Infectious complications after autologous CD34-selected peripheral blood stem cell transplantation

Bortezomib and Vorinostat Therapy as Maintenance Therapy Post-Autologous Transplant for Non-Hodgkin's Lymphoma Using R-BEAM or BEAM Transplant Conditioning Regimen

INTRODUCTION

The success of autologous stem cell transplantation (ASCT) for treating non-Hodgkin's lymphoma (NHL) is limited by its high relapse rates. To reduce the risk of relapse, additional maintenance therapy can be added post-transplant. In a non-transplant setting at the time of initiation of this study, both bortezomib and vorinostat had been studied alone or in combination for some NHL histology and showed some clinical activity. At our center, this combination therapy post-transplant for multiple myeloma showed acceptable toxicity. Therefore, it seemed reasonable to study this combination therapy post-ASCT for NHL.

METHODS

NHL patients underwent conditioning for ASCT with rituximab, carmustine, etoposide, cytarabine, melphalan/carmustine, etoposide, cytarabine, melphalan. After recovery from the acute transplant-related toxicity, combination therapy with IV bortezomib and oral vorinostat (BV) was started and was given for a total of 12 (28-day) cycles.

RESULTS

Nineteen patients received BV post-ASCT. The most common toxicities were hematologic, gastrointestinal, metabolic, fatigue, and peripheral neuropathy. With a median follow-up of 10.3 years, 11 patients (58%) are alive without disease progression and 12 patients (63%) are alive.

CONCLUSIONS

BV can be given post-ASCT for NHL and produces excellent disease-free and overall survival rates.

Assessing the utility of routine viral surveillance performed in children undergoing autologous stem cell transplantation at a single centre

We assessed the utility of routine viral surveillance for cytomegalovirus, Epstein-Barr virus and human adenovirus in children <16 years, undergoing autologous stem cell transplantation (ASCT) at a single centre over a 10-year period. A total of 85 ASCT were performed in 65 patients. Routine viral surveillance resulted in a high number of tests performed (median 20 tests per ASCT), without any clinically significant viral detections. These data support the limited clinical utility of routine viral surveillance in children undergoing ASCT. Adopting a clinically driven approach for viral testing is likely to be both cost-effective and safe.

Herpes Zoster Risk in Immunocompromised Adults in the United States: A Systematic Review

BACKGROUND

The primary reported risk factors for herpes zoster (HZ) include increasing age and immunodeficiency, yet estimates of HZ risk by immunocompromising condition have not been well characterized. We undertook a systematic literature review to estimate the HZ risk in immunocompromised patients.

METHODS

We systematically reviewed studies that examined the risk of HZ and associated complications in adult patients with hematopoietic cell transplants (HCT), cancer, human immunodeficiency virus (HIV), and solid organ transplant (SOT). We identified studies in PubMed, Embase, Medline, Cochrane, Scopus, and clinicaltrials.gov that presented original data from the United States and were published after 1992. We assessed the risk of bias with Cochrane or Grading of Recommendations Assessment, Development, and Evaluation methods.

RESULTS

We identified and screened 3765 records and synthesized 34 studies with low or moderate risks of bias. Most studies that were included (32/34) reported at least 1 estimate of the HZ cumulative incidence (range, 0-41%). There were 12 studies that reported HZ incidences that varied widely within and between immunocompromised populations. Incidence estimates ranged from 9 to 92 HZ cases/1000 patient-years and were highest in HCT, followed by hematologic malignancies, SOT, and solid tumor malignancies, and were lowest in people living with HIV. Among 17 HCT studies, the absence of or use of antiviral prophylaxis at <1 year post-transplant was associated with a higher HZ incidence.

CONCLUSIONS

HZ was common among all immunocompromised populations studied, exceeding the expected HZ incidence among immunocompetent adults aged ≥60 years. Better evidence of the incidence of HZ complications and their severity in immunocompromised populations is needed to inform economic and HZ vaccine policies.

Prophylaxis, diagnosis and therapy of infections in patients undergoing high-dose chemotherapy and autologous haematopoietic stem cell transplantation. 2020 update of the recommendations of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

To ensure the safety of high-dose chemotherapy and autologous stem cell transplantation (HDC/ASCT), evidence-based recommendations on infectious complications after HDC/ASCT are given. This guideline not only focuses on patients with haematological malignancies but also addresses the specifics of HDC/ASCT patients with solid tumours or autoimmune disorders. In addition to HBV and HCV, HEV screening is nowadays mandatory prior to ASCT. For patients with HBs antigen and/or anti-HBc antibody positivity, HBV nucleic acid testing is strongly recommended for 6 months after HDC/ASCT or for the duration of a respective maintenance therapy. Prevention of VZV reactivation by vaccination is strongly recommended. Cotrimoxazole for the prevention of Pneumocystis jirovecii is supported. Invasive fungal diseases are less frequent after HDC/ASCT, therefore, primary systemic antifungal prophylaxis is not recommended. Data do not support a benefit of protective room ventilation e.g. HEPA filtration. Thus, AGIHO only supports this technique with marginal strength. Fluoroquinolone prophylaxis is recommended to prevent bacterial infections, although a survival advantage has not been demonstrated.

Impact of γδ T cells on clinical outcome of hematopoietic stem cell transplantation: systematic review and meta-analysis

Allogeneic hematopoietic stem cell transplantation (HSCT) using αβ T-/B-cell-depleted grafts recently emerged as a transplant strategy and highlighted the potential role of γδ T cells on HSCT outcomes. Our aim was to scrutinize available evidence of γδ T-cell impact on relapse, infections, survival, and acute graft-versus-host disease (aGVHD). We performed a systematic review and meta-analysis of studies assessing γδ T cells in HSCT. We searched PubMed, Web of Science, Scopus, and conference abstracts from inception to March 2019 for relevant studies. We included all studies that assessed γδ T cells associated with HSCT. Data were extracted independently by 2 investigators based on strict selection criteria. A random-effects model was used to pool outcomes across studies. Primary outcome was disease relapse. We also assessed infections, survival, and aGVHD incidence. The review was registered with PROSPERO (CRD42019133344). Our search returned 2412 studies, of which 11 (919 patients) were eligible for meta-analysis. Median follow-up was 30 months (interquartile range, 22-32). High γδ T-cell values after HSCT were associated with less disease relapse (risk ratio [RR], 0.58; 95% confidence interval [95% CI], 0.40-0.84; P = .004; I2 = 0%), fewer viral infections (RR, 0.59; 95% CI, 0.43-0.82; P = .002; I2 = 0%) and higher overall (HR, 0.28; 95% CI, 0.18-0.44; P < .00001; I2 = 0%) and disease-free survivals (HR 0.29; 95% CI, 0.18-0.48; P < .00001; I2 = 0%). We found no association between high γδ T-cell values and aGVHD incidence (RR, 0.72; 95% CI, 0.41-1.27; P = .26; I2 = 0%). In conclusion, high γδ T cells after HSCT is associated with a favorable clinical outcome but not with aGVHD development, suggesting that γδ T cells have a significant effect on the success of HSCT. This study was registered with PROSPERO as #CRD42019133344.

