Guidelines for preventing opportunistic infections among hematopoietic stem cell transplant recipients. Recommendations of CDC, the Infectious Disease Society of America, and the American Society of Blood and Marrow Transplantation

Dental evaluation and clearance prior to allogeneic hematopoietic cell transplantation

INTRODUCTION

Dental examination and stabilization are performed prior to allogeneic hematopoietic cell transplantation to decrease infection risk during neutropenia. Burden of dental disease and treatment need is not well characterized in this population.

OBJECTIVES

This report describes the dental status of a cohort of patients within the Chronic Graft-versus-Host Disease Consortium and treatment rendered prior to transplant.

METHODS

The cohort included 486 subjects (Fred Hutchinson: n = 245; Dana-Farber: n = 241). Both centers have institutional-based dental clearance programs. Data were retrospectively abstracted from medical records by calibrated oral health specialists.

RESULTS

The median age at transplant was 55.9 years, 62.1% were male, and 88% were white. Thirteen patients were edentulous (2.7%). The mean teeth among dentate patients before clearance was 26.0 (SD, 4.6). Dental findings included untreated caries (31.2%), restorations (91.6%), endodontically treated teeth (48.1%), and dental implants (5.7%). Pretransplant procedures during clearance included endodontic therapy (3.6%; mean = 0.1 teeth), restorations (25.1%; mean = 0.7), dental prophylaxis (59.2%), scaling/root planing (5.1%), and extraction (13.2%; mean = 0.3). The mean teeth after clearance was 25.6 (SD, 5.0).

CONCLUSIONS

Retrospective analysis of pre-AlloHCT dental data in subjects at two large transplant centers identified low levels of dental need. Findings suggest high access to care.

Dental status and risk of odontogenic complication in patients undergoing hematopoietic stem cell transplant

PURPOSE

Dental evaluation and management prior to hematopoietic stem cell transplant (HSCT) plays a vital role in identifying and treating infections that may be life-threatening. The purpose of this study is to describe the dental management of patients undergoing pre-HSCT examination with the Dental Service at Memorial Sloan Kettering Cancer Center (MSKCC) and to report on odontogenic complications.

METHODS

Patients referred for evaluation as part of the standard preparation for HSCT were included. Following clinical and radiological examination, patients were assigned to one of three groups based on risk of odontogenic infection, and treatment was provided as indicated. Patients were followed, and their medical records were reviewed for odontogenic complications during the transplant admission.

RESULTS

Of the 375 patients evaluated, 350 patients underwent HSCT: allogeneic 143 (40.9%) and autologous 207 (59.1%). The distribution of primary cancer diagnosis was as follows: multiple myeloma 104 (29.7%), leukemias 95 (27.1%), Hodgkin's lymphoma 28 (8.0%), non-Hodgkin's Lymphoma 99 (28.3%), and other conditions 24 (6.9%). The median time from dental evaluation to transplant was 29 days. The median Decayed, Missing, Filled Teeth Index was 17. The median Community Periodontal Index was 1. Based on dental status, 145 patients (41.4%) were classified as low risk, 133 (38%) as moderate risk and 72 (20.6%) as high risk of odontogenic infection. One hundred fourteen patients (32.6%) required dental treatment prior to HSCT, and 100 of these (28.6%) completed treatment. Two (0.57%) patients had odontogenic complications.

CONCLUSIONS

With conservative pre-HSCT dental treatment based on an infection risk classification system, a low odontogenic complication rate was observed.

Post-transplantation lymphoproliferative disorder after haematopoietic stem cell transplantation

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication of haematopoietic stem cell transplantation (HSCT), occurring in a setting of immune suppression and dysregulation. The disease is in most cases driven by the reactivation of the Epstein-Barr virus (EBV), which induces B cell proliferation through different pathomechanisms. Beyond EBV, many factors, variably dependent on HSCT-related immunosuppression, contribute to the disease development. PTLDs share several features with primary lymphomas, though clinical manifestations may be different, frequently depending on extranodal involvement. According to the WHO classification, histologic examination is required for diagnosis, allowing also to distinguish among PTLD subtypes. However, in cases of severe and abrupt presentation, a diagnosis based on a combination of imaging studies and EBV-load determination is accepted. Therapies include prophylactic and pre-emptive interventions, aimed at eradicating EBV proliferation before symptoms onset, and targeted treatments. Among them, rituximab has emerged as first-line option, possibly combined with a reduction of immunosuppression, while EBV-specific cytotoxic T lymphocytes are effective and safe alternatives. Though prognosis remains poor, survival has markedly improved following the adoption of the aforementioned treatments. The validation of innovative, combined approaches is the future challenge.

