Fungal infections in transplant and oncology patients

Searching for Conjugates as New Structures for Antifungal Therapies

The progressive increase in fungal infections and the decrease in the effectiveness of current therapy explain research on new drugs. The synthesis of compounds with proven antifungal activity, favorable physicochemical and pharmacokinetic properties affecting their pharmaceutical availability and bioavailability, and limiting or eliminating side effects has become the goal of many studies. The publication describes the directions of searching for new compounds with antifungal activity, focusing on conjugates. The described modifications include, among others, azoles or amphotericin B in combination with fatty acids, polysaccharides, proteins, and synthetic polymers. The benefits of these combinations in terms of activity, mechanism of action, and bioavailability were indicated. The possibilities of creating or using nanoparticles, "umbrella" conjugates, siderophores (iron-chelating compounds), and monoclonal antibodies were also presented. Taking into account the role of vaccinations in prevention, the scope of research related to developing a vaccine protecting against fungal infections was also indicated.

The current state of laboratory mycology in Asia/Pacific: A survey from the European Confederation of Medical Mycology (ECMM) and International Society for Human and Animal Mycology (ISHAM)

INTRODUCTION

Invasive fungal infections (IFIs) in Asia/Pacific are a particular threat to patients with malignancies, uncontrolled diabetes mellitus or undiagnosed/untreated human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS). Adequate and early access to diagnostic tools and antifungals is essential for IFI clinical management and patient survival.

METHODS

Details on institution profile, self-perception on IFI, and access to microscopy, culture, serology, antigen detection, molecular testing, and therapeutic drug monitoring for IFI were collected in a survey.

RESULTS

As of June 2022, 235 centres from 40 countries/territories in Asia/Pacific answered the questionnaire. More than half the centres were from six countries: India (25%), China (17%), Thailand (5%), Indonesia, Iran, and Japan (4% each). Candida spp. (93%) and Aspergillus spp. (75%) were considered the most relevant pathogens. Most institutions had access to microscopy (98%) or culture-based approaches (97%). Furthermore, 79% of centres had access to antigen detection, 66% to molecular assays, and 63% to antibody tests. Access to antifungals varied between countries/territories. At least one triazole was available in 93% of the reporting sites (voriconazole [89%] was the most common mould-active azole), whereas 80% had at least one amphotericin B formulation, and 72% had at least one echinocandin.

CONCLUSION

According to the replies provided, the resources available for IFI diagnosis and management vary among Asia/Pacific countries/territories. Economical or geographical factors may play a key role in the incidence and clinical handling of this disease burden. Regional cooperation may be a good strategy to overcome shortcomings.

Genetic Vaccination as a Flexible Tool to Overcome the Immunological Complexity of Invasive Fungal Infections

The COVID-19 pandemic has highlighted genetic vaccination as a powerful and cost-effective tool to counteract infectious diseases. Invasive fungal infections (IFI) remain a major challenge among immune compromised patients, particularly those undergoing allogeneic hematopoietic bone marrow transplantation (HSCT) or solid organ transplant (SOT) both presenting high morbidity and mortality rates. Candidiasis and Aspergillosis are the major fungal infections among these patients and the failure of current antifungal therapies call for new therapeutic aids. Vaccination represents a valid alternative, and proof of concept of the efficacy of this approach has been provided at clinical level. This review will analyze current understanding of antifungal immunology, with a particular focus on genetic vaccination as a suitable strategy to counteract these diseases.

Association between adenovirus infection and mortality outcome among pediatric patients after hematopoietic stem cell transplant

BACKGROUND

Adenovirus can cause severe diseases in post-hematopoietic stem cell transplant (HSCT) patients. Because these patients also have many other factors contributing to mortality, it remains controversial whether adenovirus infection itself contributes to increased mortality in these patients.

OBJECTIVE

To determine if adenovirus infection contributes to mortality in pediatric post-HSCT patients.

METHODS

This retrospective cohort study was performed in post HSCT patients, aged 0-18 years old, admitted at Ramathibodi Hospital from 2016 to 2020. Adenovirus infection was defined as the detection of adenovirus in blood or urine by polymerase chain reaction. Multivariate cox regression was used to identify factors associated with death.

RESULTS

The incidence of overall adenovirus infection (viremia or viruria) in this cohort was 20.8% (26 out of 125 enrolled patients). From the multivariate cox regression analysis, overall adenovirus infection was not significantly associated with death (hazard ratio [HR]: 2.41; 95% confidence interval [CI]: 0.96-6.06; p = .060). However, presence of viremia (HR: 3.90; 95% CI: 1.40-10.86; p = .009), having maximal serum viral load > 10 000 copies/ml (HR: 3.70; 95% CI: 1.20-11.38; p = .023), presence of end-organ diseases (HR: 3.44; 95% CI: 1.18-10.01; p = .023) were associated with mortality. Underlying diseases requiring long-term immunosuppressive drugs before HSCT, invasive fungal disease, invasive bacterial infection, cytomegalovirus infection, and longer engraftment time were also associated with mortality.

CONCLUSION

Overall adenovirus infection does not appear to play a significant role in mortality in pediatric post-HSCT patients. However, more invasive forms of adenovirus infection were associated with mortality in these patients.

Fungal infections in hematopoietic stem-cell transplant patients: a review of epidemiology, diagnosis, and management

The advent of bone marrow transplant has opened doors to a different approach and offered a new treatment modality for various hematopoietic stem-cell-related disorders. Since the first bone marrow transplant in 1957, there has been significant progress in managing patients who undergo bone marrow transplants. Plasma-cell disorders, lymphoproliferative disorders, and myelodysplastic syndrome are the most common indications for hematopoietic stem-cell transplant. Despite the advances, invasive fungal infections remain a significant cause of morbidity and mortality in this high-risk population. The overall incidence of invasive fungal infection in patients with hematopoietic stem-cell transplant is around 4%, but the mortality in patients with allogeneic stem-cell transplant is as high as 13% in one study. Type of stem-cell transplant, conditioning regimen, and development of graft-versus-host disease are some of the risk factors that impact the risk and outcomes in patients with invasive fungal infections. Aspergillus and candida remain the two most common organisms causing invasive fungal infections. Molecular diagnostic methods have replaced some traditional methods due to their simplicity of use and rapid turnaround time. Primary prophylaxis has undoubtedly shown to improve outcomes even though breakthrough infection rates remain high. The directed treatment has seen a significant shift from amphotericin B to itraconazole, voriconazole, and echinocandins, which have shown better efficacy and fewer adverse effects. In this comprehensive review, we aim to detail epidemiology, risk factors, diagnosis, and management, including prophylaxis, empiric and directed management of invasive fungal infections in patients with hematopoietic stem-cell transplant.

Treatment of infections in cancer patients: an update from the neutropenia, infection and myelosuppression study group of the Multinational Association for Supportive Care in Cancer (MASCC)

INTRODUCTION

Patients with hematological and advanced solid malignancies have acquired immune dysfunction, often exacerbated by treatment, posing a significant risk for the development of infections. This review evaluates the utility of current clinical and treatment guidelines, in the setting of management of infections in cancer patients.

AREAS COVERED

These include causes of infection in cancer patients, management of patients with high-risk and low-risk febrile neutropenia, management of low-risk patients in an outpatient setting, the role of granulocyte colony-stimulating factor (G-CSF) in the prevention and treatment of neutropenia-related infections, management of lung infections in various clinical settings, and emerging challenges surrounding the risk of infection in cancer patients treated with novel treatments. The literature search was performed by accessing PubMed and other databases, focusing on published clinical trials of relevant anti-cancer agents and diseases, primarily covering the recent past, but also including several key studies published during the last decade and, somewhat earlier in a few cases.

EXPERT REVIEW

Notwithstanding the promise of gene therapy/gene editing in hematological malignancies and some types of solid cancers, innovations introduced in clinical practice include more discerning clinical management such as the generalized use of biosimilar formulations of G-CSF and the implementation of novel, innovative immunotherapies.

Long-Term Follow-Up After the Application of Mesenchymal Stromal Cells in Children and Adolescents with Steroid-Refractory Graft-Versus-Host Disease

Steroid-refractory graft-versus-host disease (GvHD) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (alloHSCT). Alternative treatment options are often insufficient. Several studies have proven the efficacy of mesenchymal stromal cells (MSCs) in the treatment of therapy-refractory acute GvHD in adult and pediatric patients. Long-term data in pediatric patients are scarce. In this retrospective analysis, a total of 25 patients with a median age of 10.6 years (range 0.6-22.1 years) who received bone marrow-derived MSCs after alloHSCT for the treatment of steroid-refractory III and IV GvHD were analyzed. The median observation period of the surviving patients was 9.3 years (1.3-12.7 years) after HSCT. Among the 25 patients, 10 (40.0%) died [relapse (n = 3), multiorgan failure (n = 6), cardiorespiratory failure (n = 1)] at median 0.5 years (0.2-2.3 years) after HSCT. Partial response and complete remission (PR, CR) of the GvHD were achieved in 76.0% and 24.0% of the patients, respectively. Transplant-related mortality was 0% in the patients who achieved CR after MSC treatment and 26.3% for those with PR. A median improvement by one intestinal or liver GvHD stage (range 1-4) could be achieved after MSC application. No potentially MSC-related long-term adverse effects, for example, secondary malignancy, were identified. In conclusion, the intravenous application of allogeneic MSCs was safe and proved effective for the treatment of steroid-refractory GvHD. However, larger, prospective, and randomized trials are needed to evaluate these findings.

Isavuconazole Prophylaxis in Patients With Hematologic Malignancies and Hematopoietic Cell Transplant Recipients

BACKGROUND

Isavuconazole (ISA) is an attractive candidate for primary mold-active prophylaxis in high-risk patients with hematologic malignancies or hematopoietic cell transplant (HCT) recipients. However, data supporting the use of ISA for primary prophylaxis in these patients are lacking.

METHODS

We conducted a retrospective review of breakthrough invasive fungal infections (bIFIs) among adult hematologic malignancy patients and HCT recipients who received ≥7 days of ISA primary prophylaxis between 1 September 2016 and 30 September 2018. The incidence of bIFIs in patients receiving ISA was compared to those receiving posaconazole (POS) and voriconazole (VOR) during the same time period.

RESULTS

One hundred forty-five patients received 197 courses of ISA prophylaxis. Twelve bIFIs (Aspergillus fumigatus [5], Aspergillus species [2], Mucorales [2], Fusarium species [2], and Candida glabrata [1]) occurred, representing 8.3% of patients and 6.1% of courses, after a median duration of 14 days of ISA prophylaxis. All bIFIs occurred during periods of neutropenia. Seven patients (58.3%) died within 42 days of onset of bIFI. In addition, bIFIs complicated 10.2% of ISA, 4.1% of POS, and 1.1% of VOR courses among patients with de novo or relapsed/refractory acute myeloid leukemia during the study period, with invasive pulmonary aspergillosis (IPA) complicating 6.8% of ISA, 1.3% of POS, and zero VOR courses.

CONCLUSIONS

Although ISA has been approved for treatment of invasive Aspergillus and mucormycosis, we observed an increased rate of bIFI, notably IPA, using ISA for primary prophylaxis. These results support the need for further study to determine the role of ISA as primary prophylaxis.

The role of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG PET/CT) in assessment of complex invasive fungal disease and opportunistic co-infections in patients with acute leukemia prior to allogeneic hematopoietic cell transplant

INTRODUCTION

Individuals diagnosed with acute lymphoid and myeloid malignancies are at significant risk of invasive fungal and bacterial infections secondary to their marked immunocompromised states with a significant high risk of mortality. The role of metabolic imaging with 18F-Fluorodeoxyglucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT) has been increasingly recognized in optimizing the diagnosis of invasive infection, monitoring the response to therapy and guiding the duration of antimicrobial therapy or need to escalate to surgical intervention.

METHODS

Two distinct cases of pulmonary co-infection of rare fungal and bacterial pathogens are explored in severely immunocompromised individuals where FDG PET/CT aided both patients to make a full recovery and transition to HCT. The first case explores mixed Scedosporium apiospermum and Rhizomucor pulmonary infection on a background of T cell/myeloid mixed phenotype acute leukemia ultimately warranting long-term antifungal therapy and lobectomy prior to HCT. The second case explores Fusarium and Nocardia pulmonary infection on a background of relapsed AML also warranting surgical resection with lobectomy and long-term antimicrobials prior to transition to HCT.

DISCUSSION

The cases highlight the utility of FDG PET/CT to support the diagnosis of infections, including the presence or absence of disseminated infection, and to provide highly sensitive monitoring of the infection over time. FDG PET/CT played a key role in directing therapy duration decisions and prompted the necessity for surgical intervention. Ultimately, the use of FDG PET/CT allowed for a successful transition to HCT highlighting its value in this clinical setting.

CONCLUSION

FDG PET/CT has an emerging role in the diagnostic and monitoring pathway for complex infections in high-risk immunocompromised patients.

Fluconazole is as effective as other anti-mold agents in preventing early invasive fungal disease after allogeneic stem cell transplantation: assessment of antifungal therapy in haematological disease in China

BACKGROUND

The introduction of mold-active antifungal drugs has led clinicians to reconsider the use of fluconazole for preventing invasive fungal disease (IFD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this study of recipients of allo-HSCT, we evaluated the effects of different antifungal prophylaxes on the incidence of IFD at different times after transplantation.

METHODS

Among the 1,401 patients registered in the prospective China Assessment of Antifungal Therapy in Haematological Disease (CAESAR) study database, there were 661 eligible patients who received primary antifungal prophylaxis. The incidence of IFD at different times after transplantation (early, late, and very late) and overall survival were compared for patients who received different drugs.

RESULTS

The overall incidence of probable IFD was 7.0% in the fluconazole group, 12.6% in the itraconazole group, 1.4% in the voriconazole group, and 5.2% in the micafungin group (P=0.0379). However, the four groups had no significant differences in early, late, or very late IFD. The risk factors associated with IFD were neutropenia for more than 14 days, age greater than 18 years, and receipt of transplantation from an alternative (unrelated and haploidentical) donor (P<0.05). Sub-group analysis of alternative donors indicated that the efficacy of fluconazole was similar to the other three drugs in preventing early IFD.

CONCLUSIONS

Our results suggest that the efficacy of fluconazole is similar to that of mold-active drugs in preventing early IFD in HSCT patients, even in high-risk patients receiving transplantation from alternative donors. Further prospective randomized studies are needed to confirm this conclusion.

Interactions of FK506 and Rapamycin With FK506 Binding Protein 12 in Opportunistic Human Fungal Pathogens

Over the past few decades advances in modern medicine have resulted in a global increase in the prevalence of fungal infections. Particularly people undergoing organ transplants or cancer treatments with a compromised immune system are at an elevated risk for lethal fungal infections such as invasive candidiasis, aspergillosis, cryptococcosis, etc. The emergence of drug resistance in fungal pathogens poses a serious threat to mankind and it is critical to identify new targets for the development of antifungals. Calcineurin and TOR proteins are conserved across eukaryotes including pathogenic fungi. Two small molecules FK506 and rapamycin bind to FKBP12 immunophilin and the resulting complexes (FK506-FKBP12 and rapamycin-FKBP12) target calcineurin and TOR, respectively in both humans and fungi. However, due to their immunosuppressive nature these drugs in the current form cannot be used as an antifungal. To overcome this, it is important to identify key differences between human and fungal FKBP12, calcineurin, and TOR proteins which will facilitate the development of new small molecules with higher affinity toward fungal components. The current review highlights FK506/rapamycin-FKBP12 interactions with calcineurin/TOR kinase in human and fungi, and development of non-immunosuppressive analogs of FK506, rapamycin, and novel small molecules in inhibition of fungal calcineurin and TOR kinase.

(1→3)-β-D-glucan testing for the detection of invasive fungal infections in immunocompromised or critically ill people

BACKGROUND

Invasive fungal infections (IFIs) are life-threatening opportunistic infections that occur in immunocompromised or critically ill people. Early detection and treatment of IFIs is essential to reduce morbidity and mortality in these populations. (1→3)-β-D-glucan (BDG) is a component of the fungal cell wall that can be detected in the serum of infected individuals. The serum BDG test is a way to quickly detect these infections and initiate treatment before they become life-threatening. Five different versions of the BDG test are commercially available: Fungitell, Glucatell, Wako, Fungitec-G, and Dynamiker Fungus.

OBJECTIVES

To compare the diagnostic accuracy of commercially available tests for serum BDG to detect selected invasive fungal infections (IFIs) among immunocompromised or critically ill people.

SEARCH METHODS

We searched MEDLINE (via Ovid) and Embase (via Ovid) up to 26 June 2019. We used SCOPUS to perform a forward and backward citation search of relevant articles. We placed no restriction on language or study design.

SELECTION CRITERIA

We included all references published on or after 1995, which is when the first commercial BDG assays became available. We considered published, peer-reviewed studies on the diagnostic test accuracy of BDG for diagnosis of fungal infections in immunocompromised people or people in intensive care that used the European Organization for Research and Treatment of Cancer (EORTC) criteria or equivalent as a reference standard. We considered all study designs (case-control, prospective consecutive cohort, and retrospective cohort studies). We excluded case studies and studies with fewer than ten participants. We also excluded animal and laboratory studies. We excluded meeting abstracts because they provided insufficient information.

DATA COLLECTION AND ANALYSIS

We followed the standard procedures outlined in the Cochrane Handbook for Diagnostic Test Accuracy Reviews. Two review authors independently screened studies, extracted data, and performed a quality assessment for each study. For each study, we created a 2 × 2 matrix and calculated sensitivity and specificity, as well as a 95% confidence interval (CI). We evaluated the quality of included studies using the Quality Assessment of Studies of Diagnostic Accuracy-Revised (QUADAS-2). We were unable to perform a meta-analysis due to considerable variation between studies, with the exception of Candida, so we have provided descriptive statistics such as receiver operating characteristics (ROCs) and forest plots by test brand to show variation in study results.

MAIN RESULTS

We included in the review 49 studies with a total of 6244 participants. About half of these studies (24/49; 49%) were conducted with people who had cancer or hematologic malignancies. Most studies (36/49; 73%) focused on the Fungitell BDG test. This was followed by Glucatell (5 studies; 10%), Wako (3 studies; 6%), Fungitec-G (3 studies; 6%), and Dynamiker (2 studies; 4%). About three-quarters of studies (79%) utilized either a prospective or a retrospective consecutive study design; the remainder used a case-control design. Based on the manufacturer's recommended cut-off levels for the Fungitell test, sensitivity ranged from 27% to 100%, and specificity from 0% to 100%. For the Glucatell assay, sensitivity ranged from 50% to 92%, and specificity ranged from 41% to 94%. Limited studies have used the Dynamiker, Wako, and Fungitec-G assays, but individual sensitivities and specificities ranged from 50% to 88%, and from 60% to 100%, respectively. Results show considerable differences between studies, even by manufacturer, which prevented a formal meta-analysis. Most studies (32/49; 65%) had no reported high risk of bias in any of the QUADAS-2 domains. The QUADAS-2 domains that had higher risk of bias included participant selection and flow and timing.

AUTHORS' CONCLUSIONS

We noted considerable heterogeneity between studies, and these differences precluded a formal meta-analysis. Because of wide variation in the results, it is not possible to estimate the diagnostic accuracy of the BDG test in specific settings. Future studies estimating the accuracy of BDG tests should be linked to the way the test is used in clinical practice and should clearly describe the sampling protocol and the relationship of time of testing to time of diagnosis.

Dapsone for Pneumocystis jirovecii pneumonia prophylaxis - applying theory to clinical practice with a focus on drug interactions

Pneumocystis jirovecii pneumonia (PJP) is a potentially life-threatening infection that occurs in immunocompromised individuals. The incidence can be as high as 80% in some groups but can be reduced to less than 1% with appropriate prophylaxis. HIV-infected patients with a low CD4 count are at the highest risk of PJP. Others at substantial risk include haematopoietic stem cell and solid organ transplant recipients, those with cancer (particularly haematologic malignancies), and those receiving glucocorticoids, chemotherapeutic agents, and other immunosuppressive medications. Trimethoprim-sulfamethoxazole is an established first-line line agent for prevention and treatment of PJP. However, in some situations, this medication cannot be used and dapsone is considered a suitable cost-effective second line agent. However, information on potential interactions with drugs commonly used in immunosuppressed patients is lacking or contradictory. In this this article we review the metabolic pathway of dapsone with a focus on interactions and clinical significance particularly in patients with haematological malignancies. An understanding of this process should optimise the use of this agent.

Fluconazole resistance is not a predictor of poor outcome in patients with cryptococcosis

BACKGROUND

Cryptococcus isolates with high MICs to fluconazole are increasingly reported, and a potential clinical impact has been advocated. However, there are different methods to evaluate fluconazole MICs and comparative analysis among such techniques and their comprehensive correlation with clinical outcome are not available.

METHODS

Over a 13-year period (2000-2013), fluconazole MICs were determined for 62 cryptococcal isolates recovered from 22 patients with cryptococcosis using CLSI M27-A3, EUCAST, E test and Sensititre YeastOne, simultaneously. The relationship between the fluconazole MICs and the clinical outcome at week 10 was assessed in patients who received fluconazole as induction or maintenance therapy (n = 16).

RESULTS

The percentage of cryptococcal strains with MIC values ≥16 μg/mL according to different methods was CLSI 1.6%, EUCAST 16.1%, E test 31.6% and Sensititre YeastOne 53.2%. Among the 16 patients treated with fluconazole, no correlation between clinical outcome and any MIC value obtained with either method was observed. The only variable independently associated with a poor outcome was having a disseminated disease.

CONCLUSIONS

There is a weak correlation between fluconazole MICs against Cryptococcus spp. as determined by CLSI, EUCAST, E test and Sensititre YeastOne. Neither procedure could predict the clinical outcome of patients with cryptococcosis receiving fluconazole-based therapy. With present methods, fluconazole resistance in Cryptococcus may be clinically misleading.

Deletion of Aspergillus nidulans GDP-mannose transporters affects hyphal morphometry, cell wall architecture, spore surface character, cell adhesion, and biofilm formation

Systemic human fungal infections are increasingly common. Aspergillus species cause most of the airborne fungal infections. Life-threatening invasive aspergillosis was formerly found only in immune-suppressed patients, but recently some strains of A. fumigatus have become primary pathogens. Many fungal cell wall components are absent from mammalian systems, so they are potential drug targets. Cell-wall-targeting drugs such as echinocandins are used clinically, although echinocandin-resistant strains were discovered shortly after their introduction. Currently there are no fully effective anti-fungal drugs. Fungal cell wall glycoconjugates modulate human immune responses, as well as fungal cell adhesion, biofilm formation, and drug resistance. Guanosine diphosphate (GDP) mannose transporters (GMTs) transfer GDP-mannose from the cytosol to the Golgi lumen prior to mannosylation. Aspergillus nidulans GMTs are encoded by gmtA and gmtB. Here we elucidate the roles of A. nidulans GMTs. Strains engineered to lack either or both GMTs were assessed for hyphal and colonial morphology, cell wall ultrastructure, antifungal susceptibility, spore hydrophobicity, adherence and biofilm formation. The gmt-deleted strains had smaller colonies with reduced sporulation and with thicker hyphal walls. The gmtA deficient spores had reduced hydrophobicity and were less adherent and less able to form biofilms in vitro. Thus, gmtA not only participates in maintaining the cell wall integrity but also plays an important role in biofilm establishment and adherence of A. nidulans. These findings suggested that GMTs have roles in A. nidulans growth and cell-cell interaction and could be a potential target for new antifungals that target virulence determinants.

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.

Primary Gangrenous Cutaneous Mold Infections in a Patient With Cancer and Neutropenia

BACKGROUND

Opportunistic fungal infections caused by Aspergillus and Candida followed by infections with Fusarium, Rhizopus, Mucor, and Alternaria species are an important cause of morbidity and mortality in patients with hematological malignancies. Cutaneous mucormycosis infections are rare, and the incidence, outcomes, and factors associated with survival in the setting of hematological malignancies are not clear.

METHODS

A literature search was conducted for all cases of primary cutaneous mold infections in patients with hematological malignancy, of which 50 cases were found. Our case of a patient with a hematological malignancy who sustained a cat bite that in turn caused a primary cutaneous mold infection is also included.

RESULTS

In the 51 cases identified, 66.7% were neutropenic upon presentation, and 54.9% were male with an average age of 32 years. Aspergillus species (33.3%) was the most cited followed by Rhizopus species (19.6%). Overall mortality rate was 29.4% and was observed more frequently in patients with neutropenia (60.0%) and without surgical intervention (73.3%). Survival rate was higher (35.3%) for cases utilizing both antifungal and surgical intervention. The antifungal agent with the highest survival rate was amphotericin B and its formulations (58.8%).

CONCLUSIONS

Neutropenia within hematological malignancies demonstrate a risk for developing severe cutaneous fungal infections, of which primary cutaneous mucormycosis can carry significant mortality. Combination antifungal therapy and surgical debridement appears to be associated with higher survival outcomes and warrants further investigation.

Prevalence, clinical and economic burden of mucormycosis-related hospitalizations in the United States: a retrospective study

Background

Mucormycosis is a rare but devastating fungal infection primarily affecting immunocompromised patients such as those with hematological malignancy, bone marrow and solid organ transplantation, and patients with diabetes, and, even more rarely, immunocompetent patients. The objective of this study was to assess the prevalence and burden, both clinical and economic, of mucormycosis among hospitalized patients in the U.S.

Methods

This is a retrospective study using the Premier Perspective^TM Comparative Database, with more than 560 participating hospitals covering 104 million patients (January 2005-June 2014). All hospitalizations in the database were evaluated for the presence of mucormycosis using either an ICD-9 code of 117.7 or a positive laboratory result for Mucorales. Hospitalizations were further required to have prescriptions of amphotericin B or posaconazole to be considered as mucormycosis-related hospitalizations. The prevalence of mucormycosis-related hospitalizations among all hospital discharges was estimated. Mortality rate at discharge, length of hospital stay, and readmission rates at 1 and 3 months were evaluated among mucormycosis-related hospitalizations. Cost per hospital stay and average per diem cost (inflated to 2014 USD) were reported.

Results

The prevalence of mucormycosis-related hospitalizations was estimated as 0.12 per 10,000 discharges during January 2005-June 2014. It increased to 0.16 per 10,000 discharges if the definition of mucormycosis was relaxed to not require the use of amphotericin B or posaconazole. The median length of stay was 17 days, with 23% dead at discharge; readmission rates were high, with 30 and 37% of patients readmitted within one and three months of discharge, respectively. The average cost per hospital stay was $112,419, and the average per diem cost was $4,096.

Conclusions

The study provides a recent estimate of the prevalence and burden of mucormycosis among hospitalized patients. The high clinical and economic burden associated with mucormycosis highlights the importance of establishing active surveillance and optimizing prophylactic and active treatment in susceptible patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2023-z) contains supplementary material, which is available to authorized users.

Aspergillosis and stem cell transplantation: An overview of experimental pathogenesis studies

Invasive aspergillosis is a life-threatening infection caused by the opportunistic filamentous fungus Aspergillus fumigatus. Patients undergoing haematopoietic stem cell transplant (HSCT) for the treatment of hematological malignancy are at particularly high risk of developing this fatal infection. The susceptibility of HSCT patients to infection with A. fumigatus is a consequence of a complex interplay of both fungal and host factors. Here we review our understanding of the host-pathogen interactions underlying the susceptibility of the immunocompromised host to infection with A. fumigatus with a focus on the experimental validation of fungal and host factors relevant to HSCT patients. These include fungal factors such as secondary metabolites, cell wall constituents, and metabolic adaptations that facilitate immune evasion and survival within the host microenvironment, as well as the innate and adaptive immune responses involved in host defense against A. fumigatus.

Reduction in incidence of invasive fungal infection in patients receiving allogeneic stem cell transplantation using combined diagnostic-driven approach and itraconazole oral solution

Invasive fungal infections are an important cause of morbidity and mortality after allogeneic haematopoietic stem cell transplantation. We evaluated, in our allogeneic stem cell transplant patients, the effect on the incidence of invasive fungal infection during neutropenia of a strategy combining a diagnostic-driven approach with chemoprophylaxis during higher risk periods of graft vs. host disease and prolonged neutropenia, using itraconazole oral solution with parenteral voriconazole bridging. One hundred and thirty patients admitted for allogeneic stem cell transplantation within two predefined 20 month periods were included in the study. Data for all patients were collected prospectively. Implementation of the protocol resulted in the administration of more prophylactic antifungals to more patients. Following implementation, there was a non-significant decrease in the overall number of invasive fungal infections (IFI) [11 of 65 patients (17.2%) vs. 4 of 65 patients (6.2%, P = 0.051)], as well as in the occurrence of invasive mould infections [8 of 65 patients (12.5%) vs. 2 of 65 patients (3.1%, P = 0.054)]. Survival rates at three and 6 months were not significantly affected. A combined diagnostic-driven approach and antifungal prophylaxis with oral itraconazole and an intravenous voriconazole bridging protocol, was associated with a reduced, albeit non-statistically significant, number of IFI in our medical centre.

Septic arthritis in immunocompetent and immunosuppressed hosts

Septic arthritis has long been considered an orthopedic emergency. Historically, Neisseria gonorrhoeae and Staphylococcus aureus have been the most common causes of septic arthritis worldwide but in the modern era of biological therapy and extensive use of prosthetic joint replacements, the spectrum of microbiological causes of septic arthritis has widened considerably. There are also new approaches to diagnosis but therapy remains a challenge, with a need for careful consideration of a combined medical and surgical approach in most cases.

A long-term survivor of disseminated Aspergillus and mucorales infection: an instructive case

Invasive fungal infections remain major causes of infection-related mortality in hematopoietic stem cell transplantation (HSCT) patients. Mixed infections and multiple organ involvement have been reported in these patients. Here, we report a case of mixed Aspergillus and Mucorales infection involving the lungs, brain, spleen and bone in a HSCT patient with relapsed acute myeloid leukemia, who finally improved with triple antifungal therapy and neurosurgical evacuation of brain abscesses. She was put on lifelong secondary prophylaxis with posaconazole with excellent compliance and no sign of toxicity despite over 10 years of drug administration. Serial galactomannan measurements and positron emission tomography/computed tomography were used and were helpful for disease activity monitoring. This is an instructive case of long-term survival after a severe combined mould infection.

A review on ethnobotany, phytochemistry and pharmacology of plant genus C aralluma R. Br

Objectives

C aralluma is a xerophytic genus used as traditional medicine for the treatment of diabetes, inflammation, leprosy, obesity and rheumatism. Objectives of this review are to establish a relationship between traditional uses and scientific studies by critically evaluating the available fragmented literature on ethnobotany, pharmacology, phytochemistry and toxicology of genus Caralluma.

Key findings

Ethnomedical uses of Caralluma have been recorded from various countries such as China, India, Iran and Pakistan for six major classes of diseases including diabetes and gastrointestinal disorders. This review indicated the efficacy of genus Caralluma in several in vitro and in vivo pharmacological properties such as antimicrobial, antioxidant and anticancer activity. These bioactivity might be due to the presence of certain classes of compounds in genus Caralluma including pregnane glycosides, flavonoid glycosides and flavones.

Summary

Traditional uses and scientific evaluation of Caralluma indicates that it is one of the most widely used genus in some parts of the world. Further studies on the structural activity relationship of some of the isolated compound may improve their biological potency as well as scientific exploitation of traditional uses of the genus.

Comparison and temporal trends of three groups with cryptococcosis: HIV-infected, solid organ transplant, and HIV-negative/non-transplant

BACKGROUND

The Infectious Disease Society of America (IDSA) 2010 Clinical Practice Guidelines for the management of cryptococcosis outlined three key populations at risk of disease: (1) HIV-infected, (2) transplant recipient, and (3) HIV-negative/non-transplant. However, direct comparisons of management, severity and outcomes of these groups have not been conducted.

METHODOLOGY/PRINCIPAL FINDINGS

Annual changes in frequency of cryptococcosis diagnoses, cryptococcosis-attributable mortality and mortality were captured. Differences examined between severe and non-severe disease within the context of the three groups included: demographics, symptoms, microbiology, clinical management and treatment. An average of nearly 15 patients per year presented at Duke University Medical Center (DUMC) with cryptococcosis. Out of 207 study patients, 86 (42%) were HIV-positive, 42 (20%) were transplant recipients, and 79 (38%) were HIV-negative/non-transplant. HIV-infected individuals had profound CD4 lymphocytopenia and a majority had elevated intracranial pressure. Transplant recipients commonly (38%) had renal dysfunction. Nearly one-quarter (24%) had their immunosuppressive regimens stopped or changed. The HIV-negative/non-transplant population reported longer duration of symptoms than HIV-positive or transplant recipients and 28% (22/79) had liver insufficiency or underlying hematological malignancies. HIV-positive and HIV-negative/non-transplant patients accounted for 89% of severe disease cryptococcosis-attributable deaths and 86% of all-cause mortality.

CONCLUSIONS/SIGNIFICANCE

In this single-center study, the frequency of cryptococcosis did not change in the last two decades, although the underlying case mix shifted (fewer HIV-positive cases, stable transplant cases, more cases with neither). Cryptococcosis had a relatively uniform and informed treatment strategy, but disease-attributable mortality was still common.

Effects of carbapenems and their combination with amikacin on murine gut colonisation by Candida albicans

Carbapenems are broad-spectrum antibiotics increasingly used for the treatment of severe infections. We evaluated the effects of four carbapenems given as monotherapies or in combination with amikacin on the level of gastrointestinal colonisation by Candida albicans in a previously established mouse model. Adult male Crl : CD1 (ICR) BR mice were fed chow containing C. albicans or regular chow. The mice fed with Candida chow had their gut colonised by the yeast. Both groups were subsequently given imipenem, meropenem, ertapenem, doripenem or their combination with amikacin or normal saline subcutaneously for 10 days. Stool cultures were performed immediately before, at the end and 1 week after discontinuation of treatment. Candida-colonised mice treated with the antibiotics had higher counts of the yeast in their stools than control C. albicans-colonised animals treated with saline. All four carbapenems and their combination with amikacin caused a significant increase in C. albicans concentration. Mice fed regular chow and treated with the study antibiotics or saline did not have any Candida in their stools. Dissemination of Candida was not detected in any animal. These data suggest that carbapenems and carbapenem plus amikacin induce substantial increases in the murine intestinal concentration of C. albicans.

Laboratory diagnostics of invasive fungal infections: an overview with emphasis on molecular approach

Although invasive fungal diseases (IFDs) are relatively rare, they have become an increasingly common life-threatening complication in a variety of critically ill patients. Due to changes in treatment strategies, patterns of IFDs have changed substantially as well. Yeast infections have shifted toward a higher proportion of non-albicans Candida species, but their overall incidence has remained stable. In contrast, IFDs caused by molds, including particularly various species of Aspergillus, Fusarium, and Mucorales, have increased in number. In view of the growing incidence and the high mortality rates of IFDs, accurate diagnostic techniques permitting timely onset of adequate antifungal treatment are of paramount importance. Although conventional approaches such as microscopy, cultivation, histopathological examination, and imaging methods still represent the gold standard, the diagnosis remains difficult because of limited sensitivity and specificity. Noninvasive and culture-independent diagnostic techniques, including fungal antigen detection, and different molecular-based techniques are becoming increasingly important. Of the fungal surrogate markers such as cell wall components, galactomannan and (1,3)-β-D-glucan by commercially available diagnostic kits have become widely used, but the results are still controversial. A plethora of PCR-based diagnostic methods targeting different gene regions and exploiting a variety of amplicon detection tools have been published. Molecular assays have the capacity to overcome the limitations of other diagnostic approaches, but the current lack of methodological standardization and validation, together with not always clear interpretation of the results, has prevented broad application in the clinical setting.

Weekly liposomal amphotericin B as secondary prophylaxis for invasive fungal infections in patients with hematological malignancies

There have been no published studies evaluating the efficacy and safety of weekly liposomal amphotericin B as secondary prophylaxis in leukemic patients with invasive fungal infections (IFIs). We found in a retrospective review of our experience with 14 such patients admitted from 2003-2009 that the use of this approach was associated with frequent relapse of IFIs (36%) and kidney injury (36%).

The occurrence and prevention of foodborne disease in vulnerable people

In developed countries, such as the United Kingdom and the United States, between 15% and 20% of the population show greater susceptibility than the general population to foodborne disease. This proportion includes people with primary immunodeficiency, patients treated with radiation or with immunosuppressive drugs for cancer and diseases of the immune system, those with acquired immune-deficiency syndrome and diabetics, people suffering from liver or kidney disease or with excessive iron in the blood, pregnant women, infants, and the elderly. Malnutrition and use of antacids, particularly proton-pump inhibitors, also increase susceptibility. We review the occurrence of infection by foodborne pathogens in these groups of people and measures to prevent infection. The nature and use of low microbial diets to reduce the risk of foodborne disease in immunocompromised patients are very variable. Diets for vulnerable people in care should exclude higher-risk foods, and vulnerable people in the community should receive clear advice about food safety, in particular avoidance of higher-risk foods and substitution of safer, nutritious foods.

Evaluation of Luminex xTAG fungal analyte-specific reagents for rapid identification of clinically relevant fungi

Invasive fungal infections (IFI) remain a serious threat to immunocompromised hosts. Current diagnostic methods, including fungal culture and antigen detection, are slow and often lack specificity. Rapid diagnostic tools with increased sensitivity and specificity could improve the care of patients with IFI. Recently, Luminex Molecular Diagnostics (Toronto, Canada) developed 23 analyte-specific reagents (ASRs) for the detection of the most common clinically relevant fungi. This study's objective was to evaluate the sensitivity and specificity of a subset of these ASRs for fungal isolates and clinical specimens. Previously characterized fungal and bacterial isolates (n = 110), blood culture specimens (n = 34), and respiratory specimens (n = 44) were tested using either a Candida 7-plex panel (Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, Candida lusitaniae, Candida guilliermondii, and Candida krusei) or a mold 11-plex panel (Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Scedosporium prolificans, Scedosporium apiospermum, Fusarium oxysporum/Fusarium solani, Rhizopus arrhizus, Rhizopus microsporus, Mucor indicus, and Cunninghamella bertholletiae). The Candida 7-plex panel correctly identified all Candida isolates as confirmed by fungal culture and biochemical tests, for a sensitivity and specificity of 100%. The mold 11-plex panel correctly identified all mold isolates tested except for A. niger. Fungal isolates of Rhizopus and Mucor species were not detected, either, although they could represent species other than those targeted by the ASRs. Further evaluation will be necessary to confirm the sensitivities of some of the mold ASRs. Implementation of these ASRs will allow same-day detection of fungal DNA in clinical specimens.

Mesenchymal stromal cells for treatment of steroid-refractory GvHD: a review of the literature and two pediatric cases

Severe acute graft versus host disease (GvHD) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation. Human mesenchymal stromal cells (MSCs) play an important role in endogenous tissue repair and possess strong immune-modulatory properties making them a promising tool for the treatment of steroid-refractory GvHD. To date, a few reports exist on the use of MSCs in treatment of GvHD in children indicating that children tend to respond better than adults, albeit with heterogeneous results.

We here present a review of the literature and the clinical course of two instructive pediatric patients with acute steroid-refractory GvHD after haploidentical stem cell transplantation, which exemplify the beneficial effects of third-party transplanted MSCs in treatment of acute steroid-refractory GvHD. Moreover, we provide a meta-analysis of clinical studies addressing the outcome of patients with steroid-refractory GvHD and treatment with MSCs in adults and in children (n = 183; 122 adults, 61 children). Our meta-analysis demonstrates that the overall response-rate is high (73.8%) and confirms, for the first time, that children indeed respond better to treatment of GvHD with MSCs than adults (complete response 57.4% vs. 45.1%, respectively).

These data emphasize the significance of this therapeutic approach especially in children and indicate that future prospective studies are needed to assess the reasons for the observed differential response-rates in pediatric and adult patients.

[Cost effectiveness of posaconazole versus fluconazole/itraconazole in the prophylactic treatment of invasive fungal infections in Mexico]

Cost effectiveness of posaconazole versus fluconazole/itraconazole therapy in the prophylaxis against invasive fungal Infections among high-risk neutropenic patients in Mexico.

OBJECTIVE

To estimate the cost effectiveness and long-term combined effects of Posaconazole versus fluconazole/itraconazole (standard azole) therapy in the prophylaxis against invasive fungal Infections among high-risk neutropenic patients in Mexico.

METHODS

A previously validated Markov model was used to compare the projected lifetime costs and effects of two theoretical groups of patients, one receiving Posaconazole and the other receiving standard azole. The model estimates total costs, numbers of IFIs, and QALY per patient in each prophylaxis group. To extrapolate trial results to a lifetime horizon, the model was extended with one-month Markov cycles in which mortality risk is specific to the underlying disease. Data on the probabilities of IFI were obtained from Study Protocol PO1899. Drug costs were taken from average wholesale drug reports for 2009. Cost and health effects were discounted at 5% according to the Mexican guideline. The analysis was conducted from the Mexican healthcare perspective using 2008 unit cost prices.

RESULTS

Our model projects an accumulated cost to the Mexican healthcare system per patient receiving the Posaconazol regimen of $US 5,634 compared to $US 7,463 for the standard azole regimen. The accumulated discounted effect is 3.13 LY or 2.25 QALYs per patient receiving Posaconazol, compared to 2.96 LY or 2.13 QALYs per patient receiving standard azole. Posaconazol remained the dominant strategy across each scenario. Probabilistic sensitivity analysis tested numerous assumptions about the model cost and efficacy parameters and found that the results were robust to most changes.

CONCLUSION

Posaconazole provides modest incremental benefits compared with standard azole therapy in the prophylaxis against IFIs among high-risk neutropenic patients. Routine Posaconazole use appears a cost saving when the likelihood of IFIs or the cost of treatment medications is high.

Infections in liver transplant recipients

Liver transplantation is a standard life-saving procedure for the treatment of many end-stage liver diseases. The success of this procedure may be limited by infectious complications. In this article, we review the contemporary state of infectious complications during the post-operative period, with particular emphasis on those that occur most commonly during the first 6 mo after liver transplantation. Bacteria, and less commonly Candida infections, remain the predominant pathogens during the immediate post-operative period, especially during the first month, and infections caused by drug-resistant strains are emerging. Infections caused by cytomegalovirus and Aspergillus sp. present clinically during the "opportunistic" period characterized by intense immunosuppression. As newer potent immunosuppressive therapies with the major aim of reducing allograft rejection are developed, one potential adverse effect is an increase in certain infections. Hence, it is essential for liver transplant centers to have an effective approach to prevention that is based on predicted infection risk, local antimicrobial resistance patterns, and surveillance. A better understanding of the common and most important infectious complications is anticipated to lead to improvements in quality of life and survival of liver transplant recipients.

[Guidelines for the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). 2011 Update]

The guidelines on the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) are presented. These recommendations are focused on four clinical categories: oncology-haematology patients, solid organ transplant recipients, patients admitted to intensive care units, and children. An extensive review is made of therapeutical advances and scientific evidence in these settings. These guidelines have been prepared according the SEIMC consensus rules by a working group composed of specialists in infectious diseases, clinical microbiology, critical care medicine, paediatrics and oncology-haematology. Specific recommendations on the prevention of fungal infections in these patients are included.

Invasive Candida infections in solid organ transplant recipient children

Solid organ transplantation (SOT) is now an accepted therapy for many end-stage organ disorders and fungal infections are the principal cause of infection-related mortality in SOT recipients. Among invasive fungal infections, Candida species are the most common pathogens identified, associated with high mortality rates. The epidemiology and clinical manifestations of Candida infections vary with the type of organ transplantation. This article reviews invasive Candida infections in pediatric SOT recipients.

Intravenous ascorbic acid to prevent and treat cancer-associated sepsis?

The history of ascorbic acid (AA) and cancer has been marked with controversy. Clinical studies evaluating AA in cancer outcome continue to the present day. However, the wealth of data suggesting that AA may be highly beneficial in addressing cancer-associated inflammation, particularly progression to systemic inflammatory response syndrome (SIRS) and multi organ failure (MOF), has been largely overlooked. Patients with advanced cancer are generally deficient in AA. Once these patients develop septic symptoms, a further decrease in ascorbic acid levels occurs. Given the known role of ascorbate in: a) maintaining endothelial and suppression of inflammatory markers; b) protection from sepsis in animal models; and c) direct antineoplastic effects, we propose the use of ascorbate as an adjuvant to existing modalities in the treatment and prevention of cancer-associated sepsis.

In vitro interactions among echinocandins against Aspergillus fumigatus: lack of concordance among methods

Drug combinations are increasingly being explored as a means of improving outcomes in cases of invasive aspergillosis. However, the optimal methods for assessing in vitro drug combinations are unclear. We investigated whether echinocandin drug combinations have potentially useful interactions against Aspergillus fumigatus. We explored the in vitro interactions of three echinocandins (caspofungin [CSP], anidulafingin [ANF], and micafungin [MCF]) by three methods, i.e., (i) checkerboard assay, (ii) disk diffusion assay, and (iii) E-test/agar dilution. The checkerboard experiments revealed different interactions between echinocandin pairs depending on the drug combination tested. Specifically, the combination of CSF and either ANF or MCF yielded a fractional inhibitory concentration (FIC) index range of 0.15-2.0. Whereas the combination of MCF and ANF yielded an FIC index range of 0.19-0.31, consistent with synergistic interaction. In contrast, all echinocandin pairs appeared indifferent by the disk diffusion method. Moreover, the combination of MCF and ANF appeared antagonistic when the two drugs were tested using the E-test/agar dilution method with both the FKS1 wild-type and echinocandin-resistant fks1 mutant strains. Our results highlight methodological problems inherent in in vitro antifungal combination testing. We did not find compelling evidence of inter-echinocandin synergy that could serve as a basis for further in vivo experimentation.