IRON DEFICIENCY ANEMIA/ ANEMIA OF CHRONIC DISEASE

16 Pages·2006·0.64 MB·English

Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON DEFICIENCY ANEMIA/
ANEMIA OF CHRONIC DISEASE
ANEMIA
Definition
• Decrease in the number of circulating
red blood cells
• Most common hematologic disorder by
far
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
ANEMIA
Causes
• Blood loss
• Decreased production of red blood cells
(Marrow failure)
• Increased destruction of red blood cells
– Hemolysis
• Distinguished by reticulocyte count
– Decreased in states of decreased production
– Increased in destruction of red blood cells
ANEMIA
Causes -Decreased Production
• Cytoplasmic production of protein
– Usually normocytic (MCV 80-100 fl) or
microcytic (MCV < 80 fl)
• Nuclear division/maturation
– Usually macrocytic (MCV > 100 fl)
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
ANEMIA
Causes -Cytoplasmic Protein Production
• Decreased hemoglobin synthesis
– Disorders of globin synthesis
– Disorders of heme synthesis
• Heme synthesis
– Decreased Iron
– Iron not in utilizable form
– Decreased heme synthesis
IRON DEFICIENCY ANEMIA
Prevalence
Country Men (%) Women Pregnant
(%) Women (%)
S. India 6 35 56
N. India 64 80
Latin America 4 17 38
Israel 14 29 47
Poland 22
Sweden 7
USA 1 13
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON
• Functions as electron transporter; vital for life
• Must be in ferrous (Fe+2) state for activity
• In anaerobic conditions, easy to maintain
ferrous state
• Iron readily donates electrons to oxygen, (cid:206)
superoxide radicals, H O , OH• radicals
2 2
• Ferric (Fe+3) ions cannot transport electrons or
O
2
• Organisms able to limit exposure to iron had
major survival advantage
IRON
Body Compartments -75 kg man
Stores
1000 mg
Absorption < 1 mg/day
Tissue
4 mg
170 mg Excretion < 1 mg/day
Red Cells
2400 mg
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON CYCLE
CIRCULATING RBCs
MONONUCLEAR
PHAGOCYTES
Fe Fe
ptor Fe Fe
e
ec Fe Fe
R
errin Fe Ferritin Ferritin Fe Fe FeFFee Ferritin
sf
n
a slow
Tr Hemosiderin
F Fe
e
RBC PRECURSOR
Fe
Fe
TRANSFERRIN
INTRACELLULAR IRON TRANSPORT
Fe+2
Transferrin
Transferrin receptor
H+
H+
Lysosome
H+ H+ Fe+2
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON
Causes of Iron Deficiency
• Blood Loss
– Gastrointestinal Tract
– Menstrual Blood Loss
– Urinary Blood Loss (Rare)
– Blood in Sputum (Rarer)
• Increased Iron Utilization
– Pregnancy
– Infancy
– Adolescence
– Polycythemia Vera
• Malabsorption
– Tropical Sprue
– Gastrectomy
– Chronic atrophic gastritis
• Dietary inadequacy (almost never sole cause)
• Combinations of above
DAILY IRON REQUIREMENTS
Pregnancies
2.5
y)
a 2
n /d
og
Irm 1.5
orbed ment ( 1
Absuire
q 0.5
e
R
0
0 2 10 14 20Ag27e 29 32 34 40 49 55 65 Males
Males Females
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON ABSORPTION
16
14
) 12
y
a
d 10
/
g
m 8
(
n 6
o
r 4
I
2
0
Iron in Diet Iron Iron Uptake Iron Absorbed
Solubilized
GI ABSORPTION OF IRON
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
FERRITIN/TRANSFERRIN REGULATION
IRON ABSORPTION
100
10
Iron
1 Absorbed
(mg/day)
0.1
0.01
0.1 1 8 10 20 80 100 200
Iron Ingested (mg/day)
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON DEFICIENCY ANEMIA
Progression of Findings
• Stainable Iron, Bone Marrow Aspirate
• Serum Ferritin - Low in Iron Deficiency
• Desaturation of transferrin
• Serum Iron drops
• Transferrin (Iron Binding Capacity) Increases
• Blood Smear - Microcytic, Hypochromic;
Aniso- & Poikilocytosis
• Anemia
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Iron Deficiency Anemia/Anemia of Chronic Tuesday, February 10, 2004 –10:00 am
Disease
IRON STORES
Iron Deficiency Anemia
Stores
0 mg
Absorption 2-10 mg/day
Tissue
3 mg
170 mg Excretion Dependent on Cause
Red Cells
1500 mg
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