Head-to-head comparison of the activities of currently available antifungal agents against 3,378 Spanish clinical isolates of yeasts and filamentous fungi

Saprochaete/Magnusiomyces: identification, virulence factors, and antifungal susceptibility of a challenging rare yeast

Saprochaete/Magnusiomyces is among rare yeasts which might emerge as causes of breakthrough infections and nosocomial outbreaks. Identification to the species level might be a challenge in clinical laboratories. Data on virulence factors are scarce and antifungal susceptibility testing methodology is not definite. The aim of this study was to confirm species identification of clinical Saprochaete/Magnusiomyces isolates, find out their virulence factors, and obtain antifungal minimum inhibitory concentrations with two reference methods. Of the 57 isolates included, 54 were Saprochaete capitata and four were Saprochaete clavata as identified by ID32C, MALDI-TOF MS, and sequencing. When tested using phenotypic methods, all isolates were negative for coagulase, hemolysis, acid proteinase, and phospholipase, 56.1% were positive for esterase, and 19.3% had intermediate surface hydrophobicity. All isolates formed biofilms, with 40.4% of the isolates producing more biomass than biofilm-positive reference strain Candida albicans MYA-274. Antifungal susceptibility testing needed an adjusted spectrophotometric inoculum than recommended in reference methods for Candida/Cryptococcus. In conclusion, Saprochaete/Magnusiomyces species could be identified using methods available in the clinical laboratories. Despite the disadvantages of the phenotypic methods, esterase positivity was observed for the first time. A high biomass production was observed in biofilms. The need for standardization of antifungal susceptibility testing was brought to attention.

Fusarium solani species complex infection treated with posaconazole in a liver transplantation patient; a case report

Although Fusarium spp. rarely cause infections in healthy people, they can cause fusariosis, particularly in neutropenic hematological malignancies, bone marrow transplant patients, and immunocompromised patients, such as those with acquired immune deficiency syndrome (AIDS), and rarely in solid organ transplant recipients. Here, we present a case of a liver transplant recipient with F. solani species complex (FSSC) infection treated with posaconazole. A 61-year-old man presented with multiple itchy, painful, palpable, irregular, subcutaneous nodules on the right leg and total dystrophic onychomycosis in the right toenails. Incisional skin biopsies of the lesions were performed, and the samples were sent to the pathology and mycology laboratories for analysis. The clinical isolate was identified as FSSC using phenotypic, matrix-assisted laser desorption/ionization-time of flight mass spectrometry, and genotypic methods. Liposomal amphotericin B could not be administered owing to the development of side effects; hence, the patient was treated with posaconazole for 4 months. While some nodular lesions disappeared completely under this treatment, the others showed dimensional regression. This is the first case of FSSC infection with skin and nail involvement in a non-neutropenic, liver transplant patient in Turkey. Fusariosis may develop with rare species, such as FSSC, as first reported in this case of a liver transplant patient. Regardless of the species, amphotericin B is the first choice for treating fusariosis; however, posaconazole is an effective and safe alternative to amphotericin B.

Successful Use of Fosmanogepix for Treatment of Rare Highly Resistant Cutaneous Fusariosis in a Pediatric Patient With STAT3 Hyper-Immunoglobulin E Syndrome and End-Stage Kidney Disease

We describe the successful use of the novel antifungal drug fosmanogepix to treat a chronic case of multidrug-resistant cutaneous Fusarium suttonianum infection in a pediatric patient with STAT3 hyper-IgE syndrome and end-stage kidney disease on peritoneal dialysis.

Diagnosis and Treatment of Fungal Infections in Lung Transplant Recipients

Fungal infections are a significant source of morbidity in the lung transplant population via direct allograft damage and predisposing patients to the development of chronic lung allograft dysfunction. Prompt diagnosis and treatment are imperative to limit allograft damage. This review article discusses incidence, risk factors, and symptoms with a specific focus on diagnostic and treatment strategies in the lung transplant population for fungal infections caused by Aspergillus, Candida, Coccidioides, Histoplasma, Blastomyces, Scedosporium/Lomentospora, Fusarium, and Pneumocystis jirovecii. Evidence for the use of newer triazole and inhaled antifungals to treat isolated pulmonary fungal infections in lung transplant recipients is also discussed.

Non-Aspergillus Hyaline Molds: A Host-Based Perspective of Emerging Pathogenic Fungi Causing Sinopulmonary Diseases

The incidence of invasive sino-pulmonary diseases due to non-Aspergillus hyaline molds is increasing due to an enlarging and evolving population of immunosuppressed hosts as well as improvements in the capabilities of molecular-based diagnostics. Herein, we review the following opportunistic pathogens known to cause sinopulmonary disease, the most common manifestation of hyalohyphomycosis: Fusarium spp., Scedosporium spp., Lomentospora prolificans, Scopulariopsis spp., Trichoderma spp., Acremonium spp., Paecilomyces variotii, Purpureocillium lilacinum, Rasamsonia argillacea species complex, Arthrographis kalrae, and Penicillium species. To facilitate an understanding of the epidemiology and clinical features of sino-pulmonary hyalohyphomycoses in the context of host immune impairment, we utilized a host-based approach encompassing the following underlying conditions: neutropenia, hematologic malignancy, hematopoietic and solid organ transplantation, chronic granulomatous disease, acquired immunodeficiency syndrome, cystic fibrosis, and healthy individuals who sustain burns, trauma, or iatrogenic exposures. We further summarize the pre-clinical and clinical data informing antifungal management for each pathogen and consider the role of adjunctive surgery and/or immunomodulatory treatments to optimize patient outcome.

