1/13. Corneal myxoma associated with keratoconus and Down's syndrome.PURPOSE: Primary myxoma of the cornea is extremely rare. Until now, only four primary corneal myxomas were reported in the literature, whereas secondary involvement of the cornea by conjunctival and limbal tumors is much more common. methods: We report an additional case in a 26-year-old woman with keratoconus and Down's syndrome. Excision of the corneal mass was performed by penetrating keratoplasty. Histochemical, immunohistochemistry, and ultrastructural studies were used to obtain a definitive diagnosis. RESULTS: The tumor exhibited the characteristic histologic features of myxoma. The tumor cells showed immunoreactivity for vimentin but not for S-100 protein, epithelial membrane antigen, CAM 5.2, HHF-35, or muscle-specific actin. Ultrastructural features were fibroblast-like or stellate cells with cytoplasm containing abundant, rough reticulum and dilated cisternae. No recurrence was observed 36 months after penetrating keratoplasty. CONCLUSION: This is only the fifth report of such an occurrence. Although the coexistence of myxoma in Down's syndrome with keratoconus is described here for the first time, the differential diagnosis of apparently evident acute hydrops on clinical inspection should not rule out the possibility of a corneal myxoma. Histologic analysis should therefore be performed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/13. Transient myeloproliferative disorder with erythroid differentiation in down syndrome.A newborn with a karyotype of 47, XY, 21 presented at birth with a white blood cell count of 27 700/microL of which 61% were blast cells. The blast cell morphologic structure was initially not characteristic of any particular lineage, although the cytoplasm contained fine granules and occasional small vacuoles. Routine cytochemical stains were negative, except one for nonspecific esterase that was faintly positive in most of the blast cells. Flow cytometric analyses showed that the blast cells expressed glycophorin A with a subset dimly coexpressing CD45 and were negative for CD34, CD71, myeloid, lymphoid, and platelet-associated antigens. These immunophenotypic findings were consistent with an abnormal erythroid phenotype. A few days postpartum, markedly dysplastic erythroid precursor cells appeared in the peripheral blood and increased in number as the early blast cells decreased. After a period of subdued blast cell production, a second wave of increase in the number of blast cells and dysplastic erythroblasts followed and ended with the disappearance of circulating abnormal cells. The child is now 5 years old and no major illness has been reported since the remission of this disorder. This case most likely belongs to the category of transient myeloproliferative disorders, although the erythroid-like phenotype of blast cells and the evidence of single-lineage maturation to circulating dysplastic erythroid precursors allow the suggestion that this process could represent a special form of a self-limited hematologic disorder in down syndrome.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/13. Down's syndrome and autoimmunity.A patient with Down's syndrome (DS) with multiple autoimmune phenomena is described. She suffered from hypothroidism, a celiac-like enteropathy and hemolytic anemia, and displayed cellular immunity directed against peripheral nerve antigen and basic myeloprotein and serum autoantibodies to many other tissue antigens. Her mother did not suffer from any overt autoimmune disease, but similar autoantibodies were found in her serum. It is suggested that DS resembles other autoimmune diseases, especially that which occurs in the NZB mice. The resemblance is based on the assumption that in both cases genetic and/or viral factors cause T-cell dysfunction which leads on the one hand to increased susceptibility to infections and leukemias, to autoimmune phenomena and to depressed cellular immunity, and on the other hand to increased B--cell reactivity.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
4/13. interphase cytogenetic analysis of clonality in peripheral blood cells from a patient with down syndrome and acute megakaryoblastic leukemia.A combination of fluorescence-activated cell sorting and interphase fluorescence in situ hybridization (FISH) techniques was used to detect a clonal chromosomal marker in blasts, granulocytes, and T and B lymphocytes of the peripheral blood from a patient with down syndrome and acute megakaryoblastic leukemia (AMKL) associated with trisomy 8 as a karyotypic abnormality. Immunophenotypic studies with flow cytometry showed two populations of leukemic blasts distinguished by their expression of the CD34 antigen. interphase FISH studies revealed clonal trisomy 8 FISH signals in almost all blast cells, regardless of CD34 expression, as well as in a small subpopulation of granulocytes. Normal chromosome 8 signal patterns were detected in T and B cells and in a great majority of granulocytes. The present study provides evidence for the clonal involvement of leukemic blasts in AMKL of down syndrome, indicating that a trisomy 8 abnormality may be a primary event in leukemogenesis. The transformation occurs in progenitor cells with limited myeloid differentiation and without involvement of lymphoid lineage cells.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/13. down syndrome in two of three triplets.This is the first report to our knowledge of trisomy 21 in two members of a set of triplets. The two with down syndrome are monozygous; the other triplet is not identical. These triplets were born to a 22-year-old woman in whose family there have been six sets of twins (four like-sex) since 1775. Neither parent has any chromosomal abnormality. Zygosity estimates in the triplets are derived from studies of red blood cell antigens and HLA typing. Twinning has been reported in association with many different chromosome abnormalities. It has been suggested that the incidence of down syndrome among twins is significantly higher than among singletons. It seems likely that some families have a heritable predisposition to both twinning and chromosome abnormalities.