Proceedings of the Second International Meeting on Endemic Mycoses of the Americas (IMEMA), and First International Symposium on Implantation Mycoses (ISIM).

The Second International Meeting on Endemic Mycoses of the Americas (IMEMA) and the First International Symposium on Implantation Mycoses (ISIM) took place in Santiago del Estero, Argentina during September 25-27th, 2023. The conference provided a platform for researchers, clinicians, and experts to discuss the latest developments in the field of endemic and implantation mycoses. Topics included epidemiology, diagnostic advances, treatment strategies, and the impact of environmental factors in the spread of these fungal diseases. IMEMA and ISIM contributed to the regional discourse on the mycoses, emphasizing the importance of international cooperation in addressing these public health challenges.

IMEMA/ISIM, held in Santiago del Estero, Argentina, convened experts to discuss endemic and implantation mycoses, covering topics such as epidemiology, diagnostics, treatment, and advocacy. The event highlighted ongoing efforts in combating these diseases.

Carbon nanoparticle-based lateral flow assay for the detection of specific double-tagged DNA amplicons of Paracoccidioides spp.

To overcome the limitations of current methods for diagnosing paracoccidioidomycosis (PCM), it is critical to develop novel diagnostic strategies that can be implemented in low-resource settings and dramatically improve turnaround times. This study focused on the development of a portable molecular test to screen for Paracoccidioides spp. The proposed approach integrated double-tagging polymerase chain reaction (PCR) and a paper-based lateral flow assay (LFA) for readout, using carbon nanoparticles as a signal generation system. Primers tagged with biotin and digoxigenin were employed to conduct the double-tagging PCR, which can be conveniently carried out on portable thermocyclers. This method can generate billions of tagged DNA copies from a single target molecule, which can be rapidly detected by the LFA platform, providing results within minutes. Avidin-modified carbon nanoparticles served as a signal generation system, enabling detection in the immunochromatographic assay. The LFA demonstrated the capability to detect double-tagged amplicons as low as 0.21 ng or 0.10 ng, depending on whether the results were assessed visually or with a smartphone equipped with an image processor. These findings suggest that the proposed approach holds great promise as a point-of-care diagnostic tool for the early and accurate detection of PCM in low-resource settings. The diagnostic test is rapid and inexpensive, requires minimal handling and can be easily introduced into the general practitioner's armoury for ambulatory screening of infection. This innovative approach has the potential to make a substantial contribution to PCM diagnosis, ultimately reducing morbidity and mortality associated with this disease.

Epidemiology of coccidioidomycosis in Argentina, an update.

The National Reference Laboratory in Clinical Mycology of Argentina conducted a retrospective review of human coccidioidomycosis cases diagnosed by the National Mycology Laboratory Network of Argentina between 2010 and 2022 to determine the burden of the disease in the country. A total of 100 human coccidioidomycosis cases were documented, with a higher prevalence in male patients (male-to-female ratio of 1.9:1), with a median age of 41 years. Comparing the number of cases between two 10-year periods (2000-2009 and 2010-2019), the increase was 36.51% (from 63 to 86 cases). Among the 100 recorded cases, 79 tested positive using the double immunodiffusion test. Spherules were observed in 19 cases through histopathology or direct microscopic examination and the fungus was isolated in 39 cases. Thirty-six isolates were identified as Coccidioides posadasii through partial sequencing of the Ag2/PRA gene. Catamarca province had the highest number of cases, comprising 64% of the total, with an incidence rate above 1.0-2.5/100,000 inhabitants until 2018. However, there has been a recent downward trend in the region from 2018 to 2022. It is concerning that more than half of diagnosed cases were chronic pulmonary or disseminated forms, indicating a lack of early disease detection. To rectify this issue, it is imperative to conduct targeted training programs for healthcare personnel and enhance public awareness within the endemic area. This will contribute to a better understanding of the true burden of coccidioidomycosis and enable the implementation of appropriate sanitary control measures.

Identification of Virulence Factors in Isolates of Candida haemulonii, Candida albicans and Clavispora lusitaniae with Low Susceptibility and Resistance to Fluconazole and Amphotericin B.