Bortezomib and Vorinostat Therapy as Maintenance Therapy after Autologous Transplant for Multiple Myeloma

BACKGROUND

In multiple myeloma (MM), relapse is a frequent complication after autologous hematopoietic stem cell transplant (ASCT). To reduce the risk of relapse, additional therapy has been added post-ASCT. In a nontransplant relapse setting, the combination of intravenous bortezomib and oral vorinostat (BV) was studied and showed efficacy. Therefore, it was reasonable to study this combination therapy post-ASCT.

PATIENTS AND METHODS

We report on BV given post-ASCT. All 30 patients underwent conditioning for ASCT with high-dose melphalan. After recovery from the acute transplant-related toxicity, BV therapy was started and given for a total of 12 (28-day) cycles.

RESULTS

The most common toxicities were hematological, gastrointestinal (diarrhea and nausea), fatigue, and peripheral neuropathy. The median follow-up for BV patients is 7.8 (range: 6.12-9.03) years. After BV therapy, 18 patients (60%) are alive, and 9 (30%) are alive without disease progression.

CONCLUSIONS

BV can be given post-ASCT with an acceptable toxicity profile and produces reasonable disease-free and overall survival rates. A randomized study comparing the BV regimen to single-agent lenalidomide or bortezomib is needed.

Recombinant Zoster Vaccine Significantly Reduces the Impact on Quality of Life Caused by Herpes Zoster in Adult Autologous Hematopoietic Stem Cell Transplant Recipients: A Randomized Placebo-Controlled Trial (ZOE-HSCT)

Herpes zoster (HZ) can have a substantial impact on quality of life (QoL). The vaccine efficacy (VE) of a recombinant zoster vaccine (RZV) was 68.2% (95% confidence interval [CI], 55.6% to 77.5%) in a phase 3 study in adult autologous hematopoietic stem cell transplant (HSCT) recipients (NCT01610414). Herein, we report the impact of RZV on patients' QoL. Autologous HSCT recipients were randomized 1:1 to receive 2 doses of RZV or placebo, given 1 to 2 months apart. QoL was measured by the Short Form Survey-36 and Euro-QoL-5 Dimension at baseline, 1 month, and 1 year postdose 2 and during suspected HZ episodes with the Zoster Brief Pain Inventory (ZBPI). The RZV impact on ZBPI burden of illness and burden of interference scores was estimated. The 2 scores were calculated from the area under the curve (days 0 to 182) of the ZBPI worst pain and ZBPI activities of daily living scores, respectively, assuming a score of 0 for patients not having a confirmed HZ episode. The ZBPI maximum worst pain score was significantly lower in the RZV than placebo group (mean: 5.8 versus 7.1, P = .011). Consequently, the VE estimates for HZ burden of illness (82.5%; 95% CI, 73.6 to 91.4) and burden of interference (82.8%; 95% CI, 73.3 to 92.3) were higher than the HZ VE estimate (ie, 68.2%). RZV showed significantly better QoL scores than placebo 1 week following rash onset among patients with confirmed HZ. In addition to reducing the risk of HZ and its complications, RZV significantly reduced the impact of HZ on patients' QoL in those who developed breakthrough disease.

Host and Graft Factors Impacting Infection Risk in Hematopoietic Cell Transplantation

Infection contributes significantly to morbidity and mortality in hematopoietic cell transplantation. A complex interplay of host, graft, and technical factors contributes to infectious risk in the recipient. Host factors such as age, underlying disease, and comorbidities; central venous access; and the preparative regimen contribute to mucosal disruption, organ dysfunction, and immunodeficiency before hematopoietic cell transplantation. Graft factors, including donor histocompatibility, cell source, and graft components, along with immunosuppression and graft-versus-host disease, contribute to the speed of immune reconstitution. Evaluation of these factors, plus previous and posttransplant exposure to pathogens, is necessary to best assess an individual recipient's infection risk.

Results from Two Consecutive Studies of Consolidation Therapy after Autologous Transplant for Multiple Myeloma: Thalidomide, Dexamethasone, and Clarithromycin or Lenalidomide, Dexamethasone, and Clarithromycin

BACKGROUND

In multiple myeloma (MM), relapse is a problem after autologous hematopoietic stem cell transplantation (ASCT). In the nontransplant setting, thalidomide/dexamethasone/clarithromycin (BLT-D) and lenalidomide/dexamethasone/clarithromycin (BiRd) achieve responses with acceptable toxicity. Both regimens are reasonable objects of study in the post-ASCT setting.

PATIENTS AND METHODS

We report on BLT-D and BiRd given post-ASCT. Studies were conducted consecutively. After recovery from ASCT, therapy was started. All 3 drugs were given for 1 year, and then immunomodulatory drugs alone were given as long as tolerated or until disease progression.

RESULTS

For BLT-D, the most common toxicity was peripheral neuropathy (PN). For BiRd, infection, PN, and neutropenia were the most common adverse events. BiRd was associated with a higher frequency of secondary cancers. The median follow-up for BLT-D was 10.2 years (range 8.6-10.7) and for BiRd it was 7.5 years (range 6.4-8.4). After BLT-D, 18 patients (67%) were alive and 10 (37%) were alive without disease progression, and after BiRd, 18 patients (58%) were alive and 10 (32%) were alive without disease progression.

CONCLUSIONS

BLT-D and BiRd can be given post-ASCT with different toxicity profiles and comparable disease-free and overall survival rates. A randomized study comparing these regimens to single-agent lenalidomide is needed to determine which approach is superior. Key Message: Relapse of MM is a major problem after ASCT. Strategies are needed post-ASCT to improve outcomes. In the nontransplant setting, thalidomide or lenalidomide/dexamethasone/clarithromycin treat MM with acceptable toxicity. We, thus, studied both regimens post- ASCT. They can be given with different toxicity profiles and result in good disease control.

Cytomegalovirus infection in patients with haematological diseases and after autologous stem cell transplantation as consolidation: a single-centre study

Because of the widespread use of immunosuppressive drugs, CMV infection is one of the most important causes of morbidity and mortality in patients with haematological malignancies worldwide. The aim of the study was to retrospectively analyse the epidemiology of CMV infection in haematological patients. Between 2008 and 2014, 1238 quantitative CMV DNA detections from plasma specimens were performed. These specimens were collected from 271 patients with haematological malignancy. Patients were grouped on the basis of underlying diseases (lymphoid and myeloid malignancies and other haematological diseases). In the lymphoid and myeloid groups, we distinguished ASCT and non-ASCT groups. During the studied period, the majority of examined patients (82.6 %) were treated with lymphoproliferative disease. A total of 126 (46.5 %) patients underwent ASCT, while 145 (53.5 %) did not have stem cell transplantation. A total of 118 (9.5 %) of 1238 plasma specimens proved to be positive for CMV DNA; these specimens were collected from 66 (24.4 %) patients. Twenty-four (16.6 %) of 145 non-ASCT patients had CMV PCR positive specimens. Among non-ASCT patients with positive CMV PCR results, 10 patients were asymptomatic, 14 had symptomatic reactivation, while 2 had CMV disease. In the ASCT group, 42 (33.3 %) patients had CMV PCR positive samples. CMV reactivation was asymptomatic in 34 (81 %) cases, and 8 (19 %) patients had symptomatic reactivation. In the non-ASCT group, the rate of CMV infection is low. In the ASCT group, the prevalence of CMV infection was higher than in the non-ASCT group, but the majority of CMV infection was asymptomatic and only small number of patients had symptomatic reactivation. Thus, our results also showed that the use of routine CMV DNA monitoring is not necessary in patients with haematological malignancies not receiving fludarabine-containing regimen or alemtuzumab, in spite of this to decrease the mortality we have to consider the use of molecular tests in case of suspected infectious conditions.