Characterization of Pneumocystis jirovecii pneumonia at three tertiary comprehensive hospitals in southern China

Due to the increasing use of immunosuppressant therapy, Pneumocystis jirovecii pneumonia (PJP) has become an emerging concern in human immunodeficiency virus (HIV)-negative patients. In this study, we conducted a retrospective study of 96 hospitalized patients with PJP from January 2015 to June 2019 at three tertiary comprehensive hospitals in Southern China. Information was collected regarding patient demographics, clinical manifestations, risk factors, laboratory analyses, radiological images, and treatment outcomes. PJP infection was most commonly found in middle-aged men. Kidney diseases (35.5%) and connective tissue diseases (38.7%) were the predominant risk factors for PJP. About half of the patients (48.4%) received glucocorticoid, immunosuppressant, and/or chemotherapy in a low dose or in a short-term (< 3 months). None of the patients had previously received trimethoprim-sulfamethoxazole (TMP-SMX) for PJP prophylaxis. All patients had two or more clinical manifestations (cough, dyspnea, fever, and chest pain). Biochemical investigations of CRP, ESR, PaO2, LDH, and KL-6 showed that over 90% of the patients exceeded the reference range of indicators. Our analyses revealed the dominant risk factors (HIV, kidney diseases, and connective tissue diseases) and the most consistent biochemical indicators (LDH, BG, and KL-6) for PJP. Moreover, early prophylaxis, diagnosis, and treatment should contribute to improve the survival of these PJP patients.

Risk of invasive fungal infections during hospital construction: how to minimize its impact in immunocompromised patients

PURPOSE OF REVIEW

Fungal outbreaks have been reported in healthcare settings, showing that construction activities are a serious threat to immunocompromised hosts. Preventive measures to control fungal outbreaks (especially Aspergillus spp.) are considered essential during hospital construction. In this article, we update the main advances in each of preventive strategies.

RECENT FINDINGS

Anticipation and multidisciplinary teamwork are the keystone for fungal outbreaks prevention. Strategies focused on environmental control measures of airborne dissemination of fungal spores have proven to be successful. It is important to recommend azole-resistant Aspergillus fumigatus active surveillance from both air (outdoors and indoors) and clinical samples during hospital construction works. Apart from genotyping, studies should be further encouraged to understand the environmental dynamics. Risk assessment and implement preventive measures (environment control strategies, air surveillance, inpatients immunocompromised patients in high-efficiency particulate air filters rooms, patient education, antifungal prophylaxis in high-risk patient groups, etc.) have shown that these accomplish to reduce the incidence of invasive fungal infection (IFI).

SUMMARY

In general, it is not only a strategy that should be implemented to reduce the risk of IFI but is a bundle of preventive measures, which have proven to be successful in control infection and prevention of airborne transmission of fungi.

Comparative effectiveness of antifungal agents in patients with hematopoietic stem cell transplantation: a systematic review and network meta-analysis

Purpose: The aim of this study was to use a network meta-analysis to evaluate the relative efficacy of various agents at preventing invasive fungal infections (IFIs). In this way, suitable prophylactic regimens may be selected for patients with hematopoietic stem cell transplantation (HSCT). Methods: We conducted a systematic review of randomized controlled trials comparing the prophylactic effects of two antifungal agents or an antifungal agent and a placebo administered to patients with HSCT. Relevant studies were found in the PubMed and Cochrane databases. Unpublished studies were collected from the ClinicalTrials.gov registry. Results: Sixteen two-arm studies were identified. Compared with placebo, all six antifungal agents (amphotericin B, fluconazole, itraconazole, micafungin, posaconazole, and voriconazole) presented with greater efficacy at controlling proven IFIs. OR ranged from 0.08 to 0.29. Voriconazole (surface under the cumulative ranking curve [SUCRA]=71.6%), posaconazole (SUCRA=68.9%), and itraconazole (SUCRA=64.7%) were the three top-ranking drugs for preventing proven IFIs. Itraconazole ranked highest (SUCRA=83.1%) and had the greatest efficacy at preventing invasive candidiasis. Posaconazole and micafungin were the two top-ranking drugs (SUCRA=81.3% and 78.4%, respectively) at preventing invasive aspergillosis. Micafungin and voriconazole were the drugs of choice because they lowered mortality more than the other agents (SUCRA=74.6% and 61.1%, respectively). Conclusion: This study is the first network meta-analysis to explore the prophylactic effects of antifungal agents in patients with HSCT. Voriconazole was the best choice for the prevention of proven IFIs in HSCT patients.

