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46 / Chapter 3 Hypochromic anaemias

Iron r efractory i ron d efi cency 5 Bone marrow storage (reticuloendothelial) iron is
a naemia ( IRIDA ) normal but erythroblast iron is reduced (Table
3.7 ).
Rare auosomal recessive cases of hypochromic
microcytic anaemia have been described caused by Th e pathogenesis of this anaemia appears to be
inherited mutations of matriptase 2 or DMT - 1 related to decreased release of iron from macro-

genes (Figs 3.4 and 3.5 ). There may be a haemato- phages to plasma because of raised serum hepcidin
logical response to intravenous but not oral iron. levels, reduced red cell lifespan and an inadequate

Anaemia of c hronic d isorders
Table 3.6 Causes of the anaemia of chronic

One of the most common anaemias occurs in
disorders.
patients with a variety of chronic infl ammatory and
malignant diseases (Table 3.6 ). Th e characteristic Chronic infl ammatory diseases
features are: Infections (e.g. pulmonary abscess,
tuberculosis, osteomyelitis, pneumonia,
1 Normochromic, normocytic or mildly hypochro-
bacterial endocarditis)
mic (MCV rarely < 75 fL) indices and red cell
Non - infectious (e.g. rheumatoid arthritis,
morphology.
systemic lupus erythematosus and other
2 Mild and non - progressive anaemia (haemoglobin
connective tissue diseases, sarcoidosis,
rarely < 9.0 g/dL) – the severity being related to Crohn ’ s disease, Gaucher ’ s disease)
the severity of the disease.
Malignant diseases

3 Both the serum iron and TIBC are reduced.

Carcinoma, lymphoma, sarcoma

4 The serum ferritin is normal or raised.

Table 3.7 Laboratory diagnosis of a hypochromic anaemia.
Chronic
infl ammation Thalassaemia Sideroblastic
Iron defi ciency or malignancy trait ( α or β ) anaemia
MCV/ Reduced in Normal or mild Reduced; very Usually low in
MCH relation to reduction low for degree congenital type but
severity of of anaemia MCV usually raised
anaemia in acquired type
Serum iron Reduced Reduced Normal Raised
TIBC Raised Reduced Normal Normal
Serum ferritin Reduced Normal or raised Normal Raised
Bone marrow iron stores Absent Present Present Present
Erythroblast iron Absent Absent Present Ring forms
Haemoglobin Normal Normal Hb A 2 raised Normal
electrophoresis in β form

MCH, mean corpuscular haemoglobin; MCV, mean corpuscular volume; TIBC, total iron - binding capacity.