Successful control of disseminated Scedosporium prolificans infection with a combination of voriconazole and terbinafine

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

Deciphering Unexpected Vascular Locations of Scedosporium spp. and Lomentospora prolificans Fungal Infections, France

Scedosporium spp. and Lomentospora prolificans are emerging non-Aspergillus filamentous fungi. The Scedosporiosis/lomentosporiosis Observational Study we previously conducted reported frequent fungal vascular involvement, including aortitis and peripheral arteritis. For this article, we reviewed 7 cases of Scedosporium spp. and L. prolificans arteritis from the Scedosporiosis/lomentosporiosis Observational Study and 13 cases from published literature. Underlying immunosuppression was reported in 70% (14/20) of case-patients, mainly those who had solid organ transplants (10/14). Osteoarticular localization of infection was observed in 50% (10/20) of cases; infections were frequently (7/10) contiguous with vascular infection sites. Scedosporium spp./Lomentospora prolificans infections were diagnosed in 9 of 20 patients ≈3 months after completing treatment for nonvascular scedosporiosis/lomentosporiosis. Aneurysms were found in 8/11 aortitis and 6/10 peripheral arteritis cases. Invasive fungal disease--related deaths were high (12/18 [67%]). The vascular tropism of Scedosporium spp. and L. prolificans indicates vascular imaging, such as computed tomography angiography, is needed to manage infections, especially for osteoarticular locations.

Fusariosis in Mexico: A 10-year retrospective series

Fusarium species represent an opportunistic fungal pathogen. The data in Mexico about Fusarium infections in humans are scarce. Here, we present a retrospective series of patients with a confirmed diagnosis of fusariosis in eight different hospitals in Mexico from January 2010 to December 2019. The diagnosis of proven fusariosis was made according to the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium (EORT/MSG) criteria. A total of 49 cases were identified in our series. Most patients had burn injuries (49%), and 37% had hematological malignancies. Most patients had fire injuries (40%), followed by electric injuries (8%), febrile neutropenia (10%), and pancytopenia (6%). Patients had skin and soft tissue involvement in 49%, followed by blood culture isolation and biopsies from different sites of the body (lung, sinuses, bone tissue, and eyes). Febrile neutropenia (10%) and fungemia (8%) were the most common clinical syndromes in immunosuppressed patients. Most patients received monotherapy (67%), where voriconazole was used in 30% of the cases, followed by conventional amphotericin B (16%), and lipidic formulations of amphotericin B in 10% (either liposomal amphotericin B or amphotericin B lipid complex). Combination therapy was used in 20% of the cases, and the most common combination therapy was triazole plus any lipidic formulation of amphotericin B (10%). Mortality related to Fusarium infection occurred in 22% of patients. Fusariosis is a serious threat. Burn injuries and hematologic malignancies represent the most common causes of infection in this small series from Mexico.

Unusual Fungal Endocarditis Causing Disseminated Infection After Renal Transplant

Fungal endocarditis is a relatively uncommon disease; it mostly affects those with intracardiac devices and those with compromised immune systems. Scedosporium apiospermum (S. apiospermum), the asexual state of Pseudoallescheria boydii, has become increasingly reported as an opportunistic pathogen. These filamentous fungi present in soil, sewage, and polluted waters, and was previously recognized to cause human infection after their inhalation or traumatic subcutaneous implantation. In immunocompetent individuals, it usually causes localized diseases depending on the site of entry such as skin mycetoma. However, in immunocompromised hosts, the fungus species appear to disseminate and cause invasive infections, frequently reported to be life-threatening with poor response to antifungal medications. S. apiospermum invasive endocarditis remains a rare complication, mostly cited in immunocompetent hosts with prosthetic cardiac valves or other intracardiac devices and severely immunocompromised patients with hematologic neoplasia. Herein, we describe the case of a renal transplant patient on immunosuppressive medications who presented with S. apiospermum fungal septic infection that invaded the left ventricular outflow tract (LVOT) causing endocarditis with disseminated infection and resulted in poor clinical outcome.

Evolution of antifungals for invasive mold infections in immunocompromised hosts, then and now

INTRODUCTION

The current armamentarium of antifungal agents for invasive mold infections (IMI) has dramatically improved over the last 50 years. Existing therapies are, however, associated with toxicities, drug interactions, and in some cases, therapeutic failures. Novel antifungals are needed to address the increasing prevalence of IMI and the growing threat of antifungal resistance.

AREAS COVERED

We review the history and development of the most commonly used antifungals. We discuss the current consensus guidelines and supporting data for treatment of invasive mold infection (IMI), the role of susceptibility testing, and the niche that novel antifungals could fill. We review the current data for aspergillosis, mucormycosis, and hyalohyphomycosis.

EXPERT OPINION

Robust clinical trial data demonstrating the relative effectiveness of our current antifungal agents for treating IMI outside of A. fumigatus remains limited. Clinical trials are urgently needed to delineate the relationship between MICs and clinical outcomes for existing agents and to better evaluate the invitro and in-vivo aspects of antifungal synergy. Continued international multicenter collaboration and standardized clinical endpoints for trials evaluating both existing and new agents is necessary to advance the field.

Lomentospora prolificans Disseminated Infections: A Systematic Review of Reported Cases

BACKGROUND

Lomentospora prolificans, a rare, highly virulent filamentous fungus with high rates of intrinsic resistance to antifungals, has been associated with different types of infections in immunocompromised as well as immunocompetent individuals.

OBJECTIVE

To systematically address all relevant evidence regarding L. prolificans disseminated infections in the literature.

METHODS

We searched Medline via PubMed and Scopus databases through July 2022. We performed a qualitative synthesis of published articles reporting disseminated infections from L. prolificans in humans.

RESULTS

A total of 87 studies describing 142 cases were included in our systematic review. The pathogen was most frequently reported in disseminated infections in Spain (n = 47), Australia (n = 33), the USA (n = 21), and Germany (n = 10). Among 142 reported cases, 48.5% were males. Underlying conditions identified for the majority of patients included malignancy (72.5%), hemopoietic stem cell transplantation (23.2%), solid organ transplantation (16%), and AIDS (2%). Lungs, central nervous system, skin, eyes, heart and bones/joints were the most commonly affected organs. Neutropenia was recorded in 52% of patients. The mortality rate was as high as 87.3%.

CONCLUSIONS

To the best of our knowledge, this is the first systematic review conducted on disseminated infections due to this rare microorganism. Physicians should be aware that L. prolificans can cause a diversity of infections with high mortality and primarily affects immunocompromised and neutropenic patients.

Osteoarticular Mycoses

Osteoarticular mycoses are chronic debilitating infections that require extended courses of antifungal therapy and may warrant expert surgical intervention. As there has been no comprehensive review of these diseases, the International Consortium for Osteoarticular Mycoses prepared a definitive treatise for this important class of infections. Among the etiologies of osteoarticular mycoses are Candida spp., Aspergillus spp., Mucorales, dematiaceous fungi, non-Aspergillus hyaline molds, and endemic mycoses, including those caused by Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species. This review analyzes the history, epidemiology, pathogenesis, clinical manifestations, diagnostic approaches, inflammatory biomarkers, diagnostic imaging modalities, treatments, and outcomes of osteomyelitis and septic arthritis caused by these organisms. Candida osteomyelitis and Candida arthritis are associated with greater events of hematogenous dissemination than those of most other osteoarticular mycoses. Traumatic inoculation is more commonly associated with osteoarticular mycoses caused by Aspergillus and non-Aspergillus molds. Synovial fluid cultures are highly sensitive in the detection of Candida and Aspergillus arthritis. Relapsed infection, particularly in Candida arthritis, may develop in relation to an inadequate duration of therapy. Overall mortality reflects survival from disseminated infection and underlying host factors.

Lomentospora prolificans: An Emerging Opportunistic Fungal Pathogen

Lomentospora prolificans is an emerging opportunistic pathogen that primarily affects immunocompromised individuals leading to disseminated disease with high mortality rates while also causing infections in healthy populations. Successful recovery from infection is difficult due to high rates of intrinsic resistance to antifungals. Rapid and readily available diagnostic methods, aggressive surgical debridement wherever appropriate, and effective and timely antifungal treatment are the pillars for successful management. Future research will need to clarify the environmental niche of the fungus, further investigate the pathophysiology of infection and define species-specific therapeutic targets.

Consensus guidelines for the diagnosis and management of invasive fungal disease due to moulds other than Aspergillus in the haematology/oncology setting, 2021

Invasive fungal disease (IFD) due to moulds other than Aspergillus is a significant cause of mortality in patients with malignancies or post haemopoietic stem cell transplantation. The current guidelines focus on the diagnosis and management of the common non-Aspergillus moulds (NAM), such as Mucorales, Scedosporium species (spp.), Lomentospora prolificans and Fusarium spp. Rare but emerging NAM including Paecilomyces variotii, Purpureocillium lilacinum and Scopulariopsis spp. are also reviewed. Culture and histological examination of tissue biopsy specimens remain the mainstay of diagnosis, but molecular methods are increasingly being used. As NAM frequently disseminate, blood cultures and skin examination with biopsy of any suspicious lesions are critically important. Treatment requires a multidisciplinary approach with surgical debridement as a central component. Other management strategies include control of the underlying disease/predisposing factors, augmentation of the host response and the reduction of immunosuppression. Carefully selected antifungal therapy, guided by susceptibility testing, is critical to cure. We also outline novel antifungal agents still in clinical trial which offer substantial potential for improved outcomes in the future. Paediatric recommendations follow those of adults. Ongoing epidemiological research, improvement in diagnostics and the development of new antifungal agents will continue to improve the poor outcomes that have been traditionally associated with IFD due to NAM.

In vitro antifungal combination of terbinafine with itraconazole against isolates of Trichophyton spp

Terbinafine is used as first-line therapy for dermatophytosis, but the incidence of terbinafine-resistance is increasing. Combination of terbinafine with itraconazole was tested by checkerboard based on the EUCAST methodology for antifungal susceptibility testing against 9 terbinafine-susceptible and 7 terbinafine-resistant clinical isolates of Trichophyton spp. from India. Synergistic interactions were observed for 4/9 of the susceptible isolates with fractional inhibitory concentration index (FICI) values of 0.3125 to 0.5 and for 4/7 of the resistant isolates with FICI values of 0.032 to 0.3125.

Global guideline for the diagnosis and management of rare mould infections: an initiative of the European Confederation of Medical Mycology in cooperation with the International Society for Human and Animal Mycology and the American Society for Microbiology

With increasing numbers of patients needing intensive care or who are immunosuppressed, infections caused by moulds other than Aspergillus spp or Mucorales are increasing. Although antifungal prophylaxis has shown effectiveness in preventing many invasive fungal infections, selective pressure has caused an increase of breakthrough infections caused by Fusarium, Lomentospora, and Scedosporium species, as well as by dematiaceous moulds, Rasamsonia, Schizophyllum, Scopulariopsis, Paecilomyces, Penicillium, Talaromyces and Purpureocillium species. Guidance on the complex multidisciplinary management of infections caused by these pathogens has the potential to improve prognosis. Management routes depend on the availability of diagnostic and therapeutic options. The present recommendations are part of the One World-One Guideline initiative to incorporate regional differences in the epidemiology and management of rare mould infections. Experts from 24 countries contributed their knowledge and analysed published evidence on the diagnosis and treatment of rare mould infections. This consensus document intends to provide practical guidance in clinical decision making by engaging physicians and scientists involved in various aspects of clinical management. Moreover, we identify areas of uncertainty and constraints in optimising this management.

Fatal recurrent disseminated Lomentospora prolificans infection during autologous hematopoietic stem cell transplantation: A case report and review, and discussion on the importance of prolonged neutropenia

Infections with Scedosporium and Lomentospora species, in particular Lomentospora (previously Scedosporium) prolificans, are nearly universally fatal and rapidly-progressive in the transplant population. We report a case of a patient with diffuse large B-cell lymphoma undergoing myelosuppressive chemotherapy who developed disseminated L. prolificans infection which afterward persisted in his knee joint. The infection was treated with early empiric triple antifungal therapy tailored to synergy studies, growth factors to quickly resolve neutropenia, and aggressive debridement (where possible) of infection sites, including amputation. He achieved an 11-month remission until undergoing autologous hematopoietic stem cell transplantation with deep myelosuppression, wherein recrudescent L. prolificans infection occurred, causing death. We highlight the importance of early treatment, synergy studies, and especially recovery of neutropenia in treating this devastating condition.

Antibiofilm activity of antifungal drugs, including the novel drug olorofim, against Lomentospora prolificans

OBJECTIVES

Patients with immunodeficiency or cystic fibrosis frequently suffer from respiratory fungal infections. In particular, biofilm-associated fungi cause refractory infection manifestations, linked to increased resistance to anti-infective agents. One emerging filamentous fungus is Lomentospora prolificans. Here, the biofilm-formation capabilities of L. prolificans isolates were investigated and the susceptibility of biofilms to various antifungal agents was analysed.

METHODS

Biofilm formation of L. prolificans (n = 11) was estimated by crystal violet stain and antibiofilm activity was additionally determined via detection of metabolically active biofilm using an XTT assay. Amphotericin B, micafungin, voriconazole and olorofim were compared with regard to their antibiofilm effects when added prior to adhesion, after adhesion and on mature and preformed fungal biofilms. Imaging via confocal laser scanning microscopy was carried out to demonstrate the effect of drug treatment on the fungal biofilm.

RESULTS

Antibiofilm activities of the tested antifungal agents were shown to be most effective on adherent cells whilst mature biofilm was the most resistant. The most promising antibiofilm effects were detected with voriconazole and olorofim. Olorofim showed an average minimum biofilm eradication concentration (MBEC) of 0.06 mg/L, when added prior to and after adhesion. The MBECs of voriconazole were ≤4 mg/L. On mature biofilm the MBECs of olorofim and voriconazole were higher than the previously determined MICs against planktonic cultures. In contrast, amphotericin B and especially micafungin did not exhibit sufficient antibiofilm activity against L. prolificans.

CONCLUSIONS

To our knowledge, this is the first study demonstrating the antibiofilm potential of olorofim against the human pathogenic fungus L. prolificans.

Recent developments in less known and multi-resistant fungal opportunists

Fungal infections have increased in recent years due to host factors, such as oncohaematological and transplant-related disorders, immunosuppressive therapy, and AIDS. Additionally, molecular and proteomic facilities have become available to identify previously unrecognizable opportunists. For these reasons, reports on less-known and recalcitrant mycoses, such as those caused by black fungi, hyaline filamentous fungi, coelomycetes, Mucorales, and non-Candida yeasts have emerged. In this review, novel taxonomy in these groups, which often are multi-resistant to one or several classes of antifungals, is discussed. Clinical presentations, diagnosis and current treatment of some major groups are summarised.

The Host Immune Response to Scedosporium/Lomentospora

Infections caused by the opportunistic pathogens Scedosporium/Lomentospora are on the rise. This causes problems in the clinic due to the difficulty in diagnosing and treating them. This review collates information published on immune response against these fungi, since an understanding of the mechanisms involved is of great interest in developing more effective strategies against them. Scedosporium/Lomentospora cell wall components, including peptidorhamnomannans (PRMs), α-glucans and glucosylceramides, are important immune response activators following their recognition by TLR2, TLR4 and Dectin-1 and through receptors that are yet unknown. After recognition, cytokine synthesis and antifungal activity of different phagocytes and epithelial cells is species-specific, highlighting the poor response by microglial cells against L. prolificans. Moreover, a great number of Scedosporium/Lomentospora antigens have been identified, most notably catalase, PRM and Hsp70 for their potential medical applicability. Against host immune response, these fungi contain evasion mechanisms, inducing host non-protective response, masking fungal molecular patterns, destructing host defense proteins and decreasing oxidative killing. In conclusion, although many advances have been made, many aspects remain to be elucidated and more research is necessary to shed light on the immune response to Scedosporium/Lomentospora.

Amphotericin B and Other Polyenes-Discovery, Clinical Use, Mode of Action and Drug Resistance

Although polyenes were the first broad spectrum antifungal drugs on the market, after 70 years they are still the gold standard to treat a variety of fungal infections. Polyenes such as amphotericin B have a controversial image. They are the antifungal drug class with the broadest spectrum, resistance development is still relatively rare and fungicidal properties are extensive. Yet, they come with a significant host toxicity that limits their use. Relatively recently, the mode of action of polyenes has been revised, new mechanisms of drug resistance were discovered and emergent polyene resistant species such as Candida auris entered the picture. This review provides a short description of the history and clinical use of polyenes, and focusses on the ongoing debate concerning their mode of action, the diversity of resistance mechanisms discovered to date and the most recent trends in polyene resistance development.

Antifungal Susceptibility Profiles and Drug Resistance Mechanisms of Clinical Lomentospora prolificans Isolates

Lomentospora prolificans is an opportunistic fungal pathogen with low susceptibility to current antifungal drugs. Here, we tested the in vitro susceptibility of 8 drugs against 42 clinical L. prolificans isolates. All isolates showed high MICs to voriconazole (MIC₉₀>16 μg/ml), itraconazole (MIC₉₀>16 μg/ml), posaconazole (MIC₉₀>16 μg/ml), isavuconazole (MIC₉₀>16 μg/ml), amphotericin B (MIC₉₀>16 μg/ml), and terbinafine (MIC₉₀>64 μg/ml) and high minimum effective concentrations (MECs) to micafungin (MEC₉₀>8 μg/ml), with the exception of miltefosine showing an MIC₉₀ value of 4 μg/ml. We examined six different in vitro drug combinations and found that the combination of voriconazole and terbinafine achieved the most synergistic effort against L. prolificans We then annotated the L. prolificans whole genome and located its Cyp51 and Fks1 genes. We completely sequenced the two genes to determine if any mutation would be related to azole and echinocandin resistance in L. prolificans We found no amino acid changes in Cyp51 protein and no tandem repeats in the 5' upstream region of the Cyp51 gene. However, we identified three intrinsic amino acid residues (G138S, M220I, and T289A) in the Cyp51 protein that were linked to azole resistance. Likewise, two intrinsic amino acid residues (F639Y, W695F) that have reported to confer echinocandin resistance were found in Fks1 hot spot regions. In addition, three new amino acid alterations (D440A, S634R, and H1245R) were found outside Fks1 hot spot regions, and their contributions to echinocandin resistance need future investigation. Overall, our findings support the notion that L. prolificans is intrinsically resistant to azoles and echinocandins.

Eradication of Lomentospora prolificans Osteomyelitis of the Wrist with Combination Antifungal Therapy, Voriconazole Bone Cement, and Surgical Debridement

Lomentospora prolificans is an emerging pathogen that is difficult to treat due to its intrinsic resistance to currently available antifungal agents. Current evidence demonstrates synergy between Azoles and Terbinafine against L. prolificans infections, while adjunct use of antifungal agent-loaded bone cement has also shown favourable outcomes. We report a case of an immunosuppressed adult with rheumatoid arthritis who developed L. prolificans osteomyelitis in his right wrist following trauma and subsequent exposure to commercially available fertiliser. The infection was successfully eradicated via a combination of aggressive, staged surgical source control, antifungal therapy using voriconazole and Terbinafine, and insertion of voriconazole-loaded bone cement into the wrist and carpus. The utility of this approach supports the synergistic effects of voriconazole and Terbinafine and, more broadly, the clinical benefits of antifungal-loaded bone cement, as demonstrated in previous case reports and in vitro studies. As such, combination antifungal therapy and voriconazole-loaded bone cement should be considered the therapy of choice in cases of osteomyelitis where L. prolificans is proven to be the causative organism.

A fatal invasive Scedosporium apiospermum pulmonary infection in an adult patient with malignant lung adenocarcinoma

Background and Purpose:

Scedosporium apiospermum complex as a ubiquitous environmental mold is increasingly reported to cause an invasive fungal infection in immunosuppressive hosts. Herein, we present the case of an immunosuppressive 54 - year-old man who developed S. apiospermum complex lung infection and pulmonary adenocarcinoma.

Case report:

The patient had some complaints of dyspnea and cough during a neutropenic episode. The computed tomography (CT) scan of the patient revealed pleural effusion. After culturing the pleural fluid sample, the fungus was identified by microscopic examination and ITS sequencing. In addition, antifungal susceptibility testing was performed using the M38-A2 microdilution method. The minimum inhibitory concentrations of amphotericin B, voriconazole, posaconazole, and caspofungin were obtained as > 64, 0.06, 0.06, and 0.03 µg/mL, respectively. Voriconazole (administered in two doses of 6 mg/kg and a maximum of 250 mg) was preferred for treatment. The patient received antifungal treatment for 2 months; however, he was lost to follow-up.

Conclusion:

Scedosporium apiospermum complex should be considered a cause of systemic fungal infections in neutropenic patients. Furthermore, the determination of the in vitro antifungal susceptibilities of clinical strains may contribute to the development of therapeutic approaches.

Green Synthesis of Gold and Silver Nanoparticles Using Leaf Extract of Clerodendrum inerme; Characterization, Antimicrobial, and Antioxidant Activities

Due to their versatile applications, gold (Au) and silver (Ag) nanoparticles (NPs) have been synthesized by many approaches, including green processes using plant extracts for reducing metal ions. In this work, we propose to use plant extract with active biomedical components for NPs synthesis, aiming to obtain NPs inheriting the biomedical functions of the plants. By using leaves extract of Clerodendrum inerme (C. inerme) as both a reducing agent and a capping agent, we have synthesized gold (CI-Au) and silver (CI-Ag) NPs covered with biomedically active functional groups from C. inerme. The synthesized NPs were evaluated for different biological activities such as antibacterial and antimycotic against different pathogenic microbes (B. subtilis, S. aureus, Klebsiella, and E. coli) and (A. niger, T. harzianum, and A. flavus), respectively, using agar well diffusion assays. The antimicrobial propensity of NPs further assessed by reactive oxygen species (ROS) glutathione (GSH) and FTIR analysis. Biofilm inhibition activity was also carried out using colorimetric assays. The antioxidant and cytotoxic potential of CI-Au and CI-Ag NPs was determined using DPPH free radical scavenging and MTT assay, respectively. The CI-Au and CI-Ag NPs were demonstrated to have much better antioxidant in terms of %DPPH scavenging (75.85% ± 0.67% and 78.87% ± 0.19%), respectively. They exhibited excellent antibacterial, antimycotic, biofilm inhibition and cytotoxic performance against pathogenic microbes and MCF-7 cells compared to commercial Au and Ag NPs functionalized with dodecanethiol and PVP, respectively. The biocompatibility test further corroborated that CI-Ag and CI-Au NPs are more biocompatible at the concentration level of 1–50 µM. Hence, this work opens a new environmentally-friendly path for synthesizing nanomaterials inherited with enhanced and/or additional biomedical functionalities inherited from their herbal sources.

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.

Central Nervous System Infections Due to Aspergillus and Other Hyaline Molds

Central nervous system infections due to Aspergillus spp and other hyaline molds such as Fusarium and Scedosporium spp are rare but fatal conditions. Invasion of the central nervous system (CNS) tends to occur as a result of hematogenous dissemination among immunocompromised patients, and by local extension or direct inoculation secondary to trauma in immunocompetent hosts. Efforts should be directed to confirm the diagnosis by image-guided stereotactic brain biopsy when feasible. Non-culture methods could be useful to support the diagnosis, but they have not been validated to be performed in cerebral spinal fluid. Treatment of these infections is challenging given the variable susceptibility profile of these pathogens and the penetration of antifungal agents into the brain.

Broad spectrum triazoles for invasive mould infections in adults: Which drug and when?

Invasive mould infections are an increasing cause of morbidity and mortality globally, mainly due to increasing numbers of immunocompromised individuals at risk for fungal infections. The introduction of broad spectrum triazoles, which are much better tolerated compared to conventional amphotericin B formulations, has increased survival, particularly in invasive mould infection. However, early initiation of appropriate antifungal treatment remains a major predictor of outcome in invasive mould infection, but despite significant advances in diagnosis of these diseases, early diagnosis remains a challenge. As a result, prophylaxis with mould-active triazoles is widely used for those patients at highest risk for invasive mould infection, including patients with prolonged neutropenia after induction chemotherapy for acute myeloid leukemia and patients with graft-versus-host-disease. Posaconazole is the recommended drug of choice for antimould prophylaxis in these high-risk patients. Voriconazole has its primary role in treatment of invasive aspergillosis but not in prophylaxis. Recently, isavuconazole has been introduced as an excellent alternative to voriconazole for primary treatment of invasive aspergillosis in patients with hematological malignancies. Compared to voriconazole, isavuconazole and posaconazole have broader activity against moulds and are therefore also an option for treatment of mucormycosis in the presence of intolerance or contraindications against liposomal amphotericin B.

Developing collaborative works for faster progress on fungal respiratory infections in cystic fibrosis

Cystic fibrosis (CF) is the major genetic inherited disease in Caucasian populations. The respiratory tract of CF patients displays a sticky viscous mucus, which allows for the entrapment of airborne bacteria and fungal spores and provides a suitable environment for growth of microorganisms, including numerous yeast and filamentous fungal species. As a consequence, respiratory infections are the major cause of morbidity and mortality in this clinical context. Although bacteria remain the most common agents of these infections, fungal respiratory infections have emerged as an important cause of disease. Therefore, the International Society for Human and Animal Mycology (ISHAM) has launched a working group on Fungal respiratory infections in Cystic Fibrosis (Fri-CF) in October 2006, which was subsequently approved by the European Confederation of Medical Mycology (ECMM). Meetings of this working group, comprising both clinicians and mycologists involved in the follow-up of CF patients, as well as basic scientists interested in the fungal species involved, provided the opportunity to initiate collaborative works aimed to improve our knowledge on these infections to assist clinicians in patient management. The current review highlights the outcomes of some of these collaborative works in clinical surveillance, pathogenesis and treatment, giving special emphasis to standardization of culture procedures, improvement of species identification methods including the development of nonculture-based diagnostic methods, microbiome studies and identification of new biological markers, and the description of genotyping studies aiming to differentiate transient carriage and chronic colonization of the airways. The review also reports on the breakthrough in sequencing the genomes of the main Scedosporium species as basis for a better understanding of the pathogenic mechanisms of these fungi, and discusses treatment options of infections caused by multidrug resistant microorganisms, such as Scedosporium and Lomentospora species and members of the Rasamsonia argillacea species complex.

Scedosporium and Lomentospora: an updated overview of underrated opportunists

Species of Scedosporium and Lomentospora are considered as emerging opportunists, affecting immunosuppressed and otherwise debilitated patients, although classically they are known from causing trauma-associated infections in healthy individuals. Clinical manifestations range from local infection to pulmonary colonization and severe invasive disease, in which mortality rates may be over 80%. These unacceptably high rates are due to the clinical status of patients, diagnostic difficulties, and to intrinsic antifungal resistance of these fungi. In consequence, several consortia have been founded to increase research efforts on these orphan fungi. The current review presents recent findings and summarizes the most relevant points, including the Scedosporium/Lomentospora taxonomy, environmental distribution, epidemiology, pathology, virulence factors, immunology, diagnostic methods, and therapeutic strategies.

Lomentospora prolificans vertebral osteomyelitis with spinal epidural abscess in an immunocompetent woman: Case report and literature review

Lomentospora prolificans is a rare cause of vertebral osteomyelitis. We report a case of L. prolificans thoracic vertebral osteomyelitis with spinal epidural abscess in a patient without apparent immunodeficiency. Clinical manifestations and radiographic findings could not distinguish from other etiologic agents. Treatment is also challenging because L. prolificans is usually resistant to antifungal agents. The patient underwent surgical debridement and has been receiving a prolonged combination of antifungal therapy to prevent an infection relapse.

A cluster of scedosporiosis in lung transplant candidates and recipients: The Zurich experience and review of the literature

Scedosporium species are fungal pathogens increasingly recognized in cystic fibrosis (CF). They can cause multiresistant, life-threatening infections that are of particular concern in CF patients undergoing lung transplantation, as optimal treatment remains unclear. Here, we describe our Zurich experience of CF patients with Scedosporium infection. Disseminated infection occurred in one patient after transplantation and was successfully treated. We propose a step-by-step approach to treat candidates with colonization, and discuss our cases in the context of the current literature.

Rare fungal infectious agents: a lurking enemy

In the expanding population of immunocompromised patients and those treated in intensive care units, rare fungal infectious agents have emerged as important pathogens, causing invasive infections associated with high morbidity and mortality. These infections may present either as de novo or as breakthrough invasive infections in high-risk patients with hematologic malignancies receiving prophylactic or empirical antifungal therapy or in patients with central venous catheters. Diagnosis and treatment are challenging. Physicians should have a high index of suspicion because early diagnosis is of paramount importance. Conventional diagnostic methods such as cultures and histopathology are still essential, but rapid and more specific molecular techniques for both detection and identification of the infecting pathogens are being developed and hopefully will lead to early targeted treatment. The management of invasive fungal infections is multimodal. Reversal of risk factors, if feasible, should be attempted. Surgical debridement is recommended in localized mold infections. The efficacy of various antifungal drugs is not uniform. Amphotericin B is active against most yeasts, except Trichosporon, as well as against Mucorales, Fusarium, and some species of Paecilomyces and dimorphic fungi. The use of voriconazole is suggested for the treatment of trichosporonosis and scedosporiosis. Combination treatment, though recommended as salvage therapy in some infections, is controversial in most cases. Despite the use of available antifungals, mortality remains high. The optimization of molecular-based techniques, with expansion of reference libraries and the possibility for direct detection of resistance mechanisms, is awaited with great interest in the near future. Further research is necessary, however, in order to find the best ways to confront and destroy these lurking enemies.

Scedosporium apiospermum brain abscesses in a patient after near-drowning - a case report with 10-year follow-up and a review of the literature

Scedosporium apiospermum is known to be a fungal pathogen affecting immunocompromised as well as non-immunodeficient patients. Although this fungus is found rarely, an infection can lead to severe and even fatal disease. Here, we describe the case of a 41-year-old female who developed multiple Scedosporium apiospermum brain abscesses after near-drowning with aspiration of contaminated mud and water. She showed various neurological symptoms. The patient recovered after removal of abscesses in combination with long-term antifungal treatment.

Comparative Pathogenicity of Lomentospora prolificans (Scedosporium prolificans) Isolates from Mexican Patients

We identified 11 Lomentospora prolificans isolates recovered from Mexican patients using phenotypic and molecular characteristics. The identification of isolates was assessed by internal transcribed spacer (ITS rDNA) sequencing. In vitro susceptibility to amphotericin B, fluconazole, voriconazole, posaconazole, caspofungin, anidulafungin and micafungin was determined according to Clinical and Laboratory Standards Institute (CLSI) procedures. Three isolates (07-2239, 11-2242 and 04-2673) were used to induce systemic infection in immunocompetent ICR mice. Survival and tissue burden studies were used as markers of pathogenicity. All of the strains were resistant to every antifungal tested with MIC's for AmB (8->8 µg/ml), VRC (16->16 µg/ml), PSC (16->16 µg/ml), FLC (64->64 µg/ml) and echinocandins with MICs ≥8 µg/ml. One hundred, ninety and sixty percent of the infected mice with the strains 07-2239, 11-2242 and 04-2673 died during the study, respectively. Regarding tissue burden, the highest fungal load of the infected mice was detected in brain followed by spleen and kidney, regardless of the strain.

Scedosporium prolificans Septic Arthritis and Osteomyelitis of the Hip Joints in an Immunocompetent Patient: A Case Report and Literature Review

Scedosporium prolificans, also known as Scedosporium inflatum, is a fungus widespread in soil, sewage, and manure. This species is highly virulent and is an emerging opportunistic pathogen found in penetrating injuries in immunocompromised patients. Here we report on an immunocompetent patient with bilateral hip S. prolificans-associated osteomyelitis and septic arthritis caused by intentional penetrating trauma. The condition was refractory to initial antimicrobial suppression and surgical irrigation and debridement. Successful outcome was achieved after incorporating a bilateral two-stage total-hip-arthroplasty with Voriconazole-loaded cement and spacer.

Dematiaceous Molds

Dematiaceous fungi are the cause of phaeohyphomycosis, a term that encompasses many clinical syndromes, from local infections due to trauma to widely disseminated infection in immunocompromised patients. These fungi are unique owing to the presence of melanin in their cell walls, which imparts the characteristic dark color to their spores and hyphae. Melanin may also be a virulence factor. Local infection may be cured with excision alone, whereas systemic disease is often refractory to therapy. Azoles have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and treatment of these uncommon infections.

Surviving a recurrent Scedosporium prolificans endocarditis: Mention if consent was taken

Scedosporium prolificans have been reported to be resistant to all antifungals including the newer azoles and echinocandins. We report an unusual case of repeated S. prolificans infection of the heart valves in an immunocompetent patient.

[Strategies for antifungal treatment failure in intensive care units]

Recent epidemiologic studies reveal both an increasing incidence and an escalation in resistance of invasive fungal infections in intensive care units. Primary therapy fails in 70 % of cases, depending on the underlying pathogens and diseases. The purpose of this review is to raise awareness for the topic of antifungal therapy failure, describe the clinical conditions in which it occurs, and suggest a possible algorithm for handling the situation of suspected primary therapy failure.

Scedosporium apiospermum infections and the role of combination antifungal therapy and GM-CSF: A case report and review of the literature

Scedosporium apiospermum, a ubiquitous environmental mold, is increasingly reported as causing invasive fungal disease in immunocompromised hosts. It poses a therapeutic challenge due to its intrinsic resistance to traditional antifungals and ability to recur despite demonstrating susceptibility. We present an immunocompromised patient with a cutaneous S. apiospermum infection that disseminated despite treatment with voriconazole, the drug of choice. Adding echinocandins and GM-CSF provided partial recovery, indicating a potential synergistic role of dual-antifungal and immunotherapeutic agents.

Phaeohyphomycosis in Transplant Patients

Phaeohyphomycosis is caused by a large, heterogenous group of darkly pigmented fungi. The presence of melanin in their cell walls is characteristic, and is likely an important virulence factor. These infections are being increasingly seen in a variety of clinical syndromes in both immunocompromised and normal individuals. Transplant patients are especially at risk due their prolonged immunosuppression. There are no specific diagnostic tests for these fungi, though the Fontana-Masson stain is relatively specific in tissue. They are generally seen in a worldwide distribution, though a few species are only found in specific geographic regions. Management of these infections is not standardized due to lack of clinical trials, though recommendations are available based on clinical experience from case reports and series and animal models. Superficial infections may be treated without systemic therapy. Central nervous system infections are unique in that they often affect otherwise normal individuals, and are difficult to treat. Disseminated infections carry a high mortality despite aggressive therapy, usually with multiple antifungal drugs. Considerable work is needed to determine optimal diagnostic and treatment strategies for these infections.

Osteoarticular Infections Caused by Non-Aspergillus Filamentous Fungi in Adult and Pediatric Patients: A Systematic Review

Osteoarticular mycoses due to non-Aspergillus moulds are uncommon and challenging infections. A systematic literature review of non-Aspergillus osteoarticular mycoses was performed using PUBMED and EMBASE databases from 1970 to 2013. Among 145 patients were 111 adults (median age 48.5 [16-92 y]) and 34 pediatric patients (median age 7.5 [3-15 y]); 114 (79.7%) were male and 88 (61.9%) were immunocompromised. Osteomyelitis was due to direct inoculation in 54.5%. Trauma and puncture wounds were more frequent in children (73.5% vs 43.5%; P = 0.001). Prior surgery was more frequent in adults (27.7% vs 5.9%; P = 0.025). Vertebral (23.2%) and craniofacial osteomyelitis (13.1%) with neurological deficits predominated in adults. Lower limb osteomyelitis (47.7%) and knee arthritis (67.8%) were predominantly seen in children. Hyalohyphomycosis represented 64.8% of documented infections with Scedosporium apiospermum (33.1%) and Lomentospora prolificans (15.8%) as the most common causes. Combined antifungal therapy and surgery was used in 69% of cases with overall response in 85.8%. Median duration of therapy was 115 days (range 5-730). When voriconazole was used as single agent for treatment of hyalohyphomycosis and phaeohyphomycosis, an overall response rate was achieved in 94.1% of cases. Non-Aspergillus osteoarticular mycoses occur most frequently in children after injury and in adults after surgery. Accurate early diagnosis and long-course therapy (median 6 mo) with a combined medical-surgical approach may result in favorable outcome.

Fatal Cases of Bloodstream Infection by Fusarium solani and Review of Published Literature

Fusarium species are ubiquitously present in environment and are well known as human pathogens with high mortality rate in immunocompromised patients. We report here two cases where immunocompromised patients developed fatal bloodstream infections by this organism. Isolates were further identified by ITS1 region sequencing which confirmed them as Fusarium solani. Antifungal susceptibility testing was done following CLSI M38-A2 guidelines to amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, caspofungin, and micafungin. Both patients had a fatal outcome and expired of septic shock. Therefore, identification up to species level is of utmost importance as that helps in directing the management of the patient thereby leading to a favourable outcome.

Scedosporium apiosermum infection of the "Native" valve: Fungal endocarditis in an orthotopic heart transplant recipient

Scedosporium apiospermum is an increasingly appreciated pathogen in immunosuppressed patients. We present a case of S. apiospermum endocarditis in a 70-year-old male who had undergone orthotopic heart transplant. Echocardiogram demonstrated a 1.4 cm tricuspid valve vegetation. He underwent valve replacement, complicated by fatal massive post-operative haemorrhage. Valve cultures grew S. apiospermum. To our knowledge, our case is the first reported instance of endocarditis caused by S. apiospermum in a recipient of a cardiac transplant.