Parainfluenza virus infections in hematopoietic cell transplant recipients and hematologic malignancy patients: A systematic review

Parainfluenza viral infections are increasingly recognized as common causes of morbidity and mortality in cancer patients, particularly in hematopoietic cell transplant (HCT) recipients and hematologic malignancy (HM) patients because of their immunocompromised status and susceptibility to lower respiratory tract infections. Advances in diagnostic methods, including polymerase chain reaction, have led to increased identification and awareness of these infections. Lack of consensus on clinically significant endpoints and the small number of patients affected in each cancer institution every year make it difficult to assess the efficacy of new or available antiviral drugs. In this systematic review, we summarized data from all published studies on parainfluenza virus infections in HM patients and HCT recipients, focusing on incidence, risk factors, long-term outcomes, mortality, prevention, and management with available or new investigational agents. Vaccines against these viruses are lacking; thus, infection control measures remain the mainstay for preventing nosocomial spread. A multi-institutional collaborative effort is recommended to standardize and validate clinical endpoints for PIV infections, which will be essential for determining efficacy of future vaccine and antiviral therapies.

High-dose chemotherapy followed by autologous and allogeneic hematopoietic stem cell transplantation in patients with follicular non-Hodgkin’s lymphoma in the rituximab era

High-dose chemotherapy in lymphomas, and mainly non-Hodgkin’s lymphomas, has been advancing since the 1970s. This therapeutic strategy is based on the supposed existence of a dose-response curve for cytotoxic agents. However, the available data are contradictory, so high-dose chemotherapy cannot be guaranteed as consolidation treatment for first-remission follicular lymphoma or diffuse large cell lymphoma. The objective of this paper is to review the current knowledge about high-dose chemotherapy followed by hematopoietic stem cell transplantation in follicular non-Hodgkin’s lymphoma. The published studies on follicular lymphoma after first remission, recurrent follicular lymphoma, and transformed follicular ­lymphoma were assessed together with the data available on diffuse large cell lymphoma. During analysis of the studies, difficulties were encountered in comparing studies due to the heterogeneous nature of the data. High-dose chemotherapy as consolidation treatment after first remission or in recurrent or refractory disease was also analyzed.

Autologous hematopoietic cell transplantation: an update for clinicians

High-dose chemotherapy followed by transplantation of autologous hematopoietic progenitor cells has a proven track record of safety and efficacy in hematological malignancies and select solid tumors. The near-universal use of peripheral blood stem cells as source for autografts, routine growth factor support, and antimicrobial prophylaxis post transplantation has improved the safety of this procedure. However, the advent of highly active novel therapies in the last few years warrants reappraisal of the role of autologous transplantation in the therapeutic armamentarium of malignant disorder. This review summarizes the current role of autologous transplantation for hematological malignancies, discusses modern standards for patient selection, and highlights long-term care issues of transplant survivors from an internist's perspective. Role of tumor purging in autologous transplantation, novel transplant conditioning regimens, and post-transplant therapies to prevent disease relapse are reviewed.

Prevention of infection in cancer patients

Patients with cancer vary regarding the nature and level of immunocompromise. Both the underlying malignancy and therapy can influence risk of infectious complications. Therefore, decisions about antimicrobial prophylaxis must be guided by a number of factors: (1) the risk of infection; (2) the potential severity of infection and the likelihood of response to therapy; and (3) the safety and efficacy of antimicrobial prophylaxis. The potential for selection for antibiotic-resistant pathogens should also inform decisions about prophylaxis. When assessing clinical trial data on antimicrobial prophylaxis, two major criteria should be considered: the quality of studies supporting prophylaxis (randomized, blinded studies are optimal) and the expected benefit of prophylaxis, measured in terms of prevention of morbidity and potentially mortality. This chapter reviews the epidemiology and clinical trial data on prophylaxis against the major bacterial, viral, and fungal diseases in patients with cancer. Gaps in knowledge and alternative approaches, such as the use of newer diagnostics, are discussed.

Absence of intraocular infections after hematopoietic stem cell transplantation at a single center: the experience with current preventive regimens

PURPOSE

To investigate the prevalence of intraocular infections after allogeneic stem cell transplantation (allo-SCT).

METHODS

The study design was a single institutional retrospective noncomparative cohort of 135 consecutive patients in 2006 and 2007 who underwent allo-SCT for hematological malignancy. The primary outcome was the development of intraocular infections after allo-SCT and secondary outcome consisted of development of other ocular disorders during follow-up.

RESULTS

The most frequent ocular sequel to allo-SCT included ocular graft-versus-host disease (GvHD), which developed in 37/135 patients (27%). Intraocular infection occurred in 1 of 135 patients (0.7%). This patient developed infectious chorioretinitis together with osteomyelitis, endocarditis, and brain abscess with fungus Scedosporium and was successfully treated with a combination of voriconazole, amphotericine B, and surgical interventions. Viral and/or bacterial intraocular infections were not observed at all.

CONCLUSIONS

Intraocular infections after allo-SCT are currently uncommon due to systematic use of preemptive treatment regimens, frequent controls, and early treatment of systemic infections.

Controversies and recent advances in hematopoietic cell transplantation for follicular non-hodgkin lymphoma

Commonly designated as an indolent non-Hodgkin lymphoma, follicular lymphoma (FL) presents with striking pathobiological and clinical heterogeneity. Initial management strategies for FL have evolved to involve combination chemoimmunotherapy and/or radio-immunoconjugates. Unfortunately even with the best available nontransplant treatment, which nowadays results in higher frequency of response, FL remains incurable. Although considered a feasible therapeutic option, the use of hematopoietic cell transplantation (HCT) remains controversial. The appropriate timing, graft source, and intensity of HCT conditioning regimens in FL are often matters of debate. Herein we review the available published data pertaining to the use of autologous or allogeneic HCT in patients with FL across different stages of the disease, discuss major recent advances in the field, and highlight avenues for future research. The current literature does not support a role of HCT for FL in first remission, but in the relapsed setting autologous HCT remains appropriate for patients with early chemosensitive relapses, while allogeneic transplantation remains the sole curative modality for this disease, in relatively younger patients without significant comorbidities.

Reappraising the role of autologous transplantation for indolent B-cell lymphomas in the chemoimmunotherapy era: is it still relevant?