Atypical pulmonary phaeohyphomycosis due to Aureobasidium spp. - case report and brief literature review

We report on a case of probable invasive Auerobasidium spp. pulmonary infection in a patient with myelodysplastic syndrome. The patient was successfully treated with liposomal amphotericin B monotherapy, with transition to orally administered isavuconazole. This case shows an atypical initial radiological presentation with diffuse ground-glass opacities, as previously demonstrated in cases of Aureobasidium spp. hypersensitivity pneumonitis. Moreover this case further highlights the difficulties associated with the diagnosis and complexity in the management of Aureobasidium spp. infections.

Fusarium proliferatum-induced chronic lip ulcer: successful treatment with itraconazole: a case report

Background

Fusarium species are saprophytic fungi with a worldwide distribution. These fungi cause various infections among immunocompromised patients; however, they can also involve immunocompetent individuals.

Case presentation

We report a case of a 41-year-old Iranian woman who presented with ulcerative lesions on her lips 10 months ago. She had a long history of anxiety but had no history of classical risk factors such as trauma, cosmetic lip tattoo, burning in her lips, smoking or use of alcohol and opium. A skin biopsy from the lower lip was performed and sent for microbiological examinations. Hyaline septate hyphae were seen on direct microscopy with potassium hydroxide. The clinical specimen was subcultured on sabouraud dextrose agar with chloramphenicol and prepared for antifungal susceptibility testing and molecular identification. Considering the minimum inhibitory concentrations (MIC) for antifungals, itraconazole (100 mg orally twice a day) was started for her, and after 2 months, the lesions were treated. She followed up for 3 months, and no signs of disease recurrence were observed.

Conclusions

Selecting an appropriate treatment strategy according to the laboratory assessments is essential in clinical practice and the management of rare infections to prevent related mortality and morbidity of opportunistic fungal infections.

Paecilomyces/Purpureocillium Infection in Children, Case Report, and Review of the Literature

Paecilomyces/Purpureocillium has recently been recognized as an emerging human pathogen, causing serious infection in immunocompromised and immunocompetent patients. Several predisposing factors have been reported, including foreign body implants, previous surgery, or trauma. Treatment with antifungal drugs often fails as species-specific differences in antifungal susceptibilities are one of the management challenges. Surgical debridement with or without antifungal therapy was sufficient to cure the infection in a few reported cases. Nonetheless, the surgical approach has been found to decrease the chance of dissemination and recurrence. Here, we report the first pediatric patient with chronic osteomyelitis of the femur secondary to Paecilomyces species, with no predisposing risk factors. Our case was successfully treated with a combination of antifungal therapy and surgical debridement. Additionally, we describe the first extensive literature review of previously reported Paecilomyces/Purpureocillium species infections in pediatric age groups.

Fungemia due to Aureobasidium pullulans

Aureobasidium pullulans is a yeast-like dematiaceous fungus ubiquitous in nature. It is a rare cause of skin and soft tissue infection, peritonitis, and catheter-related fungemia in certain human hosts. We report a case of recurrent A. pullulans catheter-related fungemia that was successfully treated with caspofungin, posaconazole, and catheter removal.

Mucormycosis Amid COVID-19 Crisis: Pathogenesis, Diagnosis, and Novel Treatment Strategies to Combat the Spread

The havoc unleashed by COVID-19 pandemic has paved way for secondary ominous fungal infections like Mucormycosis. It is caused by a class of opportunistic pathogens from the order Mucorales. Fatality rates due to this contagious infection are extremely high. Numerous clinical manifestations result in damage to multiple organs subject to the patient's underlying condition. Lack of a proper detection method and reliable treatment has made the management of this infection troublesome. Several reports studying the behavior pattern of Mucorales inside the host by modulation of its defense mechanisms have helped in understanding the pathogenesis of this angio-invasive infection. Many recent advances in diagnosis and treatment of this fungal infection have not been much beneficial. Therefore, there is a need to foster more viable strategies. This article summarizes current and imminent approaches that could aid effective management of these secondary infections in these times of global pandemic. It is foreseen that the development of newer antifungal drugs, antimicrobial peptides, and nanotechnology-based approaches for drug delivery would help combat this infection and curb its spread.

Bloodstream infections caused by Magnusiomyces capitatus and Magnusiomyces clavatus: epidemiological, clinical and microbiological features of two emerging yeast species

BACKGROUND

Magnusiomyces clavatus and Magnusiomyces capitatus are emerging yeasts with intrinsic resistance to many commonly used antifungal agents. Identification is difficult, and determination of susceptibility patterns with commercial and reference methods is equally challenging. For this reason, few data on invasive infections by Magnusiomyces spp. are available.

OBJECTIVES

To determine the epidemiology and susceptibility of Magnusiomyces isolates from bloodstream infections (BSI) isolated in Germany and Austria from 2001-2020.

METHODS

In seven institutions a total of 34 Magnusiomyces BSI were identified. Identification was done by ITS sequencing and MALDI-TOF MS. Antifungal susceptibility was determined by EUCAST broth microdilution and gradient tests.

RESULTS

Of the 34 isolates, M. clavatus was more common (N=24) compared to M. capitatus (N=10). BSI by Magnusiomyces spp. were more common in men (62%) and mostly occurred in patients with haemato-oncological malignancies (79%). The highest in vitro antifungal activity against M. clavatus/M. capitatus was observed for voriconazole (MIC₅₀ 0.03/0.125 mg/L), followed by posaconazole (MIC₅₀ 0.125/0.25 mg/L). M. clavatus isolates showed overall lower MICs compared to M. capitatus. With the exception of amphotericin B, low essential agreement between gradient test and microdilution was recorded for all antifungals (0-70%). Both species showed distinct morphologic traits on ChromAgar Orientation and Columbia blood agar, which can be used for differentiation if no MALDI-TOF or molecular identification is available.