Cost-effectiveness of posaconazole tablets versus fluconazole as prophylaxis for invasive fungal diseases in patients with graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

BACKGROUND

The cost-effectiveness of posaconazole oral suspension versus fluconazole capsules for the prophylaxis of invasive fungal diseases (IFDs) in immunosuppressed allogeneic hematopoietic stem cell transplantation (HSCT) recipients has already been proven. Now, a new solid oral tablet formulation for posaconazole has been developed with improved bioavailability, allowing a reduced daily dosage that can be taken independently of food intake. However, the efficacy of this new formulation should be evaluated since it is associated with a higher cost than the posaconazole oral suspension.

OBJECTIVES

To evaluate the cost-effectiveness of solid oral tablets of posaconazole versus fluconazole capsules for the prophylaxis of IFDs in allogeneic HSCT recipients with graft-versus-host disease (GVHD) in Spain.

METHODOLOGY

A mathematical model comparing the efficacy and costs of posaconazole versus fluconazole was adapted to the Spanish National Healthcare System. Clinical data were obtained from the pivotal clinical trial of posaconazole oral suspension for allogeneic HSCT recipients, while pharmacological costs and use of resources were obtained from national sources. Deterministic and probabilistic sensitivity analyses (PSA), as well as two alternative scenarios, were run to evaluate the robustness of the results under varying input values.

RESULTS

Posaconazole tablets reduced the number of IFD events and enhanced overall survival, while maintaining a controlled budget. When compared to fluconazole, it was found to be a cost-effective alternative, with an incremental cost-effectiveness ratio of €13,193/life years gained. The PSA showed that posaconazole remained cost-effective in 74.6% of the cases, while alternatives scenarios yielded similar results as the base case.

CONCLUSIONS

Posaconazole tablets are a cost-effective alternative to fluconazole and may show better results than the oral suspension formulation.

Invasive aspergillosis in neutropenic patients during hospital renovation: effectiveness of mechanical preventive measures in a prospective cohort of 438 patients

BACKGROUND

Aspergillus species are the main cause of invasive fungal disease for patients with severe and prolonged neutropenia. Building or renovation works have been shown as one of the major causes of outbreaks of aspergillosis.

OBJECTIVES

This study aimed to assess the effectiveness of introduction and adaptation by air sampling of mechanical preventive measures on the incidence of invasive pulmonary aspergillosis in neutropenic patients during hospital renovation.

PATIENTS

All of the patients admitted for prolonged and severe neutropenia during a renovation period from 2003 to 2008 were prospectively enrolled. Invasive pulmonary aspergillosis (IPA) cases were classified as possible, probable, and proven, according to the 2008 European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group criteria. The effectiveness of preventive measures was determined by air sampling.

RESULTS

We recorded 705 hospitalizations for neutropenia concerning 438 patients. The majority of hospitalized neutropenic patients was treated for acute leukemia (38.3 %), followed by patients suffering from non-Hodgkin and Hodgkin lymphomas (33 %). The total cumulative incidence of probable and proven IPA was 4.1 %. Risk factors for developing IPA were underlying disease, treatment course at the time of hospitalization, and the mean duration of hospitalization and of neutropenia.

CONCLUSIONS

In this prospective study, the incidence of invasive pulmonary aspergillosis did not increase in neutropenic patients during a renovation period because of efficient mechanical preventive measures systematically adjusted using the results of air sampling.

