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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myelodysplastic syndromes (SMD) were studied in 58 patients (37 men, 21 women; mean age 61 years, range 18-81) who were grouped according to FAB criteria (Table 1). None of them showed a secondary SMD to medullary toxic agents or cytostatic treatments although 5 presented concomitant neoplastic disease. Morphologic alterations in peripheral blood smears and bone marrow were registered by 3 hematologists working independently. The intracellular and extracellular iron deposits were evaluated in every case with Perls; peroxidase activity was determined in 16 patients and intraleucocitary alkaline phosphatase reaction was carried out in 17 patients. Twenty five patients (43%) had refractory anemia (RA); 10 (17%) sideroblastic anemia; 13 (25%) refractory anemia with excess of blasts (AREB); 3 (5%) AREB in transformation (AREB-T) and 7 myelomonocytic leukemia (LMMC). Clinical manifestations at diagnosis are described in Table 2. In the observation period there were cases of anemia requiring transfusion, bacterial infections, muco-cutaneous hemorrhage and hemorrhagic episodes in the central nervous system. In the bone marrow smears the cellularity was normal or increased in 53 cases and diminished in only 3. The degree of dysplastic characteristics (erythroid, granulocytic and megakaryocytic) ranged from low to severe. It was low in most of AR, being the erythroid population the most affected in AS and the granulocytic one in AREB and AREB-T. Patients with LMMC showed similar characteristics to those with myeloproliferative syndromes and the differential diagnosis were sometimes difficult, accounting for their separate inclusion in Table 4. Out of 23 patients, 5 presented clonal pathology detected in cytogenetic studies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Myelodysplastic syndrome: experience of the Study and Treatment of Bone Marrow Failure Group]. 213 Feb 4

The clinical, hematologic, and immunophenotypic features in 20 patients with Down's syndrome (DS) and acute leukemia were analyzed. Of the 20 patients, all 14 patients who were 3 years old and less were diagnosed as having acute megakaryoblastic leukemia (AMKL) by use of platelet-specific monoclonal antibodies and platelet peroxidase (PPO) reaction in electron microscopy. They were characterized by the presence of bone marrow fibrosis, having a history of myelodysplastic syndrome (MDS) and a poor response to chemotherapy. Only one patient has remained in continuous complete remission for more than 1 year. Acute leukemia in six patients who were older than 4 years was classified as common acute lymphoblastic leukemia antigen (CALLA)-positive acute lymphoblastic leukemia (ALL). In one of six patients classified as ALL, the leukemic blasts simultaneously expressed myeloid-associated surface antigens. All six patients achieved a complete remission and have remained in continuous complete remission and have remained in continuous complete remission from 10 to 52 months from the initial diagnosis. Although it has been suggested that the distribution of types of acute leukemia in patients with DS is similar to that in normal children, the present study shows that the distribution of acute leukemia types is quite different from that in patients without Down's syndrome.
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PMID:Down's syndrome and acute leukemia in children: an analysis of phenotype by use of monoclonal antibodies and electron microscopic platelet peroxidase reaction. 182 81