Emerging life-threatening multidrug-resistant (MDR) species such as the C. haemulonii species complex, Clavispora lusitaniae (sin. C. lusitaniae), and other Candida species are considered as an increasing risk for human health in the near future. (1) Background: Many studies have emphasized that the increase in drug resistance can be associated with several virulence factors in Candida and its knowledge is also essential in developing new antifungal strategies. (2) Methods: Hydrophobicity, adherence, biofilm formation, lipase activity, resistance to osmotic stress, and virulence 'in vivo' on G. mellonella larvae were studied in isolates of C. haemulonii, C. albicans, and C. lusitaniae with low susceptibility and resistance to fluconazole and amphotericin B. (3) Results: Intra- and interspecies variability were observed. C. haemulonii showed high hydrophobicity and the ability to adhere to and form biofilm. C. lusitaniae was less hydrophobic, was biofilm-formation-strain-dependent, and did not show lipase activity. Larvae inoculated with C. albicans isolates displayed significantly higher mortality rates than those infected with C. haemulonii and C. lusitaniae. (4) Conclusions: The ability to adhere to and form biofilms associated with their hydrophobic capacity, to adapt to stress, and to infect within an in vivo model, observed in these non-wild-type Candida and Clavispora isolates, shows their marked virulence features. Since factors that define virulence are related to the development of the resistance of these fungi to the few antifungals available for clinical use, differences in the physiology of these cells must be considered to develop new antifungal therapies.

Part 2: Understanding the role of Malassezia spp. in skin disorders: pathogenesis of Malassezia associated skin infections.

INTRODUCTION: Malassezia is a major component of the skin microbiome, a lipophilic symbiotic organism of the mammalian skin, which can switch to opportunistic pathogens triggering multiple dermatological disorders in humans and animals. This phenomenon is favored by endogenous and exogenous host predisposing factors, which may switch Malassezia from a commensal to a pathogenic phenotype. AREA COVERED: This review summarizes and discusses the most recent literature on the pathogenesis of Malassezia yeasts, which ultimately results in skin disorders with different clinical presentation. A literature search of Malassezia pathogenesis was performed via PubMed and Google scholar (up to May 2023), using the following keywords: Pathogenesis and Malassezia;host risk factors and Malassezia, Malassezia and skin disorders; Malassezia and virulence factors: Malassezia and metabolite production; Immunology and Malassezia. EXPERT OPINION: Malassezia yeasts can maintain skin homeostasis being part of the cutaneous mycobiota; however, when the environmental or host conditions change, these yeasts are endowed with a remarkable plasticity and adaptation by modifying their metabolism and thus contributing to the appearance or aggravation of human and animal skin disorders.

Part 1: Understanding the role of Malassezia spp. in skin disorders: Malassezia yeasts as commensal or pathogenic organisms of human and animal skin.

INTRODUCTION: Malassezia spp. are a group of lipid-dependent basidiomycetes yeasts acting as commensal organisms of the human and animal skin. However, under some not well-defined circumstances, these yeasts may switch to opportunistic pathogens triggering a number of skin disorders with different clinical presentations. The genus comprises of 18 lipid-dependent species with a variable distribution in the hosts and pathologies thus suggesting a host- and microbe-specific interactions. AREA COVERED: This review highlighted and discussed the most recent literature regarding the genus Malassezia as a commensal or pathogenic organisms highlighting Malassezia-associated skin disorders in humans and animals and their antifungal susceptibility profile. A literature search of Malassezia associated skin disorders was performed via PubMed and Google scholar (up to May 2023), using the different keywords mainly associated with Malassezia skin disorders and Malassezia antifungal resistance. EXPERT OPINION: Malassezia yeasts are part of the skin mycobiota and their life cycle is strictly associated with the environment in which they live. The biochemical, physiological, or immunological condition of the host skin selects Malassezia spp. or genotypes able to survive in a specific environment by changing their metabolisms, thus producing virulence factors or metabolites which can cause skin disorders with different clinical presentations.