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/13. down syndrome with myelodysplasia of megakaryoblastic lineage.The association between down syndrome and acute myelogenous leukemia (AML) has been well documented. AML in down syndrome is usually a specific type of megakaryoblastic leukemia (M7, AMKL). A myelodysplastic syndrome generally precedes this malignancy. down syndrome patients with AMKL have a much better prognosis than other children with AML. A case study of a 22-month-old female with down syndrome and myelodysplastic syndrome of a megakaryoblastic lineage is presented here. Upon admission to a pediatric hematology/oncology clinic, flow cytometry results reported a distinct population of phenotypically abnormal myeloblasts expressing myeloid antigens and the immature cell markers. The patient was placed on a national research group study and began chemotherapy treatment. To date she has received two courses of cytarabine (ara-c) and daunorubicin therapy, which were tolerated well, and is awaiting her third course. Her blood counts stabilize for a while after treatments and her prognosis is good.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/13. Reversible increase in serum alpha-fetoprotein content associated with hepatic dysfunction during chemotherapy for seminoma.Serial monitoring of the serum content of the beta subunit of human chorionic gonadotropin (beta hCG) and alpha-fetoprotein (alpha FP) is useful in the initial staging of germ cell tumors and assessing the response to treatment. An increase in either marker during or following treatment almost always heralds disease progression and indicates the need for additional therapy. We report two patients in whom substantial increases in the serum content of AFP occurred during chemotherapy for advanced seminoma. Hepatic dysfunction was present in both patients; in one patient, a chronic carrier of hepatitis b virus, the liver dysfunction was associated with reactivation of hepatitis B manifested by anicteric hepatitis and hepatitis B e antigen positivity. Marked tumor regression had occurred in both patients, and chemotherapy was discontinued in spite of the elevated alpha FP level. The alpha FP content in the serum gradually returned to normal, and hepatic dysfunction resolved. Both patients remain free of disease 15 and 17 months following the last chemotherapy treatment. These cases illustrate that hepatic dysfunction and alpha FP production may occur during chemotherapy and that increases in serum alpha FP content must be interpreted with caution since the elevated alpha FP level does not always indicate progression of germ cell tumors.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/13. Pseudoleukemia in Down's syndrome. Analysis of immunophenotype and gene rearrangement.This report demonstrates a case of transient abnormal myelopoiesis (TAM) evolving in a patient with Down's syndrome. A diagnosis was established after the patient's blast cell count decreased considerably three weeks after the initial leukemic phase. The blast population in the authors' case expressed Leu-9 (CD7), 6D1, and TdT . Cytochemistries showed some of the blast population to be peroxidase positive and sudan black positive. Platelet peroxidase by electron microscopic examination showed some positive blasts. Therefore, surface markers and cytochemical studies in this case suggested an abnormal proliferation involving a pluripotential stem cell capable of expressing myeloid and lymphoid characteristics. cytogenetics was performed at birth and showed 47,XY, 21/48,XY, 21, mar, confirming the diagnosis of Down's syndrome. The origin of the chromosomal fragment was uncertain. It was of interest that during the remission phase of his pseudoleukemia there was a concomitant decrease in the extra chromosomal fragment. Immunoglobulin and T-cell antigen receptor gene rearrangement studies showed only germline patterns, indicating that the lymphoid cells in the blast population were not clonally expanded. Therefore, immunoglobulin and T-cell antigen receptor rearrangement analysis and immunophenotyping are extremely valuable techniques in distinguishing between TAM and acute lymphoblastic leukemia in patients with Down's syndrome.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
9/13. Acute leukemia of megakaryocyte lineage with tumor formation. An autopsy case of patient with Down's syndrome.In this report we present the autopsy findings of acute megakaryoblastic leukemia with tumor formation in a 2-year-old female infant with Down's syndrome. Chromosomal analysis of blast cells revealed constitutional anomaly of trisomy 21 and two other related types of abnormal clones. Flow cytometric examination revealed blast cells expressing Ia-like or hla-dr antigens. Postmortem examination showed extensive infiltration of leukemic cells in most of the examined organs, including the bone marrow with myelofibrosis. Tumor masses in the maxillary, frontal and femoral bones and the atria of the heart had undergone massive infiltration of atypical blast cells with an increase in the reticulin network. The final diagnosis was confirmed by ultrastructural cytochemistry of the platelet peroxidase reaction as well as by immunological staining utilizing anti-platelet glycoprotein IIb/IIIa, antiplatelet factor 4 and anti-beta-thromboglobulin antibodies for the blast cells. It seems likely that platelet-derived growth factor, secondary to an increase in the reticulin network, plays a major role in myelofibrosis of acute megakaryoblastic leukemia with tumor formation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/13. Pediatric legionnaires' disease: diagnosis by direct immunofluorescent staining of sputum.legionnaires' disease occurred in a 3-year-old boy with Down's syndrome. His illness was characterized by bilateral pneumonia, high fever, and response to erythromycin. The diagnosis was made by demonstrating legionella pneumophila, serogroup 1, in sputum with a direct fluorescent antibody stain. L pneumophila antigen was detected in urine by an enzyme-linked immunospecific assay. The diagnosis was confirmed by a more than fourfold rise in serum antibody titer. Although legionnaires' disease appears to be uncommon in children, it should be included in the differential diagnosis of pneumonia in the immunocompromised child.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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