Invasive pneumococcal disease following adult allogeneic hematopoietic stem cell transplantation

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (alloHSCT) recipients are at high risk of invasive pneumococcal disease (IPD). We investigated the incidence and risk factors of IPD in alloHSCT recipients from 4 regional transplant centers over an 11-year period. This study aimed to inform future improvements in post-transplant care.

METHODS

We conducted a retrospective nested 1:2 case-control study in patients aged ≥18 years who underwent alloHSCT between 2001 and 2011 in 4 major allogeneic transplant centers. Controls were matched with IPD cases on the basis of conditioning intensity and donor relationship (related or unrelated). Demographics and clinical characteristics of cases and controls were summarized. Univariate analysis of risk factors in matched case-control sets, and multivariate conditional logistic regression to control for confounding, were performed.

RESULTS

In 23 alloHSCT recipients, 26 IPD episodes were identified. The cumulative incidence over 11 years was 2.3% (95% confidence interval [CI] 1.45-3.15) and the incidence density 956 per 100,000 transplant years of follow-up (95% CI 580-1321). Multivariate risk factor analysis and backwards elimination showed a significant positive association between mycophenolate mofetil (MMF), hyposplenism/asplenia, and IPD, whereas trimethoprim-sulfamethoxazole (TMP/SMX) prophylaxis for Pneumocystis jirovecii pneumonia (PJP) was associated with lower odds of IPD cases. Of alloHSCT recipients with IPD, 38.5% required intensive care, and, of deaths documented in cases over the period of review, 30% were attributable to IPD. Serotypes causing IPD matched currently available vaccines in 15/22 (68.1%) episodes.

CONCLUSIONS

The incidence of IPD in alloHSCT recipients is an important cause of morbidity and mortality, with rates of disease being many fold higher than the general population. Patients with evidence of hyposplenism/asplenia define a high-risk group in the alloHSCT population for IPD, and the independent association with IPD and MMF in the adjusted model from this study requires further evaluation. The occurrence of post-transplant IPD may be reduced by measures such as vaccination with both 13-valent and 23-valent pneumococcal vaccines. TMP/SMX prophylaxis for the prevention of PJP may offer incidental protection against IPD in alloHSCT recipients.

Dietary recommendations for immunosuppressed patients of 17 hematopoietic stem cell transplantation centers in Brazil

Introduction

Low-microbial diets are recommended to reduce the risk of foodborne infections when hematopoietic stem cell transplantation patients have neutropenia. However there is no pattern concerning the composition of such a diet.

Objective

To collect information concerning the structure of nutrition departments and the diets recommended for immunosuppressed patients in transplant centers in Brazil.

Methods

Questionnaires were sent to the 45 Bone Marrow Transplantation Centers listed by the Sociedade Brasileira de Transplante de Medula Óssea (SBTMO). Completed questionnaires were returned by 17 centers. The questions were related to the profile and the structure of the nutrition department, at what point a general diet is allowed after transplantation, and which food is allowed during the critical period of immunosuppression and soon after transplantation.

Results

Of the 17 centers that participated, 82% have a professional nutritionist exclusively for the Transplant Department but only 41% have an area specifically for the preparation of diets for immunosuppressed patients. The patients are released from the low-microbial diet to general diets 90-100 days after allogeneic hematopoietic stem cell transplantation by 29% of the centers and only after suspension of immunosuppressive drugs in 24%. Most centers (88%) restrict the consumption of raw fruits, all restrict the consumption of raw vegetables and 88% forbid the consumption of yogurt in the critical period of immunosuppression. There was no consensus on forbidden foods soon after transplantation.

Conclusion

Major differences in diets recommended to hematopoietic stem cell transplantation patients were observed between the different centers.

X-ray irradiation selectively kills thymocytes of different stages and impairs the maturation of donor-derived CD4(+)CD8(+) thymocytes in recipient thymus