Sporotrichosis in Argentina: clinical and epidemiological analysis / Esporotricosis en Argentina: análisis clínico y epidemiológico

Introduction: Sporotrichosis is an implantation mycosis caused by Sporothrix spp. It is distributed worldwide and can be found in vegetation and soil. The most frequent route of infection is by trauma with elements contaminated with fungal propagules. Since domestic cats are the most affected animals and can transmit this infection to humans, sporotrichosis is considered a zoonosis. Clinical presentations include nodular lymphangitis, fixed cutaneous, pulmonary (rare), and disseminated (exceptional). Objectives: To analyze the epidemiology of sporotrichosis in Argentina during 2010 and 2022. To describe the clinical presentation, diagnostic methods, and treatment of cases diagnosed during this period. To know the circulating genotypes and to observe possible associations with the geographic location where the infection was acquired. Materials and methods: Analytical, retrospective, and observational study. We analyzed the medical records of patients with sporotrichosis from 12 health institutions in Argentina, between 2010 and 2022. Results: We present 54 cases in which the most frequent clinical form was nodular lymphangitis, and the treatment of choice was itraconazole. Conventional diagnosis was made in all cases. Culture of clinical samples was more sensitive than direct examination because it allowed the isolation of Sporothrix spp. in all 54 cases. Molecular identification was performed in 22 cases, with Sporothrix schenkii sensu stricto being the most frequently isolated species. Conclusions: This study allowed to know the epidemiology of this mycosis in Argentina, as well as the availability of diagnostic methods and the treatment of choice.

Introducción: La esporotricosis es una micosis de implantación causada por Sporothrix spp. Este se encuentra distribuido mundialmente y se puede encontrar en la vegetación y en el suelo. La ruta más frecuente de adquisición de la infección es por traumatismos con elementos contaminados con propágulos del hongo. Los gatos domésticos son los animales más afectados y pueden transmitirla a los humanos, por lo que es considerada una zoonosis. Las formas clínicas incluyen: la linfangítica nodular, la cutánea fija, la pulmonar (poco habitual) y la diseminada (excepcional). Objetivo: Analizar la epidemiología de la esporotricosis en Argentina entre los años 2010 y 2022. Describir la presentación clínica, los métodos de diagnóstico y el tratamiento de los casos diagnosticados en este período. Conocer los genotipos circulantes y observar su relación con el lugar geográfico de adquisición de la infección. Materiales y métodos. Se llevó a cabo un estudio analítico, retrospectivo y observacional, en el que se analizaron las historias clínicas de los pacientes con esporotricosis de 12 instituciones de salud de Argentina, entre los años 2010 y 2022. Resultados: Se presentan 54 casos en los que la forma clínica más frecuente fue la linfangítica nodular y el tratamiento de elección fue el itraconazol. En todos los casos se realizó diagnóstico convencional. El cultivo de las muestras clínicas resultó más sensible que el examen directo, ya que permitió el desarrollo de Sporothrix spp. en los 54 casos. En 22 casos se hizo identificación molecular y Sporothrix schenkii sensu stricto fue la especie más frecuentemente aislada. Conclusiones: Este estudio permitió conocer la epidemiología de esta micosis en Argentina, así como la disponibilidad de métodos diagnósticos y el tratamiento de elección.

Esporotricosis en Argentina: análisis clínico y epidemiológico / Sporotrichosis in Argentina: clinical and epidemiological analysis

Introducción. La esporotricosis es una micosis de implantación causada por Sporothrix spp. Este se encuentra distribuido mundialmente y se puede encontrar en la vegetación y en el suelo. La ruta más frecuente de adquisición de la infección es por traumatismos con elementos contaminados con propágulos del hongo. Los gatos domésticos son los animales más afectados y pueden transmitirla a los humanos, por lo que es considerada una zoonosis. Las formas clínicas incluyen: la linfangítica nodular, la cutánea fija, la pulmonar (poco habitual) y la diseminada (excepcional). Objetivo. Analizar la epidemiología de la esporotricosis en Argentina entre los años 2010 y 2022. Describir la presentación clínica, los métodos de diagnóstico y el tratamiento de los casos diagnosticados en este período. Conocer los genotipos circulantes y observar su relación con el lugar geográfico de adquisición de la infección. Materiales y métodos. Se llevó a cabo un estudio analítico, retrospectivo y observacional, en el que se analizaron las historias clínicas de los pacientes con esporotricosis de 12 instituciones de salud de Argentina, entre los años 2010 y 2022. Resultados. Se presentan 54 casos en los que la forma clínica más frecuente fue la linfangítica nodular y el tratamiento de elección fue el itraconazol. En todos los casos se realizó diagnóstico convencional. El cultivo de las muestras clínicas resultó más sensible que el examen directo, ya que permitió el desarrollo de Sporothrix spp. en los 54 casos. En 22 casos se hizo identificación molecular y Sporothrix schenkii sensu stricto fue la especie más frecuentemente aislada. Conclusiones. Este estudio permitió conocer la epidemiología de esta micosis en Argentina, así como la disponibilidad de métodos diagnósticos y el tratamiento de elección.

Introduction. Sporotrichosis is an implantation mycosis caused by Sporothrix spp. It is distributed worldwide and can be found in vegetation and soil. The most frequent route of infection is by trauma with elements contaminated with fungal propagules. Since domestic cats are the most affected animals and can transmit this infection to humans, sporotrichosis is considered a zoonosis. Clinical presentations include nodular lymphangitis, fixed cutaneous, pulmonary (rare), and disseminated (exceptional). Objective. To analyze the epidemiology of sporotrichosis in Argentina during 2010 and 2022. To describe the clinical presentation, diagnostic methods, and treatment of cases diagnosed during this period. To know the circulating genotypes and to observe possible associations with the geographic location where the infection was acquired. Materials and methods. Analytical, retrospective, and observational study. We analyzed the medical records of patients with sporotrichosis from 12 health institutions in Argentina, between 2010 and 2022. Results. We present 54 cases in which the most frequent clinical form was nodular lymphangitis, and the treatment of choice was itraconazole. Conventional diagnosis was made in all cases. Culture of clinical samples was more sensitive than direct examination because it allowed the isolation of Sporothrix spp. in all 54 cases. Molecular identification was performed in 22 cases, with Sporothrix schenkii sensu stricto being the most frequently isolated species. Conclusions. This study allowed to know the epidemiology of this mycosis in Argentina, as well as the availability of diagnostic methods and the treatment of choice.

Clinical and Demographic Features of Paracoccidioidomycosis in Argentina: A Multicenter Study Analysis of 466 Cases.

Information on paracoccidioidomycosis (PCM) in Argentina is fragmented and has historically been based on estimates, supported only by a series of a few reported cases. Considering the lack of global information, a national multicentric study in order to carry out a more comprehensive analysis was warranted. We present a data analysis including demographic and clinical aspects of a historical series of 466 cases recorded over 10 years (2012-2021). Patients were aged from 1 to 89 years. The general male: female (M:F) ratio was 9.5:1 with significant variation according to the age group. Interestingly, the age range 21-30 shows an M:F ratio of 2:1. Most of the cases (86%) were registered in northeast Argentina (NEA), showing hyperendemic areas in Chaco province with more than 2 cases per 10,000 inhabitants. The chronic clinical form occurred in 85.6% of cases and the acute/subacute form occurred in 14.4% of cases, but most of these juvenile type cases occurred in northwestern Argentina (NWA). In NEA, the incidence of the chronic form was 90.6%; in NWA, the acute/subacute form exceeded 37%. Diagnosis by microscopy showed 96% positivity but antibody detection displays 17% of false negatives. Tuberculosis was the most frequent comorbidity, but a diverse spectrum of bacterial, fungal, viral, parasitic, and other non-infectious comorbidities was recorded. This national multicenter registry was launched in order to better understand the current status of PCM in Argentina and shows the two endemic zones with a highly diverse epidemiology.

Modulatory effect of Origanum vulgare essential oil and carvacrol on Malassezia spp. virulence factors.

Malassezia sympodialis and Malassezia furfur are recognized as an important part of the human and animals healthy skin microbiota, but also as an opportunistic fungus due to their association with a broad spectrum of skin and systemic infections. Human skin infections associated with Malassezia spp. are often chronic, recurrent, and topical or oral azole treatments are challenging with not always successful outcomes. A wide inter and intraspecies antifungal susceptibility variability that may suggest a combination of wild-type strains and resistant mutants was reported. The essential oils are complex hydrophobic mixtures of different compounds extracted from plants by distillation and have demonstrated antimicrobial activity. In this study, toxicity in the larvae model and the ability of Origanum vulgare essential oil (OVEO) and carvacrol to inhibit virulence factors such as hydrophobicity, adherence, and biofilm formation of M. sympodialis and M. furfur was evaluated. We have demonstrated the antifungal activity of OVEO and carvacrol against both species. Carvacrol was more active and less toxic than OVEO at low concentrations (< 1 mg/ml). Malassezia sympodialis showed a significant decrease in adherence and its ability to form biofilms when OVEO or carvacrol is present. Both Malassezia species showed reduced hydrophobicity in the presence of carvacrol. Further studies will have to be carried out to understand how these substances act, but the inhibition of some virulence factors could represent a new target to overcome the problem of drug resistance.

