This document discusses classification and causes of anemia, focusing on iron deficiency anemia. It describes the normal iron metabolism process and requirements. Causes of iron deficiency anemia include blood loss, insufficient dietary iron intake, and malabsorption. Laboratory findings of iron deficiency anemia show a low hemoglobin with decreased MCV, MCH, and MCHC, known as a hypochromic microcytic blood film. The bone marrow appears hypercellular with increased red blood cell precursors that stain negative for iron.
Classification and causes of iron deficiency anemia
1. Classification of anemia
Causes of anemia
-Blood loss.
-Iron deficiency.
-Infection.
-RBC destruction (hemolysis)
e.g. G6PD.
-B12 and Folate deficiency.
Red cells size and their indices
-Hb concentration and Hematocrit
-MCV, MCH, MCHC.
↓MCV
-IDA
-Thal
↑MCV
-B12
-Folat
Normal MCV
-hemolytic
anemia
2. Iron deficiency anemia
Normal iron metabolism:
-The primary function is oxygen transport.
-Iron is absorbed by duodenum and jejunim
-Average total body iron content 3500-4000 mg.
-Approximately 2/3 found in hemoglobin,
-Iron is also stored in RE cells (BM, Spleen and liver)
as hemosiderin and ferratin.
-Also iron found in myglobin and myeloperoxidase
and in certain electron transfer.
-Iron is more stable in ferric state (Fe+++
) than in
ferrous state (Fe++
).
5. Iron Absorption
1-2 mg only
Plasma Fe
Transferrin carriers
4 mg
Body stores
1000 mg (M)
300-500 mg (F)
Myglobin
300 mg
20 mg Fe
Returned to immature RBC
in BM
RBC
2500 mg
R.E. 20 mg
Released daily
Via RE system
90% extra vascular
5-10% intra vascular
Loss (from GI tract)
1-2 mg daily
Daily Fe++
turnover continuous process
6. Dietary iron:
Iron is present in food as ferric hydroxides (ferric-protein
complexes and hem-protein complexes).
-meat, liver
-vegetables, eggs.
-The average diet contains 10-15mg and only 5-10% is normally
absorbed.
Iron requirements:
It varies depending on sex and age:
Male/female 0.5-1 mg/day
Pregnant female 1-2 mg/day
Children 0.5 mg/day
7. Clinical features:
• When ID is developing, the RE stores (hemosiderin and
ferritin) become completely depleted before anemia occurs.
• At an early stage, no clinical abnormalities.
• Later, patient may develops general symptoms and signs of
anemia.
• In severe case of IDA ridged or spoon nails.