Altered Pseudomonas Strategies to Inhibit Surface Aspergillus Colonies

Pseudomonas aeruginosa and Aspergillus fumigatus infections frequently co-localize in lungs of immunocompromised patients and individuals with cystic fibrosis (CF). The antifungal activity of P. aeruginosa has been described for its filtrates. Pyoverdine and pyocyanin are the principal antifungal P. aeruginosa molecules active against A. fumigatus biofilm metabolism present in iron-limited or iron-replete planktonic P. aeruginosa culture filtrates, respectively. Using various P. aeruginosa laboratory wild-type strains (PA14, PAO1, PAK), we found antifungal activity against Aspergillus colonies on agar. Comparing 36 PA14 and 7 PAO1 mutants, we found that mutants lacking both major siderophores, pyoverdine and pyochelin, display higher antifungal activity on agar than their wild types, while quorum sensing mutants lost antifungal activity. Addition of ferric iron, but not calcium or magnesium, reduced the antifungal effects of P. aeruginosa on agar, whereas iron-poor agar enhanced antifungal effects. Antifungal activity on agar was mediated by PQS and HHQ, via MvfR. Among the MvfR downstream factors, rhamnolipids and elastase were produced in larger quantities by pyoverdine–pyochelin double mutants and showed antifungal activity on agar. In summary, antifungal factors produced by P. aeruginosa on agar differ from those produced by bacteria grown in liquid cultures, are dependent on quorum sensing, and are downregulated by the availability of ferric iron. Rhamnolipids and elastase seem to be major mediators of Pseudomonas’ antifungal activity on a solid surface.

FDA Public Workshop Summary-Coccidioidomycosis (Valley Fever): Considerations for Development of Antifungal Drugs

Coccidioidomycosis is a fungal disease endemic to the southwestern United States, Mexico, and Central and South America. Prevalence rates are increasing steadily and new endemic areas of Coccidioides are emerging. Standard treatment is often administered for months to decades, and intolerance to medications and treatment failures are common. No new treatments for coccidioidomycosis have been approved in the U.S. in nearly 40 years. On August 5, 2020, the U.S. Food and Drug Administration convened experts in coccidioidomycosis from academia, industry, patient groups and other government agencies to discuss the disease landscape and strategies to facilitate product development for treatment of coccidioidomycosis. This paper summarizes the key topics concerning drug development for coccidioidomycosis presented by speakers and panelists during the workshop, such as unmet need, trial designs, endpoints, incentives, research and development support, and collaborations to facilitate antifungal drug development.

Nikkomycin Z against Disseminated Coccidioidomycosis in a Murine Model of Sustained-Release Dosing

Nikkomycin Z (nikZ) is a chitin synthase inhibitor. Efficacy against Coccidioides has been demonstrated in animal models of pulmonary or brain infection. Its short half-life in mice and in humans would necessitate divided daily dosing. We assayed nikZ efficacy in disseminated coccidioidomycosis (in a reduction of CFU design) and whether sustained release might be useful. Mice were challenged intravenously with low or high arthroconidial inocula. Fluconazole, clinically the most commonly used anticoccidioidal drug, was compared (gavage) at high dose to a dose range of nikZ administered intraperitoneally or, to mimic sustained release, administered continuously in drinking water. Therapy was given for 5 days. In vitro, both fluconazole and nikZ inhibited the isolate studied; nikZ was fungicidal. Oral nikZ therapy gave similar results to intraperitoneal nikZ and sterilized infection in most animals after low-inoculum challenge. In both challenges, oral nikZ produced greater reduction of CFU in organs (lung, liver, and spleen) than fluconazole. Oral nikZ doses of ≥200 mg/kg of body weight/day were particularly effective in all organs and were well tolerated. This efficacy occurred even though, after severe challenge, mice had reduced water intake, resulting in ingesting less than the desired dose, particularly initially after infection. This study shows, for the first time, efficacy of nikZ against disseminated coccidioidomycosis. Efficacy was shown after challenges producing different levels of severity of disease. This study also suggests the likely benefits of developing an extended release formulation supplying continuous systemic concentrations of nikZ.