The work reports the research on the effect of the Origanum vulgare essential oil and carvacrol, against virulence factors such as hydrophobicity, adherence, and biofilm formation of two species of Malassezia. The inhibition of virulence factors could represent a new target to overcome the drug resistance reported.

Evaluación clínica y microbiológica usando tres técnicas de eliminación de tejido cariado / Avaliação clínica e microbiológica de três técnicas para eliminação do tecido cariado / Root fracture in the permanent maxillary central incisors: a case report of 10 years follow-up

Objetivo: Comparar, la efectividad clínica y microbiológica, entre las técnicas de eliminación tradicional y químico-mecánicas, para el tratamiento de lesiones cavitadas abiertas no penetrantes en dientes primarios en niños de 4 a 8 años, analizándose 57 dientes primarios. Grupo I: técnica tradicional (19 piezas), Grupo II: Brix (18 piezas), Grupo III: Papacarie (20 piezas). Evaluación clínica (necesidad de anestesiar y tiempo de ejecución) los datos fueron asentados en cada historia clínica. Antes y después del procedimiento operatorio, se tomaron muestras de la cavidad con microbrush estéril, transportándolas en tioglicolato para analizar cuantitativamente el total de bacterias presente por mililitro, utilizando cultivos de agar sangre (base Columbia). La información fue tabulada y analizada estadísticamente mediante Análisis de la Variancia, pruebas de Tukey y de Chi Cuadrado, estableciéndose como criterio de significancia p≤0.05. La diferencia significativa en la cantidad de bacterias entre el grupo I (41.22 ± 4.45) y los grupos II y III (65.96 ± 4.33, 83.45 ± 4.57), reveló que el grupo I fue menos efectivo. En los grupos II y III no se requirió la utilización de anestesia, siendo significativa la diferencia en los niños de edad preescolar (4 y 5 años). El tiempo de ejecución para cada técnica manifestó mayor rapidez en el grupo I (2.12 min ± 0.15) p˂0.0001. Las técnicas que utilizan algún agente químico permiten una mayor eliminación de bacterias durante la remoción de tejido cariado, sin recurrir a anestesia, por lo que pueden ser recomendadas como alternativa al tratamiento tradicional especialmente en niños pequeños.

Objetivo. Este estudo pretende comparar a eficácia clínica e microbiológica de três técnicas para a eliminação do tecido cariado, em crianças dos 4 aos 8 anos. Materiais e Método. Cinquenta e sete dentes decíduos foram analisados. Grupo I: técnica tradicional (19 dentes), Grupo II: Brix (18 dentes), Grupo III: Papacarie (20 dentes). Os dados para avaliação clínica (necessidade de anestesia e tempo de execução) foram registrados em cada anamnese. Antes e após o procedimento operatório, foram retiradas amostras da lesão cariosa com microbrush estéril, transportadas em tioglicolato para análise quantitativa do total de bactérias presentes por mililitro, utilizando culturas de ágar sangue (base Columbia). A informaçâo foi tabulada e analisada estatisticamente por meio do Analize da Varianza, testes de Tukey e do Qui-Quadrado, estabelecendo-se p≤0.05 como critério de significância. Resultados. A diferença na cantidade de bactérias entre o grupo I (41.22 ± 4.45), II e III (65.96 ± 4.33, 83.45 ± 4.57), revelou que o grupo I foi menos eficaz. Os grupos II e III não necessitaram do uso de anestesia, sendo a diferença significativa no grupo de pré-escolares (4 e 5 anos). O tempo de execução de cada técnica foi mais rápido no grupo I (2.12 min ± 0.15) p˂0.0001. Conclusão. As técnicas que utilizam algum agente químico permitem uma maior eliminação de bactérias durante a remoção do tecido cariado, sem recorrer à anestesia, podendo ser recomendadas como alternativa ao tratamento tradicional, especialmente em crianças pequenas.