The role of autologous hematopoietic cell transplantation (auto-HCT) in the management of indolent non-Hodgkin lymphomas (NHL) is shrouded in controversy. The outcomes of conventional therapies for many indolent lymphoma subtypes have dramatically improved over the last several years with the use of monoclonal antibodies, maintenance therapy programs and with the incorporation of radio-immunoconjugates. These significant advances in the armamentarium of lymphoma therapeutics warrant reappraisal of the current role of auto-HCT in the treatment algorithm of indolent NHL. Prospective randomized studies comparing contemporary chemoimmunotherapies against auto-HCT are lacking, leading to significant debate about the role and timing of auto-HCT for indolent NHL in the modern era. Although autografting for follicular lymphoma (FL) in first remission has been largely abandoned, it remains a useful modality for relapsed disease, especially for the subgroup of patients who are not candidates for allogeneic transplantation with a curative intent. Auto-HCT can provide durable disease control in chemosensitive transformed FL and mantle cell lymphoma (MCL) in first remission, with relatively low toxicity, and remains appropriate in chemoimmunotherapy era. Contemporary data are also reviewed to clarify the often underutilized role of autografting in relapsed MCL and other less frequent indolent NHL histologies. The biological basis of the increased risks of second malignancies with auto-HCT are reviewed to identify strategies designed to mitigate this risk by, for example, avoiding exposure to genotoxic agents, planning early stem cell collection/cryopreservation and minimizing the use of TBI with transplant conditioning, and so on. Genetic testing able to identify patients at high risk of therapy-related complications and novel post-transplant immune therapies with the potential of transforming autografting in indolent NHL from a remission-extending therapy to a curative modality are discussed to examine the possibly expanding role of auto-HCT for lymphoid malignancies in the coming years.

Stem Cell Transplantation for Lymphoma Patients with HIV Infection

The advent of Highly Active Antiretroviral Therapy (HAART) has radically changed incidence characteristics and prognosis of HIV-positive patients affected by lymphomas. At this time there is consensus in the literature that, in first line, HIV-positive patients should always be treated with curative intent preferentially following the same approach used in the HIV-negative counterpart. On the contrary, an approach of salvage therapy in HIV-positive lymphomas is still a matter of debate given that for a wide range of relapsed or resistant HIV-negative Hodgkin's disease (HD) and non-Hodgkin lymphoma (NHL) patients, autologous peripheral or allogeneic stem cell transplantation are among the established options. In the pre-HAART era, therapeutic options derived from pioneering experiences gave only anecdotal success, either when transplantation was used to cure lymphomas or to improve HIV infection itself. Concerns relating to the entity, quality, and kinetics of early and late immune reconstitutions and the possible worsening of underlying viroimmunological conditions were additional obstacles. Currently, around 100 relapsed or resistant HIV-positive lymphomas have been treated with an autologous peripheral stem cell transplantation (APSCT) in the HAART era. Published data compared favorably with any previous salvage attempt showing a percentage of complete remission ranging from 48% to 90%, and overall survival ranging from 36% to 85% at median follow-up approaching 3 years. However, experiences are still limited and have given somewhat confounding indications, especially concerning timing and patients' selection for APSCT and feasibility and outcome for allogeneic stem cell transplant. Moreover, little data exist on the kinetics of immunological reconstitution after APSCT or relevant to the outcome of HIV infection. The aim of this review is to discuss current knowledge of the role of allogeneic and autologous stem cell transplantation as a modality in the cure of HIV and hemopoietic cancer patients. Several topics dealing with practical aspects concerning the management of APSCT in HIV-positive patients, including patient selection, timing of transplant, conditioning regimen, and relapse or nonrelapse mortality, are discussed. Data relating to the effects of mobilization and transplantation on virological parameters and pre- and posttransplant immune reconstitution are reviewed. Finally, in this review, we examine several ethical and legal issues relative to banking infected or potentially infected peripheral blood stem cells and we describe our experience and strategies to protect positive and negative donors/recipients and the health of caretakers.

CD154 expression is associated with neutralizing antibody titer levels postinfluenza vaccination in stem cell transplant patients and healthy adults

We undertook a prospective longitudinal study to examine humoral and cellular immune responses to influenza vaccination in hematopoietic cell transplant (HCT) patients and healthy adults. Healthy volunteers and HCT patients had blood samples taken prior to influenza vaccination and 30, 90, and 180 days postvaccination. Serum from pre- and postvaccination time points were tested for influenza A IgG and IgM by ELISA as well as tested for neutralizing antibody (NAb) titers via hemagglutination inhibition assay. Polychromatic flow cytometry was used to examine CD4(+) T cells for levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and CD154 (CD40 ligand) expression after stimulation with inactivated flu virus. In healthy subjects, we found a significant increase in Influenza A IgG and IgM levels as well as an increase in NAb titers pre- and post-influenza vaccination. Notably, NAb titers of most HCT patients did not rise to a protective level postvaccination. CD4(+) T cell expression of CD154 and cytokine responses were significantly reduced in HCT recipients compared to healthy adults. A lack of B cell reconstitution and dysfunctional CD4 T cell costimulation (as marked by low CD154 expression) is associated with low NAb levels postvaccination in HCT patients.

Cytomegalovirus infection in children undergoing hematopoietic stem cell transplantation in Chile

BACKGROUND

Cytomegalovirus (CMV) infection remains as an important cause of morbidity and mortality in children undergoing hematopoietic stem cell transplantation (HSCT). Our aim was to assess the incidence, risk factors, and outcome related to CMV infection in children after HSCT in a developing country.

METHODS

From October 1, 1999, to December 31, 2005, we prospectively studied all patients admitted to the HSCT unit at Hospital Luis Calvo Mackenna in Santiago, Chile. Serologic studies before transplantation and weekly CMV infection surveillance (antigenemia or quantitative PCR) were routinely obtained. Patients with positive antigenemia or quantitative PCR received pre-emptive therapy with ganciclovir, and cases of unfavorable clinical evolution, persistent positive antigenemia, or quantitative PCR after 14 days of ganciclovir were treated with foscarnet.

RESULTS

Ninety-seven patients received HSCT. Their median age was 8 years (range, 3 months to 24 years) and their overall survival was 67%. CMV reactivation was diagnosed in 26 patients. Of these, three developed CMV disease (two interstitial pneumonia, one hemorrhagic cystitis). One of the patients with pneumonia died. Risk factors identified were pre-transplant serologic status (positive recipient), acute and chronic graft versus host disease (GvHD), GvHD prophylaxis, and treatment with antithymocyte globulin.

CONCLUSIONS

The rate and prognosis of CMV infection among children treated at our HSCT unit is similar to those reported from industrialized countries. These findings reflect adequate prevention and management of CMV infection within our program.

Role of hematopoietic stem cell transplant in the management of follicular lymphoma

Despite decades of published data regarding the application of autologous and allogeneic stem cell transplant in patients with follicular lymphoma, there remain no uniform indications for its use in this disease. Autologous transplant has been shown to lead to longer progression-free survival times in randomized trials when compared with postremission interferon-based chemoimmunotherapy. However, the development of rituximab and its use in frontline, salvage, and maintenance therapy complicates the decision to pursue autologous transplant, a modality developed prior to the advent of anti-CD20 monoclonal antibodies. Allogeneic transplant offers the advantages of lymphoma-free grafts and the immunologic graft-versus-lymphoma effect. These factors may confer the possibility of long-term remission, though historically they have been accompanied by high rates of upfront morbidity and mortality, especially in heavily pretreated patients with a poor performance status or chemotherapy-refractory disease. Advances in patient selection, human leukocyte antigen (HLA) matching, conditioning regimens, and supportive care have reduced transplant-related mortality and the incidence of graft-versus-host disease. Recently published data focus on the incorporation of rituximab and radioimmunoconjugates prior to, during, and following autologous transplant. Furthermore, reduced-intensity allogeneic stem cell transplantation has increasingly been used for relapsed follicular lymphoma patients with comorbidities or advanced age. Several recent reports suggest that reduced-intensity regimens may provide a high likelihood of long-term disease-free survival for patients up to 70 years of age with a good performance status, chemotherapy-sensitive disease, and HLA-matched sibling donors. Such patients with relapsed disease should be referred to a transplant center that can enroll them in one of the forthcoming clinical trials that aim to confirm these outcomes.

