Biomedical subjects

James M Thompson

Publications and source records attributed to James M Thompson.

4 recordsLinked to original sources

PubMed2006

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. All patients received oral fluconazole or itraconazole (200-400 mg day(-1)) during their neutropenic episode. Starting on day +30, patients receiving prednisone > or =30 mg day(-1) were switched to twice weekly Amphotericin-B-lipid-complex (ABLC) in a dose of 4 mg kg(-1). Patients receiving lower steroid doses continued on the fluconazole/itraconazole prophylaxis. Between 1999 and 2002, 100 patients were enrolled and followed for IFI for 1 year. Seven patients were started on therapeutic daily ABLC treatment before day +30 because of documented or suspected IFI; four had definite or probable aspergillosis, and two had candidaemia. Thirty patients did not need prophylactic ABLC; only one developed candidaemia. Sixty-three patients received ABLC prophylaxis for a median of 52 days (range: 1-289). Seven of these patients developed IFI; one definite and two probable cases of aspergillosis, one case of probable Trichosporon beigelii infection, and three cases of candidaemia. The twice weekly ABLC was well tolerated. This risk-based chemoprevention appears to be effective and might diminish the role of steroids as risk factor for IFI after allogeneic SCT. The relatively high incidence of early IFI suggests that additional prophylaxis for IFI may be indicated for poor-risk patients prior to day +30.

Administration, Oral↗

PubMed2005

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. The patient had slow, but complete, hematologic recovery, and all cells were shown by VNTR analysis to be of donor origin. Five months after transplant, the patient developed prominent eosinophilia (peak 4.1 x 10(9)/L) with dermatographism and very high IL-5 levels. Eosinophils isolated to purity by cell sorting were all of donor origin. Mild increase in immunosuppression led to a normalization of eosinophil count after about 6 months. The patient is now 6 years after transplant, off all medications, and without evidence of disease. Allogeneic stem-cell transplantation is a potentially curative therapy for HES.

Adult↗

PubMed2002

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. Such mobilization techniques include daily injections of filgrastim (G-CSF) or a combination of chemotherapy and growth factors. Leukapheresis procedures allow the collection of large numbers of circulating white blood cells (and PBPCs). One or two leukapheresis procedures are often sufficient to obtain the minimum number of CD34+ cells considered necessary for prompt and consistent engraftment (i.e., 2.5-5.0 x 10(6)/kg). As compared to BM, autologous transplants with PBPCs lead to faster hematologic recovery and have few, if any, disadvantages. In the allogeneic arena, PBPCs also result in faster engraftment, but at a somewhat higher cost of chronic graft-versus-host disease (GvHD). This may be a double-edged sword leading to both increased graft-versus-tumor effects and increased morbidity. The rapid advances in the study of hematopoietic, and even earlier, stem cells will continue to shape the future of PBPC transplantation.

Antigens, CD34↗

PubMedDate not supplied

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. Mobilization with chemotherapy and/or growth factors may lead to a concentration of HSC in the peripheral blood that equals or exceeds the concentration in bone marrow. Transplantation of HSC from the peripheral blood results in faster hematologic recovery than HSC from bone marrow. This decreases the risk of infection and the need for blood-product support. For autologous stem-cell transplantation (SCT), the use of peripheral blood cells has completely replaced the use of bone marrow. For allogeneic SCT, on the other hand, the situation is more complex. Since peripheral blood contains more T-lymphocytes than bone marrow, the use of HSC from the peripheral blood increases the risk of graft-versus-host disease after allogeneic SCT. For patients with goodrisk leukemia, bone marrow is still preferred, but for patients with high-risk disease, peripheral blood SCT has become the therapy of choice.

Animals↗