Aim. This study pretends to compare the clinical and microbiological effectiveness of three techniques for the elimination of carious tissue in children aged 4 to 8 years old. Methods. Fifty-seven primary teeth were analyzed. Group I: traditional technique (19 teeth), Group II: Brix (18 teeth), Group III: Papacarie (20 teeth). The data for clinical evaluation (need for anesthesia and running time) were recorded in each case history. Before and after the operative procedure, samples were taken from the carious lesion with sterile micro brush, transported in thioglycollate to quantitatively analyze the total bacteria present per milliliter, using blood agar cultures (Columbia base). Information was tabulated and statistically analyzed using Analysis of Variance, Tukey's and Chi Square tests, establishing p≤0.05 as the criterion of significance. Results. The difference on number of bacteria between group I (41.22 ± 4.45), and groups II and III (65.96 ± 4.33, 83.45 ± 4.57), revealed that group I was less effective. Groups II and III did not require the use of anesthesia, the difference being significant in the group of pre-school children (4 and 5 years old). The execution time for each technique was faster in group I (2.12 min ± 0.15) p˂0.0001. Conclusions. Techniques that use some chemical agents allow a greater elimination of bacteria during the removal of carious tissue, without resorting to anesthesia, can be recommended as an alternative to traditional treatment especially in young children.

Biogenic silver nanoparticles as antifungal agents.

In recent years, an increase in multidrug-resistant fungal strains has been observed, which, together with the limited number of clinically available antifungal agents, highlights the need for the development of new antifungal agents. Due to the proven antifungal activity of silver nanoparticles (AgNPs), there is a growing interest in their use in the treatment of fungal infections. Nanoparticles are usually synthesised through a variety of physical and chemical processes that are costly and pollute the environment. For this reason, biogenic synthesis is emerging as an environmentally friendly technology and new strategies are increasingly based on the use of biogenic AgNPs as antifungal agents for clinical use. The aim of this review is to compare the antifungal activity of different biogenic AgNPs and to summarise the current knowledge on the mechanisms of action and resistance of fungi to AgNPs. Finally, a general analysis of the toxicity of biogenic AgNPs in human and veterinary medicine is performed.

Current situation of endemic mycosis in the Americas and the Caribbean: Proceedings of the first international meeting on endemic mycoses of the Americas (IMEMA).

BACKGROUND: The Americas are home to biologically and clinically diverse endemic fungi, including Blastomyces, Coccidioides, Emergomyces, Histoplasma, Paracoccidioides and Sporothrix. In endemic areas with high risk of infection, these fungal pathogens represent an important public health problem. OBJECTIVES: This report aims to summarise the main findings of the regional analysis carried out on the status of the endemic mycoses of the Americas, done at the first International Meeting on Endemic Mycoses of the Americas (IMEMA). METHODS: A regional analysis for the Americas was done, the 27 territories were grouped into nine regions. A SWOT analysis was done. RESULTS: All territories reported availability of microscopy. Seventy percent of territories reported antibody testing, 67% of territories reported availability of Histoplasma antigen testing. None of the territories reported the use of (1-3)-ß-d-glucan. Fifty two percent of territories reported the availability of PCR testing in reference centres (mostly for histoplasmosis). Most of the territories reported access to medications such as trimethoprim-sulfamethoxazole, itraconazole, voriconazole and amphotericin B (AMB) deoxycholate. Many countries had limited access to liposomal formulation of AMB and newer azoles, such as posaconazole and isavuconazole. Surveillance of these fungal diseases was minimal. CONCLUSIONS: A consensus emerged among meeting participants, this group concluded that endemic mycoses are neglected diseases, and due to their severity and lack of resources, the improvement of diagnosis, treatment and surveillance is needed.

Malassezia species: the need to establish epidemiological cutoff values.

