iron deficiency anemia part 1 Flashcards
what are the stages of deficiency?
depletion of stores
morphological abnormalities in blood film and BM
anaemia
anemia is the final expression of the deficiency state
how is haem synthesised ?
incorporation of iron into protophyrin in nucleated red cells in bone marrow
what are the differential diagnosis of microcytic hypochromic anemia ?
sideroblastic anemia
iron deficiency anemia
thalassemia
anemia of chronic disease
what is the average iron store in a healthy individual?
40-50 mg/kg
what form is iron stored in in RBCS?
haemoglobin
in what form is iron stored in in muscles ?
myoglobin
in what form is iron stored in in all tissues ?
cytochromes and iron sulphur proteins
in what form is iron stored in in the liver spleen and bone marrow ?
ferritin and haemosiderin
when do iron requirments increase ?
menustration
pregnancy
early infancy
adolescent growth spurt
how is iron transported ?
transferrin
lactoferrin in milk
what kind of transport is transferrin responsible for ?
extracellular transport
what is the expression of TFR in iron deficiency anemia like ?
cellular expression increases if cells have inadequate stores and decrease if the iron replete
what can differentiate between iron deficiency anemia and anaemia of chronic disease ?
soluble transferrin receptor , they increase as an early indicator of iron deficiency anemia but are off normal levels in anemia of chronic disease
what is the role of TFR-2 ?
senses the degree of saturation of the transferrin and is a key regulator of hepcidin synthesis
what is haemosidrin ?
partially degraded ferritin along with lysosomes
what are the causes of iron deficiency ?
limited supply
increased physiological requirements
blood loss
what could the limited supply be due to ?
- inadequate dietary iron take
- decreased iron absorption
what are the causes of decreased iron absorption ?
coeliac disease
gastrectomy
what is the occult blood test ?
is a test used to detect any evidence of blood in stool
what are the clinical features of iron deficiency anemia ?
- tiredness, exertional dyspnoea
- angular stomatits
- kolionychias
what does the blood film in iron deficiency anemia look like ?
microcytic hypo chromic anemia
presence of pencil cells
target cells
low MCH MCV MCHC
what is TIBC?
total iron binding capacity
what is meant by transferrin saturation ?
percentage of saturation transferrin is
the serum iron divided by TIBC x 100
what value of transfferin saturation would indicate iron deficiency anemia ?
15%
what iron stain is used in bone marrow aspirate ?
perls prussian blue stain
how would you correct the iron deficiency ?
- oral iron supplements 200mg 3 times a day for 4-6 months ( ferrous sulphate )
- parenteral iron
what are the side effects of oral iron therapy ?
GI side effects
what is the affection in sideroblastic anemia ?
iron accumulation in the RBC
what does haemosedrin look like on film ?
yellow on unstained film
positive with iron stain
what is the most common cause of chronic blood loss causing anemia ?
hookworm
what type of cells are found in the film of iron deficiency anemia ?
pencil cells
target cells
what are the results of iron studies in iron deficiency anemia ?
low serum iron low transferrin levels low serum ferritin increased total iron binding capacity increased soluble transferrin receptor
what is diagnostic of sideroblastic anemia in blood film ?
sideroblastic ring
what is the lifespan of a RBC ?
120 days
what is the relationship between hepcidin and iron ?
when hepcidin increases iron decreases
what are the clues in diagnosing sideroblastic anemia ?
1- atypically high ferritin and iron
2- may present as iron deficiency as it shows microcytic hypochromic anemia
3- resistant to inteensive iron treatment