The aim of the present study was to determine whether the sensitivity of thymocytes to X-ray radiation depends on their proliferative states and whether radiation impairs the maturation of donor-derived thymocytes in recipient thymus. We assigned 8-week-old C57BL/6J mice into three treatment groups: 1) untreated; 2) X-ray radiation; 3) X-ray radiation plus bone marrow transplantation with donor bone marrow cells from transgenic mice expressing enhanced green fluorescent protein (GFP) on a universal promoter. After 4 weeks, the size of the thymus, the number and proliferation of thymocytes and ratios of different stage thymocytes were analyzed by immunohistochemistry and flow cytometry. The results showed that: 1) CD4(+)CD8(+) thymocytes were more sensitive to X-ray radiation-induced cell death than other thymocytes; 2) the proliferative capacity of CD4(+)CD8(+) thymocytes was higher than that of other thymocytes; 3) the size of the thymus, the number of thymocytes and ratios of thymocytes of different stages in irradiated mice recovered to the normal level of untreated mice by bone marrow transplantation; 4) the ratio of GFP-positive CD4(+)CD8(+) thymocytes increased significantly, whereas the ratio of GFP-positive CD4(+) or CD8(+) thymocytes decreased significantly. These results indicate that the degree of sensitivity of thymocytes to X-ray radiation depends on their proliferative states and radiation impairs the maturation of donor-derived CD4(+)CD8(+) thymocytes in recipient thymus.

Routine surveillance for bloodstream infections in a pediatric hematopoietic stem cell transplant cohort: Do patients benefit?

BACKGROUND

Hematopoietic stem cell transplant (HSCT) recipients are at a high risk for late bloodstream infection (BSI). Controversy exists regarding the benefit of surveillance blood cultures in this immunosuppressed population. Despite the common use of this practice, the practical value is not well established in non-neutropenic children following HSCT.

METHODS

At the IWK Health Centre (Halifax, Nova Scotia), weekly surveillance blood cultures from central lines are drawn from children following HSCT until the line is removed. A retrospective chart review was performed to determine the utility and cost of this practice. Eligible participants were non-neutropenic HSCT recipients with central venous access lines. The cost of laboratory investigations, nursing time, hospital stay and interventions for positive surveillance cultures was calculated.

RESULTS

Forty-three HSCTs were performed in 41 children. Donors were allogenic in 33 cases (77%) and autologous in 10 cases (23%). There were 316 patient contacts for surveillance cultures (mean seven per patient) and 577 central line lumens sampled. Three of 43 patients (7%) had clinically significant positive surveillance blood cultures. Bacteria isolated were Klebsiella pneumoniae (n=2) and Corynebacterium jeikeium (n=1). All follow-up cultures before initiation of antimicrobial therapy were sterile. All three patients were admitted for antimicrobial therapy if they were not already hospitalized and/or had an uncomplicated course. The estimated total cost of BSI surveillance and management of asymptomatic infection over six years was $27,989.

CONCLUSION

The present study suggests that BSI surveillance in children following HSCT engraftment has a very low yield and significant cost. It is unclear whether it contributes to improved patient outcomes.

Immunization in the adult immunocompromised host

The number of patients with impaired immune response has been steadily increasing within the last years, not only with the onset of the AIDS epidemic, but also due to increasing numbers of subjects on immunosuppressive therapies. These patients are at an increased risk for infections, many of which are preventable by immunization. Inactivated vaccines are generally safe in subjects with underlying immunosuppression. However, immune response and protection may be hampered, depending on the extent of immunosuppression. In contrast, live vaccines such as yellow fever, measles, rubella, herpes zoster, and cholera may lead to severe reactions in immunocompromised patients and have been shown to deteriorate some immune-mediated diseases such as multiple sclerosis. Data on the efficacy of vaccines in biological therapies is scarce. Where necessary vaccines should be updated before immunosuppressive therapies are started. To improve the vaccination status several guidelines exist for immunosuppressed patients at risk such as those with rheumatic diseases, asplenia or solid organ and hematopoietic stem cell transplantation.

Oral care in Brazilian bone marrow transplant centers

Background

Oral care is a fundamental procedure for the success of the hematopoietic stem cell transplantation, particularly regarding the control of oral infectious diseases. Information about oral care protocols and the inclusion of dental professionals in transplantation medical staff is poorly known.

Objective

The aim of this study was to carry out a survey about the protocols of Brazilian dental professionals with regard to oral care of HSCT patients.

Methods

A questionnaire was mailed to 36 Brazilian transplant centers with questions about basic oral care protocols, the indication of specific mouthwashes, antibiotic therapy regimens, laser therapy, and treatment of oral mucositis and graft-versus-host disease. All the respondent centers (n = 12) have dentists as members of the HSCT medical staff.

Results

The majority indicate non-alcoholic chlorhexidine (n = 9; 75.0%) and sodium bicarbonate (n = 5; 41.7%) as routine mouthwashes. Laser therapy was frequently indicated (n= 9; 75.0%), mainly in the prevention of oral mucositis and in oral pain control. In the post-transplant period, antibiotic therapy was only indicated for invasive dental treatments (n= 8; 66.7%). Several treatments for graft-versus-host disease were mentioned without a trend towards establishing a standard protocol.

Conclusion

Basic oral care constitutes regular assessment in the routine treatment of hematopoietic stem cell transplantation patients in Brazilian centers.

Retrospective evaluation of the area over the neutrophil curve index to predict early infection in hematopoietic stem cell transplantation recipients

We investigated the impact of neutropenia on the development of early bloodstream and pulmonary infections in hematopoietic stem cell transplantation (HSCT) recipients, and evaluated the utility of an index (D-index) that reflects both the intensity and duration of neutropenia. Fifty-eight patients (23 autologous, 35 allogeneic HSCT recipients) were enrolled in this retrospective study. The D-index was defined as the area over the neutrophil curve during neutropenia. We also evaluated the utility of the cumulative D-index from the start of neutropenia until the development of infection (c-D-index), which may enable real-time assessment of the risk for infection. The patients showed 12 and 7 episodes of bloodstream and pulmonary infection, respectively. The D-index, days of neutropenia (<500/microL) and days of profound neutropenia (<100/microL) had at least a nearly significant impact on the development of both bloodstream and pulmonary infections. On the other hand, the c-D-index, cumulative days of neutropenia, and cumulative days of profound neutropenia significantly affected pulmonary infection, but not bloodstream infection. The c-D-index had a high negative predictive value of 97.4% for pulmonary infection with a cutoff of 5500, but the area under the receiver operating characteristic curve was similar to that of the cumulative days of neutropenia and profound neutropenia. Our results showed that although the c-D-index may be useful for identifying patients who are at low risk for early pulmonary infection after HSCT, its performance was similar to that of the simple duration of neutropenia.

Medical cost analysis for antifungal prophylaxis in neutropenic patients with hematological malignancies: a systematic simulation analysis

GOALS OF WORK

We assessed the medical costs of different antifungal agents for prophylaxis of invasive fungal infections in neutropenic patients in Japan with a cost simulation model designed for the study.

PATIENTS AND METHODS

We used probabilities of prophylaxis failure, possible cases for empiric therapy, probable proportions of infections caused by fungus species among prophylaxis failure patients, and incidence of adverse events caused by any reason, based on systematic analysis of previously reported randomized trials identified by a computerized search of the PubMed database. Antifungal agents were limited to oral fluconazole, oral itraconazole, micafungin, and liposomal amphotericin B. The range of the expected medical cost was simulated as a sensitivity analysis using 95% of confidence interval of a mean.

MAIN RESULTS

Fifteen studies were identified for our analysis. The prophylactic efficacy was comparable between the four agents. The simulated expected cost for invasive fungal infection prophylaxis and treatment of the infection was $1,035.74 when oral itraconazole was used for prophylaxis, $1,552.81 with oral fluconazole, $2,245.96 with micafungin, and $3,028.10 with liposomal amphotericin B. The total cost including treatment cost for adverse events related to each drug was $2,742.14, $3,547.91, $3,034.57, and $3,028.10, respectively. This result was confirmed in a sensitivity analysis in which IFI incidence and therapy duration were tested as parameters.

CONCLUSIONS

Our analysis results suggest that oral itraconazole is the most cost-effective prophylactic antifungal agent for invasive fungal infections in neutropenic patients with hematological malignancies, and this result was robust by sensitivity analysis.

