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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
                                              9
                            9

                      1.3    ×   10  /L; neutrophils 0.3    ×   10  /L; platelets   polynuclear forms (Fig.  16.2 ). A small number of

                            9
                      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
                                          9
                            9


                      2.3    ×   10  /L; platelets 8    ×   10  /L).     lineage should be dysplastic in order to consider the
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