The challenge of managing fusariosis

Fusarium and Neocosmospora: fungal priority pathogens in laboratory diagnosis

Fusarium and Neocosmospora are two fungal genera recently recognized in the list of fungal priority pathogens. They cause a wide range of diseases that affect humans, animals, and plants. In clinical laboratories, there is increasing concern about diagnosis due to limitations in sample collection and morphological identification. Despite the advances in molecular diagnosis, due to the cost, some countries cannot implement these methodologies. However, recent changes in taxonomy and intrinsic resistance to antifungals reveal the necessity of accurate species-level identification. In this review, we discuss the current phenotypic and molecular tools available for diagnosis in clinical laboratory settings and their advantages and disadvantages.

[Fusarium meningoencephalitis in the late puerperium: A case report]

Background

Fusarium infection in the central nervous system is a rare pathology generally reported in patients with hematological malignancies.

Clincal case

A patient with Fusarium meningoencephalitis during the late postpartum period is presented. The patient's main symptom was holocranial headache with poor response to analgesics, adding dysarthria and blurred vision. Initially, it was classified as aseptic meningitis due to the absence of bacterial isolation, however, 8 weeks after the onset of the symptoms, Fusarium development was obtained in cerebrospinal fluid cultures. Targeted treatment with liposomal amphotericin and voriconazole was established, with partial improvement at first; however, at 16 weeks from the onset of the clinical picture, the patient presented sudden deterioration of alertness, an ischemic area was found in the occipital lobe by imaging study, which quickly led the patient to a fatal outcome.

Conclusion

Despite the fact that in recent years Fusarium spp infection has been detected more frequently in the population, the treatment is still not well established, making management of the Central Nervous System a challenge.

The Use of Host Biomarkers for the Management of Invasive Fungal Disease

Invasive fungal disease (IFD) causes severe morbidity and mortality, and the number of IFD cases is increasing. Exposure to opportunistic fungal pathogens is inevitable, but not all patients with underlying diseases increasing susceptibility to IFD, develop it. IFD diagnosis currently uses fungal biomarkers and clinical risk/presentation to stratify high-risk patients and classifies them into possible, probable, and proven IFD. However, the fungal species responsible for IFD are highly diverse and present numerous diagnostic challenges, which culminates in the empirical anti-fungal treatment of patients at risk of IFD. Recent studies have focussed on host-derived biomarkers that may mediate IFD risk and can be used to predict, and even identify IFD. The identification of novel host genetic variants, host gene expression changes, and host protein expression (cytokines and chemokines) associated with increased risk of IFD has enhanced our understanding of why only some patients at risk of IFD actually develop disease. Furthermore, these host biomarkers when incorporated into predictive models alongside conventional diagnostic techniques enhance predictive and diagnostic results. Once validated in larger studies, host biomarkers associated with IFD may optimize the clinical management of populations at risk of IFD. This review will summarise the latest developments in the identification of host biomarkers for IFD, their use in predictive modelling and their potential application/usefulness for informing clinical decisions.

Non-Mucormycetes Causes of Fungal Rhino Sinusitis With Periocular Swelling in COVID-19 With Delta Variant

Objective: To highlight fungi other than mucormycetes as causative agents of rhinosinusitis with periocular swelling in coronavirus (COVID-19) infection caused by Delta variant of SARS-CoV-2 virus and identify the presenting features, risk factors, intervention, and outcomes.

Methods and analysis: A retrospective interventional study of 96 patients with fungal rhinosinusitis and periocular swelling was done in patients with concurrent or recovered COVID-19 infection with the Delta variant (B.1.617.2) of SARS-CoV-2 virus in India. All patients with mucormycetes infection were excluded. Clinical presentation, medical history, blood reports, and imaging were analyzed. Management was by intravenous (IV) liposomal amphotericin B and functional endoscopic sinus surgery (FESS) with paranasal sinus debridement. Limited orbital debridement with or without transcutaneous retrobulbar liposomal amphotericin B (TRAMB) was done in patients with orbital involvement. Postoperative antifungal therapy was decided on the basis of the causative fungi.

Results: Four cases of Aspergillus and one each of Fusarium, Curvularia, and Penicillium-associated fungal rhinosinusitis with periocular swelling were seen. Signs of orbital involvement on MRI were present in all four of them. Two of these showed partial third-nerve palsy while one case with aspergillosis suffered cavernous sinus thrombosis. Proptosis was not witnessed in any case. History of diabetes and use of steroids was seen in all patients. All patients had mild to moderate COVID-19 with oxygen supplementation needed in one. No mortality, acute vision loss, or exenteration took place.

Conclusion: Aspergillus, Fusarium, Curvularia, and Penicillium were non-mucormycetes causes of fungal rhinosinusitis with periocular swelling in COVID-19 infection with the Delta variant (B.1.617.2) of SARS COV-2 virus. Few cases showed orbital and intracranial involvement.

COVID-19-associated fungal infections in Iran: A systematic review

Objectives

This systematic review aims to summarize the mycological and clinical features of COVID-19-associated fungal infections (CAFIs) in Iran.

Methods

PubMed, Web of Science, Scopus, Cochrane Library, SID, Magiran, IranDoc, and Google Scholar were searched for Persian and English articles published from January 1, 2020, to November 5, 2021, using a systematic search strategy. Studies on Iranian patients suffering from CAFIs were included in the review.

Results

Twenty-two studies comprising 169 patients were retrieved. Reported CAFIs included candidiasis (85, 50.30%), mucormycosis (35, 20.71%), aspergillosis (29, 17.16%), fusariosis (6, 3.55%), three cases caused by rare pathogens (Rhodotorula mucilaginosa, Diaporthe foeniculina, and Sarocladium kiliense) and 11 (6.51%) uncharacterized mold infections. The most common underlying diseases were diabetes (67/168, 39.88%), cardiovascular diseases (55/168, 32.74%), and hypertension (43/168, 25.59%). The use of antibiotics (111/124, 89.52%), corticosteroids (93/132, 70.44%), and mechanical ventilation (66, 51.16%) were the most common predisposing factors. Totally, 72 (50.35%) of 143 patients with CAFIs died (data were not available for 26 patients).

Conclusion

Fungal infections are evident to be a complication of COVID-19 in Iran; thus, clinicians should consider them as a differential diagnosis, especially in patients with comorbidities and previous antibiotic or corticosteroid use.

Multiple Fusarium brain abscesses in a young child

Isolated intracranial fungal infection is infrequent and mostly seen in high-risk, immunocompromised patients. Fusarium, a primary plant fungus, rarely contributes to such disease. Amongst the very few cases of Fusarium brain abscess that have been reported, the infection has occurred mostly in adults. We present a case of a 6-year-old boy with tuberculous meningitis diagnosed with multiple Fusarium brain abscess caused by Fusarium falciforme during his clinical course. An immunocompromised state secondary to tuberculous meningitis presumably led to this infection. After tapping the abscesses, the child was treated with a combination of amphotericin B, voriconazole and terbinafine. Despite an aggressive therapy, he remained in poor neurological state. This is the second report of an isolated Fusarium abscess in pediatric age and the first one in a young child and provides pertinent review of this unusual central nervous system fungal infection. Such unusual infectious spectrum should be borne in mind in patients with co-existent immunosuppression.

A rare Fusarium equiseti infection in a 53-year-old male with burn injury: A case report

Background and Purpose:

Burn injuries are prone to infection caused by bacteria, fungi, or other pathogens. Fungal wound infection usually has non-specific clinical symptoms. Nevertheless, in some cases, the fungal burden is so substantial that can easily be seen by the naked eyes, but this phenomenon has rarely been reported with Fusarium.

Case report:

A 53-year-old patient with severe burn injury was admitted to the intensive care unit of the National Hospital of Burn, Ha Noi, Vietnam. His wound was dressed with a traditional herbal product before the hospital admission. On the 5th day after the admission, some white patches suspected of fungal colonies appeared on burn lesions where the herbal medicine was placed. Histological examination (Periodic acid-Schiff) and culture of biopsy samples taken from those lesions revealed fungus that was identified as Fusarium equiseti after analysis of the internal transcribed spacer and D1/D2 region of the large subunit of the 28S rDNA. The isolated strain showed susceptibility to voriconazole but resistance to fluconazole, itraconazole, caspofungin, and amphotericin B in vitro. The patient received aggressive treatment, including IV voriconazole (400 mg daily from day five); however, he could not recover.

Conclusion:

Fusarium should be suspected in burn patients with white patches on lesions. Antifungal susceptibility testing is important since multidrug resistance is common among Fusarium strains.

Fungal burn wound infection caused by Fusarium dimerum: A case series on a rare etiology

Introduction

Fusarium dimerum is a filamentous mold associated with poor outcomes in immunocompromised hosts and burn victims. It can be acquired via inhalation or through skin dehiscence.

Methods

Our work presents a Case series of 8 patients from ages 3–57 years who were admitted with multiple burn wounds over the past 6 months. After initial stabilization measures, they all underwent debridement for the lesions after negative initial fungal cultures. The 44-year-old male was the first patient to develop punched-out eruptions on burn areas 7 days after admission; all the other patients experienced similar lesions during the next 6 days. Tissue cultures of the lesions exhibited Fusarium dimerum growth. The patients were managed accordingly with amphotericin B or voriconazoles. All the patients recovered except the 11-year-old boy, who expired on day 9 due to ARDS and sepsis complications.

Outcomes

Infection with Fusarium dimerum carries a high risk of dissemination in burn infections. Hence, appropriate screening should be carried out via histologic and mycologic diagnostics early in the disease course.

Conclusion

Considering the sparse literature that is available regarding Fusarium infection in burn victims, this study aims to improve the knowledge surrounding different facets of this disease including its epidemiology, diagnosis, management, and the need to maintain high suspicion of this fungal disease in burn patients.

•

Fusarium dimerum is a filamentous mold associated with poor outcomes in immunocompromised hosts and burn victims. It can be acquired via inhalation or through skin dehiscence.

•

Our work presents a Case series of 8 patients from ages 3–57 years who were admitted with multiple burn wounds over the past 6 months. After initial stabilization measures, they all underwent debridement for the lesions after negative initial fungal cultures.

•

Infection with Fusarium dimerum carries a high risk of dissemination in burn infections. Hence, appropriate screening should be carried out via histologic and mycologic diagnostics early in the disease course.

Disinfectants in a Hemodialysis Setting: Antifungal Activity Against Aspergillus and Fusarium Planktonic and Biofilm Cells and the Effect of Commercial Peracetic Acid Residual in Mice

Aspergillus and Fusarium cause a broad spectrum of infections in humans, mainly in immunocompromised patients. Among these, patients undergoing hemodialysis are highly susceptible to infections, requiring a constant and adequate environmental disinfection program. Nevertheless, monitoring the residual disinfectants can contribute to the morbidity and mortality reduction in these patients. Here, we evaluated the susceptibility of Aspergillus spp. (n=19) and Fusarium spp. (n=13) environmental isolates against disinfectants (acetic acid, citric acid, peracetic acid, sodium hypochlorite, and sodium metabisulphite) at different concentrations and time exposures. Also, we investigated the in vivo toxicity of the peracetic acid residual concentration in mice. Fusarium isolates were identified by F. equiseti, F. oxysporum and F. solani while Aspergillus presented clinically relevant species (A. fumigatus, A. niger and A. terreus) and environmental ones. Against planktonic cells, only two disinfectants (acetic acid and sodium hypochlorite) showed a fungicidal effect on Fusarium spp., while only one (sodium hypochlorite) was effective against Aspergillus spp. Both fungi formed robust in vitro biofilms with large amounts of the extracellular matrix, as evidenced by electron micrographs. Exposure of fungal biofilms to disinfectants showed sensitivity to three (acetic, citric, and peracetic acids), although the concentrations and times of exposure varied according to the fungal genus. Mice exposure to the residual dose of peracetic acid during 60 weeks showed anatomopathological, hematological, and biochemical changes. The implementation of news control measures and those that already exist can help reduce infections, the second cause of death and morbidity in these patients, besides providing safety and well-being to them, a priority of any quality health program.

Prevalence, species distribution, and risk factors of fungal colonization and infection in patients at a burn intensive care unit in Vietnam

Background and Purpose :

Burn patients are at a higher risk of infections caused by different organisms. This study aimed to address the prevalence, causative species, and factors related to fungal colonization or infection in patients with acute severe injuries admitted to the intensive care unit (ICU) of a burn hospital in northern Vietnam.

Materials and Methods:

This prospective study was conducted on 400 patients in a burn ICU between 2017 and 2019. Clinical samples were weekly collected and screened for fungi, and relevant clinical information was obtained from medical records.

Results:

According to the results, 90% of the patients were colonized with fungi. Out of this group, 12.75% of the cases had invasive fungal infection (IFI). Eleven yeasts and six mold species were isolated from the patients, with the most common species being Candida tropicalis (45.56%) and C. albicans (41.94%). Among the eleven species causing fungal wound infection (FWI), the most common agents were Candida (66.7% of FWI patients) and Aspergillus (38.5%) species. Three Candida species isolated from blood were C. tropicalis (66.7%), C. albicans (20.0%), and C. parapsilosis (14.3%). No factors were found to expose the patients to a higher risk of fungal colonization. However, hyperglycemia, prolonged ICU stay, and heavy Candida species colonization were found to be independently predictive of IFI.

Conclusion:

Burn patients are at the risk of fungal infection with Candida species (especially C. tropicalis) and Aspergillus as the most frequently responsible agents. Continuous surveillance of fungi and appropriate management of pathophysiological consequences are essential to prevent fungal infection in burn patients.

In vitro activity of olorofim against clinical isolates of the Fusarium oxysporum and Fusarium solani species complexes

BACKGROUND

Invasive fusariosis is associated with marked morbidity and mortality in immunocompromised hosts, and clinical outcomes are poor with conventional therapy. Olorofim (F901318) is an investigational antifungal in the orotomide class that selectively targets fungal dihydroorotate dehydrogenase (DHODH) causing inhibition of pyrimidine biosynthesis.

OBJECTIVE

We evaluated the in vitro activity of olorofim against 61 clinical isolates of the Fusarium oxysporum and F solani species complexes (FOSC and FSSC, respectively), the most prevalent causes of invasive fusariosis.

METHODS

Clinical isolates of FOSC (n = 45) and FSSC (n = 16) were identified using DNA sequence analysis of the translation elongation factor 1-alpha (TEF1α) and RNA polymerase II second largest subunit (RPB2). Antifungal susceptibility testing was performed by CLSI M38 broth microdilution for olorofim, amphotericin B, isavuconazole, posaconazole, voriconazole and micafungin.

RESULTS

Olorofim demonstrated good in vitro activity against both FOSC and FSSC. Against the 45 FOSC isolates, olorofim MICs ranged between 0.03-0.5 mg/L and 0.06->4 mg/L at the 50% and 100% inhibition endpoints, respectively. Against FSSC isolates, olorofim MIC ranged between 0.25-1 mg/L and 1->4 mg/L at 50% and 100% inhibition, respectively. While amphotericin B also demonstrated similar in vitro activity (MIC ranges 1-4 and 0.25-4 mg/L against FOSC and FSSC, respectively), neither the triazoles nor micafungin demonstrated consistent in vitro activity against Fusarium isolates at clinically relevant concentrations.

CONCLUSIONS

The investigational agent olorofim demonstrated good in vitro activity against FOSC and FSSC clinical isolates. Further studies are warranted to determine how well this in vitro activity translates into in vivo efficacy.

Activity of MSI-78, h-Lf1-11 and cecropin B antimicrobial peptides alone and in combination with voriconazole and amphotericin B against clinical isolates of Fusarium solani

Fusarium infections have been associated with high mortality rates due to the lack of definition of an ideal treatment strategy. Antimicrobial peptides (AMPs) have potential antifungal activity. Therefore, investigating the in vitro activity of these molecules alone and in association with conventional antifungals against clinical isolates of Fusarium was the aim of this study. Fusarium solani (n=10) strains were tested against the AMPs, MSI-78, h-Lf1-11 and cecropin B in accordance with CLSI protocol. Further, a checkerboard assay for its combination with amphotericin B or voriconazole, was carried out. MSI-78, h-Lf1-11 and cecropin B exhibited antifungal activity against F. solani strains tested with MICs ranging from 20 to 320mg/L. Satisfactory percentage of synergism was demonstrated for all evaluated combinations, ranging from 70 to 100%. The use of AMPs combined with amphotericin B and voriconazole antifungals has great synergistic potential and deserve to be evaluated in murine models of fusariosis.

Fusarium-Induced Cellulitis in an Immunocompetent Patient With Sickle Cell Disease: A Case Report

Fungal infections due to Fusarium species are mostly present in immunocompromised and patients with poorly controlled diabetes mellitus. We report a case of lower extremity skin infection caused by Fusarium species in a 61-year-old woman diagnosed with sickle cell disease. Single skin ulceration caused by Fusarium species can result from fungal inoculation into damaged tissue, so any condition that damages the skin can be considered as a risk factor for inoculation. Long-standing sickle cell disease may develop vaso-occlusion in the skin that can produce lower extremity ulcers and myofascial syndromes. The mechanism is not completely characterized, but compromised blood flow, endothelial dysfunction, thrombosis, inflammation, and delayed healing are thought to contribute to locally compromised tissue that may eventually lead to opportunistic infection such as in our case. Other factors contribute to the pathophysiology of lower extremity ulcers such as diabetes mellitus, with the resulting peripheral vascular ischemia causing poor circulation to the lower extremity, and peripheral neuropathy, which can make patients with diabetes unaware of minor trauma leading to the development of skin infections.

Fusarium volatile, a new potential pathogen from a human respiratory sample

We describe the isolation and characterization of Fusarium volatile from a bronchoalveolar lavage (BAL) sample of a female patient living in French Guiana with underlying pulmonary infections. Phylogenetic analysis of fragments of the calmodulin (cmdA), translation elongation factor (tef1), RNA polymerase second largest subunit (rpb2), and β-tubulin (tub) loci revealed that strain CBS 143874 was closely related to isolate NRRL 25615, a known but undescribed phylogenetic species belonging to the African clade of the Fusarium fujikuroi species complex. The fungus differed phylogenetically and morphologically from related known species, and is therefore described as the new taxon Fusarium volatile. Antifungal susceptibility testing suggested that the new species is resistant to echinocandins, fluconazole, itraconazole with lower MICs against amphotericin B, voriconazole and posaconazole.

A Rare Case of Fungal Burn Wound Infection Caused by Fusarium solani in Vietnam

A patient with extensive burn injuries was admitted to the National Hospital of Burns in Hanoi, Vietnam, and diagnosed with fungal wound infection by histological examination of skin biopsy samples. Fusarium solani was isolated and identified by analysis of its morphological features and the sequence of the internal transcribed spacer region. The isolation showed in vitro resistant to fluconazole, voriconazole, itraconazole, amphotericin B, and caspofungin. Invasive fusariosis is difficult to treat due to its angioinvasive property and its lacking amenability to treatment with antifungal drugs. This infection is rare and has not been reported so far in Vietnam.

Detection of the 'Big Five' mold killers of humans: Aspergillus, Fusarium, Lomentospora, Scedosporium and Mucormycetes

Fungi are an important but frequently overlooked cause of morbidity and mortality in humans. Life-threatening fungal infections mainly occur in immunocompromised patients, and are typically caused by environmental opportunists that take advantage of a weakened immune system. The filamentous fungus Aspergillus fumigatus is the most important and well-documented mold pathogen of humans, causing a number of complex respiratory diseases, including invasive pulmonary aspergillosis, an often fatal disease in patients with acute leukemia or in immunosuppressed bone marrow or solid organ transplant recipients. However, non-Aspergillus molds are increasingly reported as agents of disseminated diseases, with Fusarium, Scedosporium, Lomentospora and mucormycete species now firmly established as pathogens of immunosuppressed and immunocompetent individuals. Despite well-documented risk factors for invasive fungal diseases, and increased awareness of the risk factors for life-threatening infections, the number of deaths attributable to molds is likely to be severely underestimated driven, to a large extent, by the lack of readily accessible, cheap, and accurate tests that allow detection and differentiation of infecting species. Early diagnosis is critical to patient survival but, unlike Aspergillus diseases, where a number of CE-marked or FDA-approved biomarker tests are now available for clinical diagnosis, similar tests for fusariosis, scedosporiosis and mucormycosis remain experimental, with detection reliant on insensitive and slow culture of pathogens from invasive bronchoalveolar lavage fluid, tissue biopsy, or from blood. This review examines the ecology, epidemiology, and contemporary methods of detection of these mold pathogens, and the obstacles to diagnostic test development and translation of novel biomarkers to the clinical setting.

β-1,6-linked Galactofuranose- rich peptidogalactomannan of Fusarium oxysporum is important in the activation of macrophage mechanisms and as a potential diagnostic antigen

A peptidogalactomannan (PGM) from Fusarium oxysporum was structurally characterized by a combination of chemical and spectroscopic methods, including one and two-dimensional nuclear magnetic resonance (1D and 2D NMR). The galactomannan component consists of a main chain containing (1→6)-linked β-D-galactofuranose residues with side chains containing (1→2)-linked α-D-Glcp, (1→2)-linked -β-D-Manp (1→2) and β-D-Manp terminal nonreducing end units and differs from that of Aspergillus fumigatus and Cladosporium resinae that present a main chain containing (1→6)-linked α-D-Manp residues presenting β-D-Galf as side chains of 3-4 units that are (1→5)-interlinked. The importance of the carbohydrate moiety of the F. oxysporum PGM was demonstrated. Periodate oxidation abolished much of the PGM antigenic activity. A strong decrease in reactivity was also observed with de-O-glycosylated PGM. In addition, de-O-glycosylated PGM was not able to inhibit F. oxysporum phagocytosis, suggesting that macrophages recognize and internalize F. oxysporum via PGM. F. oxysporum PGM triggered TNF-α release by macrophages. Chemical removal of O-linked oligosaccharides from PGM led to a significant increase of TNF-α cytokine levels, suggesting that their removal could exposure another PGM motifs able to induce a higher secretion of TNF-α levels. Interestingly, F. oxysporum conidia, intact and de-O-linked PGM were not able to induce IL-10 cytokine release. The difference in patient serum reativity using a PGM from F. oxysporum characterized in the present study as compared with a PGM from C. resinae, that presents the same epitopes recognized by serum from patients with aspergillosis, could be considered a potential diagnostic antigen and should be tested with more sera.

Successful treatment of disseminated fusariosis in a patient with acute lymphoblastic leukemia: A case report and literature review

RATIONALE

Fusarium is the second most common cause of fungi infections in the immunocompromised patients with the mortality rate over 80%. Early identification and appropriate selection of antifungal drugs is the key to successful treatment.

PATIENT CONCERNS

A 31-year-old female was diagnosed with acute lymphocytic leukemia (pro-B ALL). She developed a high fever and presented with typical painful purple nodules with central necrosis formed on the upper and lower limbs during the induction chemotherapy.

DIAGNOSIS

Combining clinical manifestations with results of blood culture testing and sequencing methods, it was consistent with the diagnosis of disseminated fusariosis.

INTERVENTIONS

The patient was treated with the combination of tigecycline and antifungal agents (Liposomal Amphotericin B and Voriconazole), OUTCOMES:: The skin lesions generally healed with some scar left after treating with antifungal agents for 6 weeks. The final date of follow-up was 1.5 years later, and the patient was alive with no diseases.

LESSONS

This case highlights the importance of the typical cutaneous lesions for early diagnosis and proper treatment to decrease the mortality rate of this severe infection. This patient was successfully treated with the combination of tigecycline and antifungal agents, which may be the first clinical confirmation of tigecycline that improved the effectiveness of antifungal agents against fusariosis, but it requires more studies to verify. We reviewed 62 cases from literature and analyzed using logistic regression and recognized the high-risk factor for fusariosis mortality in patients with acute leukemia was non-remission of underlying disease.

Potent Activities of Luliconazole, Lanoconazole, and Eight Comparators against Molecularly Characterized Fusarium Species

A collection of clinical (n = 47) and environmental (n = 79) Fusarium isolates were tested against 10 antifungal drugs, including 2 novel imidazoles. Luliconazole and lanoconazole demonstrated very low geometric mean MIC values of 0.005 and 0.013 μg/ml, respectively, compared with 0.51 μg/ml for micafungin, 0.85 μg/ml for efinaconazole, 1.12 μg/ml for natamycin, 1.18 μg/ml for anidulafungin, 1.31 μg/ml for voriconazole, 1.35 μg/ml for caspofungin, 1.9 μg/ml for amphotericin B, and 4.08 μg/ml for itraconazole. Results show that these drugs are potential candidates for (topical) treatment of skin and nail infections due to Fusarium species.

Native valve endocarditis, fusarium and end-stage renal disease

We would like to report a case of invasive Fusariosis involving the native mitral valve and complicated by septic thromboembolism. The patient was a known case of end-stage renal disease on maintenance haemodialysis and did not have any of the known risk factors for invasive Fusariosis like neutropaenia, severe T cell immunodeficiency, postsolid organ transplant recipients, posthaematopoietic stem cell transplant recipients and patients who received cytotoxic and/or high-dose corticosteroid therapy.

Fungal Pneumonia in Patients with Hematologic Malignancies and Hematopoietic Cell Transplantation

Invasive fungal infections, which occur primarily as a consequence of prolonged neutropenia and immunosuppression, are a life-threatening complication seen among patients with hematologic malignancies. The routine use of triazole antifungal prophylaxis, enhanced diagnostics, and newer antifungal agents have led to improvements in the care of fungal pneumonias, but invasive fungal infections remain a major cause of morbidity and mortality. This article covers risk factors for major fungal infections, diagnostic approaches, and treatment options for specific fungal pathogens, including Aspergillus and Mucorales species, and discusses current approved strategies for prevention of common and uncommon fungal pneumonias.

Current antifungal treatment of fusariosis

Fungi of the genus Fusarium are well known as major plant pathogens and soil inhabitants, but also cause a broad spectrum of human infections. Fusariosis is the second most common mould infection after aspergillosis, and keratitis is the most encountered implantation infection in immunocompetent individuals. Natamycin is active against Fusarium species both in vitro and in vivo, and is used along with voriconazole as the mainstay of treatment for Fusarium keratitis. Onychomycosis is treated with terbinafine, voriconazole and sometimes itraconazole. Cure is possible despite high in vitro minimum inhibitory concentrations (MICs). Recently, disseminated infections have increased dramatically, mainly affecting severely immunocompromised patients. The remarkable intrinsic resistance of Fusarium species to most antifungal agents results in high mortality rates in this patient population. Recovery of neutropenia is essential for patient survival and treatment should include voriconazole or amphotericin B as first-line and posaconazole as salvage therapy.

Antifungal Susceptibility Testing of Fusarium: A Practical Approach

In vitro susceptibility testing of Fusarium is becoming increasingly important because of frequency and diversity of infections and because resistance profiles are species-specific. Reference methods for antifungal susceptibility testing (AFST) are those of Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility (EUCAST), but breakpoints (BPs) have not yet been established. One of the problems is that phylogenetic distances between Fusarium species are much smaller than between species of, e.g., Candida. Epidemiological cutoff values (ECVs) for some Fusarium species have been determined in order to differentiate wild-type from non-wild-type isolates. In clinical routine, commercially available assays such as Etest, Sensititre or others provide essential agreement with reference methods. Our objective is to summarize antifungal susceptibility testing of Fusarium genus in the clinical laboratory: how to do it, when to do it, and how to interpret it.

Emerging infectious diseases with cutaneous manifestations: Fungal, helminthic, protozoan and ectoparasitic infections

Given increased international travel, immigration, changing climate conditions, and the increased incidence of iatrogenic immunosuppression, fungal, protozoan, helminthic, and ectoparasitic infections that were once uncommon are being seeing more frequently in the Western hemisphere. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. In addition, delays in the diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. We review the epidemiology, cutaneous manifestations, diagnostic modalities, and treatment options for emerging fungal, protozoan, helminthic, and ectoparasitic infections. It should be noted, however, that throughout this review we cite statistics documenting their increased incidence to back-up these infections as emerging, and although some of the diagnoses are clinical, others rely on newer laboratory tests, and the possibility exists that the increased incidence could be caused by better detection methods.

Rare case of disseminated fusariosis in a young patient with graft vs. host disease following an allogeneic transplant

Fusarium infection is a severe fungal infection caused by fungi of the genus Fusarium. It most commonly occurs in immunocompromised patients with malignant hematological comorbidities or secondary to hematopoietic stem cell transplant. The classical route of contamination is through inhalation but infection may also occur through contiguity with a skin lesion. This report describes the case of a 24-year-old woman who developed graft-vs.-host disease (GVHD) at 220 days after receiving an allogeneic stem cell transplant from a sibling donor for Hodgkin disease. On day 330 after transplant the patient presented with fever and several painful subcutaneous, tender, red nodules with ulcerative and necrotic features on the pelvic region and right leg, extensive glass infiltrative lesions in the lungs and pansinusitis; however, the patient did not have onychomycosis. Following skin biopsy, culture of cutaneous lesions, computed tomography (CT) scanning of the lungs and CT scanning and magnetic resonance imaging of facial sinuses the patient was diagnosed with disseminated Fusarium species infection. Despite intensive treatment with voriconazole, the patient succumbed with respiratory insufficiency on day 400 after transplant. This case is noteworthy because the patient did not have any additional risk associated with the allogeneic transplant; there was no transplant mismatch, no severe neutropenia and no prior clinical signs of onychomycosis. The association of skin lesions with GVHD lesions increased the initial immunosuppression and delayed diagnosis.

Distinct galactofuranose antigens in the cell wall and culture supernatants as a means to differentiate Fusarium from Aspergillus species

Detection of carbohydrate antigens is an important means for diagnosis of invasive fungal infections. For diagnosis of systemic Aspergillus infections, galactomannan is commonly used, the core antigenic structure of which consists of chains of several galactofuranose moieties. In this study, we provide evidence that Fusarium produces at least two distinct galactofuranose antigens: Smaller amounts of galactomannan and larger quantities of a novel antigen recognized by the monoclonal antibody AB135-8. In A. fumigatus, only minor amounts of the AB135-8 antigen are found in supernatants and in the apical regions of hyphae. A galactofuranose-deficient A. fumigatus mutant lacks the AB135-8 antigen, which strongly suggests that galactofuranose is an essential constituent of this antigen. Using a combination of AB135-8 and a galactomannan-specific antibody, we were able to unambiguously differentiate A. fumigatus and Fusarium hyphae in immunohistology. Moreover, since Fusarium releases the AB135-8 antigen, it appears to be a promising target antigen for a serological detection of Fusarium infections.

Fusariosis in a Patient with Acute Myeloid Leukemia: A Case Report and Review of the Literature

Fusarium spp. causes infections mostly in patients with prolonged neutropenia. We describe the case of a disseminated Fusarium solani infection in a patient with acute myeloid leukemia which never reached complete remission during its clinical course. The patient had profound neutropenia and developed skin nodules and pneumonia in spite of posaconazole prophylaxis. F. solani was isolated from blood and skin biopsy, being identified from its morphology and by molecular methods. By broth dilution method, the strain was resistant to azoles, including voriconazole and posaconazole, and to echinocandins. MIC to amphotericin B was 4 mg/L. The patient initially seemed to benefit from therapy with voriconazole and amphotericin B, but, neutropenia perduring, his clinical condition deteriorated with fatal outcome. All efforts should be made to determine the correct diagnosis as soon as possible in a neutropenic patient and to treat this infection in a timely way, assuming pathogen susceptibility while tests of antimicrobial susceptibility are pending. A review of the most recent literature on invasive fungal infections is reported.

Detection of human pathogenic Fusarium species in hospital and communal sink biofilms by using a highly specific monoclonal antibody

The fungus Fusarium is well known as a plant pathogen, but has recently emerged as an opportunistic pathogen of humans. Habitats providing direct human exposure to infectious propagules are largely unknown, but there is growing evidence that plumbing systems are sources of human pathogenic strains in the Fusarium solani species complex (FSSC) and Fusarium oxysporum species complex (FOSC), the most common groups infecting humans. Here, a newly developed Fusarium-specific monoclonal antibody (mAb ED7) was used to track FSSC and FOSC strains in sink drain biofilms by detecting its target antigen, an extracellular 200 kDa carbohydrate, in saline swabs. The antigen was detectable in 52% of swab samples collected from sinks across a University campus and a tertiary care hospital. The mAb was 100% accurate in detecting FSSC, FOSC, and F. dimerum species complex (FDSC) strains that were present, as mixed fungal communities, in 83% of sink drain biofilms. Specificity of the ELISA was confirmed by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2 rRNA-encoding regions of culturable yeasts and molds that were recovered using mycological culture, while translation elongation factor (TEF)-1α analysis of Fusarium isolates included FSSC 1-a, FOSC 33, and FDSC ET-gr, the most common clinical pathotypes in each group.

Disseminated fusariosis by Fusarium proliferatum in a patient with aplastic anaemia receiving primary posaconazole prophylaxis - case report and review of the literature

Disseminated fusariosis is a life-threatening, invasive, opportunistic infection in immunocompromised patients, especially those with haematological malignancies. The prognosis is poor because these fungi are resistant to many of the available antifungal agents. We present a case of disseminated fusariosis caused by Fusarium proliferatum in a patient with severe aplastic anaemia complicated by a secondary infection of Aspergillus flavus, with a fatal outcome. We also review the documented Fusarium infections in immunocompromised hosts.

Invasive Fusariosis: A Single Pediatric Center 15-Year Experience

Invasive fungal infection (IFI) is an important cause of mortality in immunocompromised children, particularly after hematopoietic stem cell transplantation. We describe 5 cases of Fusarium IFI in immunocompromised children seen at our institution over a 15-year period. A summary of all published pediatric cases of invasive Fusarium infection is presented. A focus on antifungal management challenges in these patients will be discussed.

Adaptation of Fusarium oxysporum and Fusarium dimerum to the specific aquatic environment provided by the water systems of hospitals

Members of the Fusarium group were recently detected in water distribution systems of several hospitals in the world. An epidemiological investigation was conducted over 2 years in hospital buildings in Dijon and Nancy (France) and in non-hospital buildings in Dijon. The fungi were detected only within the water distribution systems of the hospital buildings and also, but at very low concentrations, in the urban water network of Nancy. All fungi were identified as Fusarium oxysporum species complex (FOSC) and Fusarium dimerum species complex (FDSC) by sequencing part of the translation elongation factor 1-alpha (TEF-1α) gene. Very low diversity was found in each complex, suggesting the existence of a clonal population for each. Density and heterogeneous distributions according to buildings and variability over time were explained by episodic detachments of parts of the colony from biofilms in the pipes. Isolates of these waterborne populations as well as soilborne isolates were tested for their ability to grow in liquid medium in the presence of increasing concentrations of sodium hypochlorite, copper sulfate, anti-corrosion pipe coating, at various temperatures (4°-42 °C) and on agar medium with amphotericin B and voriconazole. The waterborne isolates tolerated higher sodium hypochlorite and copper sulfate concentrations and temperatures than did soilborne isolates but did not show any specific resistance to fungicides. In addition, unlike waterborne isolates, soilborne isolates did not survive in water even supplemented with glucose, while the former developed in the soil as well as soilborne isolates. We concluded the existence of homogeneous populations of FOSC and FDSC common to all contaminated hospital sites. These populations are present at very low densities in natural waters, making them difficult to detect, but they are adapted to the specific conditions offered by the complex water systems of public hospitals in Dijon and Nancy and probably other localities in the world.

Role of granulocyte transfusions in invasive fusariosis: systematic review and single-center experience

BACKGROUND

Invasive Fusarium infection is relatively refractory to available antifungal agents. Invasive fusariosis (IF) occurs almost exclusively in the setting of profound neutropenia and/or systemic corticosteroid use. Treatment guidelines for IF are not well established, including the role of granulocyte transfusions (GTs) to counter neutropenia.

STUDY DESIGN AND METHODS

We conducted a systematic review, identifying IF cases where GTs were used as adjunctive therapy to antifungal agents and also report a single-center case series detailing our experience (1996-2012) of all IF cases treated with antifungal agents and GTs. In the systematic review cases, GTs were predominantly collected from nonstimulated donors whereas, in the case series, they were universally derived from dexamethasone- and granulocyte-colony-stimulating factor-stimulated donors.

RESULTS

Twenty-three patients met inclusion criteria for the systematic review and 11 for the case series. Response rates after GTs were 30 and 91% in the review and case series, respectively. Survival to hospital discharge remained low at 30 and 45%, respectively. Ten patients in the systematic review and three in the case series failed to achieve hematopoietic recovery and none of these survived. In the case series, donor-stimulated GTs generated mean "same-day" neutrophil increments of 3.35 × 10(9)  ± 1.24 × 10(9) /L and mean overall posttransfusion neutrophil increments of 2.46 × 10(9)  ± 0.85 × 10(9) /L. Progressive decrements in neutrophil response to GTs in two cases were attributed to GT-related HLA alloimmunization.

CONCLUSION

In patients with IF, donor-stimulated GTs may contribute to high response rates by effectively bridging periods of neutropenia or marrow suppression. However, their utility in the absence of neutrophil recovery remains questionable.

Disseminated fusariosis and hematologic malignancies, a still devastating association. Report of three new cases

BACKGROUND

Fungi of the genus Fusarium are primarily plant pathogens and saprobes that produce disseminated infections in immunologically deficient humans. After aspergillosis, disseminated fusariosis is the second most common cause of invasive infection by filamentous fungi in patients with hematologic malignancies or those undergoing transplants of hematopoietic progenitors.

AIMS

Disseminated fusariosis (DF) is considered an extremely rare infection and has reached a stable incidence rate, but its high mortality rate and the lack of an optimal management protocol have raised increasing interest in this mycosis.

METHODS

We present three cases of DF produced by Fusarium oxysporum species complex, Fusarium solani species complex and the highly unusual Fusarium dimerum in patients with advanced hematological malignancies diagnosed in our hospital between 2007 and 2011. The species level identification of the Fusarium isolates was established by sequencing their TEF1 gene.

RESULTS

The isolates showed low susceptibility to most of the antifungal agents analyzed, except that observed for F. dimerum to amphotericin B (AmB) and terbinafine, and F. oxysporum species complex to AmB. Interestingly, the strain of F. solani species complex exhibited high MIC values for AmB and voriconazole, notwithstanding these drugs were used for treatment with good results. Other relevant aspects to be considered in the treatment of DF are surgically cleaning foci of infection, withdrawing presumably contaminated catheters and recovery from neutropenia.

CONCLUSIONS

The prevention of infection in colonized patients, the maintenance of a high level of diagnostic suspicion for early diagnosis, and the combined, vigorous and prolonged use of L-AmB and voriconazole are essential to decrease the mortality rate of this devastating infection.

New 1,4-anthracenedione derivatives with fused heterocyclic rings: synthesis and biological evaluation

New 1,4-anthracenediones bearing fused-heterocycle rings were synthesized and evaluated as cytotoxics, antifungals and antivirals. Some of them showed GI₅₀ at the μM level.

Specific antifungal susceptibility profiles of opportunists in the Fusarium fujikuroi complex

OBJECTIVES

The aim of the present study was to evaluate and assess the in vitro activity of eight drugs, including the new azole isavuconazole, against 81 strains representing 13 species of the Fusarium fujikuroi species complex.

METHODS

A total of 81 Fusarium spp. isolates, within the F. fujikuroi species complex, were identified by molecular methods and tested according to CLSI M38-A2. Eight antifungal compounds, including the new azole isavuconazole, were tested. Isolates were selected to represent the widest variety of geographical regions and to include clinical as well as environmental strains.

RESULTS

Susceptibility profiles differed between and within species, with Fusarium verticillioides showing the lowest MICs and Fusarium nygamai the highest MICs. Amphotericin B was the most active drug, followed by voriconazole, posaconazole, isavuconazole and natamycin. The remaining antifungals (fluconazole, itraconazole and micafungin) showed poor activity with MIC/minimum effective concentration values of ≥ 32, ≥ 16 and >8 mg/L, respectively.

CONCLUSIONS

Resistance patterns in the F. fujikuroi species complex are species specific and therefore identification down to species level is important for the choice of antifungal treatment.

Fungaemia caused by Fusarium proliferatum in a patient without definite immunodeficiency

Recent literature has shown the growing importance of opportunistic fungal infections due to Fusarium spp. However, disseminated fusariosis remains rare in patients without neutropenia. We report a case of fungaemia in a 78-year-old French woman without definite immunodeficiency. Fusarium proliferatum grew from both central and peripheral blood cultures. Fever was the only clinical sign of the infection. An appropriate antifungal therapy with voriconazole led to the recovery of the patient. An environmental investigation was undertaken but failed to find a reservoir of Fusarium spores. A contaminated central venous catheter might have been the source of fungaemia.

Fusarium solani species complex associated with carapace lesions and branchitis in captive American horseshoe crabs Limulus polyphemus

Captive American horseshoe crabs Limulus polyphemus housed at the National Aquarium presented with a variety of shell and gill lesions over a 3 yr period. Carapace lesions were located on both the dorsal and ventral prosoma and opisthosoma and included multifocal circular areas of tan discoloration, ulcerations, and/or pitting lesions, extending from superficial to full thickness. Gill lesions involved both the book gill cover (operculum) and individual book gill leaflets and included multifocal circular areas of tan discoloration, tan to off-white opaque proliferative lesions, and/or areas of black discoloration. Histopathology revealed fungal hyphae, with variable morphology throughout the thickened and irregular cuticle of the carapace and occasionally penetrating into subcuticular tissues, with associated amebocytic inflammation. Book gill leaflets were infiltrated by fungal hyphae and contained necrotic debris and amebocytes. Thirty-eight of 39 animals (97%) evaluated via histopathological examination had intralesional fungal hyphae. Fungal cultures of carapace and gill lesions were attempted in 26 tissue samples from 15 individuals and were positive in 13 samples (50%), with 10 cultures (77%) yielding identification to genus. Fusarium sp. was identified in 8 of the 10 cultures (80%) via culture morphology. The Fusarium solani species complex was confirmed in 6 of these 8 (75%) via polymerase chain reaction amplification of 2 different ribosomal-specific sequences of isolated fungal DNA. Ante-mortem systemic and topical treatments were performed on some affected individuals, but no appreciable change in lesions was observed. Mycotic dermatitis and branchitis are serious health issues for captive American horseshoe crabs.

Antifungal drug development: challenges, unmet clinical needs, and new approaches

Invasive, life-threatening fungal infections are an important cause of morbidity and mortality, particularly for patients with compromised immune function. The number of therapeutic options for the treatment of invasive fungal infections is quite limited when compared with those available to treat bacterial infections. Indeed, only three classes of molecules are currently used in clinical practice and only one new class of antifungal drugs has been developed in the last 30 years. Here we summarize the unmet clinical needs of current antifungal therapy, discuss challenges inherent to antifungal drug discovery and development, and review recent developments aimed at addressing some of these challenges.

Development of cycling probe-based real-time PCR system to detect Fusarium species and Fusarium solani species complex (FSSC)

In the present study, we developed a new real-time PCR system based on the cycling probe technology (CPT), which is composed of two single tube real-time PCR assays: the Fusarium genus-specific assay and the Fusarium solani species complex (FSSC)-specific assay with primers targeting the 28s ribosomal RNA gene. The Fusarium genus-specific assay was shown to be highly specific, detecting all reference Fusarium strains with no cross-reaction with other reference fungal strains, such as Aspergillus spp. and human DNA. The FSSC-specific assay also reacted very specifically with FSSC, except for a cross-reaction with Fusarium lunatum. To validate the real-time PCR system, we tested 87 clinical isolates of Fusarium spp. Identification results from the real-time PCR system were found to be 100% concordant with those from DNA sequencing of EF-1α gene. The sensitivity testing also demonstrated high sensitivity, enabling detection of one copy of standard DNA with good reproducibility. Furthermore, both assays were shown to be extremely sensitive even when fungal cells were mixed with human cells, detecting 3 germinated conidia spiked in 3mL of human blood. To apply our new real-time PCR system to the molecular diagnosis of fusariosis, we evaluated its efficacy using a mouse model of invasive F. solani infection. Plasma and whole blood samples of infected mice were tested using the real-time PCR system. The sensitivity of the real-time PCR system was found to be 100% (n=4) in plasma samples. In contrast, no amplification signal was detected in whole blood samples. This system could provide a rapid and precise diagnostic tool for early diagnosis, which is necessary for appropriate treatment and improvement of prognosis of disseminated fusariosis.

Fusarium infection: report of 26 cases and review of 97 cases from the literature

Fusarium species is a ubiquitous fungus that causes opportunistic infections. We present 26 cases of invasive fusariosis categorized according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria of fungal infections. All cases (20 proven and 6 probable) were treated from January 2000 until January 2010. We also review 97 cases reported since 2000. The most important risk factors for invasive fusariosis in our patients were compromised immune system, specifically lung transplantation (n = 6) and hematologic malignancies (n = 5), and burns (n = 7 patients with skin fusariosis), while the most commonly infected site was the skin in 11 of 26 patients. The mortality rates among our patients with disseminated, skin, and pulmonary fusariosis were 50%, 40%, and 37.5%, respectively. Fusarium solani was the most frequent species, isolated from 49% of literature cases. Blood cultures were positive in 82% of both current study and literature patients with disseminated fusariosis, while the remaining 16% had 2 noncontiguous sites of infection but negative blood cultures. Surgical removal of focal lesions was effective in both current study and literature cases. Skin lesions in immunocompromised patients should raise the suspicion for skin or disseminated fusariosis. The combination of medical monotherapy with voriconazole or amphotericin B and surgery in such cases is highly suggested.

MALDI-TOF mass spectrometry in the clinical mycology laboratory: identification of fungi and beyond

MALDI-TOF mass spectrometry (MS) is becoming essential in most clinical microbiology laboratories throughout the world. Its successful use is mainly attributable to the low operational costs, the universality and flexibility of detection, as well as the specificity and speed of analysis. Based on characteristic protein spectra obtained from intact cells - by means of simple, rapid and reproducible preanalytical and analytical protocols - MALDI-TOF MS allows a highly discriminatory identification of yeasts and filamentous fungi starting from colonies. Whenever used early, direct identification of yeasts from positive blood cultures has the potential to greatly shorten turnaround times and to improve laboratory diagnosis of fungemia. More recently, but still at an infancy stage, MALDI-TOF MS is used to perform strain typing and to determine antifungal drug susceptibility. In this article, the authors discuss how the MALDI-TOF MS technology is destined to become a powerful tool for routine mycological diagnostics.