Virus reactivation in high-risk non-Hodgkin's lymphoma patients after autologous CD34+ -selected peripheral blood progenitor cell transplantation

CD34+-selected peripheral blood progenitor cells (PBPCs) may not only reduce contaminated tumor cells but also compromise immunologic reconstitution and increase incidence of infections after transplantation. We analyzed the incidence of virus reactivation in CD34+-selected PBPCs autologous transplantation. From December 2001 to December 2004, ten high-risk aggressive non-Hodgkin's lymphoma (NHL) patients were enrolled in a program of high-dose chemotherapy plus autologous CD34+-selected PBPCs support. Viral screening studies, including clinical symptoms, physical examinations, hepatitis B virus (HBV)-DNA, cytomegalovirus (CMV)-polymerase chain reaction (PCR), rapid diagnosis of fluorescent antibody stain for herpes-simplex virus (HSV), and viral culture from blood, fluid or tissue were performed weekly during the first 3 months and then monthly for 1 year. Two of four patients (50%) who were HBV carriers developed HBV reactivation. The other two HBV carriers who received prophylactic lamivudine therapy did not develop HBV reactivation. Two patients (20%) developed cytomegalovirus (CMV) infection, and three patients (30%) developed HSV infection in total ten serum-positive patients. The possibility of virus reactivation might increase in NHL patients undergoing autologous CD34+-selected PBPC transplantation. Administering prophylactic antivirus therapy and closely following patient's clinical viral complications should be considered.

Epidemiology and outcome of invasive fungal infection in adult hematopoietic stem cell transplant recipients: analysis of Multicenter Prospective Antifungal Therapy (PATH) Alliance registry

BACKGROUND

With use of data from the Prospective Antifungal Therapy (PATH) Alliance registry, we performed this multicenter, prospective, observational study to assess the epidemiologic characters and outcomes of invasive fungal infection (IFI) in hematopoietic stem cell transplant (HSCT) recipients.

METHODS

Sixteen medical centers from North America reported data on adult HSCT recipients with proven or probable IFI during the period July 2004 through September 2007. The distribution of IFIs and rates of survival at 6 and 12 weeks after diagnosis were studied. We used logistic regression models to determine risk factors associated with 6-week mortality for allogeneic HSCT recipients with invasive aspergillosis (IA).

RESULTS

Two hundred thirty-four adult HSCT recipients with a total of 250 IFIs were included in this study. IA (59.2%) was the most frequent IFI, followed by invasive candidiasis (24.8%), zygomycosis (7.2%), and IFI due to other molds (6.8%). Voriconazole was the most frequently administered agent (68.4%); amphotericin B deoxycholate was administered to a few patients (2.1%). Ninety-three (46.7%) of 199 HSCT recipients with known outcome had died by week 12. The 6-week survival rate was significantly greater for patients with IA than for those with invasive candidiasis and for those with IFI due to the Zygomycetes or other molds (P < .07). The 6-week mortality rate for HSCT recipients with IA was 21.5%. At 6 weeks, there was a trend toward a worse outcome among allogeneic HSCT recipients with IA who received myeloablative conditioning (P = .07); absence of mechanical ventilation or/and hemodialysis (P = .01) were associated with improved survival.

CONCLUSIONS

IA remains the most commonly identified IFI among HSCT recipients, but rates of survival in persons with IA appear to have improved, compared with previously reported data. Invasive candidiasis and IFI due to molds other than Aspergillus species remain a significant problem in HSCT recipients.

Management of HSV, VZV and EBV infections in patients with hematological malignancies and after SCT: guidelines from the Second European Conference on Infections in Leukemia

These guidelines on the management of HSV, VZV and EBV infection in patients with hematological malignancies and after SCT were prepared by the European Conference on Infections in Leukemia following a predefined methodology. A PubMed search was conducted using the appropriate key words to identify studies pertinent to management of HSV, VZV and EBV infections. References of relevant articles and abstracts from recent hematology and SCT scientific meetings were also reviewed. Prospective and retrospective studies identified from the data sources were evaluated, and all data deemed relevant were included in this analysis. The clinical and scientific background was described and discussed, and the quality of evidence and level of recommendation were graded according to the Centers for Disease Control criteria.

Pretransplant neutropenia is associated with poor-risk cytogenetic features and increased infection-related mortality in patients with myelodysplastic syndromes

A retrospective cohort analysis was performed to determine the impact of neutropenia on the outcome of hematopoietic cell transplantation (HSCT) in patients with myelodysplasia (MDS). Among 291 consecutive patients, 178 (61%) had absolute neutrophil counts (ANCs) <1500/microL and 113 (39%) had ANCs > or =1500/microL within 2 weeks before HSCT. Neutropenic patients more often had poor-risk karyotypes (34% versus 12%, P < .0001) and high-risk International Prognostic Scoring System scores (37% versus 18%, P = .0006). After HSCT, the rate of infections caused by Gram-positive bacteria and invasive fungal infections was significantly increased among neutropenic patients (rate ratio [RR] 1.77, P = .02 and RR = 2.56, P = .03, respectively), whereas infections caused by Gram-negative bacteria were not affected (RR 1.33, P = .53). The hazards of nonrelapse mortality (NRM) (hazard ratio [HR] = 1.62 [1.1-2.4], P = .01), overall mortality (HR = 1.55 [1.1-2.1], P = 0.007), and infection-related mortality (HR = 2.22 [1.2-4.2], P = .01) were increased in neutropenic patients, whereas relapse, engraftment, and graft-versus-host-disease were not affected. After adjusting for cytogenetic risk and marrow myeloblast percentages, neutropenic patients remained at significant hazard for infection-related mortality (HR = 1.94 [1.0-3.8], P = .05), but not for overall mortality or NRM. We propose that intensified strategies to prevent infections should be implemented in MDS patients with preexisting neutropenia who undergo HSCT.

Fungal infections in recipients of hematopoietic stem cell transplants: results of the SEIFEM B-2004 study--Sorveglianza Epidemiologica Infezioni Fungine Nelle Emopatie Maligne

BACKGROUND

The purpose of our study was to evaluate the incidence and outcome of invasive fungal infection (IFI) among patients who underwent autologous or allogeneic hematopoietic stem cell transplantation (HSCT) at 11 Italian transplantation centers.

METHODS

This cohort-retrospective study, conducted during 1999-2003, involved HSCT patients admitted to 11 tertiary care centers or university hospitals in Italy, who developed IFIs (proven or probable).

RESULTS

Among 3228 patients who underwent HSCT (1249 allogeneic HSCT recipients and 1979 autologous HSCT recipients), IFI occurred in 121 patients (overall incidence, 3.7%). Ninety-one episodes (2.8% of all patients) were due to molds, and 30 (0.9%) were due to yeasts. Ninety-eight episodes (7.8%) occurred among the 1249 allogeneic HSCT recipients, and 23 (1.2%) occurred among the 1979 autologous HSCT recipients. The most frequent etiological agents were Aspergillus species (86 episodes) and Candida species (30 episodes). The overall mortality rate was 5.7% among allogeneic HSCT recipients and 0.4% among autologous HSCT recipients, whereas the attributable mortality rate registered in our population was 65.3% (72.4% for allogeneic HSCT recipients and 34.7% for autologous HSCT recipients). Etiology influenced the patients' outcomes: the attributable mortality rate for aspergillosis was 72.1% (77.2% and 14.3% for allogeneic and autologous HSCT recipients, respectively), and the rate for Candida IFI was 50% (57.1% and 43.8% for allogeneic and autologous HSCT recipients, respectively).

