iron pres swetha
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Transcript of iron pres swetha
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IRON IN HEALTHIRON IN HEALTHAND DISEASEAND DISEASE
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IRON METABOLISMIRON METABOLISM
INTRODUCTORY BACKGROUNDINTRODUCTORY BACKGROUND
Essential element in all living cells
Transports and stores oxygen
Integral part of many enzymes
Usually bound to other molecules
Quantity of body iron carefully
controlled
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BODY IRON DISTRIBUTIONBODY IRON DISTRIBUTION
A. Metabolically Active Iron:
Haemoglobin
Serum iron bound to a protein
transferrin in blood
Tissue Iron: in cytochromes andenzymes
Myoglobin: oxygen reserve in muscles
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APPROXIMATE DISTRIBUTION OFAPPROXIMATE DISTRIBUTION OF
BODY IRON IN A MANBODY IRON IN A MAN
Hemoglobin 2000mgStorage Iron 1000mg
Myoglobin iron 130mg
Labile Pool 80mg
Other tissue Iron 8mgTransport Iron 3mg
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BODY IRON DISTRIBUTIONBODY IRON DISTRIBUTION
B. Storage Iron:
Ferritin: found in blood, tissue fluids, andcells
Haemosiderin: found in macrophages andassessed by staining bone marrow withPrussian Blue stain
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DIETARY SOURCES OF IRONDIETARY SOURCES OF IRON
Inorganic Iron eg lentils Organic iron eg beef
DAILY IRON REQUIREMENT 10-15mg/day (5-10% absorbed)
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IRON ABSORPTIONIRON ABSORPTION Iron kept soluble and in ferrous state by
gastric acid
Absorbed mainly in duodenum
Quantity absorbed regulated by enterocyte
Multiple proteins involved in control of iron
transport Haem iron enters the enterocyte through
different process than inorganic iron
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ABSORPTION OF IRON
Haem
Fe+++
Fe++
Ferritin
Tf
Tf-
Fe+++ Fe++Fe++
Enterocyte GutGut
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IRON ABSORPTION (cont)IRON ABSORPTION (cont)
Transferrin bound iron in plasma
delivered to body cells according to
cellular iron requirements
Note:
Only 20% of plasma bound iron derivedfrom gut. Most plasma iron is derived from
breakdown of senescent red cells.
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WHAT YOU NEED TO KNOWWHAT YOU NEED TO KNOW
Daily requirements and dietary sources ofiron
Where iron is absorbed in the gut Control of iron balance at level of enterocyte
How body stores of iron are assessed
Proteins involved in regulation of iron
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IRON DEFICIENCYIRON DEFICIENCY
Commonest cause of anaemia worldwide
Cause of chronic ill health
May indicate the presence of importantunderlying disease eg. blood loss from
tumour
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EVOLUTION OF IRONEVOLUTION OF IRON
DEFICIENCY ANAEMIADEFICIENCY ANAEMIA
Earliest stage : depletion of body
iron stores only
Biochemical iron deficiency
without anaemia
Iron deficiency anaemia
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CLINICAL FEATURES IRONCLINICAL FEATURES IRON
DEFICIENCYDEFICIENCY
Symptoms eg. fatigue, dizziness, headache
Signs eg. pallor, glossitis, angularcheilosis, koilonychia, Plummer Vinsonsyndrome
Koilonychia Glossitis
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Angular Cheilosis
or Stomatitis
CLINICAL FEATURES OF IRON DEFICIENCYCLINICAL FEATURES OF IRON DEFICIENCY
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Absent iron stores in bone marrowABSENT IRON STORES IN BONEABSENT IRON STORES IN BONE
MARROW IN IRON DEFICIENCYMARROW IN IRON DEFICIENCY
Iron deficiencyNormal control
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PRINCIPLES OF TREATMENTPRINCIPLES OF TREATMENT
Use oral iron ( not enteric coated tablets )
Replace iron deficit in total :
Restore haemoglobin and MCV to normal
Replenish iron stores
Establish and treat the cause
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LOOK FORLOOK FOR
THE CAUSETHE CAUSEOF IRONOF IRON
DEFICIENCYDEFICIENCY
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CAUSES OF IRON DEFICIENCYCAUSES OF IRON DEFICIENCY
Increased physiologic demand
eg. pregnancy, lactation, rapid
growth
Blood loss from GI tract, uterus,
haemoglobinuria
Malabsorption
Diet
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WHAT YOU NEED TO KNOWWHAT YOU NEED TO KNOW
Symptoms and signs of iron deficiency
Laboratory diagnosis of iron deficiency Differential diagnosis of a microcytic
hypochromic anaemia
Importance of finding a cause for irondeficiency
Principles of treatment
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IRON OVERLOADIRON OVERLOAD
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CAUSES OF IRON OVERLOADCAUSES OF IRON OVERLOAD
Hereditary haemochromatosis
Multiple transfusions Liver disease
Prolonged use medicinal iron
Ineffective erythropoiesis African Iron Overload
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EFFECTS OF IRON OVERLOAD
Non-transferrin-bound iron
(NTBI) circulates in the plasma
Excess iron promotes
the generation of free
hydroxyl radicals,
propagators of oxygen-related tissue damage
Liver cirrhosis/
fibrosis/cancer
Insoluble iron complexes
are deposited in body
tissues and end-organtoxicity occurs
Diabetes
mellitusGrowth
failure
Capacity of serum transferrin
to bind iron is exceeded
Iron overload
Cardiac
failureInfertility
HSC
senescence
(Fenton Reaction)
O2- + H2O2 O2+OH- + HO
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WHEN DOES IRON BECOME AWHEN DOES IRON BECOME A
PROBLEM?PROBLEM?
Normally 2.5 3.5g of iron in thebody.
Tissue damage when total body ironis 7 15 g
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TREATMENT AND PREVENTIONTREATMENT AND PREVENTION
Phlebotomy until ferritin