title: Aplastic anemia and monosomy 7-associated dysmegakaryocytopoiesis.
abstract: Aplastic anemia (AA) is marrow failure due to an inadequate number of hematopoietic cells in the marrow. Prior reports have described a more aggressive clinical course in aplastic anemia with monosomy 7. We report 3 pediatric cases of AA with normal cytogenetics followed by acquisition of monosomy 7. Bone marrow biopsies were initially diagnostic of AA but later showed monosomy 7 and an increased number of megakaryocytes with small hypolobated nuclei. Immunohistochemical stains for CD61 highlighted the marked dysmegakaryocytopoiesis. The marrow blast percentage was increased in only 1 patient with 4.6% blasts. The 3 patients underwent bone marrow transplantation, and each has remained disease free for 7 to 18 months after transplantation. Pediatric patients with AA and normal cytogenetics may develop monosomy 7 with a myelodysplastic syndrome, unclassified. Patients with AA and monosomy 7 should be evaluated for dysmegakaryocytopoiesis.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota, Medical School, Minneapolis 55455, USA.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Dolan
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Singleton
authors.forename: Joseph
authors.initials: J
authors.lastname: Neglia
authors.forename: Adina
authors.initials: A
authors.lastname: Cioc
mesh_terms: D000293:Adolescent; D000741:Anemia, Aplastic / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D001853:Bone Marrow / Q000473:pathology*; D016026:Bone Marrow Transplantation; D002648:Child; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008533:Megakaryocytes / Q000473:pathology*; D009006:Monosomy / Q000235:genetics*; D009190:Myelodysplastic Syndromes / Q000235:genetics / Q000276:immunology / Q000473:pathology*
chemical_list: D007166:Immunosuppressive Agents