CONCLUSIONS

IFI represents a common complication for allogeneic HSCT recipients. Aspergillus species is the most frequently detected agent in these patients, and aspergillosis is characterized by a high mortality rate. Conversely, autologous HSCT recipients rarely develop aspergillosis, and the attributable mortality rate is markedly lower. Candidemia was observed less often than aspergillosis among both allogeneic and autologous HSCT recipients; furthermore, there was no difference in either the incidence of or the attributable mortality rate for candidemia among recipients of the 2 transplant types.

Active CMV disease does not always correlate with viral load detection

The use of quantitative cytomegalovirus (CMV) real-time polymerase chain reaction (RT-PCR) and preemptive ganciclovir therapy is replacing prophylaxis as the management of choice in high-risk patients undergoing stem cell transplantation (SCT). However, there are limited data defining its role in this setting. In the current retrospective single-centre study, quantitative RT-PCR was used to determine CMV in 577 consecutive patients undergoing SCT (172 allogeneic and 405 autologous) over a 5-year period. CMV RT-PCR was performed weekly until cessation of immunosuppression (allogeneic) or for 30 days post-SCT (autologous). Treatment was commenced after two consecutive positive results or a high copy on the first occasion (> 1000 copies/ml, > 3 log). The overall CMV reactivation rate in patients undergoing allogeneic SCT was 30%, with reactivation observed in 72% of high-risk patients (recipient positive patients). CMV end-organ disease was observed in eight patients (1%); of these, four were CMV RT-PCR negative at the time of diagnosis of end-organ CMV disease, with three remaining negative throughout the course of the disease. CMV-related mortality was recorded in three patients. The current data support a preemptive treatment strategy-based CMV RT-PCR, but indicate that in symptomatic patients, a negative CMV PCR result does not exclude CMV end-organ disease.

Immunotherapy with rituximab/interleukin-2 after autologous stem cell transplantation as treatment for CD20+ non-Hodgkin's lymphoma

BACKGROUND

Relapse of non-Hodgkin's lymphoma (NHL) remains a problem after autologous stem cell transplantation (ASCT). Soon after ASCT, the immune system is not very active, and this immune incompetence could thus result in decreased ability for immune-mediated tumor eradication. The early addition of immunotherapy after ASCT might decrease the incidence of relapse and prolong survival. In an initial phase I/II trial at our center, the immune modulator interleukin-2 (IL-2) increased over baseline natural killer and lymphokine-activated killer activity in vitro. Because rituximab can lyse CD20-bearing cells by antibody-dependent cellular cytotoxicity, adding IL-2 to rituximab might boost its effectiveness. It thus seemed reasonable to study this combination after ASCT. The results of our phase II study are reported herein.

PATIENTS AND METHODS

Twenty patients with CD20+ NHL who had ASCT were treated. The median time to starting therapy was 79 days (range, 49-100 days) after transplantation.

RESULTS

The majority of patients reported grade <or= 2 erythema, induration and pain at IL-2 injection sites, flu-like symptoms, and worsening fatigue. Neutropenia that responded to granulocyte colony-stimulating factor was the most common grade 3/4 toxicity, seen in 45% of patients. There were no treatment-related deaths. Eighteen of 20 patients remain alive in complete remission, with a median follow-up of 55.5 months (range, 17-64 months).

CONCLUSION

Interleukin-2/rituximab can be administered after ASCT with manageable toxicity. A randomized trial is under way to address whether this combination therapy is beneficial to patients with NHL who have had ASCT.

Reduced incidence of acute and chronic graft-versus-host disease with the addition of thymoglobulin to a targeted busulfan/cyclophosphamide regimen

To reduce the incidence of graft-versus-host disease (GVHD), we added Thymoglobulin (THY) to dose-adjusted oral busulfan plus cyclophosphamide (targeted BUCY). The starting dose of THY was 4.5 mg/kg given over days -3, -2, and -1, escalated in steps of 1.5 mg/kg in cohorts of 15 evaluable patients. Escalation was dependent on acute GVHD incidence and Epstein-Barr virus reactivation. Fifty-six patients with myelodysplastic syndrome and other myeloid disorders underwent transplantation with peripheral blood progenitor cells from related (n=30) or unrelated (n=26) donors. All but 2 patients achieved engraftment, and 56% survived in remission beyond 1 year. The incidence of acute GVHD was 50%, and that of chronic GVHD was 34%. The highest THY dose was 6.0 mg/kg, a dose at which 1 patient experienced Epstein-Barr virus reactivation. Nine patients did not receive the prescribed THY dose. Results were comparable for related and unrelated transplants and for patients given 4.5 or 6.0 mg/kg THY. Among 27 myelodysplastic syndrome patients (14 with related and 13 with unrelated donors) who underwent transplantation concurrently with targeted BUCY without THY, the incidence of acute and chronic GVHD was 82%. Thus, THY 4.5 to 6.0 mg/kg seemed beneficial for GVHD prevention in BUCY-conditioned patients who underwent transplantation with peripheral blood progenitor cells, although relapse-free survival did not differ significantly from that in comparable historical controls not given THY.

Antiviral prophylaxis in patients with haematological malignancies and solid tumours: Guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society for Hematology and Oncology (DGHO)

Morbidity and mortality in patients with malignancies are increased by viral infections. These mostly are reactivations of asymptomatic latent infections. They primarily concern clinical entities associated with the reactivation of herpes viruses, such as varicella zoster virus (VZV) and cytomegalovirus (CMV). Respiratory tract infections caused by influenza, parainfluenza or respiratory syncytial virus (RSV) are less common. Since reactivation of latent infections has major clinical impact, antiviral prophylaxis is an attractive approach for patients expecting immunosuppression. The main risk factor for clinically relevant reactivation is profound disruption of cellular immune response. Duration and severity of chemotherapy induced neutropenia are of lesser importance. The risk of viral complications rises significantly in the presence of sustained suppression of T-cell function, e.g. in recipients of allogeneic stem cell transplants or of alemtuzumab (Campath-1H) antibody therapy. The objective of this guideline is to review the basis of prophylactic strategies and to provide recommendations for clinicians treating patients with haematological malignancies and solid tumors.

Review of Epidemiology, Diagnosis, and Treatment of Invasive Mould Infections in Allogeneic Hematopoietic Stem Cell Transplant Recipients

Invasive mould infections are a major cause of morbidity and mortality in hematopoietic stem cell transplant recipients (HSCT). Allogeneic HSCT recipients are at substantially higher risk than autologous HSCT recipients. Although neutropenia following the conditioning regimen remains an important risk factor for opportunistic fungal infections, most cases of invasive mould infection in allogeneic HSCT recipients occur after neutrophil recovery in the setting of potent immunosuppressive therapy for graft-versus-host disease. Invasive aspergillosis is the most common mould infection. However, there has been an increased incidence of less common non-Aspergillus moulds that include zygomycetes, Fusarium sp., and Scedosporium sp. Reflecting a key need, important advances have been made in the antifungal armamentarium. Voriconazole has become a new standard of care as primary therapy for invasive aspergillosis based on superiority over amphotericin B. There is significant interest in combination therapy for invasive aspergillosis pairing voriconazole or an amphotericin B formulation with an echinocandin. There have also been advances in novel diagnostic methods that facilitate early detection of invasive fungal infections that include galactomannan and beta-glucan antigen detection and PCR using fungal specific primers. We review the epidemiology, diagnosis, and management of invasive mould infection in HSCT, with a focus on allogeneic recipients. We also discuss options for prevention and early treatment of invasive mould infections.

