Page 231 - Essential Haematology

Chapter 16 Myelodysplasia / 217

bruising or bleeding (Fig. 16.1 ). In some patients problems. The function of the neutrophils, mono-
transfusion - dependent anaemia dominates the cytes and platelets is often impaired so that infec-
course, while in others recurring infections or spon- tions and bleeding may occur out of proportion to
taneous bruising and bleeding are the major clinical the severity of the cytopenia. The spleen is not

usually enlarged.
It is important to remember that dysplastic
features in bone marrow may be seen in a wide
range of conditions such as excess alcohol intake,
megaloblastic anaemia, parvovirus, recovery from
cytotoxic chemotherapy and granulocyte colony -
stimulating factor (G - CSF) therapy. Th ese must
be ruled out before making a diagnosis of MDS
and diagnostic tests may need to be repeated over
time in some patients.

Laboratory fi ndings
Peripheral b lood
Pancytopenia is a frequent fi nding. The red cells are

usually macrocytic or dimorphic but occasionally
hypochromic; normoblasts may be present. Th e
reticulocyte count is low. Granulocytes are often
reduced in number and frequently show lack of

granulation (Fig. 16.2 ). Their chemotactic, phago-
cytic and adhesive functions are impaired. Th e
Pelger abnormality (single or bilobed nucleus) is
(a) often present. The platelets may be unduly large or

small and are usually decreased in number but in
10% of cases are elevated. In poor prognosis cases
variable numbers of myeloblasts are present in the
blood.

Bone m arrow

The cellularity is usually increased. Multinucleate

normoblasts and other dyserythropoietic features
(e.g. internuclear bridges, nuclear budding) are seen
(Fig. 16.2 ). The appearance of ring sideroblasts is

(b) caused by iron deposition in the mitochondria of

erythroblasts. The granulocyte precursors often

Figure 16.1 Myelodysplasia. (a) A 78 - year - old male
show defective granulation and may be diffi cult to
patient with refractory anaemia had recurring
distinguish from monocytes. Megakaryocytes are
infections of the face and maxillary sinuses associated
abnormal with micronuclear, small binuclear or
with neutropenia (haemoglobin 9.8 g/dL; white cells
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1.3 × 10 /L; neutrophils 0.3 × 10 /L; platelets polynuclear forms (Fig. 16.2 ). A small number of

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38 × 10 /L). (b) Purpura in a 58 - year - old female with dysplastic cells may be seen in marrow from healthy

refractory anaemia (haemoglobin 10.5 g/dL; white cells elderly individuals so at least 10% of the cells in a
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2.3 × 10 /L; platelets 8 × 10 /L). lineage should be dysplastic in order to consider the