Best practice recommendations for the selection and management of patients with multiple sclerosis receiving natalizumab therapy

Natalizumab, a humanized monoclonal antibody directed against α4-integrin is a first-in-class disease-modifying therapy for the treatment of relapsing multiple sclerosis. Natalizumab is highly effective but has been associated with a risk of progressive multifocal leukoencephalopathy. Since the efficacy of natalizumab in relapsing forms of multiple sclerosis is viewed as superior to first-line agents, a growing number of neurologists are using natalizumab as the treatment of choice for patients with worsening MS. Owing to the recently reported cases of progressive multifocal leukoencephalopathy, a panel of neurologists met in February 2009 to discuss best practices for the use of natalizumab, with the goal of developing consensus-based recommendations on patient management to minimize the risk of progressive multifocal leukoencephalopathy. The panel consisted of a cross section of academic and community neurologists from the United States who treat multiple sclerosis in large centers and have extensive experience with natalizumab (approximating 2000 patient-years combined experience). This paper summarizes the panel's recommendations on the following: (1) appropriate patient selection for natalizumab; (2) routine monitoring and management of adverse events during natalizumab therapy; and (3) clinical vigilance monitoring and risk reduction for progressive multifocal leukoencephalopathy.

Impact of a silver layer on the membrane of tap water filters on the microbiological quality of filtered water

Background

Bacteria in the hospital's drinking water system represent a risk for the acquisition of a nosocomial infection in the severely immunocompromised host. Terminal tap water filters may be used to prevent nosocomial Legionnaires' disease. We present data from water samples using an improved kind of tap water filters.

Methods

In a blinded study on an intermediate care unit of the thoracic surgery department, a modified type of the Germlyser water filter (Aqua-Free Membrane Technology) with a newly-introduced silver layer on the filtration membrane was compared to its preceding type without such a layer on 15 water outlets. We determined growth of Legionella, other pathogenic bacteria, and the total heterotrophic plate count in unfiltered water and filtered water samples after filter usage intervals of 1 through 4 weeks.

Results

A total of 299 water samples were tested. Twenty-nine of the 60 unfiltered water samples contained Legionella of various serogroups (baseline value). In contrast, all samples filtered by the original water filter and all but one of the water samples filtered by the modified filter type remained Legionella-free. No other pathogenic bacteria were detected in any filtered sample. The total plate count in water samples increased during use of both kinds of filters over time. However, for the first 7 days of use, there were significantly fewer water samples containing >100 CFU per mL when using the new filter device compared with the older filters or taps with no filter. No advantage was seen thereafter.

Conclusion

The use of this type of terminal water filter is an appropriate method to protect immunocompromised patients from water-borne pathogens such as Legionella.

Transmission of tropical and geographically restricted infections during solid-organ transplantation

In recent years, the increasing number of donors from different regions of the world is providing a new challenge for the management and selection of suitable donors. This is a worldwide problem in most countries with transplantation programs, especially due to the increase in immigration and international travel. This paper elaborates recommendations regarding the selection criteria for donors from foreign countries who could potentially transmit tropical or geographically restricted infections to solid-organ transplant recipients. For this purpose, an extensive review of the medical literature focusing on viral, fungal, and parasitic infections that could be transmitted during transplantation from donors who have lived or traveled in countries where these infections are endemic has been performed, with special emphasis on tropical and imported infections. The review also includes cases described in the literature as well as risks of transmission during transplantation, microbiological tests available, and recommendations for each infection. A table listing different infectious agents with their geographic distributions and specific recommendations is included.

Antifungal Prophylaxis in Cancer Patients After Chemotherapy or Hematopoietic Stem-Cell Transplantation: Systematic Review and Meta-Analysis

Purpose

To evaluate the effect of antifungal prophylaxis on all-cause mortality as primary outcome, invasive fungal infections (IFIs), and adverse events. Many studies have evaluated the role of antifungal prophylaxis in cancer patients, with inconsistent conclusions.

Methods

We performed a systematic review and meta-analysis of randomized, controlled trials comparing systemic antifungals with placebo, no intervention, or other antifungal agents for prophylaxis in cancer patients after chemotherapy. The Cochrane Library, MEDLINE, conference proceedings, and references were searched. Two reviewers independently appraised the quality of trials and extracted data.

Results

Sixty-four trials met inclusion criteria. Antifungal prophylaxis decreased all-cause mortality significantly at end of follow-up compared with placebo, no treatment, or nonsystemic antifungals (relative risk [RR], 0.84; 95% CI, 0.74 to 0.95). In allogeneic hematopoietic stem-cell transplantation (HSCT) recipients, prophylaxis reduced all-cause mortality (RR, 0.62; 95% CI, 0.45 to 0.85), fungal-related mortality, and documented IFI. In acute leukemia patients, there was a significant reduction in fungal-related mortality and documented IFI, whereas the difference in mortality was only borderline significant (RR, 0.88; 95% CI, 0.74 to 1.06). Prophylaxis with itraconazole suspension reduced documented IFI when compared with fluconazole, with no difference in survival, and at the cost of more adverse events. On the basis of two studies, posaconazole prophylaxis reduced all-cause mortality (RR, 0.74; 95% CI, 0.56 to 0.98), fungal-related mortality, and IFI when compared with fluconazole.

Conclusion

Antifungal prophylaxis decreases all-cause mortality significantly in patients after chemotherapy. Antifungal prophylaxis should be administered to patients undergoing allogeneic HSCT, and should probably be administered to high-risk acute leukemia patients.

Establishment of a pediatric HSCT program in a public hospital in Chile

BACKGROUND

In Chile, survival estimates for pediatric patients with cancer are comparable to those in the United States and Western Europe. Approximately 80% of these patients are treated at government-supported centers, and an estimated 65% are cured. We reasoned that cure rates could be further improved if transplantation with hematopoietic stem cells were available for patients with chemotherapy-resistant malignancy.

PATIENTS AND METHODS

Physicians and nurses were selected to be trained in international centers, and a transplantation unit was developed at Luis Calvo Mackenna Hospital in Santiago. Between October 1999 and December 2003, 59 patients received transplants. Of these, 42 were from HLA-matched family members and 11 were autologous.

RESULTS

The 3-year event-free survival estimate was 72 +/- 10% overall, and it was 81 +/- 10% for the subgroup treated with matched related transplants. Peritransplant mortality was 6.6%. The average cost for an allogeneic transplant in our unit was 50,000 US dollars.

CONCLUSIONS

We are encouraged by this experience as well as by the overall survival rates and hope to expand the program. Our goal is to extend treatment to all children in the country for whom HSCT is indicated, including those who do not have HLA-identical family donors.

Reactivation of resolved hepatitis B virus infection after allogeneic haematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10(2)-10(3) copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.

Eradication of invasive mucormycosis--effectiveness of the Echinocandin FK463

BACKGROUND

Invasive rhinocerebral mucormycosis is a rare and often fatal opportunistic fungal infection. It is encountered in immunocompromised hosts exemplified by those with diabetes, human immunodeficiency viruses and particularly haematologic malignancies typically after high-dose chemotherapy and stem cell transplantation. In contrast to the more usual outcome with rapid progression and death. We now describe a successful eradication attributable to the use of a newly available antifungal agent.

SETTING

Haematology department and bone marrow transplantation unit.

MATERIAL AND METHOD

Two patients are contrasted. The first with acute leukaemia developed rapidly progressive facial swelling with mucormycosis proven on biopsy. Treatment over 2 months with maximally tolerated doses of amphotericin failed to halt intracranial extension and death resulted. The second, presented with acute lymphoblastic leukaemia in August 1997, underwent successful autologous bone marrow transplantation in February 1998. Relapse followed in March 1999 and after reinduction and consolidation receive a matched unrelated volunteer allograft in September 1999. A second recurrence was documented in April 2000 and in spite of achieving remission he developed a fever that was managed empirically with intravenous amphotericin and, on discharge, oral itraconazole. Left-sided facial swelling expanded rapidly and biopsy showed extensive invasion of the maxillary sinus with mucormycosis. FK463 was added on 5 June 2000 with gradual reduction in facial pain and within 1 month all clinical signs and resolved. Serial biopsies that included histopathologic investigation and microbiologic cultures confirmed eradication of the invasive mucor. In view of the potential danger of recrudescence this treatment regimen was continued through further chemotherapy and, once again disease-free, a second matched unrelated volunteer allograft took place in August 2000. Full reassessment at the time failed to demonstration any residual fungus. Engraftment was confirmed but neutropenic sepsis resulted in severe inflammatory response syndrome with progression to multiple organ dysfunction to which he succumbed without any evidence of leukaemic or systemic mycosis.

CONCLUSION

Echinocandin FK463 is of documented value in managing invasive candidiasis and aspergillosis. This is believed to be the first case of successful outcome with one of the angiotrophic zygomycetes.