Infections after CD34-selected or unmanipulated autologous hematopoietic stem cell transplantation

Immune reconstitution may be delayed after CD34-selected compared with unmanipulated autologous peripheral blood stem cell transplantation (PBSCT), resulting in a theoretically increased risk of infections. In a case-control matched study we compared the incidence of infection in 25 recipients of CD34-selected PBSC (CD34 group) and 75 recipients of unmanipulated PBSC (PBSC group) transplants. The population included 52 males and 48 females suffering from non-Hodgkin's lymphoma (n = 32), Hodgkin's disease (n = 8), multiple myeloma (n = 40) or breast cancer (n = 20). Neutrophil engraftment was comparable in the two groups. The actuarial incidence of infection was similar in the two groups (56% vs. 49% at day 30, and 70% vs. 64% at 1 yr respectively). The proportion of patients with 1, 2 or 3 infections, the number of infectious event per patient (1.32 vs. 1.04; NS), the number of infections before day 15 or 30, between days 31 and 100 or after day 100, the risk of varicella-zoster virus or cytomegalovirus infection or disease, or the use of antibiotic or antifungal therapy, were not increased in the CD34 compared with the PBSC group. The main agents responsible for infection were bacteria, particularly gram-positive cocci, in both groups. Bacteremia accounted for 33% of all infectious events in the CD34 group vs. 16% in the PBSC group (P < 0.05). Fungal infections were rare. In conclusion, our results do not support the notion that CD34-selection of the graft is associated with an increased rate of infection after autologous PBSC transplantation. The role of extended infection prophylaxis should be evaluated.

T-lymphocyte reconstitution following rigorously T-cell-depleted versus unmodified autologous stem cell transplants

We compared the kinetics of T-cell recovery after extensive ex vivo and in vivo T-cell depleted autologous stem cell transplantation (SCT) for multiple sclerosis (MS; n=8) with unmodified SCT for hematological malignancies (HM; n=39). Both patient group showed a very protracted recovery of 'naive' CD4(+), 45R0(-) ( approximately CD45RA(+)) T-cells. Within the 'primed' CD4(+), 45R0(+) T-cells, the 'central memory' cells expressing the CD62L and CD27 markers were the slowest to recover. The repopulating T-cells were highly activated, as shown by increased expression of HLA-DR and the apoptosis marker CD95. The capability of CD4(+) and CD8(+) T-cells to produce IFN-gamma, IL-2 and TNF-alpha had reached normal ranges from 2 months post SCT onwards. Unexpectedly, the kinetics of T-cell recovery between 3 and 12 months post transplant was similar in T-depleted and unmodified SCT. Before SCT, the HM patients showed lymphopenia of all T-cell subsets, upregulated HLA-DR and CD95 expression and increased cytokine responses. We suggest that the similar kinetics of T-cell recovery in the two patient groups may be explained by the susceptibility to apoptosis of the activated CD4(+) T-cells in the autografts of the HM patients. This susceptibility to apoptosis would interfere with a swift and sustained CD4(+) T-cell regeneration post SCT.

Long-term acyclovir for prevention of varicella zoster virus disease after allogeneic hematopoietic cell transplantation--a randomized double-blind placebo-controlled study

Varicella-zoster virus (VZV) disease occurs in 30% of allogeneic hematopoietic cell transplant recipients who had a history of VZV infection. A safe and effective prevention strategy has not been established. In a double-blind controlled trial, 77 hematopoietic cell transplant recipients at risk for VZV reactivation were randomized to acyclovir 800 mg twice daily or placebo given from 1 to 2 months until 1 year after transplantation. VZV disease at 1 year was the primary end point; VZV disease after discontinuation of prophylaxis, VZV-specific T-cell immunity, herpes simplex virus (HSV) infection, cytomegalovirus (CMV) disease, survival, and safety were secondary end points. Acyclovir significantly reduced VZV infections at 1 year after transplantation (HR, 0.16; 95% CI, 0.035-0.74; P = .006). In the post-intervention observation period, this difference was not statistically significant (2 years: HR, 0.52; 95% CI, 0.21-1.3; 5 years: HR, 0.76; 95% CI, 0.36-1.6). There was no statistically significant difference in reconstitution of VZV-specific T-helper cell responses, HSV infections, CMV disease, chronic graft-versus-host disease, and overall survival between the groups. Acyclovir was well tolerated. Post-study VZV disease predominantly occurred in patients with continued need for systemic immunosuppression. In conclusion, acyclovir effectively and safely prevents VZV disease during the first year after hematopoietic cell transplantation. Periods of prophylaxis longer than 12 months may be beneficial for those hematopoietic cell transplant recipients on continued immune suppression.

Randomised comparison of two B-cell purging protocols for patients with B-cell non-Hodgkin lymphoma: in vivo purging with rituximab versus ex vivo purging with CliniMACS CD34 cell enrichment device

We investigated the feasibility, safety and efficacy of two B-cell purging methods in patients with CD20+ non-Hodgkin lymphoma (NHL) receiving autologous stsem cell transplantation. Myeloid and immune recoveries between the methods were compared. Twenty-seven patients were randomised to either in vivo purging with rituximab or ex vivo purging by CD34+ cell selection. Both purging methods were efficient at eliminating B-cells in infusates. When compared with in vivo purging, ex vivo purging was associated with CD34+ cell loss and delayed median neutrophil (10 d vs. 11 d) and platelet (12.5 d vs. 17 d) count recoveries. Lymphocyte recovery was similar in both groups, but immunoglobulin recovery was delayed after in vivo purging. Late-infectious complications were few in both arms. At a median follow-up of 27 months, 2-year probabilities of event-free survival (EFS) rates were 81% for in vivo purging and 76% for ex vivo purging (P = 0.66). When compared with 53 unpurged patients, all 27 purged patients had improved 3-year probabilities of overall survival (89% vs. 70%, P = 0.014) and a trend for improved EFS (78% vs. 57%, P = 0.075). In conclusion, although both purging methods were feasible and safe, rituximab purging was superior as it did not impair CD34+ cell mobilisation and was associated with faster myeloid recovery. Further studies are needed to determine whether rituximab purging is more effective than the use of unpurged autografts.

Autologous hematopoietic stem cell transplantation for autoimmune diseases

Ten years have passed since the first published consensus statement on the use of hematopoietic stem cell transplantation (HSCT) in the treatment of severe autoimmune disease (AD) appeared. During that time, around 700 patients suffering from severe AD have undergone HSCT in the frame of phase I/II clinical trials from over 20 countries including the US. The majority have received an autologous HSCT using one of a limited number of regimens, consistent with the original consensus statement. Long-term drug-free remissions, remission then relapse, no response and treatment-related mortality (TRM) were seen in all the subgroups of AD. An overall TRM of 7% was observed, with marked variation between ADs, i.e. 11% in systemic lupus erythematosus (SLE) and only 1 patient in rheumatoid arthritis (RA). Phase III prospective, comparative randomized trials are running or being planned in multiple sclerosis (MS), systemic sclerosis (SSc), SLE and RA. Basic science programs are also being undertaken to study the immunological mechanisms underlying the clinical events observed.

