Granulocyte, monocyte and blast immunophenotype abnormalities in acute myeloid leukemia with myelodysplasia-related changes.

Little literature exists regarding granulocyte and monocyte immunophenotype abnormalities in Acute Myeloid Leukemia (AML). We hypothesized that granulocyte and monocyte immunophenotype abnormalities are common in AML, and especially in AML with myelodysplasia-related changes (AMLMRC). Bone marrow or peripheral blood specimens from 48 cases of AML and 22 cases of control specimens were analyzed by flow cytometric immunophenotyping.

Atypical angioimmunoblastic T-cell lymphomas masquerading as systemic polyclonal B-immunoblastic proliferation.

Angioimmunoblastic T cell lymphoma (AITL) is a relatively rare peripheral T cell lymphoma derived from follicular T helper cells. AITL has a varied presentation, both clinically and morphologically. AITL can pose a diagnostic challenge as it may be difficult to identify and characterize the neoplastic cells among the polymorphous infiltrates composed of polyclonal B immunoblasts and plasma cells.

Sensitivity and specificity of bone marrow hemophagocytosis in hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal disease characterized by abnormal activation of T-lymphocytes and macrophages. The diagnosis of HLH can be established if there is a family history of HLH, or evidence of genetic defects, or if 5 of 8 clinicopathologic criteria are fulfilled. This case-control study aimed to examine the extent of hemophagocytosis on the bone marrow examination of patients fulfilling diagnostic criteria for HLH.

Recognition of Naegleriae ameba surface protein epitopes by anti-human CD45 antibodies.

Phagocytosis is a highly conserved mechanism exhibited by both free-living amebas and mammalian blood cells. Similarities demonstrated by either cell type during engulfment of the same bacterial species may imply analogous surface proteins involved in receptor-mediated endocytosis. The increased availability of anti-human leukocyte antibodies or clusters of differentiation (CD) markers used in conjunction with flow cytometric (FCM) and/or immunohistochemical (IHC) analysis provides investigators with a relatively easy method to screen different cell populations for comparable plasma membrane proteins.

Acute megakaryoblastic leukemia after transient myeloproliferative disorder with clonal karyotype evolution in a phenotypically normal neonate.

We report a case of transient myeloproliferative disorder (TMD) in a neonate without features of Down syndrome (DS) with clonal karyotype evolution, after apparent spontaneous resolution of TMD, but eventually progressing to acute megakaryoblastic leukemia (AMKL). The patient had petechiae, thrombocytopenia, and blastemia. Trisomy 21 with a satellited Y chromosome (Yqs) was found in proliferating blasts.

Extranodal posttransplant plasmacytic hyperplasia with subsequent posttransplant plasmacytic malignancy: six-year interval case report and review of the literature.

Posttransplant lymphoproliferative disorders (PTLDs) represent a morphologic, immunophenotypic, and genotypic spectrum of disease. Most recently, Knowles et al divided PTLDs into 3 distinct categories: (1) plasmacytic hyperplasia, (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma, and (3) immunoblastic lymphoma and multiple myeloma. Although one form of PTLD may progress to another form, only 1 previous case has been reported in which multiple myeloma developed 14 months after an original diagnosis of plasmacytic hyperplasia.