Cytogenetic analyses were performed on 12 adult patients with abnormal megakaryoblastic proliferation which was detected by ultrastructural cytochemical study (platelet peroxidase) and platelet-megakaryocytes-specific monoclonal antibodies (TP-80, Plt1, AN51, and KOR-77). The patients consisted of two patients with myelodysplastic syndromes (MDS), three with acute megakaryoblastic leukemia (AMKL), six with megakaryoblastic transformation in Philadelphia-positive chronic myelogenous leukemia (CML-meg-BC), and one case of chronic myeloproliferative disorder (CMPD). Among them, an inversion of the long arm of chromosome 3 [inv(3)(q21q26)] was found in one AMKL patient with a normal platelet count. Chromosome change at band 3q26 was also found in one MDS patient without thrombocythemia. Furthermore, the long arm of chromosome 13, where rearrangements in myelofibrosis are clustered (13q12----q22) was seen in one MDS patient. Trisomoy of chromosome 19 was found in one AMKL patient and three CML-meg-BC patients. These findings indicate that cytogenetic abnormalities involving 3q26, 13q, and trisomy 19 are associated with hematologic neoplasia with megakaryocytic lineage in adult patients, although these abnormalities were not related to the survival of the patients. During the period of this study, two acute myelogenous leukemia patients (AML-M2 and AML-M5b) with chromosome rearrangements at band 3q21 and thrombocythemia were found, indicating that chromosome abnormality at band 3q21 is related to quantitative platelet dysfunction, whereas that at 3q26 is related to hematologic malignancies with a proliferation of megakaryocytic lineage.
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PMID:Cytogenetic findings in adult acute leukemia and myeloproliferative disorders with an involvement of megakaryocyte lineage. 229 63

The Technicon H6000 hematology blood counter is a fully automated analyzer which provides, in addition to conventional hematological blood values (i.e. RBC, PLT, etc.), a differential count of WBCs based on a combination of cytochemistry (peroxidase content) and cell volume analysis. Because of these characteristics, the H6000 quantitizes, as part of the full differential count, the number and percentage of "large unstained cells" (LUCs), i.e. large peroxidase-negative circulating elements with a cell volume above a predetermined threshold established for the lymphocytes of normal subjects. We evaluated the H6000 printouts (scattergrams) of 29 patients with myelodysplastic syndromes and of 12 other patients with transient cytopenias. The most important and constant diagnostic features for myelodysplastic syndromes were the increased proportion of LUCs and, in some cases, the high monocyte count, which are both automatically provided by the instrument.
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PMID:The technicon H6000 automated hematology analyzer in the diagnosis and classification of the myelodysplastic syndromes. 233 93

Cytogenetic, immunologic, and electron microscopic studies were performed on the blast cells of 28 pediatric patients with Down's syndrome, 13 with acute leukemia (DS-AL) and 15 with transient myeloproliferative disorders (DS-TMD). Clonal chromosome abnormalities were found in the cells of all patients with DS-AL but not those with DS-TMD. The younger ages and higher hemoglobin concentrations, platelet counts, and WBC counts of DS-TMD patients provided a clinical contrast with the frankly leukemic cases. Myelodysplastic syndrome, characterized by a small percentage of leukemic blast cells, was observed in 11 of the 13 patients with DS-AL compared with none in the DS-TMD group. Electron microscopy disclosed a positive platelet peroxidase reaction in each of the 11 DS-TMD patients and in nine of the 13 DS-AL patients. Immunologic studies revealed antiplatelet-megakaryocyte antigens on the blast cells of the majority of patients in both study groups. Our findings suggest that the blast cells in cases of DS-AL and DS-TMD arise from cells of the megakaryocytic lineage or from a myeloid progenitor with the capacity for megakaryocytic differentiation. The high risk of the development of AL in patients with DS who are less than 3 years old may be related to increased megakaryocyte proliferation in this age group.
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PMID:Cytogenetic findings and clinical features in acute leukemia and transient myeloproliferative disorder in Down's syndrome. 296 22

A case of a child with trisomy 21 and acute megakaryoblastic leukemia (AMBL) is reported. Histological examination of the bone marrow showed progressive fibrosis and replacement with megakaryoblasts. The diagnosis was confirmed by platelet peroxidase reaction and immunofluorescent staining with anti-factor VIII. Serial cytogenetic studies using banding techniques at various stages during the course of the disease (preleukemia, leukemia, remission, and relapse) showed several chromosomal abnormalities (unbalanced translocation between chromosomes 1 and 4 leading to trisomy 1q, trisomy 7q, monosomy 7p, and a reciprocal translocation between chromosomes 10 and 16). AMBL in childhood is probably more common than previously reported. Any association between AMBL and a particular cytogenetic abnormality must await further cytogenetic studies, specifically those employing banding techniques.
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PMID:Acute megakaryoblastic leukemia in Down's syndrome: report of a case and review of cytogenetic findings. 315 53

