Chapter 102. Aplastic Anemia, Myelodysplasia, and Related Bone Marrow Failure Syndromes (Part 12)

Pure Red Cell Aplasia: Treatment History, physical examination, and routine laboratory studies may disclose an underlying disease or a suspect drug exposure. Thymoma should be sought by radiographic procedures. Tumor excision is indicated, but anemia does not necessarily improve with surgery. The diagnosis of parvovirus infection requires detection of viral DNA sequences in the blood (IgG and IgM antibodies are commonly absent). The presence of erythroid colonies has been considered predictive of response to immunosuppressive therapy in idiopathic PRCA.Red cell aplasia is compatible with long survival with supportive care alone: a combination of erythrocyte transfusions and iron chelation. ...
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Chapter 102. Aplastic Anemia, Myelodysplasia, and Related Bone Marrow Failure Syndromes (Part 12) Chapter 102. Aplastic Anemia, Myelodysplasia, and Related Bone Marrow Failure Syndromes (Part 12) Pure Red Cell Aplasia: Treatment History, physical examination, and routine laboratory studies may disclosean underlying disease or a suspect drug exposure. Thymoma should be sought byradiographic procedures. Tumor excision is indicated, but anemia does notnecessarily improve with surgery. The diagnosis of parvovirus infection requiresdetection of viral DNA sequences in the blood (IgG and IgM antibodies arecommonly absent). The presence of erythroid colonies has been consideredpredictive of response to immunosuppressive therapy in idiopathic PRCA. Red cell aplasia is compatible with long survival with supportive carealone: a combination of erythrocyte transfusions and iron chelation. For persistentB19 parvovirus infection, almost all patients respond to intravenousimmunoglobulin therapy (for example, 0.4 g/kg daily for 5 days), although relapseand retreatment may be expected, especially in patients with AIDS. The majorityof patients with idiopathic PRCA respond favorably to immunosuppression. Mostfirst receive a course of glucocorticoids. Also effective are cyclosporine, ATG,azathioprine, cyclophosphamide, and the monoclonal antibodydaclizumab, anantibody to the IL-2 receptor. PRCA developing on erythropoietin therapy shouldbe treated with immunosuppression and withdrawal of erythropoietin. Myelodysplasia Definition The myelodysplasias (MDSs) are a heterogeneous group of hematologicdisorders broadly characterized by cytopenias associated with a dysmorphic (orabnormal appearing) and usually cellular bone marrow, and by consequentineffective blood cell production. A clinically useful nosology of these entities wasfirst developed by the French-American-British Cooperative Group in 1983. Fiveentities were defined: refractory anemia (RA), refractory anemia with ringedsideroblasts (RARS), refractory anemia with excess blasts (RAEB), refractoryanemia with excess blasts in transformation (RAEB-t), and chronicmyelomonocytic leukemia (CMML). The World Health Organizationclassification (2002) recognizes that the distinction between RAEB-t and acutemyeloid leukemia is arbitrary and groups them together as acute leukemia, notesthat CMML behaves as a myeloproliferative disease, and separates refractoryanemias with dysmorphic change restricted to erythroid lineage from those withmultilineage changes (Table 102-5). Table 102-5 World Health Organization Classification ofMyelodysplastic Syndromes Disease Freque Blood Bone Prognos ncy Findings Marrow is Findings Refractory 5–10% Anemia Erythro Protractanemia (RA) id dysplasia ed course No or only rare blasts Leukem (RARS) ≥15% ia in ~1–2% ringed sideroblasts ringed sideroblasts nias (2 or 3 ia in ≥10% of(RCMD-RS) lineages) cells in ≥2 lineages No or rare blasts ≥15% ringed No sideroblasts Auer rods 109/L Auer rods monocytes Refractory Cytope Uniline Progressanemia with excess nias age or ive BM failureblasts-2 (RAEB-2) multilineage 5–19% Leukem dysplasia blasts ia in ~33% 10– ±Auer 19% blasts rods ±Auer Auer rods No Auer rods MDS with Unkno Anemia Nl or Longisolated del(5q) wn increased survival