摘要:

Purpose: To study the platelets from a family with a new form of inherited giant platelet disorder.Patients and Methods: Two siblings exhibited a hemorrhagic disorder characterized by moderate thrombocytopenia, giant platelets, and markedly prolonged bleeding time. The parents had no discernible platelet defect. Both children also developed mitral regurgitation requiring medication, and one underwent surgical replacement at the age of 3 years.Results: The mean platelet size was greater than 20 μm3. Direct measurements of the two major axes of each of 12 platelets on electron micrographs revealed a range of 2×4 to 4×6 μm. Electron microscopy did not demonstrate any abnormality of granule content. The platelets agglutinated normally with ristocetin and aggregated normally with collagen. However, the aggregation was slightly slower than normal with ADP, epinephrine, and Na arachidonate. Two-dimensional unreduced versus reduced SDS-polyacrylamide gel electrophoresis of surface radioiodinated platelet glycoproteins revealed absence of proteins Ia, Ic, and IIa in both affected children, whereas GP Ib, IIb, and IIa appeared normal. The 2D gels of platelet glycoproteins from both parents were identical to controls. Western blots demonstrated that GP Ic, Ic', Ib, and Ia/IIa were present.Conclusions: This disorder represents a new syndrome of thrombocytopenia with giant platelets distinct from Bernard-Soulier, Montreal giant platelets, Swiss cheese platelets, May-Hegglin anomaly, and other previously described syndromes.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: The pathogenesis of thrombocytopenia in patients with thrombocytopenia with absent radii (TAR) syndrome has not been clarified yet.Patients and Methods: This is the first report of a Japanese patient with TAR syndrome. We studied his megakaryopoiesis in vitro and serum levels of thrombopoietin (TPO).Results: Serum levels of TPO in the patient with TAR syndrome were comparable with those of an age-matched control. The bone marrow cells from the patient with TAR syndrome actually generated megakaryocyte colonies in the presence of TPO and the numbers were significantly greater than those from the age-matched control marrow. However, megakaryocyte colonies from the marrow cells with TAR syndrome contained a much lower number of cells per colony and the size of the individual megakaryocytes appeared to be smaller.Conclusion: These data suggest that megakaryocyte progenitors from patients with TAR syndrome may have decreased proliferative and differentiative capacity to respond to TPO, leading to thrombocytopenia.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: We report a case of an isolated optic nerve relapse 3.5 years after diagnosis of hyperdiploid acute lymphoblastic leukemia (ALL) in a 6-year-old boy who had been off treatment for 3 months. The use of interphase fluorescence in situ hybridization (FISH) for clonal identification of chromosome abnormalities is described.Patient and Methods: An asymptomatic lesion over the right optic nerve head was identified on routine funduscopic exam. Fine needle aspiration of the optic nerve infiltrate provided tissue for morphologic, immunohistochemical, and FISH analyses.Results: FISH showed similar but not identical chromosome makeup of the leukemic blasts at the time of relapse as compared to tissue samples obtained at the time of diagnosis.Conclusion: Despite antimetabolite therapy, hyperdiploid ALL can rarely recur isolated to an optic nerve. FISH is a useful adjunct for confirming relapse when low numbers of white blood cells are obtained with fine needle aspiration.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: To describe a case of severe diarrhea caused by Cryptosporidium in a patient undergoing maintenance chemotherapy. Important aspects of disease caused by Cryptosporidium, including diagnosis and treatment, are also reviewed.Methods and Results: A 4-year-old boy with acute lymphoblastic anemia in remission had a prolonged course of diarrhea and wasting. C parvum was identified in the gastrointestinal tract by biopsy and in the stool using modified acid fast staining. Improvement in the stool consistency was noted after 3 days of therapy with azithromycin, and, after 14 days of therapy, Cryptosporidium oocysts could no longer be identified in the stool.Conclusions: C parvum should be considered in all immuno-compromised patients with severe or prolonged diarrhea, especially if there is no blood or leukocytes in the stool. Because Cryptosporidium is not always tested for in a routine ova and parasite examination, the lab should be notified if it is in the differential diagnosis. Azithromycin therapy may prove beneficial in the treatment of intestinal Cryptosporidium in immunocom-promised individuals.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: To describe a patient with a variant translocation (1;13)(p36;q14) in an alveolar rhabdomyosarcoma and compare the clinical course with four other cases.Patients and Methods: A 10-year-old girl presented with multiple masses involving the thigh, abdomen, chest wall, and scalp with pleural effusion and edema of the lower extremities.Results: A bone marrow biopsy, aspirate, and biopsy of the thigh mass all showed tumor invasion. Histopathology and cytogenetics of the thigh mass revealed an alveolar rhabdomysarcoma with a t(l;13)(p36q14) variant. There was no response to aggressive therapy and the patient died within 3 weeks of admission.Conclusion: Variant t(l;13)(p36;q14) has now been described in 5 cases of rhabdomyosarcoma. and may define a subset of patients with extensive disease at diagnosis unresponsive to current therapeutic modalities.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: We describe the spontaneous resolution of a myelodysplastic cytogenetic abnormality developing during the treatment of acute lymphocytic leukemia.Patients and Methods: A 6-year-old girl with acute lymphocytic leukemia had a clinical picture of myelodysplasia 18 months after diagnosis. The clonal cytogenetic abnormality, 46, XX, del(5)(q12q12), resolved spontaneously 4 months after the discontinuation of chemotherapy. Maintenance chemotherapy was resumed 1 month later and continued for an additional 9 months. Currently, she has been off therapy for 10 months.Conclusion: A myelodysplastic clonal cytogenetic abnormality developing during treatment may cause some confusion for management. This study demonstrates that spontaneous resolution is possible and that bone marrow transplantation or other intensive treatment may not be necessary.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Purpose: The clinical implications of many cytogenetic abnormalities in acute myeloid leukemia (AML) are now well established. However, questions about the significance of rarer abnormalities still exist, particularly in childhood disease.Patients and Methods: We report a case of a 91/2-year-old girl who had AML of the FAB M2 subtype. A diagnostic bone marrow aspirate and subsequent bone marrow aspirates were investigated using conventional cytogenetic methods.Results: Cytogenetic analysis of the diagnostic bone marrow aspirate showed a t(l l;20)(p15;q11.2) translocation as the sole acquired abnormality. After one course of chemotherapy, the patient achieved hematopoietic and cytogenetic remission which has been sustained for 1 year after presentation.Conclusion: This report demonstrates that rare non-random cytogenetic abnormalities are still to be described in AML, and that care should be taken when ascribing clinical significance to cytogenetic findings in childhood disease based on those of older patients.

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1077-4114    

出版商:OVID    

年代:1998

数据来源: OVID