首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 890 毫秒
1.
Transient myeloproliferative disorder is a condition clinically resembling congenital acute myelogenous leukemia. As in acute leukemias the blast cell population in this disorder may have either normal or abnormal chromosomal complement. Transient myeloproliferative disorder is well recognized in neonates with a complete or mosaic trisomy 21 (Down's syndrome). We report a phenotypically and cytogenetically normal infant with this syndrome in whom only blast cells showed trisomy 21. We postulate that the pathogenesis of the transient myeloproliferative disorder in both Down's syndrome infants and those with a normal chromosomal complement is related to abnormal prenatal production of placental regulatory hemopoietic factors caused by chromosomal defect(s) confined to placental tissues.  相似文献   

2.
We have studied six cases presenting as myeloproliferative disease with myelofibrosis in children and compared our findings with those of other investigators. Besides the classic chronic juvenile or adult type of leukemia, two groups of myeloproliferative syndrome are most often seen in pediatric practice: (1) myeloproliferative disease associated with monosomy C, which has clear-cut clinical features and a poor prognosis, with bone marrow grafting the only potentially successful treatment at this time; and, (2) idiopathic myelofibrosis with normal karyotype, which occurs less frequently and seems to have less distinct boundaries. We conclude that determination of karyotype is mandatory in these syndromes.  相似文献   

3.
Transient myeloproliferative disorder (TMD) is a leukemia type that occurs typically in newborns. In Down syndrome, TMD is referred to as transient abnormal myelopoiesis (TAM).32 Recently, transientness has also been reported in acute myeloid leukemia patients with germline trisomy 21 mosaicism, and even in cases with somatic trisomy 21, with or without GATA1 mutations. TMD cases without trisomy 21 are rare, and recurrent genetic aberrations that aid in clinical decision‐making are scarcely described. We describe here a TMD patient without trisomy 21 or GATA1 mutation in whom single‐nucleotide polymorphism analysis of leukemic blasts revealed a novel combined submicroscopic deletion (5q31.1–5q31.3 and 8q23.2q24).  相似文献   

4.
A 22-week-old fetus with trisomy 21 demonstrated intratubular germ cell neoplasia. This is the second report of in situ testicular neoplasia in a fetus with trisomy 21, suggesting that the mechanism responsible for the possible excess of testicular germ cell tumors that occur in Down syndrome is operative in early fetal life. Because no examples of neonatal testicular germ cell tumor in trisomy 21 have been reported, we suggest that this in situ neoplasm may disappear during gestation, such as the trisomy 21-associated transient myeloproliferative syndrome does shortly after birth. This disappearance may be due to a controlled regression phenomenon.  相似文献   

5.
The cellular events that lead to transient myeloproliferative syndrome (TMS) in patients with trisomy 21 mosaicism confined to the hematopoietic system are poorly understood. The authors attempt to define the event that led to the development of TMS in a single patient with clonal trisomy 21. A phenotypically normal neonate with clonal trisomy 21 is described. At the time when his TMS was resolving, fluorescent in situ hybridization analysis was performed on cell populations sorted by flow cytometry to determine what cell populations contained trisomic cells. Trisomy 21 was found in cells of the erythrocytic and monocytic lineages, but not in the stem cells, progenitor compartment, megakaryocytes, lymphocytes, or neutrophils. These results support the hypothesis that, in this neonate, trisomy 21 occurred in a multipotent hematopoietic progenitor, and a subsequent event led to the appearance of the blast population.  相似文献   

6.
Transient myeloproliferative disorder (TMD) is an uncommon syndrome strongly associated with abnormalities of chromosome 21. Blast transient proliferation appears most frequently at neonatal age and usually resolves spontaneously in two or three months. Two patients, a girl and a boy, with neonatal onset of TMD are reported. They both presented trisomy 21 mosaicism according to bone marrow cytogenetic analysis. Patient 1, on one end of the spectrum, showed a “classic” benign course with rapid resolution and favorable outcome. Patient 2, on the other hand, had two blast outbursts both followed by spontaneous remissions. He failed to thrive and never reached a good general condition, dying at 5 months of age from a respiratory infectious complication. The necropsy showed generalized extramedullary hemopoiesis without evidence of bone marrow blast infiltration or myelofibrosis. TMD has some clinical and laboratory features that make it unique and distinguishable from true congenital leukemia with which it may be initially mistaken. It usually has a benign course followed by a favorable outcome. As trisomy 21 mosaicism may not have overt phenotypic stigmata, it is possible that many cases of TMD in these children may have a silent, non-detected course. We also conclude that a favorable outcome is not always to be expected in TMD. © 1995 Wiley-Liss, Inc.  相似文献   

