Two cases of transfusion-transmitted Anaplasma phagocytophilum.

Anaplasma phagocytophilum, the causative agent of human granulocytic anaplasmosis, is an obligate intracellular bacterium most commonly acquired from tick bites. High seroprevalence rates in endemic regions suggest that transfusion transmission of A phagocytophilum would be a common event; however, only 2 cases have previously been reported. The exact cause of this discrepancy is not known.

Gamma heavy-chain disease: defining the spectrum of associated lymphoproliferative disorders through analysis of 13 cases.

Gamma heavy-chain disease (gHCD) is defined as a lymphoplasmacytic neoplasm that produces an abnormally truncated immunoglobulin gamma heavy-chain protein that lacks associated light chains. There is scant information in the literature regarding the morphologic findings in this rare disorder, but cases have often been reported to resemble lymphoplasmacytic lymphoma (LPL). To clarify the spectrum of lymphoproliferative disorders that may be associated with gHCD, this study reports the clinical, morphologic, and phenotypic findings in 13 cases of gHCD involving lymph nodes (n=7), spleen (n=2), bone marrow (n=8), or other extranodal tissue biopsies (n=3).

Bone marrow stromal cells from myeloma patients support the growth of myeloma stem cells.

It has been well documented that bone marrow stromal cells (BMSCs) of multiple myeloma patients play a pivotal role in supporting the growth of mature myeloma cells. With evolving concepts concerning the presence of myeloma stem (initiating) cells, we aimed this investigation to specifically address the supportive role of BMSCs for myeloma stem cell growth in vitro and in vivo. BMSC lines were derived from myeloma or control patients (myeloma or control BMSCs).

Laboratory findings in CD4(+) large granular lymphocytoses.

Large granular lymphocytic (LGL) leukemia is an uncommon disorder of mature T or natural killer (NK) cells. Most T-LGL proliferations are CD3(+)/CD8(+), although rare CD4(+) clonal T-LGL expansions have been reported. We report the clinicopathologic features of eight patients with aberrant CD4(+), cytotoxic T-cell lymphocytoses.