A 74-year-old Japanese male with a 4-year history of refractory anemia with excess of blasts is reported here. Chromosome study revealed the bone marrow cells of this patient to contain a t(3;4)(q26;q21). Ultrastructural analysis of platelet peroxidase and immunocytochemical study using monoclonal antibody for platelet antigen revealed a large number of blasts in the bone marrow to be megakaryoblasts. Thus, this case was thought to be one of a myelodysplastic syndrome with excess of blasts including megakaryoblastic proliferation showing chromosome changes at 3q26 and 4q21. The relationship of the anomaly on the long arm of a chromosome #3, especially at band 3q26, to abnormal megakaryoblastic proliferation is discussed.
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PMID:Translocation t(3;4)(q26;q21) in myelodysplastic syndrome with megakaryoblastic proliferation. 339 94

We have tried to improve existing methods for demonstration of platelet peroxidase (PPO) in human platelets and megakaryocytes by introducing a fixation of 0.1% glutaraldehyde prior to incubation in the DAB medium. This prefixation with low concentration of glutaraldehyde preserves excellent morphological detail and does not inhibit PPO activity. All 23 platelet-rich plasma samples show PPO reaction product in the dense tubular system after incubation in DAB medium with 0.003% H2O2. When 0.01% H2O2 is used in excessive DAB medium, PPO activity can also be demonstrated in platelets and megakaryocytes of bone-marrow cell suspensions. This method can be used for the identification of megakaryoblasts in acute non-lymphocytic leukemia, myelodysplastic syndromes and in blastic crisis of chronic myeloid leukemia. PPO cytochemistry can be combined with postfixation in a OsO4-ruthenium red mixture. This method reveals alpha-granules, dense bodies, microtubuli, glycogen, mitochondria, dense tubular system and invaginated membrane system in the same platelet and is useful for investigation of platelet ultrastructure.
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PMID:A reliable method with good cell preservation for the demonstration of peroxidase activity in human platelets and megakaryocytes. 619 33

Morphological and functional abnormalities of the megakaryocytic series have been well described in myelodysplastic syndromes. Platelet peroxidase has always been demonstrated in abnormal megakaryocytes and early megakaryoblasts in such syndromes. We have studied a case of myelodysplastic syndrome with marked morphological abnormalities of megakaryocytes in which ultrastructural studies showed the coexistence of platelet peroxidase positive and platelet peroxidase negative megakaryocytes. This enzymatic deficiency was confirmed by the ultrastructural study of circulating platelets. This case appears to be the first report of a partial platelet peroxidase deficiency. It adds to the enzymatic abnormalities in myelodysplastic syndrome already described for the red cells and the granulocytic cells.
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PMID:Platelet peroxidase deficiency in a case of myelodysplastic syndrome with myelofibrosis. 663 May 73

We describe a 68-year-old Japanese male with hypoplastic acute myelogenous leukemia (AML) who achieved complete hematological reconstitution following granulocyte colony-stimulating factor (G-CSF) administration. The patient had pancytopenia and the bone marrow was hypocellular with 19 to 36% peroxidase-positive blasts without morphological abnormalities suggestive of myelodysplasia. After receiving G-CSF as a supportive therapy for pneumonia, the blood count became normal and the bone marrow was normocellular with less than 5% of blasts. Without subsequent chemotherapy, he relapsed as a form of overt leukemia and died of pneumonia. Chemotherapy may be necessary to maintain remission in hypoplastic AML after hematopoietic reconstitution by G-CSF.
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PMID:Successful hematopoietic reconstitution with granulocyte colony-stimulating factor in a patient with hypoplastic acute myelogenous leukemia. 749 88


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