7.
Idiopathic myelofibrosis with generalized periostitis in a 4-year-old girl   总被引:1,自引:0,他引:1  
Idiopathic myelofibrosis, a chronic myeloproliferative disorder of unknown origin, is characterized by splenomegaly, extramedullary hematopoiesis, leukoerythroblastosis, teardrop erythrocytes, and myelofibrosis. It is a rare disorder in childhood. The authors describe a 4-year-old girl with features consistent with idiopathic myelofibrosis, who also had generalized solid laminated periosteal reaction involving all long bones. The presence of thrombocytopenia at the onset and lack of leukocytosis were in contrast to the reported features seen in children. Recent case reports describe a relatively indolent course in children. Spontaneous remissions have also been described in pediatric cases. The fulminant course of this patient without any features of malignant transformation was noteworthy in this regard.  相似文献   

8.
Patients with trisomy 21 have an increased incidence of haematological disorders, including neonatal 'leukaemoid reaction'(transient myeloproliferative disorder [TMD]) and acute leukaemias. In the past it has been felt that patients with trisomy 21 and acute leukaemia do not tolerate, and hence may not warrant, therapy as intensive as those without the syndrome. The present authors' experience and the current literature do not support this view. Two cases are reported of acute myeloid leukaemia in children with trisomy 21, successfully treated with intensive chemotherapy and bone marrow transplantation.  相似文献   

9.
Transient myeloproliferative disorder is a form of self-limited leukemia that occurs almost exclusively in neonates with Down syndrome. The authors report an unusual case of a newborn without constitutional trisomy 21 who developed undifferentiated leukemia and subsequently achieved clinical and molecular remission without chemotherapy. Cytogenetics and molecular analysis have shown trisomy 21 and GATA1 mutation restricted to leukemic cells. G-to-T transversion was detected, which is predicted to result in a premature stop codon (c.119G>T; pGlu67X) in diagnosis samples. These findings emphasize that there must be a powerful interaction between GATA1 and trisomy 21 in leukemogenesis process.  相似文献   

10.
Not only in newborns with Down syndrome, but newborns without phenotypic features of Down syndrome also develop transient myeloproliferative disorder (TMD). In these cases, trisomy 21 and related chromosomal abnormalities are either constitutionally mosaic or limited to blood cells. Risk factors for early death of these patients are unknown so far. We here report a fatal case of TMD without phenotypic features of Down syndrome and review literature to identify risk factors associated with early death. Not only are gestational age and white blood cell count risk factors for early death in TMD with Down syndrome, but they also appear to be risk factors in TMD without Down syndrome.  相似文献   

11.
An infant with Down syndrome (DS) and RH isoimmunization developed transient myeloproliferative disorder (TMD) during the neonatal period. At 16 months she presented with acute nonlymphocytic leukemia (ANLL). Cytogenetic studies during TMD showed trisomy 21 only but new abnormalities emerged during ANLL. She is now in complete remission 5 years after diagnosis. Patients with TMD have either trisomy 21 or mosaic 21 in blood and bone marrow but in phenotypically normal children this cell line disappears with resolution of the TMD. A review of the literature indicates that there are no clinical, hematological, or cytogenetic differences between DS children with TMD who subsequently develop acute leukemia and those who do not. However, the leukemia in the former group may differ in presentation, type, and possibly survival time from other DS children who develop leukemia de novo.  相似文献   

12.
We describe a 17-year-old boy with aplastic anemia who had Sweet syndrome develop with increasing expansion of trisomy 8. The diagnosis of aplastic anemia was made at 6 years of age. Cytopenias partially responded to danazol therapy. Cytogenetic studies of bone marrow (BM) cells were normal until the detection of trisomy 8 at 14 years of age. This clone increased with the progression of cytopenias. Cell sorting and fluorescence in situ hybridization analysis revealed that trisomy 8 was present only in nonlymphoid elements. When the patient was 17 years of age, Sweet syndrome developed. BM study showed myelodysplastic features, in which trisomy 8 occupied 74% of BM cells with additional chromosomal changes. Trisomy 8 may contribute to the late transformation of myeloid lineages in BM failure.  相似文献   

13.
14.
15.
A total of 239 cases of Down syndrome (DS) were seen in the genetic clinic between 1992 and 2003, of which of 15 had hematological manifestations at presentation. These comprised 4 cases of transient myeloproliferative disorder (TMD), 3 cases of TMD/acute leukemia, 4 cases of acute leukemia (AL), 2 of dual deficiency anemia, and 1 case each of myelofibrosis and idiopathic thrombocytopenia. This study emphasizes the fact that an abnormal hemogram in a DS patient does not necessarily indicate AL/TMD, as a considerable number of the cases in this study had other hematological abnormalities. TMD can be differentiated from acute leukemia only on follow-up.  相似文献   

16.
Myelofibrosis with myeloid metaplasia is defined as a myeloproliferative disorder characterized by leukoerythroblastosis, tear drop erythrocytes, extramedullary hematopoesis and varying degree of myelofibrosis. It may be idiopathic or secondary to a large number of conditions. Here is a rare case of myelofibrosis occurring in a patient with juvenile rheumatoid arthritis.  相似文献   

17.
A total of 239 cases of Down syndrome (DS) were seen in the genetic clinic between 1992 and 2003, of which of 15 had hematological manifestations at presentation. These comprised 4 cases of transient myeloproliferative disorder (TMD), 3 cases of TMD/acute leukemia, 4 cases of acute leukemia (AL), 2 of dual deficiency anemia, and 1 case each of myelofibrosis and idiopathic thrombocytopenia. This study emphasizes the fact that an abnormal hemogram in a DS patient does not necessarily indicate AL/TMD, as a considerable number of the cases in this study had other hematological abnormalities. TMD can be differentiated from acute leukemia only on follow-up.  相似文献   

18.
The clinical, hematologic, and cytogenetic findings are described in a patient who developed clinical and hematologic features of acute myelogenous leukemia (AML) after a three-year period of observation with unexplained thrombocytopenia. Five months before the diagnosis of AML she developed hepatosplenomegaly and a lupus-like syndrome. At this time she was also found to have trisomy 21 in all bone marrow cells studied, in addition to trisomy 8 in a few cells. The finding of trisomy 21 in all of the bone marrow cells examined could reflect a nonrandom alteration in the leukemic stem line or it might indicate that mosaic patients with trisomy 21 cells in their bone marrow share the increased risk of AML that has been documented for trisomy 21 patients.  相似文献   

19.
The development of myeloid leukemias and myelodysplastic syndrome (MDS) is common in children with trisomy 8 mosaicism. However, the mechanisms by which the presence of an additional chromosome 8 translates to an increased risk of leukemias and MDS is currently unknown. The authors describe the analysis of stromal cells from a pediatric MDS patient with constitutional trisomy 8. Patient and control marrow stromal cells were analyzed for alterations in cytokine production. Clonogenic assays were used to examine stromal support for hematopoiesis. The interplay between leukemia cells and stroma was studied by co-culture experiments. The results indicate that stromal cell function in this patient was seriously altered in favor of progenitor cell proliferation and expansion. This indicates that constitutional trisomy 8 in stromal cells plays a critical role in the pathogenesis of MDS.  相似文献   

20.
The development of myeloid leukemias and myelodysplastic syndrome (MDS) is common in children with trisomy 8 mosaicism. However, the mechanisms by which the presence of an additional chromosome 8 translates to an increased risk of leukemias and MDS is currently unknown. The authors describe the analysis of stromal cells from a pediatric MDS patient with constitutional trisomy 8. Patient and control marrow stromal cells were analyzed for alterations in cytokine production. Clonogenic assays were used to examine stromal support for hematopoiesis. The interplay between leukemia cells and stroma was studied by co-culture experiments. The results indicate that stromal cell function in this patient was seriously altered in favor of progenitor cell proliferation and expansion. This indicates that constitutional trisomy 8 in stromal cells plays a critical role in the pathogenesis of MDS.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号