Noninvasive Combined Diagnosis and Monitoring of Aspergillus and Pseudomonas Infections: Proof of Concept

In acutely ill patients, particularly in intensive care units or in mixed infections, time to a microbe-specific diagnosis is critical to a successful outcome of therapy. We report the application of evolving technologies involving mass spectrometry to diagnose and monitor a patient’s course. As proof of this concept, we studied five patients and used two rat models of mono-infection and coinfection. We report the noninvasive combined monitoring of Aspergillus fumigatus and Pseudomonas aeruginosa infection. The invasive coinfection was detected by monitoring the fungal triacetylfusarinine C and ferricrocin siderophore levels and the bacterial metabolites pyoverdin E, pyochelin, and 2-heptyl-4-quinolone, studied in the urine, endotracheal aspirate, or breath condensate. The coinfection was monitored by mass spectrometry followed by isotopic data filtering. In the rat infection model, detection indicated 100-fold more siderophores in urine compared to sera, indicating the diagnostic potential of urine sampling. The tools utilized in our studies can now be examined in large clinical series, where we could expect the accuracy and speed of diagnosis to be competitive with conventional methods and provide advantages in unraveling the complexities of mixed infections.

Coinfection of disseminated cryptococcosis and BK Virus, a casualty of missed diagnosis during the COVID-19 Pandemic: A case report and review of the literature

Background and Purpose

The COVID-19 pandemic resulted in an overload of health services and healthcare professionals. The result is a setback in health promotion and prevention, delays in diagnosis, and deaths from other diseases that are currently receiving inadequate attention. This article illustrates the risk of this negligence.

Case report

This study aimed to report a case of coinfection of disseminated cryptococcosis and BK virus in a patient without a previous diagnosis of human immunodeficiency virus infection and COVID-19 negative in the context of the COVID-19 pandemic. Despite receiving antifungal therapy, the patient died.

Conclusion

This fatal case is a warning regarding delay of diagnosis and neglect of other serious illnesses owing to the current pandemic, including fungal diseases and neglected diagnoses.

CATastrophe: response to the challenges of zoonotic sporotrichosis in southern Brazil

BACKGROUND

In Brazil, zoonotic sporotrichosis became a national public health problem, with thousands of cases in the last decade in several regions of the country. In this context, health education activities are critical, especially in promoting early diagnosis and access to proper health care in sporotrichosis hyperendemic areas. Therefore, we report the implementation of a public specialized reference service (SRS) for diagnosis and treatment of sporotrichosis in southern Brazil We evaluated the impact of the SRS on diagnostic confirmation and speed of diagnosis.

METHODS

The SRS was implemented in Rio Grande city. We implemented a public service to promote the correct diagnosis, treatment and follow-up of human sporotrichosis cases. To study the impact of implementing SRS, the annual number of cases, and the period between the appearance of lesions until diagnosis were compared, using prior data and that post-implementation.

RESULTS

The implementation of the SRS directly benefited almost 50 patients in only four years, with the collaboration of almost 50% of the local health groups, together with an increase of more than 200% in diagnosis confirmation and speed of diagnosis, showing the reach, impact and importance of the SRS.

CONCLUSION

The impact on the individual and collective health of the local population highlights the value of this public health approach in facing the epidemiological threat of zoonotic sporotrichosis.

Severe Posaconazole-Induced Glucocorticoid Deficiency with Concurrent Pseudohyperaldosteronism: An Unfortunate Two-for-One Special

A 56-year-old Hispanic man with a history of disseminated coccidioidomycosis was diagnosed with persistent glucocorticoid insufficiency and pseudohyperaldosteronism secondary to posaconazole toxicity. This case was notable for unexpected laboratory findings of both pseudohyperaldosteronism and severe glucocorticoid deficiency due to posaconazole’s mechanism of action on the adrenal steroid synthesis pathway. Transitioning to fluconazole and starting hydrocortisone resolved the hypokalemia but not his glucocorticoid deficiency. This case highlights the importance of recognizing iatrogenic glucocorticoid deficiency with azole antifungal agents and potential long term sequalae.