CONCLUSION

Most BSI were caused by M. clavatus. The lowest MICs were recorded for voriconazole. Gradient tests demonstrated unacceptably low agreement and should preferably not be used for susceptibility testing of Magnusiomyces spp.

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.

[Systemic antifungal drugs]

Invasive fungal infections have increased over the last decades and the therapeutic choices to treat them are limited. The antifungal agents currently available are useful and have optimal in vitro activity; however, their activity can be lowered due to the development of fungal resistance. The increase in primary or secondary resistance to some antifungal drugs has led to the search of alternatives such as the combination of drugs or the development of new antifungals. In this paper, the activity of the main families of antifungal drugs, polyenes, azoles, echinocandins, 5-fluorocytosine and other new antifungal drugs, are reviewed. The main resistance mechanisms developed by fungi are also described.

Molecular and MALDI-ToF MS differentiation and antifungal susceptibility of prevalent clinical Fusarium species in China

BACKGROUND

Fusarium species are emerging causative agents of superficial and disseminated human infections. Early diagnosis and treatment contribute to better prognosis of severe infection.

OBJECTIVES

To detect the effectiveness of matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-ToF MS) for Fusarium identification, and evaluate the susceptibility profiles to clinical available antifungals.

METHODS

All 203 clinical Fusarium isolates and 25 environmental isolates were identified by using translation elongation factor 1-alpha (TEF1) and RNA polymerase subunit II (RPB2) sequencing and MALDI-ToF MS. Antifungal susceptibility testing was determined by a microdilution method following the CLSI approved standard M38-A3 document.

RESULTS

Correct identification rates at the species and genus levels were 89.04% (203/228) and 95.18% (217/228), respectively, using Bruker Filamentous Fungi Library 1.0 combined with the novel database. Seven species complexes with 19 Fusarium species were identified, including F. solani (59.21%, n = 135), F. verticillioides (17.54%, n = 40), F. proliferatum (6.58%, n = 15) and F. oxysporum (4.39%, n = 10). Four uncommon species complexes (F. incarnatum-equiseti SC, F. dimerum SC, F. redolens SC and F. sporotrichioides SC) were also identified. A high degree of antifungal resistance was observed. Fusarium isolates exhibited lower MICs to luliconazole and terbinafine compared with amphotericin B and voriconazole, which in turn were significantly more active than amorolfine, fluconazole and itraconazole.

CONCLUSIONS

MALDI-ToF MS showed good performance in Fusarium species with an adapted Bruker library and expanded database. Fusarium isolates exhibited lower MICs to luliconazole and terbinafine compared to amphotericin B and voriconazole.

Novel Penicillium species causing disseminated disease in a Labrador Retriever dog

This report describes the phenotypic characteristics of a novel Penicillium species, Penicillium labradorum, isolated from a 3-year-old male, castrated, Labrador retriever with disseminated fungal disease. The dog's presenting clinical signs included lethargy, lymphadenopathy, tachypnea, moderate pitting edema, and nonweight bearing lameness associated with the right hind limb. Fine-needle aspirate biopsies from the sublumbar and prescapular lymph nodes were initially examined. The cytologic findings were consistent with pyogranulomatous inflammation with abundant extracellular and phagocytized fungal fragments and hyphae. Based on the morphology of the organisms and lack of endogenous pigment, hyalohyphomycosis was considered most likely, with Fusarium, Penicillium, and Paecilomyces species being considerations. Fungal isolates were obtained via culture of samples from the lymph nodes, and molecular identification testing originally identified an undescribed Penicillium species belonging to the Penicillium section Exilicaulis. BLAST searches and phylogenetic analyses performed approximately 1 year and 9 months after the isolation date revealed an isolate within the Penicillium parvum clade in the Penicillium section Exilicaulis but phylogenetically distant from the other species in the section, thus representing a new species, Penicillium labradorum. Antifungal susceptibility testing was also performed on the isolate and low minimum inhibitory concentrations were observed with terbinafine, voriconazole, and posaconazole, while in vitro resistance was observed with fluconazole. The dog had been previously treated with fluconazole, itraconazole, amphotericin B lipid complex, voriconazole, and terbinafine. Approximately 587 days after the initial diagnosis, the dog was euthanized due to worsening of clinical signs and concerns for quality of life.

Development, optimization and characterization of nanoemulsion loaded with clove oil-naftifine antifungal for the management of tinea

Tinea is a common superficial infection caused by keratinophylic fungi called dermatophytes. The objective of the current investigation was to develop and optimize a self-nanoemulsion drug delivery system (SENDDs) using clove oil loaded with naftifine (NF). Clove oil possesses good anti-inflammatory and antifungal properties that can support naftifine action. Box–Behnken designs were used to prepare plain and naftifine loaded SENDDs. The plain SENDDs were evaluated for their globule size. The medicated formulations (NF-CO-SENDDs) were characterized by measuring their globular size, ex vivo % NF permeated, level of interleukin-31 in rats, and antifungal activity. The optimum clove oil level was found to be 10–17%, while NF-CO-SENDDs formulations displayed globular sizes ranging from 119 to 310 nm. The statistical design confirmed the synergistic effect of clove oil and NF in the treatment of fungal infections, confirming that the anti-inflammatory effect of clove oil can counteract the side effects of NF. The optimized formulation composed of 14% clove oil, 12.5 mg Naftifine, and prepared with an Smix ratio equaling 3:1, exhibited good antifungal and anti-inflammatory activity, achieving up to 2-, 3-, 5.75-, and 2.74-fold increases in the amount of permeated NF, steady-state flux, permeability, and diffusion coefficients, respectively, compared with a commercial product. Moreover, the optimum formulation revealed an adequate zeta potential value of 28.31 ± 1.37 mV and showed reasonable stability with no or mild signs of skin sensitivity. Therefore, the designed nanoemulsions containing a combination of clove oil and naftifine could be considered promising delivery systems for the treatment of tinea.

Prenylated Trans-Cinnamic Esters and Ethers against Clinical Fusarium spp.: Repositioning of Natural Compounds in Antimicrobial Discovery

Onychomycosis is a common nail infection mainly caused by species belonging to the F. oxysporum, F. solani, and F. fujikuroi species complexes. The aim of this study was to evaluate the in vitro susceptibility of six representative strains of clinically relevant Fusarium spp. toward a set of natural-occurring hydroxycinnamic acids and their derivatives with the purpose to develop naturally occurring products in order to cope with emerging resistance phenomena. By introducing a prenylated chain at one of the hydroxy groups of trans-cinnamic acids 1–3, ten prenylated derivatives (coded 4–13) were preliminarily investigated in solid Fusarium minimal medium (FMM). Minimal inhibitory concentration (MIC) and lethal dose 50 (LD₅₀) values were then determined in liquid FMM for the most active selected antifungal p-coumaric acid 3,3′-dimethyl allyl ester 13, in comparison with the conventional fungicides terbinafine (TRB) and amphotericin B (AmB), through the quantification of the fungal growth. Significant growth inhibition was observed for prenylated derivatives 4–13, evidencing ester 13 as the most active. This compound presented MIC and LD₅₀ values (62–250 µM and 7.8–125 µM, respectively) comparable to those determined for TRB and AmB in the majority of the tested pathogenic strains. The position and size of the prenylated chain and the presence of a free phenol OH group appear crucial for the antifungal activity. This work represents the first report on the activity of prenylated cinnamic esters and ethers against clinical Fusarium spp. and opens new avenues in the development of alternative antifungal compounds based on a drug repositioning strategy.

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.

Scedosporium Apiospermum: Rare Cause of Brain Abscess in an Immunocompetent Patient

Scedosporium apiospermum is a filamentous fungus causing a broad spectrum of clinical diseases especially in those who are immunocompromised. The common sites involved are lungs, skin, sinuses, eyes, bones, joints, and central nervous system (CNS). CNS is involved in invasive Scedosporiosis in the form of a cerebral abscess. An antecedent event of either near-drowning or history of some trauma is present in the majority of the cases where the patients' immune response remains intact. Prognosis is generally poor since the majority of the patients have coexistent medical morbidity. Surgical drainage followed by adjuvant antifungal, i.e., voriconazole therapy offers the best possible chance for survival in these patients. This case report discusses a rare event of brain abscess caused by S. apiospermum in an immunocompetent patient without any preceding precipitating factor.

Disseminated Intravascular Infection Caused by Paecilomyces variotii: Case Report and Review of the Literature

Paecilomyces variotii is a ubiquitous environmental saprophyte with worldwide distribution. Commonly found in soil and decomposing organic material [1, 2], P. variotii can also be isolated from drinking water [3] and indoor and outdoor air [4-6]. In immunocompetent hosts, P. variotii has been reported as a cause of locally invasive disease including prosthetic valve endocarditis [7, 8], endophthalmitis [9, 10], rhinosinusitis [11, 12], and dialysis-associated peritonitis [13, 14]. In contrast, disseminated infections are more commonly reported in immunocompromised patients, including those with chronic granulomatous disease [15], solid malignancy [16], acute leukemia [17], lymphoma [18], multiple myeloma [19], and after stem cell transplant for myelodysplasia [20]. In 1 case series examining invasive infections by non-Aspergillus molds, P. variotii was the most common cause after Fusarium spp. [21]. Here, we present the case of an immunocompetent patient with extensive intravascular infection involving prosthetic material. We describe successful induction therapy with combination antifungals and extended suppression with posaconazole with clinical quiescence and eventual normalization of serum fungal biomarkers.

Diffuse primary cutaneous infection by Alternaria alternata in a liver transplant recipient with pulmonary nocardiosis: Importance of prompt identification for clinical resolution

Fungal infections are rare in the general population but are an emerging cause of disease in immunosuppressed patients, especially solid organ transplant recipients. Here, we report the case of a female Caucasian liver transplant patient who developed pulmonary nocardiosis two months after an episode of liver rejection. At the time of lung nocardiosis, she was being treated with tacrolimus and corticosteroids and suffered from diffuse papular skin lesions. She was initially suspected of having a cutaneous nocardial infection but culture examination revealed the presence of a dematiaceous fungus; Alternaria alternata. The prompt identification of the fungus and administration of oral Voriconazole resolved the skin infection with complete remission.

Treatment of Fungal Peritonitis with a Combination of Intravenous Amphotericin B and Oral Flucytosine, and Delayed Catheter Replacement in Continuous Ambulatory Peritoneal Dialysis

Background

Fungal peritonitis (FP) is associated with significant mortality and high risk of peritoneal failure. The optimum treatment for peritoneal dialysis (PD)-associated FP remains unclear. Since January 2000 we have been treating FP with a combination of intravenous amphotericin B and oral flucytosine, together with deferred catheter replacement. We examined the clinical course and outcome of the FP patients treated with this approach (study group). An outcome comparison was also made to an alternatively treated historic cohort (control group).

Methods

This was a single-center retrospective study. The clinical course and outcome of 13 consecutive episodes of FP occurring in 13 patients treated between January 2000 and April 2005 with the study approach were examined. The patients were treated with an incremental dose of intravenous amphotericin B to a target dose of 0.75 – 1 mg/kg body weight/day, and oral flucytosine 1 g/day upon a diagnosis of FP at 3.77 ± 0.93 days from presentation. Replacement of the peritoneal catheter was intended after complete clearing of effluent, after which, antifungal chemotherapy was continued for another 1 – 2 weeks. Their outcome was compared with 14 historic controls that were treated between April 1995 and December 1999.

Results

Mean age of the study group was 58.7 ± 13.2 years; male-to-female ratio was 2:11; 6 (46.1%) were diabetic. All FP were caused by Candida species ( C. albicans, 2; C. parapsilosis, 8; C. glabrata, 3). Two (15.4%) patients died before resolution of the peritonitis. The dialysate effluent cleared in 11 patients (84.6%) after 13.2 ± 3.3 days of treatment, but 2 patients died of acute myocardial infarction before catheter replacement. Nine patients had their catheters replaced at day 26.7 ± 7.7 of treatment; all 9 returned to PD after a total of 31 ± 12.2 days of antifungal chemotherapy. Reversible liver dysfunction was common with this regimen. When compared with the 14 cases in the historic control group ( Candida species, 13; Trichosporon, 1), who were treated with amphotericin B, fluconazole, or a combination of the two, and the majority (78.6%) of whose catheters were removed before day 10 of presentation, the study group appeared to have a lower technique failure rate (30.8% vs 78.6%, p = 0.013) and similar all-cause mortality (30.7% vs 28.5%, p = NS), FP-related mortality (15.4% vs 28.5%, p = NS), and length of hospitalization (48.5 ± 30.2 vs 57.0 ± 37.7 days, p = NS). However, a significantly earlier commencement of antifungal treatment in the study group (3.8 ± 0.9 vs 5.8 ± 2.4 days, p = 0.012) could be an important confounder of outcome.

Conclusions

Combination of intravenous amphotericin B and oral flucytosine with deferred catheter replacement appears to be associated with a relatively low incidence of PD technique failure, without affecting mortality in patients suffering from FP due to yeasts in this preliminary study. Nonetheless, drug-induced hepatic dysfunction was common; close monitoring during treatment is of paramount importance. The reasons accounting for the observed distinctive outcome remain unclear and further study is required to confirm the results and to investigate for the underlying mechanism.

Fungal Infections of the Stem Cell Transplant Recipient and Hematologic Malignancy Patients

Despite advances in chemotherapy and supportive care, morbidity and mortality remain high for patients with hematologic malignancies (HMs). Those who require hematopoietic stem cell transplantation (HSCT) often require significant immunosuppression and are subject to a variety of complications. These patients carry multiple risk factors for infectious complications, including the development of invasive fungal infections, compared with the general population. Because antifungal prophylaxis has been widely adopted, there has been a shift away from invasive candidiasis toward invasive mold infections, including breakthrough infections. For patients with HM and HSCT, we outline the epidemiology, manifestations, diagnosis, and treatment of invasive fungal infections.

Infections caused by Scedosporium/Lomentospora species: Clinical and microbiological findings in 21 cases

The clinical and microbiological characteristics of infections caused by Scedosporium/ Lomentospora species in 21 patients are described. We searched retrospectively the records for Scedosporium/ Lomentospora species seen at the University Hospital Virgen de las Nieves from 2006 to 2017. Out of them, 16 were male; mean age at diagnosis was 57.8 (±SD 15) years; all patients had risk factors for fungal infection such as corticosteroids and/or immunosuppressive treatment in 18 (85.7%) patients, pulmonary diseases in seven (33.3%) cases, hematological malignancies in six (28.5%), and organ transplantation in three (14.2%) patients. Most patients had infection in the lung/pleura (17/80.9%); cough was present in 12 patients and dyspnea in another 12, and the mean interval until diagnosis was 13.6 days. The most frequent species was S. apiospermum/S. boydii in 14 patients (66.6%), followed by L. prolificans in seven. The diagnosis was obtained from sputum in 12 (57.1%) cases, followed by pleural fluid and bronchoalveolar lavage in two of each. The most frequently used antifungals were voriconazole and amphotericin B, but combination of more than one antifungal drug was only used in three patients. Ten patients were cured, and six patients died as a consequence of the infection; three patients had chronic infection. In general, infections caused by Scedosporium/Lomentospora species are rare, serious, and difficult to diagnose and treat, having a high index or mortality especially in those caused by L. prolificans.

Pulmonary Scedosporium apiospermum Infection with Pulmonary Tumorlet in an Immunocompetent Patient

Scedosporium apiospermum is an opportunistic fungus that can cause various types of infections, including localized infections and life-threatening disseminated infections, particularly in immunocompromised patients. Treatment is especially challenging due to its multidrug resistance. We herein report the case of a 73-year-old woman who was non-immunocompromised but developed S. apiospermum lung infection and a pulmonary tumorlet. To our knowledge, this is the first report of the coexistence of pulmonary S. apiospermum infection and tumorlet. The lung lesion was successfully treated by surgical excision without any antifungal agents, and no recurrence of the tumorlet or S. apiospermum infection has occurred.

Angioinvasive fungal infections impacting the skin: Diagnosis, management, and complications

As discussed in the first article in this continuing medical education series, angioinvasive fungal infections pose a significant risk to immunocompromised and immunocompetent patients alike, with a potential for severe morbidity and high mortality. The first article in this series focused on the epidemiology and clinical presentation of these infections; this article discusses the diagnosis, management, and potential complications of these infections. The mainstay diagnostic tests (positive tissue culture with histologic confirmation) are often supplemented with serum biomarker assays and molecular testing (eg, quantitative polymerase chain reaction analysis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry) to ensure proper speciation. When an angioinvasive fungal infection is suspected or diagnosed, further workup for visceral involvement also is essential and may partially depend on the organism. Different fungal organisms have varied susceptibilities to antifungal agents, and knowledge on optimal treatment regimens is important to avoid the potential complications associated with undertreated or untreated fungal infections.

Disseminated fungal infection by Aureobasidium pullulans in a renal transplant recipient

Renal transplant recipients are on long-term potent immunosuppressive therapy, which makes them highly vulnerable to opportunistic fungal infections. Dematiaceous, or dark-pigmented saprophytic fungi, are being increasingly seen as opportunistic pathogens of mycoses in immunosuppressed patients. One of these is Aureobasidium pullulans, which is a black yeast-like dematiaceous fungus found ubiquitously in the environment that can cause various opportunistic human infections. Most infections occur by traumatic inoculation, such as keratitis and cutaneous lesions; disseminated mycoses are very rare and occur only in severely immunocompromised patients. We report a case of disseminated fungal infection due to A. pullulans in a pediatric patient who underwent renal transplant. The use of voriconazole and vacuum-assisted closure along with surgical drainage most likely contributed to the patient's positive outcome.

Airborne transmission of invasive fusariosis in patients with hematologic malignancies

From 2006 to 2013, an increasing incidence of fusariosis was observed in the hematologic patients of our University Hospital. We suspected of an environmental source, and the indoor hospital air was investigated as a potential source of the fungemia. Air samplings were performed in the hematology and bone marrow transplant (BMT) wards using an air sampler with pre-defined air volumes. To study the molecular relationship among environmental and clinical isolates, 18 Fusarium spp. recovered from blood cultures were included in the study. DNA sequencing of a partial portion of TEF1α gene was performed for molecular identification. Molecular typing was carried out by multi-locus sequence typing (MLST) using a four-gene scheme: TEF1α, rDNA, RPB1 and RPB2. One hundred four isolates were recovered from the air of the hematology (n = 76) and the BMT (n = 28) wards. Fusarium isolates from the air were from five species complexes: Fusarium fujikuroi (FFSC, n = 56), Fusarium incarnatum-equiseti (FIESC, n = 24), Fusarium solani (FSSC, n = 13), Fusarium chlamydosporum (FCSC, n = 10), and Fusarium oxysporum (FOSC, n = 1). Fifteen Fusarium isolates recovered from blood belonged to FSSC, and three to FFSC. MLST identified the same sequence type (ST) in clinical and environmental isolates. ST1 was found in 5 isolates from blood and in 7 from the air, both identified as FSSC (Fusarium petroliphilum). STn1 was found in one isolate from blood and in one from the air, both identified as FFSC (Fusarium napiforme). F. napiforme was isolated from the air of the hospital room of the patient with fungemia due to F. napiforme. These findings suggested a possible clonal origin of the Fusarium spp. recovered from air and bloodcultures. In conclusion, our study found a diversity of Fusarium species in the air of our hospital, and a possible role of the air as source of systemic fusariosis in our immunocompromised patients.

Design of Two Alternative Routes for the Synthesis of Naftifine and Analogues as Potential Antifungal Agents

Two practical and efficient approaches have been implemented as alternative procedures for the synthesis of naftifine and novel diversely substituted analogues 16 and 20 in good to excellent yields, mediated by Mannich-type reactions as the key step of the processes. In these approaches, the γ-aminoalcohols 15 and 19 were obtained as the key intermediates and their subsequent dehydration catalyzed either by Brønsted acids like H₂SO₄ and HCl or Lewis acid like AlCl₃, respectively, led to naftifine, along with the target allylamines 16 and 20. The antifungal assay results showed that intermediates 18 (bearing both a β-aminoketo- and N-methyl functionalities in their structures) and products 20 were the most active. Particularly, structures 18b, 18c, and the allylamine 20c showed the lowest MIC values, in the 0.5-7.8 µg/mL range, against the dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes. Interesting enough, compound 18b bearing a 4-Br as the substituent of the phenyl ring, also displayed high activity against Candida albicans and Cryptococcus neoformans with MIC₈₀ = 7.8 µg/mL, being fungicide rather than fungistatic with a relevant MFC value = 15.6 µg/mL against C. neoformans.

Biofilm Formation and Resistance to Fungicides in Clinically Relevant Members of the Fungal Genus Fusarium

Clinically relevant members of the fungal genus, Fusarium, exhibit an extraordinary genetic diversity and cause a wide spectrum of infections in both healthy individuals and immunocompromised patients. Generally, Fusarium species are intrinsically resistant to all systemic antifungals. We investigated whether the presence or absence of the ability to produce biofilms across and within Fusarium species complexes is linked to higher resistance against antifungals. A collection of 41 Fusarium strains, obtained from 38 patients with superficial and systemic infections, and three infected crops, were tested, including 25 species within the Fusarium fujikuroi species complex, 14 from the Fusarium solani species complex (FSSC), one Fusarium dimerum species complex, and one Fusarium oxysporum species complex isolate. Of all isolates tested, only seven strains from two species of FSSC, five F. petroliphilum and two F. keratoplasticum strains, recovered from blood, nail scrapings, and nasal biopsy samples, could produce biofilms under the tested conditions. In the liquid culture tested, sessile biofilm-forming Fusarium strains exhibited elevated minimum inhibitory concentrations (MICs) for amphotericin B, voriconazole, and posaconazole, compared to their planktonic counterparts, indicating that the ability to form biofilm may significantly increase resistance. Collectively, this suggests that once a surface adherent biofilm has been established, therapies designed to kill planktonic cells of Fusarium are ineffective.

Assessment of occupational exposure to azole resistant fungi in 10 Portuguese bakeries

Occupational exposure to bioaerosols resulting from handling of flour dust and raw materials in bakeries is associated with health problems. The emergence of azole-resistant fungal species in the environment is thought to be related with the use of azole fungicides in cereal crops and prevention of postharvest spoilage. As raw materials used in bakeries are commonly exposed to azoles, we investigated the mycobiota and azole-resistant fungi prevalence in this occupational environment. Ten Portuguese bakeries were assessed through electrostatic dust cloth (EDC, n = 27), settled dust (n = 7), and raw material (n = 26) samples. Samples were inoculated in malt extract agar (2%) (MEA) with chloramphenicol (0.05 g/L) and in dichloran glycerol (DG18), and onto Saboraud screening media supplemented with 4 mg/L itraconazole, 1 mg/L voriconazole, or 0.5 mg/L posaconazole, and incubated for 3-5 days at 27 °C. Except for one out of the ten analyzed bakeries, Cladosporium sp., Penicillium sp., and Aspergillus sp. were the most prevalent fungi identified. Aspergillus sp. and Mucorales order were identified in raw materials with both media, whereas Penicillium sp. was identified in DG18 only. Azole-resistant species were identified in the environment (EDC) and, to a lower extent, in raw materials, including Aspergillus sp. and Mucorales. The presence of azole-resistant fungal species in bakeries represents an occupational risk for workers. This study proposes complementary sampling methods for the evaluation of occupational exposure to mycobiota, and highlights the importance of studying the prevalence of azole-resistant strains in specific occupational environments.

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.

Combination therapy for the treatment of pulmonary mold infections

INTRODUCTION

Pulmonary mold infections are caused by ubiquitous organisms found in soil, water, and decaying vegetation, including Aspergillus spp., the Mucormycetes, hyaline molds, and dematiaceous (black) molds. Areas covered: These infections are often a challenge to diagnose and even more difficult to treat. Recently, antifungal combination therapy has emerged as a promising strategy to treat some forms of invasive mycoses, including pulmonary mold infections. Historically, this approach has been limited due to non-uniform interpretation criteria, variations in pharmacodynamic/pharmacokinetic properties of antifungals used in combination, and an inability to predict clinical success based on in vitro data and animal models. However, recent advances have helped mitigate some of these challenges. Expert commentary: In this paper, we explore what is known about the antifungal combination therapy in the treatment of pulmonary mold infections and explore how it may impact clinical practice. We pay particular attention to novel combinations and the challenges associated with the development of new antifungal agents.

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.

Does a triple combination have better activity than double combinations against multiresistant fungi? Experimental in vitro evaluation

In this study, the in vitro interactions of amphotericin B (AmB), voriconazole (VRC) and anidulafungin (AFG) in double and triple combinations against four species of multiresistant fungi (Fusarium solani, Lomentospora prolificans, Scopulariopsis brevicaulis and Scopulariopsis brumptii) were evaluated. In general, AmB combined with AFG was the most synergistic, especially against F. solani (7/8; 87.5%) when low concentrations of AmB were used, i.e. 0.125-0.5 µg/mL. The least active combination was AmB + VRC, with the lowest percentage of synergy against S. brevicaulis (2/11; 18.2%) and, in general, high concentrations of both antifungals were needed to achieve synergy. The triple combination was also highly synergistic against F. solani and S. brevicaulis, especially when the lowest concentrations of AmB were used, suggesting that use of combined therapies would reduce the toxicity of therapy. The triple combination was more effective than the double combinations in some cases, but not against all strains, suggesting that administration of three drugs is not always useful in the treatment of infections due to multiresistant fungi.

Pathogenic factors in Candida biofilm-related infectious diseases

Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various micro-organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm-related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida-formed biofilm.

Blood and tissue distribution of posaconazole in a rat model of invasive pulmonary aspergillosis

Posaconazole is the recommended prophylactic agent in patients at high risk of invasive fungal infection, since adequate drug levels seem to be reached in target sites despite the relatively low levels detected in blood. The objective of this study is to obtain pharmacokinetic (PK) information associated to blood and tissue distribution of posaconazole in an animal model of invasive pulmonary aspergillosis. The PK parameters in lung samples were systematically higher than in serum. After multiple-dose administration of posaconazole, a significant accumulation of the drug was evident in lung tissue. The PK behavior of posaconazole in this particular experimental model is similar to that observed in humans. Thus, we believe this model could be a valid tool to evaluate posaconazole exposure-response relationship.

Evaluation of the possible influence of trailing and paradoxical effects on the clinical outcome of patients with candidemia

OBJECTIVE

Paradoxical growth (PG) and trailing effect (TE) are frequently observed during antifungal susceptibility testing (AFST). These two phenomena interfere with the determination of the minimal inhibitory concentration (MIC). The aim of this study was to assess the clinical impact of TE and PG.

METHODS

We analysed the frequency of TE and PG of 690 Candida isolates collected from a population-based study performed in Spain (CANDIPOP) and correlated the results with clinical outcome of the patients.

RESULTS

Around 70% (484/690) of the isolates exhibited TE to azoles. Candida tropicalis showed the highest presence of TE (39/53 isolates exhibited residual growth >25% of control). No TE was seen in most of the isolates from the psilosis complex. PG was mainly associated with echinocandins. In patients treated with fluconazole within the first 48 hours after blood sampling (n = 221), the presence of TE to azoles tended to be associated with lower 30-day mortality (odds ratio (OR) 0.55, 95% confidence interval (CI) 0.25-1.00) but not with clinical failure (OR 0.85, 95% CI 0.45-1.54). In the subgroup of 117 patients treated with echinocandins, the presence of PG was not associated with patient's response to antifungal treatment (OR for 30-day mortality 1.63, 95% CI 0.76-4.03; OR for clinical failure 1.17, 95% CI 0.53-2.70).

CONCLUSIONS

TE or PG are widely expressed among Candida spp., although they do not seem to influence clinical outcome.

Breaking the Mold

Objective: To review the current literature for the pathogenesis of mucormycosis, discuss diagnostic strategies, and evaluate the efficacy of polyenes, triazoles, and echinocandins as pharmacological treatment options. Data Sources: An electronic literature search was conducted in PubMed using the MESH terms Rhizopus, zygomycetes, zygomycosis, Mucorales and mucormycosis, with search terms amphotericin B, micafungin, anidulafungin, caspofungin, extended infusion amphotericin B, liposomal amphotericin B, combination therapy, triazole, posaconazole, isavuconazole, diagnosis, and clinical manifestations.Study Selection and Data Extraction: Studies written in the English language from January 1960 to March 2016 were considered for this review article. All search results were reviewed, and the relevance of each article was determined by the authors independently. Data Synthesis: Mucormycosis is a rare invasive fungal infection with an exceedingly high mortality and few therapeutic options. It has a distinct predilection for invasion of endothelial cells in the vascular system, which is likely important in dissemination of disease from a primary focus of infection. Six distinct clinical syndromes can occur in susceptible hosts, including rhino-orbital-cerebral, pulmonary, gastrointestinal, cutaneous, widely disseminated, and miscellaneous infection. Conclusion: Diagnosis of mucormycosis is typically difficult to make based on imaging studies, sputum culture, bronchoalveolar lavage culture, or needle aspirate. Surgical debridement prior to dissemination of infection improves clinical outcomes. Surgery combined with early, high-dose systemic antifungal therapy yields greater than a 1.5-fold increase in survival rates. The Mucorales are inherently resistant to most widely used antifungal agents. Amphotericin B is appropriate for empirical therapy, whereas posaconazole and isavuconazole are best reserved for de-escalation, refractory cases, or patients intolerant to amphotericin B.

[Disseminated fungal infection due to Magnusiomyces capitatus in a liver graft patient]

Disseminated fungal infections due to Magnusiomyces capitatus are rare, occurring exclusively in immunocompromised patients. We report the first case in a liver transplant patient with chronic rejection and portal thrombosis who had a M. capitatus fungemia with a refractory septic shock. Despite an antibacterial and antifungal treatment with caspofungin empirical treatment, the patient died from multiple organ failure. Subsequently, mycological examinations of blood cultures, bronchoalveolar lavage fluid and urine were positive to M. capitatus identified by mass spectrometry and confirmed by sequencing respectively. The stain was resistant to caspofungin and fluconazole. The best treatment appears to be the combination of amphotericin B and voriconazole or amphotericin B and 5 fluorocytosine.

Antibiofilm activity of carboxymethyl chitosan on the biofilms of non-Candida albicans Candida species

Although most cases of candidiasis have been attributed to Candida albicans, non-C. albicans Candida species have been isolated in increasing numbers in patients. In this study, we determined the inhibition of carboxymethyl chitosan (CM-chitosan) on single and mixed species biofilm of non-albicans Candida species, including Candida tropicalis, Candida parapsilosis, Candida krusei and Candida glabrata. Biofilm by all tested species in microtiter plates were inhibited nearly 70%. CM-chitosan inhibited mixed species biofilm in microtiter plates and also on medical materials surfaces. To investigate the mechanism, the effect of CM-chitosan on cell viability and biofilm growth was employed. CM-chitosan inhibited Candida planktonic growth as well as adhesion. Further biofilm formation was inhibited with CM-chitosan added at 90min, 12h or 24h after biofilm initiation. CM-chitosan was not only able to inhibit the metabolic activity of Candida cells, but was also active upon the establishment and the development of biofilms.

Genotyping of Fusarium Isolates from Onychomycoses in Colombia: Detection of Two New Species Within the Fusarium solani Species Complex and In Vitro Antifungal Susceptibility Testing

Fusariosis have been increasing in Colombia in recent years, but its epidemiology is poorly known. We have morphologically and molecularly characterized 89 isolates of Fusarium obtained between 2010 and 2012 in the cities of Bogotá and Medellín. Using a multi-locus sequence analysis of rDNA internal transcribed spacer, a fragment of the translation elongation factor 1-alpha (Tef-1α) and of the RNA-dependent polymerase subunit II (Rpb2) genes, we identified the phylogenetic species and circulating haplotypes. Since most of the isolates studied were from onychomycoses (nearly 90 %), we carried out an epidemiological study to determine the risk factors associated with such infections. Five phylogenetic species of the Fusarium solani species complex (FSSC), i.e., F. falciforme, F. keratoplasticum, F. lichenicola, F. petroliphilum, and FSSC 6 as well as two of the Fusarium oxysporum species complex (FOSC), i.e., FOSC 3 and FOSC 4, were identified. The most prevalent species were FOSC 3 (38.2%) followed by F. keratoplasticum (33.7%). In addition, our isolates were distributed into 23 haplotypes (14 into FOSC and nine into FSSC). Two of the FSSC phylogenetic species and two haplotypes of FSSC were not described before. Our results demonstrate that recipients of pedicure treatments have a lower probability of acquiring onychomycosis than those not receiving such treatments. The antifungal susceptibility of all the isolates to five clinically available agents showed that amphotericin B was the most active drug, while the azoles exhibited lower in vitro activity.