSORPTION, when
there is CHRONIC LOSS OF HEMOGLOBIN from the body

A

iron deficiency anemia

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12
Q

Approximately how much of iron is lost from the body each day?

A

1 mg of iron

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13
Q

Iron is lost from the body mainly in the _____________________ and __________.

A

mitochondria of desquamated skin and sloughed intestinal epithelium

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14
Q

Causes of iron deficiency when the level of iron intake

is inadequate to meet the needs of an expanding erythron

A

-infancy
(especially in prematurity), childhood, and adolescence
-pregnancy and nursing

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15
Q

Causes of impaired absorption

A
  • celiac disease
  • diseases that decrease stomach acidity
  • gastrectomy or bariatric surgeries
  • medications such as antacids
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16
Q

hemolysis that results in the loss of small amounts of

heme iron from the body over a prolonged period of time

A

chronic hemorrhage

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17
Q

Excessive

heme iron can be lost through?

A

-chronic gastrointestinal bleeding from ulcers
-gastritis due to alcohol or aspirin ingestion,
-tumors
parasitosis
-diverticulitis
-ulcerative colitis
-hemorrhoids

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18
Q

In women, what conditions such as can also lead to heme iron loss?

A

-prolonged menorrhagia (heavy menstrual
bleeding)
-fibroid tumors
-uterine
malignancies

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19
Q

Individuals with chronic
intravascular hemolytic processes, such as ________________, can develop iron deficiency due to the
loss of iron in hemoglobin passed into the urine.

A

paroxysmal nocturnal

hemoglobinuria

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20
Q

iron is distributed among three compartments, what are these?
(1) the storage compartment, principally as ferritin in
the bone marrow macrophages and liver cells; (2) the transport
compartment of serum transferrin; and (3) the functional
compartment of hemoglobin, myoglobin, and cytochromes.

A

(1) the storage compartment, principally as ferritin in
the bone marrow macrophages and liver cells
(2) the transport
compartment of serum transferrin
(3) the functional
compartment of hemoglobin, myoglobin, and cytochromes.

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21
Q

True or false. Hemoglobin and intracellular ferritin constitute nearly 85% of
the total distribution of iron.

A

False. *95%

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22
Q

The body strives to maintain iron balance by accelerating
absorption of iron from the intestine through a decrease
in the production of ________ in the liver.

A

hepcidin

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23
Q

What stage of iron deficiency is defined by the exhaustion of the
storage pool of iron?

A

Stage 2

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24
Q

What stage of iron deficiency is characterized by a progressive loss
of storage iron?

A

Stage 1

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25
Q

(Stage 2) The serum iron and serum ferritin levels
decrease, whereas ______________, an indirect
measure of transferrin, increases

A

total iron-binding capacity (TIBC)

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26
Q

(Stage 2) ___________________, the porphyrin

into which iron is inserted to form heme, begins to accumulate.

A

Free erythrocyte protoporphyrin (FEP

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27
Q

(Stage 2) ____________ stain of the

bone marrow in stage 2 shows essentially no stored iron

A

Prussian blue

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28
Q

True or false. Iron deficiency in stage 2 is subclinical, and
testing is not likely to be undertaken.

A

True

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29
Q

What stage of iron deficiency is frank anemia?

A

Stage 3

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30
Q

(Stage 3) True or false. The hemoglobin
concentration and hematocrit are high relative to the reference
ranges.

A

False. *low :))

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31
Q

(Stage 3) True or false. FEP and transferrin receptor levels continue to decrease.

A

False *increase

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32
Q

Nonspecific symptoms of anemia

A

fatigue and weakness

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33
Q

A severe sign due to due to iron deficiency in the rapidly proliferating
cells of the alimentary tract

A

sore

tongue (glossitis)

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34
Q

A severe sign characterized by inflamed cracks at

the corners of the mouth

A

angular cheilosis

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35
Q

may be seen if the deficiency

is long-standing

A

Koilonychia

spooning of the fingernails

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36
Q

cravings for

nonfood items

A

pica

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37
Q

Craving for ICE

A

pagophagia

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38
Q

_______________________

can lead to a loss of nearly 900 mg of iron,

A

pregnancy and nursing

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39
Q

Growth requires
a. _____ for the cytochromes of all new cells, b. ________for new
muscle cells, and c. __________ in the additional RBCs needed
to supply oxygen for a larger body.

A

a. iron
b. myoglobin
c. hemoglobin

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40
Q

True or false. Cow’s milk

is a good source of iron

A

False

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41
Q

iron supplementation is also

recommended for breastfed infants after how many months of age?

A

6 months

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42
Q

___________ and __________ can lead to gastritis and

chronic bleeding.

A

-Regular aspirin
ingestion
-alcohol consumption

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43
Q

Iron deficiency is associated with infection by hookworms. Give two examples.

A

Necator americanus and Ancylostoma duodenale

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44
Q

Iron deficiency is also associated with infection
with other parasites, such as: __________, ___________, and __________ in which the heme iron
is lost from the body due to intestinal or urinary bleeding.

A

Trichuris trichiura, Schistosoma

mansoni, and Schistosoma haematobium

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45
Q

___________ develops when RBCs are hemolyzed
by foot-pounding trauma and iron is lost as hemoglobin
in the urine

A

“Marching anemia”

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46
Q

The tests for iron deficiency can

be grouped into three general categories:

A
  • screening
  • diagnostic,
  • specialized.
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47
Q

When iron deficient erythropoiesis is under way, the CBC

results begin to show evidence of ________, ________ and, _________

A

anisocytosis, microcytosis,

and hypochromia

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48
Q

The classic picture of iron
deficiency anemia in stage 3 includes a decreased _________
level.

A

hemoglobin

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49
Q

An RDW greater than ___ is expected and may precede

the decrease in hemoglobin.

A

15%

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50
Q

As the hemoglobin level continues to fall, microcytosis and hypochromia become more prominent, with
progressively declining values for ____, _____, and _____

A

MCV, MCH, and MCHC

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51
Q

A low
________________ confirms a diminished rate of effective
erythropoiesis, because this is a nonregenerative anemia

A

absolute reticulocyte count

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52
Q

_____________ may be present,
particularly if the iron deficiency results from chronic bleeding,
but this is not a diagnostic parameter.

A

Thrombocytosis

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53
Q

True or false. White blood cells

(WBCs) are typically normal in number and appearance.

A

True

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54
Q

Iron
deficiency should be suspected when the CBC findings show a
hypochromic, microcytic anemia with an (a. elevated b. decreased) RDW but no
consistent shape changes to the RBCs.

A

a. elevated

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55
Q

____________ remain the backbone for diagnosis of iron deficiency

A

Iron studies

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56
Q

______________ is

a measure of the amount of iron bound to transferrin in the serum.

A

Serum iron

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57
Q

______ is an indirect measure of
transferrin and the available binding sites for iron in the
plasma.

A

TIBC

58
Q

True or false. Ferritin is not truly an extracellular protein.

A

True *because it provides an intracellular storage repository for metabolically active iron

59
Q

_____________ is an

easily accessible surrogate for stainable bone marrow iron

A

Serum ferritin

60
Q

Serum ferritin

and serum iron values are (a. increased b.decreased) in iron deficiency anemia

A

b. decreased

61
Q

Transferrin levels (a. increase b. decrease) when the hepatocytes detect low
iron levels, and research shows that this is a transcriptional and
posttranslational response to low iron levels.12

A

a. increase

62
Q

It is important that specimens for iron studies are drawn

while ______ and when levels are highest.

A

fasting

early in the morning

63
Q

Iron absorbed from a meal can falsely

(a.elevate b. decrease) levels

A

a. elevate

64
Q

The reticulocyte

hemoglobin value is analogous to the ___, but for reticulocytes.

A

MCH

65
Q

The ___ is the average weight of hemoglobin per cell

across the entire RBC population

A

MCH

66
Q

The ________________ is able to assess iron deficient erythropoiesis within days
as the first iron deficient cells leave the bone marrow.

A

reticulocyte hemoglobin value

67
Q 
Even in stage 2 of iron
deficiency, before anemia is apparent, the reticulocyte hemoglobin
will be (a. low b. high)
A

a. low

68
Q

Test results for

the accumulated porphyrin precursors to heme are (a. elevated b. decreased)

A

a. elevated

69
Q

In
the absence of iron, FEP may be preferentially chelated with
zinc to form __________________

A

zinc protoporphyrin (ZPP)

70
Q

The FEP and zinc

chelate can be assayed ____________

A

fluorometrically

71
Q

A __________________ provides a less invasive and less expensive
diagnostic assessment.

A

therapeutic trial of iron

72
Q

With routine stains, the iron deficient
bone marrow appears a. ___________ early in the progression of
the disease, with a decreased b. ________________ ratio as a
result of increased erythropoiesis.

A

a. hyperplastic

b. myeloid-to-erythroid

73
Q

As the disease progresses,
__________ subsides, and the profound deficiency of iron leads
to slowed RBC production.

A

hyperplasia

74
Q

_________________ (i.e.,

rubricytes) show the most dramatic morphologic changes

A

Polychromatic normoblasts

75
Q

Without the pink provided by hemoglobin, the cytoplasm

remains ____ after the nucleus has begun to condense.

A

bluish

76
Q

The
cell membranes appear irregular and are usually described as
_______

A

shaggy

77
Q

The first therapy for iron deficiency is to treat any underlying
contributing cause, such as?

A

hookworms, tumors, or ulcers.

78
Q

As
in the treatment of simple nutritional deficiencies or increased
need, dietary supplementation is necessary to replenish the
body’s iron stores. Oral supplements of _______________________________are the standard
prescription.3

A 
ferrous sulfate (3
tablets/day containing 60 mg of elemental iron)
79
Q

The supplements should be taken on an

(a. empty b. full) stomach to maximize absorption

A

a. empty

80
Q

What can be used in rare cases in which intestinal absorption
of iron is impaired, as with gastric achlorhydria?

A

parenteral

administration of iron dextrans

81
Q

(Response to Treatment) The reticulocyte hemoglobin will correct within how many days?

A

2 days

82
Q

(Response to Treatment) The reticulocyte counts (relative and absolute) begin to
increase within how many days?

A

5 to 10 days

83
Q

The anticipated rise in hemoglobin
appears in a. ______ (how many weeks), and levels should return to
normal for the individual by about b. ______ (how many months) after the initiation
of adequate treatment

A

a. 2 to 3 weeks

b. 2 months

84
Q

The peripheral blood film and
indices still reflect the microcytic RBC population for several
months, but the _________ population eventually predominates.

A

normocytic

85
Q

Iron therapy must continue for another ____________ (how many months)
to replenish the storage pool and prevent a relapse.

A

3 to 4 months

86
Q

This anemia represents the most common

anemia among hospitalized patients

A

Anemia of Chronic Inflammation

87
Q

Who was the first to suggest that although the underlying
diseases seem quite disparate, the associated anemia may be
from a single cause, proposing the concept of anemia of
chronic disease

A

Cartwright

88
Q

True or false. Chronic
blood loss is not among the conditions leading to the anemia
of chronic disease.

A

True

89
Q

The central feature

of anemia of chronic inflammation

A

sideropenia

90
Q

The cause of anemia of chrosnic inflammation is now understood to be
largely what?

A

impaired ferrokinetics

91
Q

hormone produced by
hepatocytes to regulate body iron levels, particularly absorption
of iron in the intestine and release of iron from macrophages

A

Hepcidin

92
Q

exports iron from enterocytes into the plasma, reducing

the amount of iron absorbed into the blood from the intestine

A

Transmembrane protein: Ferroportin

93
Q

When body iron
levels a. _______, hepcidin production by hepatocytes decreases,
and b. ________ export more iron into the plasma

A

a. decrease

b. enterocytes

94
Q

When iron levels
are high, hepcidin increases, enterocytes export (a. more b. less) iron into
the plasma, and macrophages and hepatocytes retain iron.

A

b. less

95
Q

an iron-binding protein in

the granules of neutrophils

A

Lactoferrin

96
Q

Acute phase reactants

A

hepcidin, lactoferrin, ferritin

97
Q

The peripheral blood picture in anemia of chronic inflammation
is that of a mild anemia with hemoglobin concentration
usually ______ g/dL and without reticulocytosis.

A

9 to 11

98
Q

Because hepatocyte production
of transferrin is regulated by iron levels, the low TIBC
(an indirect measure of transferrin) reflects the (a.abundant b. diminished) iron
stores in the body.

A

a. abundant

99
Q

Iron deficiency
anemia and anemia of chronic inflammation can be distinguished
in such situations by measuring _______________.

A

serum (soluble) transferrin

receptors

100
Q

Therapeutic administration of ____________ can correct

anemia of chronic inflammation

A

erythropoietin

101
Q

Trulaloo or false. The best course of treatment in anemia of chronic inflammation is effective control or
alleviation of the underlying condition.

A

True

102
Q

True or false. As in iron deficiency, the anemia of chronic inflamm may be microcytic and hypochromic.

A

True

103
Q

True or false. In contrast to iron deficiency, however, iron is abundant
in the bone marrow in the anemia of chronic inflamm.

A

True

104
Q

a cofactor
in the first step of porphyrin synthesis which glycine is condensed with succinyl coenzyme A to form
aminolevulinic acid

A

Pyridoxine

105
Q

Certain drugs that can induce sideroblastic

anemia

A

chloramphenicol or isoniazid

106
Q

A toxin that interferes with porphyrin synthesis

A

Lead

107
Q

The most critical steps when lead interferes with porphyrin synthesis

A
  1. The conversion of aminolevulinic acid to porphobilinogen;
    the result is the accumulation of aminolevulinic acid.
  2. The incorporation of iron into protoporphyrin IX by ferrochelatase
    (also called heme synthetase); the result is accumulation
    of iron and protoporphyrin.
108
Q 
Accumulated aminolevulinic acid is measurable
in the (a. stool b. blood c. urine)
A

c. urine

109
Q

protoporphyrin is measurable in an

extract of RBCs as___ or ___.

A

FEP or ZPP

110
Q

Anemia, when present in lead poisoning, is most often
normocytic and normochromic; however, with chronic exposure
to lead, a ________, _________clinical picture may be
seen.

A

microcytic, hypochromic

111
Q

Hereditary Disorders Included in Sideroblastic Anemias

A

X-linked

Autosomal

112
Q

The presence of a
hemolytic component is supported by studies showing impairment
of the _______________by lead, which makes
the cells sensitive to oxidant stress as in glucose-6-phosphate
dehydrogenase deficiency

A

pentose-phosphate shunt

113
Q

chronic

poisoning results in ______ of the marrow

A

hypoplasia

114
Q

a classic finding associated with lead toxicity

A

Basophilic

stippling

115
Q

Lead
inhibits _______________, an enzyme involved in the
breakdown of ribosomal ribonucleic acid (RNA) in reticulocytes

A

pyrimidine 5′-nucleotidase

116
Q

In the case of lead,
___________________________are often used to
chelate the lead present in the body so that it can be excreted
in the urine

A

salts of ethylenediaminetetraacetic acid

117
Q

The term ________ is most often

used to refer to the hereditary conditions

A

porphyria

118
Q

The fluorescence of
the accumulated compounds can be used diagnostically as
described earlier for FEP. In a sample of bone marrow, the
erythroblasts will be _______ under a fluorescent microscope.

A

bright red

119
Q

It occurs when there is a need for repeated transfusions, as in
the treatment of anemias such as thalassemia.

A

Accumulation of excess iron

120
Q

It is when the iron present
in the transfused RBCs exceeds the usual 1 mg/day of iron
typically added to the body’s stores by a healthy diet.

A

transfusion-related hemosiderosis

121
Q

may develop as a result of mutations

affecting the proteins of iron metabolism

A

Hemochromatosis

122
Q 
a gene on the short arm of chromosome
6 that encodes an HLA class I–like molecule that is
closely linked to HLA-A
A

HFE

123
Q

The most common of the two
mutations substitutes tyrosine for ________ at position 282
(Cys282Tyr)

A

cysteine

124
Q

the other mutation substitutes _________ for histidine

at position 63 (His63Asp).

A

aspartate

125
Q

The normal ____ protein binds

β2-microglobulin intracellularly.

A

HFE

126
Q

Interaction of HFE with _____________ reduces transferrin binding to the receptor, inhibiting
cellular iron absorption

A

transferrin

receptor 1

127
Q

The _______________
either does not bind β2-microglobulin and thus does not reach
the cell surface, or does not bind the transferrin receptor 1 if
it does reach the cell surface

A

mutated HFE molecule

128
Q

The (a. active b. passive) transport of iron into the
plasma seems to be crucial in the pathophysiology of hereditary
hemochromatosis.

A

a. active

129
Q

the gene that codes

for hemojuvelin

A

HJV (HFE2)

130
Q

In hepatocytes, what substances regulate hepcidin expression

A

-iron-bound transferrin
-HFE
-transferrin
receptor 2
-hemojuvelin

131
Q

The first

cellular reaction to excess iron is?

A

form hemosiderin

132
Q

essentially a degenerate and non–metabolically active form of
ferritin

A

hemosiderin

133
Q

the traditional characterization

of hemochromatosis

A

“bronzed diabetes”

134
Q

occurs more frequently in patients with hemochromatosis.

A

Hepatocellular carcinoma

135
Q

The phenotypic expression of the tissue damage
in hereditary hemochromatosis is more
common in (a.men b. women)

A

a. men

136
Q

In classic hereditary hemochromatosis,
individuals usually harbor ______ g of iron by the time their
disease becomes clinically evident at the age of 40 to 60 years

A

20 to 30 g

137
Q

Withdrawal of blood
by phlebotomy provides a simple, inexpensive, and effective
means of removing iron from the body. The regimen calls
for weekly phlebotomy early in treatment to remove about
___ mL of blood per treatment

A

500

138
Q

iron-chelating drug that is a classic treatment for people who cannot be treated by phlebotomy

A

Desferrioxamine

139
Q

When stained using Prussian blue, the iron appears in
deposits around the nucleus of the developing cells. These cells
are called?

A

ringed sideroblasts

140
Q

In the pathogenesis of the anemia of chronic inflammation,

hepcidin levels:

A

Increase during inflammation and reduce iron

absorption from enterocytes

141
Q

Sideroblastic anemias are anemias that result from:

A

Failure to incorporate iron into protoporphyrin IX

Hematology 2 (12 decks)

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