Molecular epidemiology of aspergillosis in Magellanic penguins and susceptibility patterns of clinical isolates

Aspergillus section Fumigati is reported in up to 99% of aspergillosis cases in penguins. So far, no data regarding molecular epidemiology and azole resistance are available for A. fumigatus isolates collected from Magellanic penguins. The aim of this work was to perform molecular identification of Aspergillus section Fumigati at species level, to genotype those isolates using microsatellite markers, to evaluate the in vitro susceptibility patterns of A. fumigatus sensu stricto, and to characterize the cyp51A gene in clinical A. fumigatus strains isolated from Magellanic penguins with proven aspergillosis. All 34 isolates included in the study were identified as A. fumigatus sensu stricto. Analyzing the genetic diversity of the isolates of A. fumigatus sensu stricto, we identified two possible outbreaks in the rehabilitation center and we also observed the maintenance of clonal strains through the years. One A. fumigatus sensu stricto isolate was resistant to posaconazole, but the mutations found in the cyp51A gene of this isolate have not been described as conferring phenotypic resistance, suggesting that other mechanisms of resistance could be involved in the resistance of this isolate. With this study we were able to understand the molecular diversity of Aspergillus fumigatus isolates collected from Magellanic penguins, to characterize them and to associate them with the described global population of Aspergillus fumigatus.

Live imaging and quantitative analysis of Aspergillus fumigatus growth and morphology during inter-microbial interaction with Pseudomonas aeruginosa

Pseudomonas aeruginosa (PA) and Aspergillus fumigatus (AF) chronically colonize the airways of patients with cystic fibrosis or chronic immunosuppression and mutually affect each other’s pathogenesis. Here, we evaluated IncuCyte time-lapse imaging and NeuroTrack^TM (NT) analysis (Wurster et al., 2019, mBio) as a toolbox to study mycelial expansion and morphogenesis of AF during interaction with PA. Co-incubation of AF with supernatant filtrates of wild-type (WT) PA strains strongly inhibited hyphal growth and branching. Consonant with prior metabolic studies, pyoverdine-deficient PA mutants had significantly attenuated inhibitory capacity. Accordingly, purified PA products pyoverdine and pyocyanin suppressed mycelial expansion of AF in a concentration-dependent way. Using fluorescence-guided tracking of GFP-AF293 mycelia during co-culture with live WT PA cells, we found significant inoculum-dependent mycelial growth inhibition and robust precision of the NT algorithm. Collectively, our experiments position IncuCyte NT as an efficient platform for longitudinal analysis of fungal growth and morphogenesis during bacterial co-infection.

Efficacy of nikkomycin Z in murine CNS coccidioidomycosis: modelling sustained-release dosing

OBJECTIVES

Meningitis is the most feared coccidioidomycosis complication. Nikkomycin Z (nikZ) is a chitin synthase inhibitor. A concern is short half-life, necessitating multiple dose/day regimens. We simulated extended release, providing nikZ in drinking water. Extended release would enhance convenience, and adherence, for patients.

METHODS

Coccidioides posadasii was injected intracerebrally into mice. Twelve day treatments began on Day 3. Fluconazole was given 100 mg/kg once daily (gavage); designed doses of nikZ 30, 100 or 300 mg/kg/day in drinking water. On Day 30 post-treatment, survivors were euthanized, brain cfu quantitated and cfu in other organs assessed.

RESULTS

nikZ was stable in drinking water. Survival was 11%, 50%, 70%, 90% and 100% in untreated controls, fluconazole and nikZ 30, 100 and 300 mg/kg/day, respectively ; nikZ 300 mg/kg/day was superior (P ≤ 0.01) to fluconazole. Brains were sterilized in 0%, 20%, 86%, 89% and 80% of mice, respectively; nikZ 100 or 300 mg/kg/day was superior (P ≤ 0.01) to fluconazole. Clearance of infection in other organs was similar. All decreased drinking after infection, causing nikZ mice to ingest less than the desired dose in early therapy; despite this, they recovered sufficiently to resume pre-infection drinking and designed drug intakes. Thus, when sickest, even less than the designed dose was sufficient to enable recovery.

CONCLUSIONS

This efficacy supports the development of sustained-release nikZ. Decreased intake wouldn't be a factor in humans, receiving drug via extended-release pill or continuous IV infusion. In prior studies (twice daily nikZ) of murine coccidioidal meningitis, results were inferior, suggesting sustained release may provide both convenience and superior outcomes.

In vitro anti-Cryptococcus activity of diphenyl diselenide alone and in combination with amphotericin B and fluconazole

Cryptococcus is an encapsulated yeast that causes fungal meningitis, most commonly in HIV patients, with high mortality rates. Thus, the study of new treatment options is relevant. Antifungal activity of organoselenium compounds attributed to their pro-oxidative effect in fungal cells has been shown given that few data regarding its anti-Cryptococcus activity are available, this in vitro study was conducted with 40 clinical isolates of Cryptococcus neoformans. Diphenyl diselenide (DD) alone, and its interaction with amphotericin B or fluconazole, was tested by microdilution and checkerboard assays. All Cryptococcus neoformans were inhibited by DD in concentrations ≤ 32 μg/mL, and fungicidal concentrations were ≤ 64 μg/mL. Advantageous interaction between fluconazole occurred in 40% of the isolates, respectively. This study contributes with data of DD alone and in combination with classical drugs of choice for cryptococcosis treatment. Further studies focused on DD antifungal mechanism of action, and in vivo experiments are necessary.

Synergism of Nikkomycin Z in Combination with Diphenyl Diselenide Against Sporothrix spp

We evaluated the in vitro activity of nikkomycin Z (NikZ) in combination with diphenyl diselenide (PhSe)₂, two compounds previously shown to have anti-Sporothrix spp. activity. Eighteen isolates of Sporothrix spp. were tested in checkerboard assays. Synergism for inhibition and killing Sporothrix spp. occurred in 100% and 89% of the isolates, respectively. The anti-Sporothrix spp. activity of this combination provides a rationale for in vivo studies to evaluate the application of both compounds in sporotrichosis treatment.

The Pseudomonas aeruginosa product pyochelin interferes with Trypanosoma cruzi infection and multiplication in vitro

BACKGROUND

Bacteria are sources of numerous molecules used in treatment of infectious diseases. We investigated effects of molecules produced by 26 Pseudomonas aeruginosa strains against infection of mammalian cell cultures with Trypanosoma cruzi, the aetiological agent of Chagas disease.

METHODS

Vero cells were infected with T. cruzi in the presence of wild-type P. aeruginosa supernatants or supernatants of mutants with defects in the production of various virulence, quorum sensing and iron acquisition factors. Quantification of T. cruzi infection (percentage of infected cells) and multiplication (number of amastigotes per infected cell) was performed and cell viability was determined.

RESULTS

Wild-type P. aeruginosa products negatively affected T. cruzi infection and multiplication in a dose-dependent manner, without evident toxicity for mammalian cells. PvdD/pchE mutation (loss of the P. aeruginosa siderophores pyoverdine and pyochelin) had the greatest impact on anti-T. cruzi activity. Negative effects on T. cruzi infection by pure pyochelin, but not pyoverdine, or other P. aeruginosa exoproducts studied, were quantitatively similar to the effects of benznidazole, the current standard therapy against T. cruzi.

CONCLUSIONS

The P. aeruginosa product pyochelin showed promising activity against T. cruzi and might become a new lead molecule for therapy development.

Aspergillosis in albatrosses

Aspergillosis is a respiratory fungal disease of importance in captive marine birds. The aim of this study was to describe the occurrence of aspergillosis in Thalassarche melanophris during rehabilitation events and to identify the etiological agent. All the albatrosses that were received for rehabilitation and died within a 2-year period were included in the study. The proportionate mortality rate caused by aspergillosis was 21.4% (3/14). One of the etiological agents was Aspergillus flavus/oryzae lineage, and the other was A. fumigatus sensu stricto. Our study suggests that aspergillosis can act as a limiting factor in the rehabilitation of albatrosses.

Efficacy and Associated Drug Exposures of Isavuconazole and Fluconazole in an Experimental Model of Coccidioidomycosis

Coccidioides spp. are important pathogens in regions where they are endemic, and new treatment options are needed. Here, isavuconazonium sulfate (ISAVUSULF) and fluconazole (FLU) were evaluated in experimental disseminated coccidioidomycosis to characterize drug exposures associated with efficacy. Broth macrodilution was performed on Coccidioides isolates to measure minimal effective concentrations (MEC) and minimal fungicidal concentrations (MFC). Mice were inoculated with Coccidioides posadasii (Silveira strain). Treatment started 4 days postinoculation. In model 1, mice were treated for 19 days, followed by 30 days of off-therapy observation, measuring survival through day 49 and residual fungal burden. Treatments included ISAVUSULF (prodrug; 186, 279, or 372 mg/kg twice daily), FLU (20 or 100 mg/kg once daily), and no treatment. Model 2 included 7-day treatment with ISAVUSULF (prodrug; 74.4, 111.6, or 148.8 mg/kg twice daily), FLU (20 or 100 mg/kg once daily), and no treatment. Serial plasma and tissues samples were obtained for pharmacokinetics (PK) and fungal burden measurement, respectively. Fifty percent minimal effective concentration (MEC50) values were 0.39 mg/liter (isavuconazole [ISAV]) and 12.5 mg/liter (FLU). Treatment with ISAVUSULF186 or with either FLU dose resulted in higher survival compared to that in the untreated group. Treatment with ISAVUSULF186 or ISAVUSULF279 twice daily or FLU100 reduced fungal burden in all organs (model 1). In model 2, a >1 log10 CFU/organ reduction was demonstrated, with ISAV area under the concentration-time curve (AUC) values achieved with 111.6 mg/kg twice daily (56.8 mg · h/liter) in the spleen and liver. FLU AUC values of 100 and 500 mg·h/liter for 20 and 100 mg/kg doses, respectively, resulted in a >1 log10 CFU/organ mean reduction in all organs. ISAVUSULF and FLU improved survival and reduced fungal burden. Increasing plasma drug exposures resulted in decreases in fungal burden.

Concurrent Pseudohyperaldosteronism and Primary Glucocorticoid Deficiency From Posaconazole

Background: Posaconazole can cause pseudohyperaldosteronism via inhibition of 11-beta hydroxylase and 11-beta-hydroxysteroid dehydrogenase type 2 (1). The accumulation of 11-deoxycorticosterone and increased cortisol-to-cortisone ratio in the kidney causes apparent mineralocorticoid excess. The effect of posaconazole on the glucocorticoid axis is less established.

Clinical Case: A 56-year-old Hispanic man with a history of chronic septic arthritis of the left ankle from Coccidioides presented with 3 months of malaise, nausea, weight loss of 30 pounds, and recurrent hypokalemia. He was recently switched from long-term fluconazole therapy to posaconazole around the time his symptoms began. His initial labs at our hospital were notable for low potassium (2.9 mmol/L, nl 3.5–5.5 mmol/L) and a random cortisol of 5.8 mcg/dL (nl ≥2.0 mcg/dL). A Cosyntropin stimulation test revealed elevated ACTH (168 pg/mL, nl 7.2–63.3 pg/mL) with minimal rise of cortisol from 4.6 to 7.2 mcg/dL at 1 hour after Cosyntropin administration (nl ≥18 mcg/dL at 1-hour post-Cosyntropin). His plasma renin activity was below detection (<0.6 ng/ml/h, nl 0.6–3.0 ng/mL/h), consistent with renin suppression from apparent mineralocorticoid excess. Hydrocortisone for glucocorticoid deficiency was started. A posaconazole determination indicated elevation (5240 ng/mL, usual therapeutic range ≥1000 ng/mL). His posaconazole was stopped, and he was switched back to fluconazole. Three months later, his symptoms were improved with regain of lost weight. Repeat Cosyntropin stimulation test showed ongoing primary glucocorticoid deficiency (ACTH 123 pg/mL, cortisol 4.1 mcg/dL at 1-hour post-Cosyntropin) but normal levels of plasma renin activity (1.2 ng/mL/h), aldosterone (8.6 ng/dL, nl ≤21 ng/dL), and potassium. Quantiferon TB and 21-hydroxylase antibody tests were negative. Hydrocortisone has been continued with plans to repeat Cosyntropin testing in 3 months to reassess.

Conclusion: Pseudohyperaldosteronism with glucocorticoid deficiency requiring hydrocortisone treatment has thus far not been reported with posaconazole. Our case shows that posaconazole may lead to true primary glucocorticoid deficiency that can persist after discontinuation of posaconazole and reversal of pseudohyperaldosteronism.

Reference: (1) Sanchez-Niño MD, Ortiz A. Unravelling drug-induced hypertension: Molecular mechanisms of aldosterone-independent mineralocorticoid receptor activation by posaconazole. Clin Kidney J 2018;11(5):688–90.

Molecular Modifications of the Pseudomonas Quinolone Signal in the Intermicrobial Competition with Aspergillus

The Pseudomonas quinolone signal (PQS) is an important quorum-sensing molecule for Pseudomonas aeruginosa that regulates virulence factors, chelates iron, and is an important factor in interactions with eukaryotes, including fungi and mammalian hosts. It was previously shown to inhibit or boost Aspergillus, depending on the milieu iron concentration. We studied several molecular modifications of the PQS molecule, and their effects on Aspergillus biofilm metabolism and growth in vitro, and the effects of iron supplementation. We found that most molecules inhibited Aspergillus at concentrations similar to that of PQS, but with relatively flat dose-responses, and all were less potent than PQS. The inhibition was reversible by iron, suggesting interference with fungal iron metabolism. Stimulation of Aspergillus was not noted. We conclude that the critical Aspergillus-inhibiting moeities of the PQS molecule were partially, but not completely, interfered with by molecular modifications at several sites on the PQS molecule. The mechanism, as with PQS, appears to relate to fungal iron metabolism.

Pseudomonas aeruginosa Virulence Factors Support Voriconazole Effects on Aspergillus fumigatus

Pseudomonas aeruginosa and Aspergillus fumigatus are pathogens that are associated with deterioration of lung function, e.g., in persons with cystic fibrosis (CF). There is evidence that co-infections with these pathogens cause airway inflammation and aggravate pathology in CF lungs. Intermicrobial competition of P. aeruginosa and A. fumigatus has been described, but it is unknown how anti-fungal therapy is affected. The anti-fungal azole voriconazole (VCZ), supernatants of P. aeruginosa laboratory isolates PA14 or PAO1, or clinical isolate Pa10 independently inhibited biofilm metabolism of A. fumigatus isolates 10AF and AF13073. When VCZ and supernatants were combined at their IC₅₀s, synergistic effects on A. fumigatus were found. Synergistic effects were no longer observed when P. aeruginosa supernatants were prepared in the presence of iron, or when P. aeruginosa mutants were lacking the ability to produce pyoverdine and pyochelin. Combination of pure P. aeruginosa products pyoverdine, pyochelin, and pyocyanin with VCZ showed synergistic anti-fungal effects. Combining VCZ with P. aeruginosa supernatants also improved its MIC and MFC against planktonic A. fumigatus. In summary, in the case of P. aeruginosa–A. fumigatus co-infections, it appeared that the P. aeruginosa co-infection facilitated therapy of the Aspergillus; lower concentrations of VCZ might be sufficient to control fungal growth.

Virus Infection of Aspergillus fumigatus Compromises the Fungus in Intermicrobial Competition

Aspergillus and Pseudomonas compete in nature, and are the commonest bacterial and fungal pathogens in some clinical settings, such as the cystic fibrosis lung. Virus infections of fungi occur naturally. Effects on fungal physiology need delineation. A common reference Aspergillus fumigatus strain, long studied in two (of many) laboratories, was found infected with the AfuPmV-1 virus. One isolate was cured of virus, producing a virus-free strain. Virus from the infected strain was purified and used to re-infect three subcultures of the virus-free fungus, producing six fungal strains, otherwise isogenic. They were studied in intermicrobial competition with Pseudomonasaeruginosa. Pseudomonas culture filtrates inhibited forming or preformed Aspergillus biofilm from infected strains to a greater extent, also seen when Pseudomonas volatiles were assayed on Aspergillus. Purified iron-chelating Pseudomonas molecules, known inhibitors of Aspergillus biofilm, reproduced these differences. Iron, a stimulus of Aspergillus, enhanced the virus-free fungus, compared to infected. All infected fungal strains behaved similarly in assays. We show an important consequence of virus infection, a weakening in intermicrobial competition. Viral infection may affect the outcome of bacterial–fungal competition in nature and patients. We suggest that this occurs via alteration in fungal stress responses, the mechanism best delineated here is a result of virus-induced altered Aspergillus iron metabolism.

Gloeostereum cimri, a novel shelf fungus isolated from a human pulmonary cyst

Filamentous basidiomycetes are uncommon agents of human diseases, despite their ubiquitous presence in the environment. We present a case of symptomatic pulmonary infection in a 38-year-old male with cough and fever; a thin-walled cyst in the posterior left upper pulmonary lobe was revealed by radiography. A non-sporulating fungus was isolated from sputum and biopsy material from the cyst. ITS and LSU sequences placed the fungus phylogenetically in Agaricales, family Cyphellaceae, and identified it as a member of shelf fungi in Gloeostereum, but without identity to any known species. The new species is described as Gloeostereum cimri. The clinical strain showed high MIC to voriconazole (>8 µg/ml) but had low MIC to amphotericin B (0.5 µg/ml).

Ebselen and diphenyl diselenide against fungal pathogens: A systematic review

Fungal infections are one of the most prevalent diseases in the world and there is a lack of new antifungal drug development for these diseases. We conducted a systematic review of the literature regarding the in vitro antifungal activity of the organoselenium compounds ebselen (Eb) and diphenyl diselenide [(PhSe)2]. A systematic review was carried out based on the search for articles with data concerning Minimal Inhibitory Concentration (MIC) values, indexed in international databases and published until August 2020. A total of 2337 articles were found, and, according to the inclusion and exclusion criteria used, 22 articles were included in the study. Inhibitory activity against 96% (200/208) and 95% (312/328) of the pathogenic fungi tested was described for Eb and [(PhSe)2], respectively. Including in these 536 fungal isolates tested, organoselenium activity was highlighted against Candida spp., Cryptococcus ssp., Trichosporon spp., Aspergillus spp., Fusarium spp., Pythium spp., and Sporothrix spp., with MIC values lower than 64 μg/mL. In conclusion, Eb and [(PhSe)2] have a broad spectrum of in vitro inhibitory antifungal activity. These data added with other pharmacological properties of these organoselenium compounds suggest that both compounds are potential future antifungal drugs. Whether MICs toward the upper end of the ranges described here are compatible with efficacious therapy, and whether they may achieve such end as a result of the favorable non-antimicrobial effects of selenium on the host, requires more in vivo testing.

COVID-19-Associated Histoplasmosis in an AIDS Patient

Most reports associating fungal infections with COVID-19 have been cases of invasive aspergillosis. Here, we report a case of severe histoplasmosis and COVID-19 infections in an HIV patient in Rio Grande, Southern Brazil. Histoplasmosis must be included as a diagnostic possibility in opportunistic fungal co-infections in COVID-19 patients with AIDS, mainly in endemic areas.

Cryptococcosis in HIV-AIDS patients from Southern Brazil: Still a major problem

INTRODUCTION

Cryptococcus neoformans is an opportunistic pathogen that causes ∼15% mortality in AIDS patients. Rio Grande City, Rio Grande do Sul (RS), Brazil, has the highest national rate of HIV/AIDS, considering cities with population more than 100,000 habitants.

OBJECTIVE

We aimed to evaluate the clinical and epidemiological profile of cryptococcosis in a reference service for HIV-AIDS patients in the South region of Brazil, over seven years. Material and methods A retrospective study was performed including all cryptococcosis cases diagnosed at the University Hospital, Federal University of Rio Grande (UH-FURG) between January 2010 and December 2016.

RESULTS

Seventy cases of cryptococcosis were diagnosis from 2010 to 2016 in the UH-FURG in the seven years of the study. These numbers were responsible for 2.1% to 8.1% of the hospitalizations/year for HIV patients. All were caused by C. neoformans infection (95% C. neoformans var. grubii VNI and 5% C. neoformans var. grubii VNII). Neurocryptococcosis was the major clinical manifestation and cryptococcosis was the HIV- defining condition in 40% of patients. The period of hospitalization was an average of 39.3 days (SD=31.3), and more than half of patients (53%; 37/70) died after a mean of 82 days.

DISCUSSION

The present study showed the importance of cryptococcosis as an AIDS-defining disease in HIV-AIDS patients in a tertiary hospital from Southern Brazil. More investment is necessary to reduce the impact of this opportunistic mycosis in HIV-AIDS patients from southern Brazil.

Revision and Update of the Consensus Definitions of Invasive Fungal Disease From the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium

BACKGROUND

Invasive fungal diseases (IFDs) remain important causes of morbidity and mortality. The consensus definitions of the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group have been of immense value to researchers who conduct clinical trials of antifungals, assess diagnostic tests, and undertake epidemiologic studies. However, their utility has not extended beyond patients with cancer or recipients of stem cell or solid organ transplants. With newer diagnostic techniques available, it was clear that an update of these definitions was essential.

METHODS

To achieve this, 10 working groups looked closely at imaging, laboratory diagnosis, and special populations at risk of IFD. A final version of the manuscript was agreed upon after the groups' findings were presented at a scientific symposium and after a 3-month period for public comment. There were several rounds of discussion before a final version of the manuscript was approved.

RESULTS

There is no change in the classifications of "proven," "probable," and "possible" IFD, although the definition of "probable" has been expanded and the scope of the category "possible" has been diminished. The category of proven IFD can apply to any patient, regardless of whether the patient is immunocompromised. The probable and possible categories are proposed for immunocompromised patients only, except for endemic mycoses.

CONCLUSIONS

These updated definitions of IFDs should prove applicable in clinical, diagnostic, and epidemiologic research of a broader range of patients at high-risk.

Diphenyl diselenide and its interaction with antifungals against Aspergillus spp

Given the few antifungal classes available to treat aspergillosis, this study aimed to evaluate the in vitro antifungal activity of diphenyl diselenide (PhSe)2 alone and in combination with classical antifungals against Aspergillus spp., and its in vivo activity in a systemic experimental aspergillosis model. We performed in vitro broth microdilution assay of (PhSe)2 against 32 Aspergillus isolates; and a checkboard assay to test the interaction of this compound with itraconazole (ITC), voriconazole (VRC), amphotericin B (AMB), and caspofungin (CAS), against nine Aspergillus isolates. An experimental model of invasive aspergillosis in mice was studied, and survival curves were compared between an untreated group and groups treated with 100 mg/kg ITC, or (PhSe)2 in different dosages (10 mg/kg, 50 mg/kg and 100 mg/kg). All Aspergillus non-fumigatus and 50% of A. fumigatus were inhibited by (PhSe)2 in concentrations ≤ 64 µg/ml, with significant differences in MICs between the sections. Synergism or additive effect in the in vitro (PhSe)2 interaction with VRC and CAS was observed against the majority of isolates, and with ITC against the non-fumigatus strains. In addition to the inhibitory interaction, (PhSe)2 was able to add a fungicidal effect to CAS. Survival curves from the systemic experimental aspergillosis model demonstrated that the inoculum caused an acute and lethal infection in mice, and no treatment applied significantly prolonged survival over that of the control group. The results highlight the promising activity of (PhSe)2 against Aspergillus species, but more in vivo studies are needed to determine its potential applicability in aspergillosis treatment.

LAY SUMMARY

The activity of diphenyl diselenide (PhSe)2 alone and in combination with itraconazole, voriconazole, and caspofungin, is described against three of the most pathogenic Aspergillus sections. (PhSe)2 may prove useful in therapy of infection in future; further study is required.