Malassezia are common yeasts in human skin microbiome. Under certain conditions these yeasts may cause disease from skin disorders to systemic infections. In the absence of clinical breakpoints, epidemiological cutoff values (ECVs) are useful to differentiate isolates with acquired or mutational resistance. The aim of this work was to propose tentative ECVs of Malassezia furfur, M. sympodialis, M. globosa for fluconazole (FCZ), itraconazole (ITZ), voriconazole (VCZ), ketoconazole (KTZ) and amphotericin B (AMB). A total of 160 isolates (80 M. furfur, 50 M. sympodialis, and 30 M. globosa) were tested. Minimal inhibitory concentrations (MICs) were determined by modified broth microdilution method (CLSI). ECVs were estimated by ECOFFinder software and twofold dilutions beyond the mode. ITZ, KTZ, and VCZ showed the lowest MICs. The highest MIC and widest ranges were for FCZ and AMB. For ITZ, KTZ, and VCZ both ECVs were similar. For FCZ, AMB especially M. furfur, modal ECVs were lower than values obtained by statistical method. When MIC distribution is the only data available, ECV could provide information to help guide therapy decisions. In that drug/species combination in which different peaks in the MIC distribution were observed, difference between both ECV was greater. This is the first study that provides ECV data of 160 Malassezia yeasts. Although ECVs cannot be used as predictors of clinical response, identification of non wild-type isolates suggests that it may be less likely to respond to a given antifungal agent. LAY SUMMARY: Malassezia species causes skin disorders to systemic infections. Epidemiological cutoff value (ECV) allows for differentiation of wild-type and non wild-type isolates. Based on MIC data of 160 isolates we propose tentative ECVs for three Malassezia species. ECVs are useful in surveillance and guide therapy decisions.

Usefulness of Sona Aspergillus Galactomannan LFA with digital readout as diagnostic and as screening tool of COVID-19 associated pulmonary aspergillosis in critically ill patients. Data from a multicenter prospective study performed in Argentina.

COVID-19-associated pulmonary aspergillosis (CAPA) incidence varies depending on the country. Serum galactomannan quantification is a promising diagnostic tool since samples are easy to obtain with low biosafety issues. A multicenter prospective study was performed to evaluate the CAPA incidence in Argentina and to assess the performance of the lateral flow assay with digital readout (Sona Aspergillus LFA) as a CAPA diagnostic and screening tool. The correlation between the values obtained with Sona Aspergillus LFA and Platelia® EIA was evaluated. In total, 578 serum samples were obtained from 185 critically ill COVID patients. CAPA screening was done weekly starting from the first week of ICU stay. Probable CAPA incidence in critically ill patients was 10.27% (19/185 patients when LFA was used as mycological criteria) and 9% (9/100 patients when EIA was used as mycological criteria). We found a very good correlation between the two evaluated galactomannan quantification methods (overall agreement of 92.16% with a Kappa statistic value of 0.721). CAPA diagnosis (>0.5 readouts in LFA) were done during the first week of ICU stay in 94.7% of the probable CAPA patients. The overall mortality was 36.21%. CAPA patients' mortality and length of ICU stay were not statistically different from for COVID (non-CAPA) patients (42.11 vs 33.13% and 29 vs 24 days, respectively). These indicators were lower than in other reports. LFA-IMMY with digital readout is a reliable tool for early diagnosis of CAPA using serum samples in critically ill COVID patients. It has a good agreement with Platelia® EIA. LAY SUMMARY: The incidence of COVID-associated pulmonary aspergillosis (CAPA) in critically-ill Argentinian patients was established (10.27%). Serum galactomannan quantification was useful as a screening tool for this mycosis. A good agreement between Platelia® EIA and Sona Aspergillus LFA is reported.

Utilidad del panel Sensititre YeastOne® para detectar especies de Candida resistentes a los antifúngicos / Usefulness of the Sensititre YeastOne® panel to detect Candida species resistant to antifungal drugs

Resumen Evaluamos las concordancias interlaboratorio, esencial y categórica entre el panel Sensititre YeastOne™ y los métodos de referencia correspondientes al M27 4.a ed. (Clinical and Laboratory Standards Institute [CLSI]) y al EDef 7.3.1 (European Committee on Antifungal Susceptibility Testing [EUCAST]). Estudiamos 67 cepas de Candida de distintas muestras clí nicas y un panel de 9 cepas resistentes a fluconazol y equinocandinas. El mayor porcentaje de concordancia interlaboratorio se observó con anfotericina B (96,8%) y el menor porcen taje con voriconazol (77,2%). La caspofungina mostró un 5,8% de discrepancias muy mayores con el método de referencia del CLSI. Con el del EUCAST, el itraconazol, el posaconazol y la anidulafungina mostraron porcentajes de discrepancias mayores: el 17,6, el 18,1 y el 19,6%, respectivamente. El panel Sensititre YeastOne™ es una alternativa confiable y fácil de usar, que permite detectar especies de Candida resistentes a los antifúngicos, con algunas limitaciones para las equinocandinas. Los resultados son equiparables a los de los métodos de referencia.

