Prophylactic and interventional granulocyte transfusions in patients with haematological malignancies and life-threatening infections during neutropenia

Anorectal Infections in Neutropenic Leukemia Patients: A Common Clinical Challenge

Anorectal infections in neutropenic leukemia patients are a significant and potentially life-threatening complication. The pathogenesis of this condition is not entirely understood and believed to be multifactorial, including mucosal injury as a result of cytotoxic drugs, profound neutropenia and impaired host defense. Establishing an early diagnosis is key and often made clinically on the basis of signs and symptoms, but also from imaging studies demonstrating perianal inflammation or fluid collection. The management of anorectal infections in neutropenic leukemia patients is not straightforward, as there are no well-conducted studies on this entity. This review seeks to provide a framework into the pathophysiology and clinical presentation of anorectal infections in neutropenic leukemia patients, propose a diagnostic approach and to discuss controversies in the management of this condition.

Comparison of two apheresis systems for granulocyte collection without hydroxyethyl starch

BACKGROUND AND OBJECTIVES

Granulocyte transfusion (GTX) is a treatment option for severe infections in patients with neutropenia. In previous studies, hydroxyethyl starch (HES) was used to enhance red blood cell sedimentation for granulocyte collection (GC). However, there are safety concerns about HES, and HES is not readily available in some countries. Therefore, we compared the granulocyte counts and GC efficiency achieved by two apheresis systems without HES.

MATERIALS AND METHODS

All consecutive GC procedures performed between July 2011 and March 2018 at our hospital were analysed. COBE Spectra was used until 5 February 2016, and Spectra Optia was used afterwards. HES was not used.

RESULTS

Twenty-six GC procedures were performed, including 18 performed using COBE Spectra and 8 using Spectra Optia. When Spectra Optia was used, >1 × 1010 neutrophils were collected from seven of the eight (88%) procedures. Although there was no significant difference in the granulocyte yield between COBE Spectra-based and Spectra Optia-based GC procedures, the collection efficiency of Spectra Optia was significantly higher than that of COBE Spectra (p = 0.021). Furthermore, the granulocyte yields of Spectra Optia-based GC tended to be more strongly correlated with the peripheral blood neutrophil count on the day of apheresis than those of COBE Spectra-based GC.

CONCLUSION

Our results suggest that Spectra Optia achieves greater GC efficiency than COBE Spectra, even without HES. GTX may be a therapeutic option for severe neutropenia, even in places where HES is not available.

Novel Approaches in the Management of Mucormycosis

Purpose of Review

Invasive mucormycosis (IM), caused by fungi of the order Mucorales, is one of the deadliest fungal infection among hematologic cancer patients. Its incidence is also increasingly reported in immunocompetent individuals, notably with the COVID-19 pandemic. Therefore, there is an urgent need for novel diagnostic and therapeutic approaches of IM. This review discusses the current advances in this field.

Recent Findings

Early diagnosis of IM is crucial and can be improved by Mucorales-specific PCR and development of lateral-flow immunoassays for specific antigen detection. The spore coat proteins (CotH) are essential for virulence of the Mucorales and may represent a target for novel antifungal therapies. Adjuvant therapies boosting the immune response, such as interferon-γ, anti-PDR1 or fungal-specific chimeric antigen receptor (CAR) T-cells, are also considered.

Summary

The most promising perspectives for improved management of IM consist of a multilayered approach targeting both the pathogen and the host immune system.

Case report: A Saprochaete clavata (Magnusiomyces clavatus) severe infection effectively treated with granulocyte transfusion in a young patient with myeloid sarcoma

Myeloid sarcoma is a hematologic malignancy consisting of extramedullary tissue involvement by myeloid blasts, usually considered as acute myeloid leukemia and treated accordingly. The disease itself, together with chemotherapy and disease-associated factors, may have an impact in increasing the risk of developing severe and frequently life-threatening infections. Herein, we describe the case of a patient with a right breast skin lesion, histologically diagnosed myeloid sarcoma, who developed a severe disseminated fungal infection by Saprochaete clavata (Magnusiomyces clavatus), during the first consolidation course of chemotherapy. Despite maximum antifungal therapy, the infection progressed and the fungus continued to be isolated until granulocyte transfusion therapy was initiated. Our experience suggests that patients with profound and long-lasting neutropenia could benefit from granulocyte transfusions as additional therapy in severe fungal infections resistant to broad-spectrum antimicrobial therapy.

ABO-incompatible granulocyte transfusion: Is ABO subgroup a barrier?

Granulocyte transfusion (GTx) is an efficient and compelling treatment option for patients with neutropenia following hematopoietic stem cell transplant. The donor pool for granulocyte harvest is limited to close friends and family members and the donors accepted are often of the same ABO Rh type. We report a case of ABO-incompatible prophylactic GTx, in a case of acute myeloblastic leukemia. Postcollection processing of the granulocyte product was done to reduce the red blood cell volume to <5 ml, making it safe for transfusion. The transfusion was successful in stabilizing the total leukocyte counts in the patient. The patient was monitored, and there were no adverse reactions posttransfusion.

[Mucormycosis: Current and future management perspective]

Infections caused by mucorales, with an increasing incidence after candidiasis and aspergillosis, are characterized by the fast angioinvasion of blood vessels and invasion of neighboring organs or structures. Mucorales most commonly cause rhinocerebral, pulmonary, cutaneous, digestive or disseminated infections, and their spread is favored by certain underlying diseases (diabetes, kidney failure) and risk factors (neutropenia, immunosuppression, iron overload). These infections have a high mortality rate, over 40% in many series, and the key to their cure depends on both an early diagnosis and an antifungal treatment, associated in most cases with extensive surgical debridement and other adjunctive therapies. Currently, there are international guidelines, not only local ones, for the management of mucormycosis, in which it is considered by consensus and with a strong recommendation that first-line treatment with high-dose liposomal amphotericin B is the best choice. The combined antifungal treatment of polyene agents with triazoles or candins remains in open debate.

Use of granulocyte transfusion in early period in life-threatening infections of pediatric hematology and oncology patients: A single-center experience

Despite all the developments in medicine, infections continue to be one of the most important causes of mortality in pediatric hematology and oncology patients. The more severe the degree of neutropenia develops after intensive chemotherapy in cancer patients, and the longer the neutropenia duration, the higher the risk of infection. Granulocyte transfusion (GT) is used as supportive therapy in cases where the bone marrow needs time to recover in invasive bacterial or fungal infections along with severe neutropenia. The patients who had granulocyte transfusions in our clinic between June 2019 and June 2020 were reviewed retrospectively. A total of 15 units of granulocyte concentrate were used in 11 febrile neutropenia attacks of 9 patients. The demographic characteristics of the patients and features belonging to the period of GT were recorded. In our study, the clinical response rate after GT was 90.9 %, while the hematological response rate was 40 %. Most of the patients were treated succesfully, the mortality rate was 9%. We think that the most critical factor for success with GTs is determining the neutropenic patient in particular with a combination of high-risk malignancy and acute life-threatening infection for using GT. Also, early use of GT in those patients who do not recover despite appropriate antimicrobial and supportive treatment may contribute to improvement of the clinical conditon in a shorter period of time and reduction of repeated GTs.

How I perform hematopoietic stem cell transplantation on patients with a history of invasive fungal disease

Hematopoietic transplantation is the preferred treatment for many patients with hematologic malignancies. Some patients may develop invasive fungal diseases (IFDs) during initial chemotherapy, which need to be considered when assessing patients for transplantation and treatment posttransplantation. Given the associated high risk of relapse and mortality in the post-hematopoietic stem cell transplantation (HSCT) period, IFDs, especially invasive mold diseases, were historically considered a contraindication for HSCT. Over the last 3 decades, advances in antifungal drugs and early diagnosis have improved IFD outcomes, and HSCT in patients with a recent IFD has become increasingly common. However, an organized approach for performing transplantation in patients with a prior IFD is scarce, and decisions are highly individualized. Patient-, malignancy-, transplantation procedure-, antifungal treatment-, and fungus-specific issues affect the risk of IFD relapse. Effective surveillance to detect IFD relapse post-HSCT and careful drug selection for antifungal prophylaxis are of paramount importance. Antifungal drugs have their own toxicities and interact with immunosuppressive drugs such as calcineurin inhibitors. Immune adjunct cytokine or cellular therapy and surgery can be considered in selected cases. In this review, we critically evaluate these factors and provide guidance for the complex decision making involved in the peri-HSCT management of these patients.

Treatment of invasive fungal diseases in cancer patients-Revised 2019 Recommendations of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO)

BACKGROUND

Invasive fungal diseases remain a major cause of morbidity and mortality in cancer patients undergoing intensive cytotoxic therapy. The choice of the most appropriate antifungal treatment (AFT) depends on the fungal species suspected or identified, the patient's risk factors (eg length and depth of granulocytopenia) and the expected side effects.

OBJECTIVES

Since the last edition of recommendations for 'Treatment of invasive fungal infections in cancer patients' of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) in 2013, treatment strategies were gradually moving away from solely empirical therapy of presumed or possible invasive fungal diseases (IFDs) towards pre-emptive therapy of probable IFD.

METHODS

The guideline was prepared by German clinical experts for infections in cancer patients in a stepwise consensus process. MEDLINE was systematically searched for English-language publications from January 1975 up to September 2019 using the key terms such as 'invasive fungal infection' and/or 'invasive fungal disease' and at least one of the following: antifungal agents, cancer, haematological malignancy, antifungal therapy, neutropenia, granulocytopenia, mycoses, aspergillosis, candidosis and mucormycosis.

RESULTS

AFT of IFDs in cancer patients may include not only antifungal agents but also non-pharmacologic treatment. In addition, the armamentarium of antifungals for treatment of IFDs has been broadened (eg licensing of isavuconazole). Additional antifungals are currently under investigation or in clinical trials.

CONCLUSIONS

Here, updated recommendations for the treatment of proven or probable IFDs are given. All recommendations including the levels of evidence are summarised in tables to give the reader rapid access to key information.

Therapeutic Challenges of Non-Aspergillus Invasive Mold Infections in Immunosuppressed Patients

While Aspergillus spp. remain the major cause of invasive mold infections in hematologic cancer patients and transplant recipients, other opportunistic molds, such as Mucorales, Fusarium, and Scedosporium spp. are increasingly encountered in an expanding population of patients with severe and prolonged immunosuppression. High potential for tissue invasion and dissemination, resistance to multiple antifungals and high mortality rates are hallmarks of these non-Aspergillus invasive mold infections (NAIMIs). Assessment of drug efficacy is particularly difficult in the complex treatment scenarios of NAIMIs. Specifically, correlation between in vitro susceptibility and in vivo responses to antifungals is hard to assess, in view of the multiple, frequently interrelated factors influencing outcomes, such as pharmacokinetic/pharmacodynamic parameters determining drug availability at the site of infection, the net state of immune suppression, delay in diagnosis, or surgical debulking of infectious foci. Our current therapeutic approach of NAIMIs should evolve toward a better integration of the dynamic interactions between the pathogen, the drug and the host. Innovative concepts of experimental research may consist in manipulating the host immune system to induce a specific antifungal response or targeted drug delivery. In this review, we discuss the challenges in the management of NAIMIs and provide an update about the latest advances in diagnostic and therapeutic approaches.

Role of granulocyte transfusions in combating life-threatening infections in patients with severe neutropenia: Experience from a tertiary care centre in North India

Bacterial and fungal infections still remain an important cause of mortality in patients with hematological malignancies and in recipients of hematopoietic stem cell transplants (HSCT) especially in developing countries like India. Granulocyte transfusions (GTX) from healthy donors may lead to early clearance of index infection and thus prevent mortality. The aim of the present study was to evaluate the efficacy of GTX in combating life-threatening infections and preventing mortality in patients of hematological disorders/recipients of HSCT with severe neutropenia. This study was a prospective, observational analysis of patients with different hematological disorders/recipients of HSCT, who received GTX from January 2014 to December 2017. All patients had an Absolute neutrophil Count (ANC) < 0.5 x 109/L and a life threatening sepsis defined by presence of hemodynamic instability/ impending septic shock/ continuous high fever despite the use of the highest line of antimicrobials. A total of 143 granulocyte collections were done for 66 infectious episodes (IEs) in 60 patients. Multidrug resistant organisms (MDROs) were observed in 47/66 IEs (71.2%) and fungal infections were seen in 9/66 IEs (13.6%). Resolution of index infection after GTX was seen in 45/66 IEs (68.2%), and the 30 day overall survival (OS) was 67.7%. OS was significantly higher in patients who received GTX within 7 days of neutropenic sepsis (p = 0.01). Patients with MDROs who received early GTX therapy had a better OS as compared to those who received late GTX (p = 0.02). GTX were well tolerated and only 6 patients' developed mild features of transfusion related acute lung injury (TRALI) which was managed conservatively, and 1 patient demonstrated hypocalcemic tetany. GTX may be of particular relevance in countries like India, where the incidence of infections is very high in neutropenic patients and there is an increasing emergence of MDROs.

Immunomodulation as a Therapy for Aspergillus Infection: Current Status and Future Perspectives

Invasive aspergillosis (IA) is the most serious life-threatening infectious complication of intensive remission induction chemotherapy and allogeneic stem cell transplantation in patients with a variety of hematological malignancies. Aspergillus fumigatus is the most commonly isolated species from cases of IA. Despite the various improvements that have been made with preventative strategies and the development of antifungal drugs, there is an urgent need for new therapeutic approaches that focus on strategies to boost the host’s immune response, since immunological recovery is recognized as being the major determinant of the outcome of IA. Here, we aim to summarize current knowledge about a broad variety of immunotherapeutic approaches against IA, including therapies based on the transfer of distinct immune cell populations, and the administration of cytokines and antibodies.

Natural killer cells as a therapeutic tool for infectious diseases - current status and future perspectives

Natural Killer (NK) cells are involved in the host immune response against infections due to viral, bacterial and fungal pathogens, all of which are a significant cause of morbidity and mortality in immunocompromised patients. Since the recovery of the immune system has a major impact on the outcome of an infectious complication, there is major interest in strengthening the host response in immunocompromised patients, either by using cytokines or growth factors or by adoptive cellular therapies transfusing immune cells such as granulocytes or pathogen-specific T-cells. To date, relatively little is known about the potential of adoptively transferring NK cells in immunocompromised patients with infectious complications, although the anti-cancer property of NK cells is already being investigated in the clinical setting. This review will focus on the antimicrobial properties of NK cells and the current standing and future perspectives of generating and using NK cells as immunotherapy in patients with infectious complications, an approach which is promising and might have an important clinical impact in the future.

Methods of Controlling Invasive Fungal Infections Using CD8+ T Cells

Invasive fungal infections (IFIs) cause high rates of morbidity and mortality in immunocompromised patients. Pattern-recognition receptors present on the surfaces of innate immune cells recognize fungal pathogens and activate the first line of defense against fungal infection. The second line of defense is the adaptive immune system which involves mainly CD4+ T cells, while CD8+ T cells also play a role. CD8+ T cell-based vaccines designed to prevent IFIs are currently being investigated in clinical trials, their use could play an especially important role in acquired immune deficiency syndrome patients. So far, none of the vaccines used to treat IFI have been approved by the FDA. Here, we review current and future antifungal immunotherapy strategies involving CD8+ T cells. We highlight recent advances in the use of T cells engineered using a Sleeping Beauty vector to treat IFIs. Recent clinical trials using chimeric antigen receptor (CAR) T-cell therapy to treat patients with leukemia have shown very promising results. We hypothesized that CAR T cells could also be used to control IFI. Therefore, we designed a CAR that targets β-glucan, a sugar molecule found in most of the fungal cell walls, using the extracellular domain of Dectin-1, which binds to β-glucan. Mice treated with D-CAR+ T cells displayed reductions in hyphal growth of Aspergillus compared to the untreated group. Patients suffering from IFIs due to primary immunodeficiency, secondary immunodeficiency (e.g., HIV), or hematopoietic transplant patients may benefit from bioengineered CAR T cell therapy.

Modulating host immune responses to fight invasive fungal infections

Modulation of host immunity in invasive fungal infection is an appealing but as yet mostly elusive treatment strategy. Animal studies in invasive candidiasis and aspergillosis have demonstrated beneficial effects of colony stimulating factors, interferon-gamma and monoclonal antibodies. More recent studies transfusing leukocytes pre-loaded with lipophilic anti-fungal drugs, or modulated T-cells, along with novel vaccination strategies show great promise. The translation of immune therapies into clinical studies has been limited to date but this is changing and the results of new Candida vaccine trials are eagerly awaited. Immune modulation in HIV-associated mycoses remains complicated by the risk of immune reconstitution inflammatory syndrome and although exogenous interferon-gamma therapy may be beneficial in cryptococcal meningitis, early initiation of anti-retroviral therapy leads to increased mortality. Further study is required to better target protective immune responses.

Granulocyte transfusions: A concise review for practitioners

Granulocyte transfusions (GTXs) have been used to treat and prevent infections in neutropenic patients for more than 40 years, despite persistent controversy regarding their efficacy. This narrative review attempts to complement recent systematic reviews by the Cochrane Collaboration and provide both historical context and critical assessment of the most significant clinical studies published over the years. The data suggest that properly collected and promptly infused granulocytes are active against infections, both bacterial and fungal. The most important question that remains unanswered is in which patients the administration of granulocytes will be beneficial. The preponderance of evidence suggests that granulocyte transfusions may be efficacious in few select cases as a temporizing measure to control an infection that is expected (or proven) to be refractory to optimal antimicrobial treatment, and that could otherwise be controlled by marrow recovery, which is expected to happen. In this regard, they are best considered a "bridge" that grants enough time for the recipient to develop their own response to the infection. The challenges to use GTXs successfully are both clinical, in terms of timely identifying the patients who may benefit, and logistical, in terms of optimal selection of donors and collection technique.

Granulocyte transfusions in the management of invasive fungal infections

Granulocyte transfusions have a long history of being used in patients with neutropenia or neutrophil dysfunction to prevent and treat invasive fungal infections. However, there are limited and conflicting data concerning its clinical effectiveness, considerable variations in current granulocyte transfusion practices, and uncertainties about its benefit as an adjunct to modern antifungal therapy. In this review, we provide an overview on granulocyte transfusions and summarize the evidence on their role in the prevention and treatment of invasive fungal infections.

Optimizing Outcomes in Immunocompromised Hosts: Understanding the Role of Immunotherapy in Invasive Fungal Diseases

A major global concern is the emergence and spread of systemic life-threatening fungal infections in critically ill patients. The increase in invasive fungal infections, caused most commonly by Candida and Aspergillus species, occurs in patients with impaired defenses due to a number of reasons such as underlying disease, the use of chemotherapeutic and immunosuppressive agents, broad-spectrum antibiotics, prosthetic devices and grafts, burns, neutropenia and HIV infection. The high morbidity and mortality associated with these infections is compounded by the limited therapeutic options and the emergence of drug resistant fungi. Hence, creative approaches to bridge the significant gap in antifungal drug development needs to be explored. Here, we review the potential anti-fungal targets for patient-centered therapies and immune-enhancing strategies for the prevention and treatment of invasive fungal diseases.

Granulocyte transfusions in children and adults with hematological malignancies: benefits and controversies

Bacterial and fungal infections continue to pose a major clinical challenge in patients with prolonged severe neutropenia after chemotherapy or hematopoietic stem cell transplantation (HSCT). With the advent of granulocyte colony-stimulating factor (G-CSF) to mobilize neutrophils in healthy donors, granulocyte transfusions have been broadly used to prevent and/or treat life-threatening infections in patients with severe febrile neutropenia and/or neutrophil dysfunction. Although the results of randomized controlled trials are inconclusive, there are suggestions from pilot and retrospective studies that granulocyte transfusions may benefit selected categories of patients. We will critically appraise the evidence related to the use of therapeutic granulocyte transfusions in children and adults, highlighting current controversies in the field and discussing complementary approaches to modulate phagocyte function in the host.

Efficacy of transfusion with granulocytes from G-CSF/dexamethasone-treated donors in neutropenic patients with infection

High-dose granulocyte transfusion therapy has been available for 20 years, yet its clinical efficacy has never been conclusively demonstrated. We report here the results of RING (Resolving Infection in Neutropenia with Granulocytes), a multicenter randomized controlled trial designed to address this question. Eligible subjects were those with neutropenia (absolute neutrophil count <500/μL) and proven/probable/presumed infection. Subjects were randomized to receive either (1) standard antimicrobial therapy or (2) standard antimicrobial therapy plus daily granulocyte transfusions from donors stimulated with granulocyte colony-stimulating factor (G-CSF) and dexamethasone. The primary end point was a composite of survival plus microbial response, at 42 days after randomization. Microbial response was determined by a blinded adjudication panel. Fifty-six subjects were randomized to the granulocyte arm and 58 to the control arm. Transfused subjects received a median of 5 transfusions. Mean transfusion dose was 54.9 × 10(9) granulocytes. Overall success rates were 42% and 43% for the granulocyte and control groups, respectively (P > .99), and 49% and 41%, respectively, for subjects who received their assigned treatments (P = .64). Success rates for granulocyte and control arms did not differ within any infection type. In a post hoc analysis, subjects who received an average dose per transfusion of ≥0.6 × 10(9) granulocytes per kilogram tended to have better outcomes than those receiving a lower dose. In conclusion, there was no overall effect of granulocyte transfusion on the primary outcome, but because enrollment was half that planned, power to detect a true beneficial effect was low. RING was registered at www.clinicaltrials.gov as #NCT00627393.

Anti-infective prophylaxis in pediatric patients with acute myeloid leukemia

Pediatric patients undergoing treatment for acute myeloid leukemia (AML) are at high risk for infectious complications, predominantly due to Gram-negative bacteria, viridans group streptococci and fungal pathogens. In order to prevent infections in these patients, most institutions have implemented a number of non-pharmacological approaches to supportive care. In addition, antibiotic prophylaxis reduces bacterial infection, but may increase the emergence of resistance. Antifungal prophylaxis is generally recommended for children with AML. Whereas the use of hematopoietic growth factors has not resulted in improved survival, the efficacy of prophylactic granulocyte transfusions has to be determined.

Immunotherapeutic strategies against mucormycosis in haematopoietic stem cell transplantation

Mucormycoses remain a serious complication in patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT). In these patients, mortality rates of mucormycosis reach up to 90%, which is due, at least in part, to the severe and prolonged immunosuppression after transplantation. Although prolonged neutropaenia is one of the most important risk factors for mucormycosis, other cell populations, such as CD4(+) T cells may also provide critical defence mechanisms against this infection. The management of mucormycosis includes antifungal therapy, surgery and, most importantly, the control of the underlying predisposing conditions, such as the correction of an impaired immune system. Here, we review the current data of granulocytes, antifungal T cells and natural killer cells regarding their activity against mucormycetes and regarding a potential immunotherapeutic approach. It is hoped that further animal studies and clinical trials assessing immunotherapeutic strategies will ultimately improve the poor prognosis of allogeneic HSCT recipients suffering from mucormycosis.

Preventing invasive fungal disease in patients with haematological malignancies and the recipients of haematopoietic stem cell transplantation: practical aspects

Invasive fungal disease (IFD), predominantly aspergillosis, is associated with significant morbidity and mortality in immunocompromised patients, especially those with haematological malignancies and recipients of allogeneic haematopoietic stem cell transplantation. There has been a great deal of scientific debate as to the effectiveness of antifungal prophylaxis in preventing infection in different patient groups and in which patients it is an appropriate management option. Deciding on an appropriate prophylaxis regimen for IFD is challenging as the incidence varies among different patient groups, due to the varied nature of their underlying haematological disease, and in different regions and centres. Attempts have been made to define risk factors and include them in treatment protocols. Impaired immune status of the patient, especially neutropenia, is a key risk factor for IFD and can sometimes be related to specific polymorphisms of genes controlling innate immunity. Risk factors also vary according to the type of fungal pathogen. Consequently, prophylaxis needs to be tailored to individual patient groups. Furthermore, the choice of antifungal agent for prophylaxis depends on the potential for drug-drug interactions with the patients' concomitant medications. Additional challenges are optimal timing of antifungal prophylaxis, when to change from prophylaxis to antifungal treatment and how to prevent recurrence of IFD. This article considers the use of antifungal prophylaxis for patients at risk of IFD in daily clinical practice, with clinical profiles that may be distinct from those covered by guidelines, and aims to provide practical advice for treatment of these patient groups.

Concise review: next-generation cell therapies to prevent infections in neutropenic patients

High-dose chemotherapy is accompanied by an obligate period of neutropenia. Resulting bacterial and fungal infections are the leading cause of morbidity and mortality in neutropenic patients despite prophylactic antimicrobials and hematopoietic growth factor supplements. Replacing neutrophils in the patient through transfusion of donor cells is a logical solution to prevent fulminant infections. In the past, this strategy has been hampered by poor yield, inability to store collected cells, and possible donor morbidity caused by granulocyte colony-stimulating factor injections and apheresis. Today, neutrophil-like cells can be manufactured in the laboratory at the clinical scale from hematopoietic stem and progenitor cells enriched from umbilical cord blood. This article reviews the rationale for focusing research efforts toward ex vivo neutrophil production and explores clinical settings for future trials.

Immunomodulatory therapy in yeast infections

Invasive yeast infections are a significant cause of morbidity and mortality in patients with defective immune response, such as those with cancer-related immunosuppression, organ transplantation or other immunodeficiencies, and neonates. Hospitalization in the intensive care unit may increase the risk for such infections. Despite the advent of new antifungal agents, the problem is escalating as the number of susceptible hosts increase and virulent, more resistant fungal strains emerge. Over the past few years, advances in immunology and molecular biology have greatly contributed to a better understanding of the pathogenesis of yeast infections. There is evidence that reconstitution of the host immune function is a major contributor to the resolution of yeast infections. Strategies aiming to increase the phagocyte number (e.g., granulocyte transfusions), to stimulate immune response (e.g., administration of hematopoietic growth factors and other proinflammatory cytokines) and to stimulate antigen-specific immunity (e.g., antibody therapy or vaccination) benefit patients at risk of, or suffering from, yeast infections. Further preclinical and clinical studies, as well as improving our understanding of immune system functions and dysfunctions, remain a future challenge.

Use of healthy-donor granulocyte transfusions to treat infections in neutropenic patients with myeloid or lymphoid neoplasms: experience in 74 patients treated with 373 granulocyte transfusions

BACKGROUND/AIMS

Despite limited evidence for efficacy, granulocyte transfusions (GTX) are used to prevent and treat opportunistic infections in patients with neutropenia.

METHODS

Three hundred and seventy-three GTX given to 74 patients were assessed retrospectively.

RESULTS

GTX were discontinued because of clinical improvement more often in patients with severe infections than in patients without severe infections (27 vs. 12%; p ≤ 0.002), whereas deaths resulted in discontinuation of GTX therapy less often in patients with severe infections than without (8 vs. 39%; p ≤ 0.002). Patients who died by 12 weeks after GTX initiation were more likely to have leukemia (p = 0.03), not to have recovery of neutrophil counts (p < 0.0001), and to have started GTX during a critical care unit stay (p < 0.001). Uses of granulocyte colony-stimulating factor (p ≤ 0.02) and interferon-γ (p ≤ 0.04) were more common in patients who survived. In patients with comorbidities (31%; odds ratio, OR, 12.6; 95% confidence interval, CI, 2.4-65.7; p ≤ 0.003), GTX was started in the critical care unit (OR 8.8; 95% CI 2.5-30.9; p < 0.001), and a high total bilirubin level at the end of GTX (OR 2.1; 95% CI 1.1-4.2; p = 0.03) had a higher probability of death 12 weeks after GTX therapy commenced.

CONCLUSIONS

The possibility that a niche population may benefit from GTX requires further assessment.

Treatment of invasive fungal infections in cancer patients-updated recommendations of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO)

The Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO) here presents its updated recommendations for the treatment of documented fungal infections. Invasive fungal infections are a main cause of morbidity and mortality in cancer patients undergoing intensive chemotherapy regimens. In recent years, new antifungal agents have been licensed, and agents already approved have been studied in new indications. The choice of the most appropriate antifungal treatment depends on the fungal species suspected or identified, the patient's risk factors (e.g., length and depth of neutropenia), and the expected side effects. This guideline reviews the clinical studies that served as a basis for the following recommendations. All recommendations including the levels of evidence are summarized in tables to give the reader rapid access to the information.

Long-term social isolation in the adulthood results in CA1 shrinkage and cognitive impairment

Social isolation in adulthood is a psychosocial stressor that can result in endocrinological and behavioral alterations in different species. In rodents, controversial results have been obtained in fear conditioning after social isolation at adulthood, while neural substrates underlying these differences are largely unknown. Neural cell adhesion molecule (NCAM) and its polysialylated form (PSA-NCAM) are prominent modulators of synaptic plasticity underlying memory processes in many tasks, including fear conditioning. In this study, we used adult female Octodon degus to investigate the effects of long-term social isolation on contextual and cued fear conditioning, and the possible modulation of the synaptic levels of NCAM and PSA-NCAM in the hippocampus. After 6½ months of social isolation, adult female degus showed a normal auditory-cued fear memory, but a deficit in contextual fear memory, a hippocampal dependent task. Subsequently, we observed reduced hippocampal synaptic levels of PSA-NCAM in isolated compared to grouped-housed female degus. No significant differences were found between experimental groups in hippocampal levels of the three main isoforms of NCAM (NCAM180, NCAM140 and NCAM120). Interestingly, social isolation reduced the volume of the hippocampal CA1 subfield, without affecting the volume of the CA3 subregion or the total hippocampus. Moreover, attenuated body weight gain and reduced number of granulocytes were detected in isolated animals. Our findings indicate for the first time, that long-term social isolation of adult female animals induces a specific shrinkage of CA1 and a decrease in synaptic levels of PSA-NCAM in the hippocampus. These effects may be related to the deficit in contextual fear memory observed in isolated female degus.

Immune modulators as adjuncts for the prevention and treatment of invasive fungal infections

Invasive fungal diseases are increasingly important opportunistic infections that are intimately linked to immune-suppression in the context of cytotoxic treatment of neoplastic diseases, stem cell and solid-organ transplantation, and primary immune deficiencies. Mortality rates remain high despite the availability of novel antifungals that are both safe and highly active in vitro, suggesting that clinical outcomes may be improved through modulation of host immunity. Ongoing advances in our knowledge of fungal-host interactions facilitate rational design of novel immunotherapeutics. Thus, antifungal immunotherapy now includes age-old interventions such as granulocyte and immunoglobulin transfusions, as well as promising experimental techniques such as antifungal vaccines and adoptive immunotherapy. To realize the potential of these rapidly evolving technologies, transition from the bench to clinical-phase studies must occur at a more rapid pace.

Invasive fungal infections in acute leukemia

Invasive fungal infection (IFI) is among the leading causes for morbidity, mortality, and economic burden for patients with acute leukemia. In the past few decades, the incidence of IFI has increased dramatically. The certainty of diagnosis of IFI is based on host factors, clinical evidence, and microbiological examination. Advancement in molecular diagnostic modalities (e.g. non-culture-based serum biomarkers such as β-glucan or galactomannan assays) and high-resolution radiological imaging has improved our diagnostic approach. The early use of these diagnostic tests assists in the early initiation of preemptive therapy. Nonetheless, the complexity of IFI in patients with leukemia and the limitations of these diagnostic tools still mandate astute clinical acumen. Its management has been further complicated by the increasing frequency of infection by non-Aspergillus molds (e.g. zygomycosis) and the emergence of drug-resistant fungal pathogens. In addition, even though the antifungal armamentarium has expanded rapidly in the past few decades, the associated mortality remains high. The decision to initiate antifungal treatment and the choice of anti-fungal therapy requires careful consideration of several factors (e.g. risk stratification, local fungal epidemiologic patterns, concomitant comorbidities, drug-drug interactions, prior history of antifungal use, overall cost, and the pharmacologic profile of the antifungal agents). In order to optimize our diagnostic and therapeutic management of IFI in patients with acute leukemia, further basic research and clinical trials are desperately needed.

Experimental evidence that granulocyte transfusions are efficacious in treatment of neutropenic hosts with pulmonary aspergillosis

Although polymorphonuclear leukocytes (PMNs) are powerfully anti-Aspergillus, transfusion therapy remains controversial, with conflicting results, and experimental support has been lacking. We devised a pulmonary infection model in neutropenic BALB/c mice, used an antibacterial regimen to prevent confounding sepsis, and optimized PMN induction, purifications, and dose. Mice were given 150 mg/kg cyclophosphamide every 4 days and a gentamicin-vancomycin-clindamycin-imipenem regimen daily beginning 4 days before intranasal challenge with 5 × 10(5) Aspergillus conidia. This regimen produced leukopenia (~10% of normal white blood cell [WBC] count; ≤ 10% PMNs) for 10 days, without bacterial superinfection. PMN donors given 100 μg/kg recombinant murine granulocyte colony-stimulating factor (G-CSF) for 10 days yielded 11 × 10(7) to 13.6 × 10(7) WBC/ml (81 to 87% PMNs). Infected mice were given PMN transfusions intravenously. In 2 experiments with up to 70% mortality of neutropenic controls, transfusion of 10(7) PMNs 1 and 4 days after challenge had negligible effects on peripheral WBC counts but improved survival (P = 0.007, 0.02), decreased lung CFU (P = 0.03, 0.005), and cleared infection in 28 to 50% of survivors. Transfusion of 5 × 10(6) PMNs showed partial protection. Transfusions given every other day did not improve protection. Our present results provide an experimental basis for enthusiasm for PMN transfusions in the therapy of aspergillosis in humans.

Immunotherapy against invasive mold infections

Invasive infections due to filamentous fungi, such as Aspergillus spp., Zygomycetes, Scedosporium and Fusarium spp., cause significant morbidity and mortality in immunocompromised patients with hematological malignancies, recipients of hematopoietic stem cell transplants and those with chronic granulomatous disease. Despite antifungal therapy, the outcome is often unfavorable in these patients; immune restoration is considered as the cornerstone of successful treatment. Important aspects of human immune response against fungi include effective innate immune response expressed as effective phagocytic functions and a balance between proinflammatory and regulatory adaptive immune responses. A number of immunomodulatory approaches, including the administration of enhancing cytokines, adoptive transfer of pathogen-specific T lymphocytes and granulocyte transfusions have been investigated as adjunctive treatments against serious mold infections. Despite encouraging in vitro and in vivo data, current clinical evidence is not sufficient to allow firm recommendations on the use of these immunomodulatory modalities in serious mold infections.

Uncommon mold infections in hematological patients: epidemiology, diagnosis and treatment

Invasive fungal diseases continue to be an important cause of morbidity and mortality in immunosuppressed patients. This is of particular interest, since the progress we made in the treatment of underlying malignancies has led to an increase of the number of persons 'at high risk'. During the last few years, several changes in clinical practice in hematology (new immunosuppressants, hematopoietic stem cell transplants) have influenced the epidemiology of invasive fungal diseases; in particular, cases due to some uncommon etiologic agents are being increasingly reported, making it even more urgent to reconsider differential diagnoses in high-risk patients. A better understanding of epidemiology, risk factors and prognosis appears to be crucial to analyze prevention and diagnostic strategies, as well as to guarantee an early and adequate treatment.

Immunotherapy of infections caused by rare filamentous fungi

Invasive fungal infections caused by rare filamentous fungi constitute a significant cause of morbidity and mortality in patients with defective immune responses. Despite the advent of new antifungal agents, the problem is escalating as the number of susceptible hosts increases and virulent, more resistant fungal strains emerge. There is evidence that reconstitution of the host immune function is a major contributor to the resolution of these infections. Therapeutic modalities aimed at increasing phagocyte numbers, such as granulocyte transfusions, stimulating the immune response, such as administration of haematopoietic growth factors and other proinflammatory cytokines, or indirectly augmenting immune function have shown promising results in the preclinical setting. Because of the rarity of the infections, multicentre clinical trials are needed to demonstrate the efficacy and safety of the new immunomodulating approaches.

Mucormycosis: its contemporary face and management strategies

Several countries have seen rising frequencies of mucormycosis among patients with haematological disorders, malignancies, or diabetes mellitus, and among transplant recipients. Growing numbers of immunocompromised hosts, widespread use of antifungal agents inactive against mucormycosis, or other unidentified factors, could be contributing to this situation. The predominant clinical manifestations of mucormycosis vary from host to host. Additionally, risk factors specific to different subgroups have been identified, such as leukaemia, allogeneic haemopoietic stem-cell transplant, voriconazole prophylaxis, diabetes, and malnutrition. We summarise the current state of knowledge of characteristics and risk factors and discuss topical developments in therapeutic methods and strategies in the management of mucormycosis.

Immunotherapy against invasive fungal diseases in stem cell transplant recipients

Despite the availability of new antifungal compounds, morbidity and mortality of invasive fungal disease in allogeneic hematopoietic stem cell recipients are still unacceptably high. Over the past decade, one could witness an exciting improvement of the understanding of the molecular pathogenesis and of the complexity of host antifungal immune responses. This, in turn, provides critical information to augment host immunity against fungal pathogens. Strategies for enhancing the immune system include the administration of effector and regulatory cells (e.g., granulocytes, antigen-specific T cells, dendritic cells) as well as the administration of recombinant cytokines, interferons and growth factors (e.g., interferon-γ, keratinocyte growth factor, granulocyte- and granulocyte-macrophage colony stimulating factor). One has to recognize at the same time, however, that data of in vitro assays and animal models cannot necessarily be transferred into the clinical setting. In addition, meaningful clinical trials in allogeneic stem cell recipients suffering from invasive fungal disease require sufficiently large and homogenous cohorts of patients and can only be performed in international collaboration, but may ultimately improve the outcome of allogeneic transplant recipients with invasive fungal disease.

How I treat mucormycosis

Unlike invasive aspergillosis, the prognosis and outcome of hematologic malignancy patients who develop invasive mucormycosis have not significantly improved over the past decade as a majority of patients who develop the infection still die 12 weeks after diagnosis. However, early recognition and treatment of invasive mucormycosis syndromes, as well as individualized approaches to treatment and secondary prophylaxis, could improve the odds of survival, even in the most persistently immunosuppressed patient receiving chemotherapy and/or of stem cell transplantation. Herein, we describe the subtle clinical and radiographic clues that should alert the hematologist to the possibility of mucormycosis, and aggressive and timely treatment approaches that may limit the spread of infection before it becomes fatal. Hematology patients with this opportunistic infection require integrated care across several disciplines and frequently highly individualized and complex sequence of decision-making. We also offer perspectives for the use of 2 antifungals, amphotericin B products and posaconazole, with activity against Mucorales. The availability of posaconazole in an oral formulation that can be administered safely for prolonged periods makes it an attractive agent for long-term primary and secondary prophylaxis. However, serum drug concentration monitoring may be required to minimize breakthrough infection or relapsing mucormycosis associated with inadequate blood concentrations.

Treatment of severe neutropenic sepsis with granulocyte transfusion in the current era--experience from an adult haematology unit in Singapore

OBJECTIVES

Granulocyte transfusion's (GT) efficacy among adult severe neutropenic sepsis (SNS) patients remains uncertain. We assessed GT's efficacy and its determinants among SNS patients in an adult haematology unit. The feasibility and safety of granulocyte donation (GD) and determinants of granulocyte yield were also evaluated.

METHODS

Retrospective analysis of granulocyte donors and recipients from March 2008 to October 2009.

RESULTS

Donors: Sixty GDs with a median WBC yield (WBCY) of 65·49 (31·30-131·72) × 10(9) were collected from 48 donors (9 repeat donors) using hydroxyethyl starch and intermittent flow centrifugation aphaeresis after receiving 8 mg dexamethasone and 300 mcg granulocyte colony-stimulating factor, with no serious adverse reactions (SAR). Six donations were urgently collected <3 h after pre-medication, the median WBCY of which was not significantly different from donations collected >12 h after pre-medication [59·18 (45·68-62·90) × 10(9) vs 67·45 (31·30-131·72) × 10(9) , P = 0·140]. Only pre-GD absolute neutrophil count (ANC) correlated with WBCY.

PATIENTS

Fifteen patients (12 acute leukaemias, 1 severe AA, 1 myelodysplastic syndrome and 1 lymphoma) received median 3 (2-9) ABO/RhD-matched GTs over 2-24 (median 7) days at 3-61 (median 28) days from severe neutropenia (SN) onset without SAR. They received intensive chemotherapies (N = 9), allogeneic transplant (N = 3), autologous stem cell rescue (N = 1) or immunosuppressants (N = 2). Fourteen had bacterial (N = 1) infections, fungal (N = 3) infections or both (N = 10) and one had severe viral pneumonitis; 63·6 and 30·8% of bacterial and fungal infections responded, respectively. Median ANC increase (ANC(increase) ) was 1·26 (0-9·25) × 10(9) at 5-20 (median 11) h post-GT. On multivariate analysis, each patient's median ANC(increase) only significantly correlated positively with median WBC dose/kg (P = 0·013). Five (33·3%) patients survived to discharge; the rest had infection-related mortality (IRM). IRM was significantly associated with inotropic requirement (P = 0·004), ventilatory requirement (P = 0·017) and persistent SN (P = 0·007).

CONCLUSION

GD is safe and feasible with good WBCY obtainable using our protocol. The effect of shortening pre-medication interval on WBCY which may prevent delay in initiating GT is worth evaluating. GT most likely benefits SNS patients with prospects of neutrophil recovery before haemodynamic deterioration. Large randomised trials investigating the role and timing of GT among such patients are required.