Progress in hematopoietic stem cell transplantation for autoimmune diseases

An international co-ordinated Phase I/II program commenced 8 years ago to study the role of profound immunoablation with hematopoietic stem cell transplantation in the treatment of severe, refractory autoimmune disease. Almost 700 patients have been treated for a variety of autoimmune diseases, mostly multiple sclerosis, systemic sclerosis, also referred to as scleroderma, systemic lupus erythematosis, rheumatoid arthritis and juvenile idiopathic arthritis. An overall treatment-related mortality of 7% was observed, with significant differences between diseases; 11% in systemic lupus erythematosis and only one patient with rheumatoid arthritis. Although outcomes are disparate in different diseases, there were significant durable, clinically useful remissions, relapses, and nonresponders in all groups. Although different protocols were employed, a clear advantage from the more intensive myeloablative regimens was not observed, although an increased toxicity did occur. The Phase I/II data was exploited in designing the Phase III randomized, comparative trials that are running in systemic sclerosis, multiple sclerosis and rheumatoid arthritis in Europe, and at the advanced planning stage in systemic sclerosis, multiple sclerosis and systemic lupus erythematosis in the USA. In parallel, a basic science program is proceeding with the prospective studies to improve understanding of the mechanisms of autoimmune disease activity and remission.

Immune restoration following hematopoietic stem cell transplantation: an evolving target

Hematopoietic stem cell transplantation (HSCT) is the definitive cure for many malignant and nonmalignant diseases. However, delays in immune reconstitution (IR) following HSCT significantly limit the success of transplantation and increase the risk for infection and disease relapse in the transplant recipient. Therefore, ways to measure and to manipulate immune recovery following HSCT are emerging and their success depends directly upon an enhanced understanding for the underlying mechanisms responsible for reconstituted immunity and hematopoiesis. Recent discoveries in the activation, function, and regulation of dendritic cell (DC), natural killer (NK) cell, and T-lymphocyte subtypes have been critical in developing immunotherapies used to prevent graft-versus-host disease and to enhance graft-versus-leukemia. For example, regulatory T cells that induce tolerance and NK receptor-tumor ligand disparities that result in tumor lysis are being used to minimize GVHD and tumor burden, respectively. Furthermore, expansion and modulation of immune effector cells are being used to augment hematopoietic and immune recovery and to decrease transplant-related toxicity in the transplant recipient. Specifically, DC expansion and incorporation into antitumor and anti-microbial vaccines is fast approaching application into clinical trials. This paper will review our current understanding for IR following HSCT and the novel ways in which to restore immune function and decrease transplant-related toxicity in the transplant recipient.

Reconstitution of HLA-A*2402-restricted cytomegalovirus-specific T-cells following stem cell transplantation

Cytomegalovirus (CMV)-specific immune reconstitution early after stem cell transplantation (SCT) was evaluated prospectively by detecting CD8+ T-cells, which recognize the peptide QYDPVAALF in the context of HLA-A*2402. Fifteen allogeneic SCT recipients were included in the study. All recipients and donors were seropositive for CMV and had the HLA-A*2402 allele. CMV-specific T-cells were detected as early as 1 month after transplantation, and their numbers increased to peak levels 2 to 5 months after transplantation. The numbers of CMV-specific T-cells in patients who developed grade II to IV acute graft-versus-host disease (GVHD) and received corticosteroids for acute GVHD were low in the early period after allogeneic SCT. There was a trend toward earlier reconstitution of CMV-specific CD8+ T-cells in allogeneic peripheral blood SCT (PBSCT) patients than in allogeneic bone marrow transplantation patients. The contribution of T-cells in the graft to the recovery of CMV-specific immune responses was also suggested by the finding that the reconstitution of CMV-specific CD8+ T-cells was delayed in CD34-selected autologous PBSCT compared with unpurged autologous PBSCT. The reconstitution of CMV-specific CD8+ T-cells was delayed in patients with CMV disease or recurrent CMV reactivation. These observations suggest that the detection of CMV-specific T-cells with an HLA-peptide tetramer is useful to assess immune reconstitution against CMV and to identify patients at risk for CMV disease or recurrent CMV reactivation after SCT.

Cytomegalovirus prophylaxis and treatment after hematopoietic stem cell transplantation in Canada: a description of current practices and comparison with Centers for Disease Control/Infectious Diseases Society of America/American Society for Blood and Marrow Transplantation guideline recommendations

Prevention and management of cytomegalovirus (CMV) disease after hematopoietic stem cell transplantation (HSCT) is critically important, but clinical practices have historically been heterogeneous. The Centers for Disease Control (CDC), as part of a larger clinical practice guideline initiative, has published evidence-based recommendations, but their effect on clinical practice has not been assessed. A survey was sent to all Canadian HSCT program directors to describe current practices. Current practices were subsequently compared with CDC guideline recommendations and with a Canadian survey published before the CDC guidelines. When current practices did not conform to guideline recommendations, a literature review was performed to determine whether current practices were supported by evidence published after the CDC guidelines. The survey response rate was 100%. Variability in practices was observed in several aspects of patient care, including (1) indications for CMV-negative blood products, (2) surveillance tests used to detect CMV infection, (3) duration of surveillance testing, (4) duration of maintenance treatment after preemptive therapy was initiated, and (5) treatment of CMV disease. Overall adherence to guideline recommendations was good, especially when they were supported by high-quality data. However, deviations from guideline recommendations were observed: (1) most Canadian allogeneic programs used shorter courses of preemptive therapy; (2) prevention measures aimed at late CMV disease were not systematically applied at most allogeneic programs; and (3) most autologous HSCT programs did not administer preemptive therapy even in high-risk recipients. When deviations occurred, recent evidence supported current practices in some instances (shorter courses of preemptive therapy) but not in others (absence of strategies to prevent late CMV disease). Compared with practices in Canada before publication of the CDC guidelines, a higher proportion of programs used CDC-recommended surveillance tests and treatment for CMV infection. Current practices in Canada remain heterogeneous. Discrepancies between current practices and CDC guideline recommendations occurred in situations either in which practices had changed in response to recently published data or in which evidence supporting a recommendation was poor. These results suggest an urgent need for the development of well-designed clinical trials. Incorporation of recent data into updated guidelines may be appropriate.

Stem cell transplantation in autoimmune diseases: an update

Immunosuppressive or immunomodulatory treatments are often used in patients with various autoimmune diseases (AID). However, since conventional treatments are rarely curative, alternative treatment methods have been looked for. Based on animal experiments and anecdotal case reports, stem cell transplantation (SCT) has received considerable attention in the treatment of severe autoimmune diseases during the last decade. This review summarizes current experience of SCT in patients this field. Although early experience shows some promise, randomized studies are necessary to evaluate the real value of autologous SCT in various autoimmune diseases. Since autologous SCT may not be curative in patients with AID, also evaluation of allogeneic SCT is important in the future.