Abstract We evaluated the interlaboratory agreement, the essential agreement, and the cate- gorical agreement between the Sensititre YeastOne™ panel and the reference methods M27 4th Edition of the Clinical and Laboratory Standards Institute (CLSI), and the EDef 7.3.1 of the Euro- pean Committee on Antifungal Susceptibility Testing (EUCAST). We studied 67 Candida strains isolated from different clinical samples and 9 Candida strains with resistance to fluconazole and echinocandins. The highest percentage of interlaboratory agreement was observed with amp- hotericin B (96.8%), and the lowest percentage with voriconazole (77.2%). Caspofungin showed 5.8% of very major errors when compared with the CLSI reference method. For EUCAST, itraconazole, posaconazole, and anidulafungin showed high percentages of major errors: 17.6%, 18.1%, and 19.6%, respectively. Sensititre YeastOne™ is a reliable alternative, and easy to perform for detecting Candida species resistant to antifungal drugs, with some limitations for echinocandins. Results are comparable to those of the reference methods.

Hepatic failure and malnutrition as predisposing factors of cutaneous mucormycosis in a pediatric patient.

The genus Lichtheimia is the third-most frequent genus isolated in mucormycosis. We report a cutaneous case caused by Lichtheimia ramosa, localized on the face of a pediatric patient, in the context of acute liver failure and caloric malnutrition. Several surgeries and treatment with liposomal amphotericin B enabled the patient's favorable evolution.

[Usefulness of the Sensititre YeastOne® panel to detect Candida species resistant to antifungal drugs]. / Utilidad del panel Sensititre YeastOne® para detectar especies de Candida resistentes a los antifúngicos.

We evaluated the interlaboratory agreement, the essential agreement, and the categorical agreement between the Sensititre YeastOneTM panel and the reference methods M27 4th Edition of the Clinical and Laboratory Standards Institute (CLSI), and the EDef 7.3.1 of the European Committee on Antifungal Susceptibility Testing (EUCAST). We studied 67 Candida strains isolated from different clinical samples and 9 Candida strains with resistance to fluconazole and echinocandins. The highest percentage of interlaboratory agreement was observed with amphotericin B (96.8%), and the lowest percentage with voriconazole (77.2%). Caspofungin showed 5.8% of very major errors when compared with the CLSI reference method. For EUCAST, itraconazole, posaconazole, and anidulafungin showed high percentages of major errors: 17.6%, 18.1%, and 19.6%, respectively. Sensititre YeastOneTM is a reliable alternative, and easy to perform for detecting Candida species resistant to antifungal drugs, with some limitations for echinocandins. Results are comparable to those of the reference methods.

Antimicrobial and cytotoxic activity of green synthesis silver nanoparticles targeting skin and soft tissue infectious agents.

Combining traditional medicine with nanotechnology therefore opens the door to innovative strategies for treating skin and soft tissue infections (SSTIs) and also contributes to the fight against the rise of antimicrobial resistance. Acanthospermum australe (Loefl.) Kuntze is a medicinal plant used by indigenous peoples in northeastern Argentina to treat SSTIs. Spherical and stable silver nanoparticles (AgNPs) of 14 ± 2 nm were synthesized from the aqueous extract of A. australe and silver nitrate. The antimicrobial activity against main species causing SSTIs and cytotoxicity on peripheral blood mononuclear cells of AgNP solution and its synthesis components were evaluated. Compared to its synthesis components, AgNP solution showed greater antimicrobial activity and lower cytotoxicity. The antimicrobial activity of AgNPs was due to the silver and not to the metabolites of the aqueous extract present on the surface of the nanoparticles. The plant extract played an important role in the formation of stable AgNPs and acted as a modulator of cytotoxic and immune responses.

Genomic diversity of the human pathogen Paracoccidioides across the South American continent.

Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease.