Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hematalogy Lecture > Test 3: Disorders of Iron and Heme Metabolism > Flashcards

Test 3: Disorders of Iron and Heme Metabolism Flashcards

1
Q

The average adult has total body iron content of _______ mg
____ is found in hemoglobin
____ is found in bone marrow, liver, and spleen

A

3500-4000 mg

• 2/3
•1/3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where does the majority of iron come from?

A

Recycling 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The minimum daily iron requirement for adults is ___ mg

A

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Daily iron requirements are affected by what three things? 

A
  • chronic blood loss
    • Increase need
    • Inadequate intake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Serum Fe levels exhibit both monthly and diurnal (daily) variation.

When should labs be drawn for iron studies?

A

First thing in the morning and fasting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Iron is ingested in foods as Fe__+ (_________) form. 

A

3, ferric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Stomach acid reduces Iron to Fe__+ (________) form so it can be absorbed in the gut.

A

2, ferrous

  • gut mucosal cells oxidize back to Fe3+ form, enters the bloodstream, and is transported by transparent for distribution to buy tissues, or for storage in the bone marrow, liver, or spleen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

______ atoms of ferric iron can combine to one transferrin molecule.

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

____% of iron carried by transferrin is used for heme synthesis

A

80

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Iron not utilized by erythropoiesis is stored as _________ or _________. 

A

Ferritin or hemosiderin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

____________ is the major form of storage iron. It is water soluble and is easily utilized by the body. Seen only via electron microscope. 

A

Ferritin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

__________ + ___________ = ferritin

A

Apoferritin, Fe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

____________ is not water soluble and is less readily available to the body.

A

Hemosiderin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

This iron form represents Aggregates of iron and can be seen with Prussian blue stain
Can become available in iron deficient patients

A

Hemosiderin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What stain is used for hemosiderin?

A

Prussian blue stain for iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is included in the standard Fe panel?

A

-serum Fe
-TIBC
-Serum ferritin
-Percent transferrin saturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

This is a measure of transferrin–bound iron

A

Serum Fe
(NR=50 - 160 ug/dL)?

*assays has poor sensitivity for IDA, due to the disease’s various stages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Total amount of iron that can be bound by transferrin. It is effectively an indirect measurement of transferrin concentration

A
  • total iron binding capacity (TIBC)
    (NR= 250 - 400 ug/dL) 
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

increased TIBC means the body….

A

wants more iron! 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

TIBC:

Add known amount access iron to patients Sera to saturate all transferrin molecules present then remove excess and…. 

A

Measure what remains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

TIBC does what in IDA? 

A

???

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Transferrin Increases when Fe __________. 

A

Decreases.

-In order for body to scavenge up any available iron atoms 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Immunoassay which evaluates body iron stores. Despite the fact that ferritin is intracellular its concentration in circulation is usually proportional to the amount of iron in storage

A

Serum ferritin 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the advantage and disadvantage of serum ferritin? 

A

This is the first lab test to become abnormal when iron stores decrease (Even before RBC morphology changes) 

Ferritin is an acute phase reactant so it’s elevated during any inflammatory response 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the normal range for serum ferritin? 

A

40-400 ng/mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What might a patient’s ferritin level be with an exacerbation of SLE who also had an IDA? 

A

Normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Is functionally measured as the maximum amount of iron that is Bound in plasma or serum

A

% transferrin saturation

(in other words, “how many transferrin molecules are full”?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is percent transferrin saturation calculated? 

A

= serum iron / TIBC x 100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the normal range for % transferrin saturation? 

A

20-55% saturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What would percent transferrin be in IDA?

A

Decreased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What would percent transferrin saturation be in iron overload? 

A

Increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How do the Free Erythrocyte Protoporphyrin (FEP) or Zinc  Protoporphyrin (ZPP) tests work?

A

-when iron is not available to be incorporated into protoporphyrin ring to form heme, access portoporphyrins form
-these excess rings complex with zinc to form zinc protoporphyrin (ZPP)
-The ZPP value correlates inversely with the ferritin level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

A The worse the IDA, the _______________ the ZPP level.

A

Higher

More Protoporphyrin is left over to bind with zinc (due to decreased iron binding)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is a good test to differentiate IDA from thalassemia? 

A

Free erythrocyte protoporphyrin (FEP) or Zinc protoporphyrin (ZPP) test *

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How is FCP/ZPP test measured? And what is the normal range?

A

Fluorometrically

< 80 ug/dL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Measurement of transferrin receptors

A

Soluble transferrin receptor test 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Soluble transferrin receptors are ____________ related to the amount of body iron. 

A

Inversely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

With the lack of intracellular iron, regulatory proteins increase the synthesis of ______________ receptors.

A

transferrin 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Severe IDA __________ transferrin receptors

A

Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What test can be used to distinguish IDA from anemia of chronic inflammation? 

A

Soluble transferrin receptor test

  • soluble transferrin receptor test levels remain normal in anemia of chronic Inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the definition of anemia according to WHO criteria for men and women? 

A

• Men: Hb < 13.0 g/dL or Hct < 40%
• Women: Hb < 12.0 g/dL or Hct < 36%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are useful measurements For assessing anemia?

A

• MCV (mean corpuscular volume): 80-100 f
• RDW (red cell distribution width): increased value indicates
RBCs of differing sizes
• Reticulocytes: indicates the bone marrow’s ability to respond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Worldwide what is the most common type of anemia that affects 2 billion people? 

A

Iron deficiency anemia (IDA)


How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are the three ways IDA can occur?

A

-State of increased physiologic demand (growth or pregnancy)
-inadequate intake (deficient diet or absorption issues)
-chronic blood loss (Ulcers, menstrual flow, parasites) 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What age does prenatal iron stores run out at?

A

Three months (3-6 months) 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what are common Symptoms of all severe anemia?

A

dyspnea and dizziness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

IDA can cause the compulsive desire to eat a single food, or more commonly a non-food item. Is the term for this?

A

Pica

48
Q

Flattened spooned fingernails

A

Koilonychiq (symptom of IDA)

49
Q

 what are the typical RBC morphology change seen in IDA? 

A

Microcytic and hyperchromic
Moderate Anisocytosis and increased RDW
Pilokocytosis with codocytes, elliptocytes or ovalocytes, and dacrocytes 

50
Q

And RPI less than two means? 

A

Bone marrow is not responding effectively

51
Q

At what IDA stage does the Iron labs come back abnormal?
chem panel abnormal? 

A

Stage two
Not until stage three

(Very important* Look at IDA stages chart)

52
Q

How iS IDA treated?

A

-treat underlying contributing cause
-Give oral iron supplements and treat symptoms as needed
Transfusions only given in life-threatening emergencies 

53
Q

When treating ADA, retic count should increase within ______ hours reaching maximum in _______ days. 

A

48 hours, about 10 days

54
Q

______________ population of RBCs become evident as new “iron normal” RBC‘s increase in numbers, while the old “iron deficient” RBCs die off.

A

Dimorphic

55
Q

What is the second most common anemia? 

A

Anemia of chronic inflammation (Anemia of chronic disease)

-Associated with chronic infections and other states of chronic inflammation

56
Q

What is the essential feature of anemia of chronic inflammation?

A

Sideropenia (Iron deficiency) With abundant iron stores

  • Not due to bleeding, hemolysis, or bone marrow replacement by cancer or a leukemia
57
Q

What is the pathophysiology of ACI? 

A

Appears to be due to the body withholding iron from inflamed cells, pathogenic microbes, and tumor cells, in an attempt to starve them to death
*regulated by hepcidin 

58
Q

A hormone produced by hepatocytes and regulates body iron levels
-Reduces the amount of iron absorbed from intestines
-influences the ability of macrophages and parasites to retain iron

A

Hepcidin

59
Q

When iron levels are high, hepcidin Increases, and ___________ retain iron (and vice versa) 

A

Macrophages

60
Q

Hepcidin is also an ____________ reactant, So during Inflammation (Unrelated to iron levels), There is a decrease in iron absorption and macrophages retain iron

A

Acute-phase 

61
Q

(Acute-phase reactant) it is an iron binding protein in neutrophilic granules (Importance in phagocytosis). During Inflammation, lactoferrin is released into plasma and scavenges available iron.

A

Lactoferrin

(RBCs do not have lactoferrin receptors)

62
Q

Acute phase reactant that also binds iron in plasma.

A

Ferritin

(RBCs lack ferritin receptors)

63
Q

In ACI low Iron is not the problem. What is?

A

Iron availability/release

64
Q

What is the first test to look at when determining ACI? 

A

TIBC (It would be decreased, with IDA it would be increased) 

65
Q

What are the clinical symptoms of ACI

A

-decrease serum iron and % Transferrin saturation
-Normal to increased ferritin levels
* TIBC decreased
-ZPP increased
-Transparent receptors are normal (decreased in IDA)
- Symptoms of the primary disorder

66
Q

Morphology lab findings and ACI…

A

-Mild to moderate norm-, norm- Anemia (Sometimes look micro, hypo)
-no Reticulocytosis 

67
Q

What is the treatment of ACI?

A

-treat the underlying condition (RA, TB, etc.)
-Can give EPO, but must also supply iron supplements concurrently (Otherwise could be fatal) 

68
Q

Decreased ferritin and increased TIBC….

IDA or ACI?

A

IDA (opposite for ACI) 

69
Q

Both IDA and ACI can be normal to decreased for MCV and MCHC. But bone marrow iron levels are decreased in which anemia?

A

IDA

70
Q

What type of patient population would be most likely at risk for ACI? 

A

Hospitalized

71
Q

Lead intoxication and hemachromatosis are both disorders of….

A

Iron metabolism

72
Q

Even if MCV is normal you can have microcytic RBCs. How? 

A

Due to MCV being an average

73
Q

Sideroblastic anemia is a diverse group of anemia that is characterized by:

A

-Hypochromic anemia
-Ineffective erythropoiesis
-An increase in serum and tissue iron
-The presence of ringed sideroblastic in the bone marrow
* very diverse group of disorders that can be inherited or acquired

74
Q

An enzyme disorder type of anemia in which the body has adequate iron which enters normoblasts, but is unable to incorporate it into hemoglobin

A
  • Sideroblastic anemias (SA) 
75
Q

Involves abnormalities of the enzymes regulating heme synthesis
-Identify deficiencies of Delta-ALA synthetase and uroporphyrinogen decarboxalace 

A

Sideroblastic anemias 

76
Q

What is an Identifying characteristic of Sideroblastic anemia? 

A

Ring sideroblastic (Iron is accumulated in the mitochondria that surround the nucleus) 

77
Q

Delta ALA synthase requires __________ as a coenzyme.

A

Pyridoxine/pyridoxal (B6)

78
Q

Normoblast Containing free Fe granules (Not yet incorporated into heme) in it’s mitochondria;  found in bone marrow (Not in peripheral blood)

A

Sideroblast 

79
Q

Mature RBC in peripheral blood containing free iron granules (aka. Siderotic granules or pappenheimer bodies)

A

Siderocyte

80
Q

Stain used for ringed sideroblasts?
Stain used for Pappenheimer bodies?

A

Prussian blue
Wrights stain

81
Q

Involves a defect of delta-ALA Ssynthase, very rare, genetic
-Heme synthesis is impaired as iron enters the erythroid precursor which cannot be incorporated in the molecule because the Portoporphyrin ring cannot be formed….. Iron builds up in the mitochondria

A

Hereditary sideroblastic anemia 

82
Q

What is the treatment for Hereditary sideroblastic anemias? 

A

B6 however many patients don’t respond.

Death typically due to iron overload problems

83
Q

Acquired sideroblastic anemia:
actually a type of myelodysplastic disorder (Which some considered to be a preleukemia)

A

Refractory anemia with ringed sideroblast (RARS) -

84
Q

What is the treatment for RARS? 

A

Treatment is rarely done because disease is usually non-progressive and non-incapacitating unless it converts to a leukemia

85
Q

type of Anemia that usually follows exposure to drugs or toxins (ethanol, Alcohol, Lead, and chemotherapeutic agents)

A

Secondary anemia

  • In alcoholics (Alcohol uses up B vitamin coenzymes so it causes a decrease in activity of heme synthesis enzymes)
86
Q

What are lab findings in sideroblastic anemia

A

- Micro, hypo with dimorphic population (Increased RDW)
-Anisocytosis, poilkilocytosis, target cells, pappenheimer bodies, and basophilic stippling 

87
Q

TIBC is ________ In sideroblastic anemias 

A

Normal to slightly decreased

88
Q

What is increased in sideroblastic anemia? 

A

Serum, serum iron, percent transferrin saturation

(A lot of iron laying around and not getting used) 

89
Q

What is the transferrin Receptor level usually in sideroblastic anemia?

A

Normal or decreased

90
Q

What are Pappenheimer bodies?

A

Iron

91
Q

Lead intoxication leads to _______________ anemia.

A

Sideroblastic

92
Q

Lead affects what three major tissues?

A

-Renal
-Hemaptopoetic (Lead inhibits activity of three enzymes in heme synthesis pathway)
-Central nervous system

93
Q

What are the three enzymes that lead negatively affects in heme synthesis pathway?

A

• BPG synthase
• Coproporphyrinogen oxidase
• Heme synthase/synthetase (aka.
Ferrochelatase.)

94
Q

What are the symptoms of lead intoxication?

A

-abdominal pain (Lead colic)
-Constipation and vomiting
-Muscle weakness and motor disturbances
-Leadline (Blue black deposit of lead sulfide in gums near teeth or in nail beds)
-Psychiatric disturbances, seizures, coma, and permanent mental retardation (severe cases) 
-lead can cross placenta

95
Q

Lab Morphology findings of lead intoxication…

A

Mild to moderate micro, hypo anemia in chronic exposure
Hallmark is basophilic stippling (but not always, they can be found in other anemia‘s but stippling is heavier in lead intoxication) 

96
Q

What are the lab findings consistent with lead intoxication?

A

Normal serum iron, Ferritin and TIBC; But increased FEP* (Pathway causes an over accumulation of protoporphyrin nine) 

97
Q

Lead intoxication has an increased RPI, meaning…

A

Anemia has a hemolytic component

98
Q

What is the treatment for lead intoxication

A

-Remove the source of lead
-Chelation therapy

99
Q

Lead intoxication interferes with incorporation of __________ in __________. 

A

Iron, heme 

100
Q

Porphyrias result in _____________ Hematopoiesis and sideroblastic anemia

A

Ineffective

  • Can be hereditary or acquired
101
Q

Group of disorders due to an impaired production of heme. 

A

Porphyrias

-when an enzyme is missing, the products from earlier stages in the pathway accumulate in the blood and may be excreted in urine or feces

102
Q

What conditions are associated with porphyrias?

A

Photo sensitivity, motor dysfunction, sensory loss, mental disturbances, and some abdominal pain

103
Q

What is the most common porphyria?

A

Acute intermittent Porphyria*

-Missing Enzyme in prophobilinogen deaminase
-Massive buildup of porphobilinogen and ALA in urine

104
Q

An inappropriate or abnormal accumulation of excess iron, resulting in tissue damage (stored in the liver, heart, and pancreas leading to organ damage)
-This can bronze skin pigmentation

A

Hemochromatosis

105
Q

Transferrin receptors appear to be permanently “turned on”. (It may be due to mutant hepcidin. The patient cannot become hypoferrimic when needed)
- Patient absorbs normal amount of iron, but they transport more of it into the plasma

A

Hereditary hemochromatosis (HH) 

106
Q

How common is hereditary hemochromatosis?

A

1:300 of northern European Caucasians
* One of the most frequent genetic diseases in this population

107
Q

 Hemachromatosis is due to a mutant gene linked to the HLA-A locus of chromosome _____ called the HFE Gene. 

A

6

108
Q

_____________ Hemachromatosis occurs secondary to other inherited hemolytic anemia‘s

A

Acquired

-Common characteristics are anemia, ineffective erythropoiesis, and iron overload
-Usually have multiple transfusions that leads to increased iron storage due to no mechanism for iron excretion

109
Q

What are the lab findings for patients with hemachromatosis?

A

-increased ferritin
-Increased hemosiderin
-Free iron increases (ferrous form)
-Ferrous iron + oxygen = super oxide and free radicals leading to cell death*


110
Q

all cells (except _____________) require iron, and have the potential for damage in hematochromtosis 

A

Mature RBCs

111
Q

Meadow chroma ptosis is most commonly seen in males ages of ______ years (But infant and juvenile forms do exist)

A

40-60

112
Q

What are the most common symptoms of hematochromotosis? 

A

Joint pain and chronic fatigue

Homozygous show cardiovascular disease, especially cardiac arrhythmias, liver cancer, osteoarthritis and even diabetes mellitus (Bronzed diabetes) which accounts for about 10% of all diabetes mellitus cases
(Can also Cause cases of cardiomegaly, early menopause, depression, infertility and impotence) 

113
Q

What is the first lab indication of hereditary hemochromatosis?
What is the criteria for diagnosis in females and males?

A

Increased percent transferrin saturation

Greater than 50% for females
Greater than 60% for males

114
Q

In patients with hemachromatosis serum iron is _______, And serum ferritin is_________.  Normal or _________ TIBC. 

A

Increased
Very elevated
Decreased

115
Q

TIBC is indirect estimate of amount of __________, Does the body need to make more of this under current circumstances

A

Transferrin 

116
Q

What two diseases are treated by aggressive therapeutic phlebotomy?

The goal is to have serum ferritin below ______ And percent transferrin saturation below _____%

A

-Hemachromatosis
-Polycythemia versa

(Blood cannot be donated)

50 ug/L, 80%

117
Q

What is the treatment for acute poisoning in hemachromatosis?

A

IV administration of desferoxamine (A chelating agent used to remove iron stores)

  • used when hemoglobin is less than 10 g/dL
    -Not as effective as simple bloodletting

Hematalogy Lecture (35 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions