A Randomized, Placebo-controlled Trial of Fidaxomicin for Prophylaxis of Clostridium difficile-associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation.

Background: Clostridium difficile-associated diarrhea (CDAD) is common during hematopoietic stem-cell transplantation (HSCT) and is associated with increased morbidity and mortality. We evaluated fidaxomicin for prevention of CDAD in HSCT patients.

Methods: In this double-blind study, subjects undergoing HSCT with fluoroquinolone prophylaxis stratified by transplant type (autologous/allogeneic) were randomized to once-daily oral fidaxomicin (200 mg) or a matching placebo.

Donor Lymphocyte Infusions Used to Treat Mixed-Chimeric and High-Risk Patient Populations in the Relapsed and Nonrelapsed Settings after Allogeneic Transplantation for Hematologic Malignancies Are Associated with High Five-Year Survival if Persistent Full Donor Chimerism Is Obtained or Maintained.

Mixed chimerism (MC), a persistent or increasing number of host cells after allogeneic hematopoietic stem cell transplantation (HSCT), is a predictor of disease relapse. Donor lymphocyte infusions (DLI) have the potential to enhance the graft-versus-malignancy (GVM) effect, reducing the risk of relapse in patients with MC. Hence, in addition to utilizing DLI in the relapsed setting, there is a motivation to pursue pre-emptive DLI for patients in complete remissions after HSCT.

Barriers to physician adherence to evidence-based monitoring guidelines in chronic myelogenous leukemia.

Purpose: Although monitoring of cytogenetic/molecular responses to therapy in chronic myelogenous leukemia (CML) facilitates superior outcomes, less than one half of CML patients are monitored using published evidence-based guidelines. Barriers to physician adherence with guidelines are unknown.

Methods: An anonymous survey was mailed to 515 hematologist-oncologists in New Jersey and Indiana exploring attitudes toward monitoring guidelines.

Transportation of peripheral blood progenitor cell products: effect of ambient temperature.

Background Aims: Peripheral blood progenitor cell (PBPC) products are often transported at high cell concentrations (>200 × 10⁹/L) over long distances, requiring >36 h transport time.

Methods: Fresh PBPC samples from eight healthy donors were studied with two viability assays for effects of temperature outside the transport container (ambient temperature). The Coleman 5272 container, routinely used by the National Marrow Donor Program (NMDP) with two -20°C gel packs, was compared with the Coleman 6216 container, which can hold four -20°C gel packs.

Transportation of peripheral blood progenitor cell products: effects of time, temperature and cell concentration.

Background Aims: Peripheral blood progenitor cell (PBPC) products are often transported at high cell concentrations (>200x10(9)/L) over long distances, requiring >36 h transport time.

Methods: Fresh PBPC samples from 12 healthy donors were studied with various viability assays regarding the effects of temperature, cell concentration and duration of storage.

Results: Trypan blue exclusion was far less sensitive to cell damage than two-color fluorescence for CD34 and 7-AAD, and colony-forming unit-granulocyte-macrophage (CFU-GM) assays; the latter assay proved the most sensitive.

Starting granulocyte-colony-stimulating factor (filgrastim) early after autologous peripheral blood progenitor cell transplantation leads to faster engraftment without increased resource utilization.

Background: Hematopoietic growth factor support is routinely used after autologous stem cell transplantation. The optimal starting date of this growth factor support has not been established yet, but many engraftment studies now recommend the fifth day after stem cell infusion (Day 5).

Study Design And Methods: After switching the start date of granulocyte-colony-stimulating factor (G-CSF) support from the day of transplant (Day 0 group), to Day 5 after stem cell infusion (Day 5 group), the impression arose that there was an associated delay in engraftment of both white blood cells and platelets (PLTs).

Prediction of engraftment after autologous peripheral blood progenitor cell transplantation: CD34, colony-forming unit-granulocyte-macrophage, or both?

Background: The rate of hematologic recovery after peripheral blood progenitor cell (PBPC) transplantation is influenced by the dose of progenitor cells. Enumeration of cells that express CD34+ on their surface is the most frequently used method to determine progenitor cell dose. In vitro growth of myeloid progenitor cells (colony-forming unit-granulocyte-macrophage [CFU-GM]) requires more time and resources, but may add predictive information.

Delayed ABLC prophylaxis after allogeneic stem-cell transplantation.

Invasive fungal infections (IFI) are frequent causes of mortality after allogeneic stem-cell transplantation (SCT). A very important risk factor for IFI is the use of steroids. We used a risk-based chemoprevention in an open-labelled pilot study.

Transplantation of hematopoietic stem cells from the peripheral blood.

Hematopoietic stem cells can be collected from the peripheral blood. These hematopoietic stem cells (HSC), or better progenitor cells, are mostly expressed as the percentage of cells than react with CD34 antibodies or that form colonies in semi-solid medium (CFU-GM). Under steady-state conditions the number of HSC is much lower in peripheral blood than in bone marrow.

Hypereosinophilic syndrome: long-term remission following allogeneic stem cell transplant in spite of transient eosinophilia post-transplant.

A 38-year-old male with progressive myeloproliferative variant of hypereosinophilic syndrome (HES) underwent allogeneic bone marrow transplantation from a matched unrelated donor. The preparative regimen consisted of TBI, cytarabine, and cyclophosphamide. The graft was T-cell-depleted.

Peripheral blood progenitor cell transplantation.

Peripheral blood progenitor cells (PBPCs) have become increasingly popular over the last 15 years as the source of hematopoietic stem cells for transplantation. In the early 1990s, PBPCs replaced bone marrow (BM) as the preferred source of autologous stem cells, and recently the same phenomenon is seen in the allogeneic setting. Under steady-state conditions, the concentration of PBPCs (as defined by CFU-GM and/or CD34+ cells) is very low, and techniques were developed to increase markedly this concentration.

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