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Both Candida albicans and Issatchenkia orientalis have been isolated from different types of infections over the years. They have the ability to form communities of microorganisms known as biofilms. It has been demonstrated that the medium employed in studies may affect the biofilm development. The aim of this study was to investigate the arrangement of dual-species biofilms of C. albicans and I. orientalis cultivated on either RPMI-1640 or Sabouraud Dextrose Broth (SDB), as well as the inhibitory effect of Voriconazole (VRC). For the experiments performed, ATCC strains were used, and yeast-mixed suspensions were inoculated in 96-well plates with either RPMI-1640 or SDB, in the presence or absence of VRC. The results were observed by counting the number of CFU obtained from scraping off the biofilms produced and plating the content on CHROMagar Candida medium. It was observed that for all conditions tested the medium chosen affected the arrangement of dual-species biofilms: when RPMI-1640 was used, there was a prevalence of C. albicans, while the opposite was noted when SDB was used. It could be suggested that the medium and environment could regulate interactions between both yeast species, including the response to different antifungal drugs.

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Aim: This work aims to standardize the three-dimensional hydroxyethyl-alginate-gelatin (HAG) scaffold as a model to evaluate Aspergillus fumigatus biofilm and antifungal treatments. Methods: The scaffold was characterized by physical, rheological and microscopic analyses; the antibiofilm action was evaluated by determination of cfu and metabolic activity. Results: The scaffold was non-toxic showing stability in aqueous media, swelling capacity, elasticity and had homogeneously distributed pores averaging 190 µm. The A. fumigatus biofilm established itself very well on the scaffold and treatment with amphotericin B and voriconazole reduced viable cells and metabolic activity. Conclusion: The HAG scaffold proved to be a model to mimic lung parenchyma, suitable for establishing a 3D biofilm culture of A. fumigatus and evaluating the efficacy of antifungals.

[Box: see text].

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Aspergillosis is an infrequent infection in the Central Nervous System with a mortality rate higher than 95 %. Early diagnosis is challenging and crucial. In this report, we present the case of a six-year-old female with an intense headache accompanied by left hemiparesis, gaze deviation, horizontal nystagmus, and vomiting of mucous content on five occasions. After several approaches, a cerebrospinal fluid PCR resulted positive for Aspergillus spp., and then management started with amphotericin B at 2.6 mg/kg/day and was managed to have voriconazole. She survived, and two years after her first hospital admission, she suffered from cerebral aspergillosis sequelae. An area of improvement is the coordination between the request and delivery of studies outside the institution. In this case, the patient´s mother did not report the analysis results on time, delaying the diagnosis.

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RESUMEN La aspergilosis pulmonar, causada por el hongo oportunista Aspergillus, afecta principalmente a individuos inmunocomprometidos. Este reporte presenta tres casos: Una mujer de 18 años con leucemia aguda desarrolló dificultad respiratoria y patrones bilaterales de "árbol en brote" en la tomografía computarizada (TC). A pesar del tratamiento con voriconazol, falleció debido a insuficiencia respiratoria. Una mujer de 58 años con diabetes y EPOC presentó disnea y hemoptisis. Las imágenes revelaron una lesión cavitada, confirmando un aspergiloma. Se consideró la cirugía debido a la hemoptisis activa. Una mujer de 41 años con antecedentes de tuberculosis presentó fiebre y síntomas respiratorios. La TC mostró lesiones cavitadas y bronquiectasias, confirmando aspergilosis crónica. Respondió bien al voriconazol. Estos casos destacan la variabilidad en la aspergilosis pulmonar y subrayan la importancia de un diagnóstico y tratamiento oportunos para mejorar los resultados en los pacientes.

ABSTRACT Pulmonary aspergillosis, caused by the opportunistic fungus Aspergillus, primarily affects immunocompromised individuals. This report presents three cases: An 18-year-old female with acute leukemia developed respiratory distress and bilateral "tree-in-bud" patterns on CT. Despite voriconazole treatment, she succumbed to respiratory failure. A 58-year-old female with diabetes and COPD had dyspnea and hemoptysis. Imaging revealed a cavitated lesion, confirming aspergilloma. Surgery was considered due to active hemoptysis. A 41-year-old female with a history of tuberculosis presented with fever and respiratory symptoms. CT showed cavitated lesions and bronchiectasis, confirming chronic aspergillosis. She responded well to voriconazole. These cases highlight the variability in pulmonary aspergillosis and underscore the importance of timely diagnosis and treatment to improve patient outcomes.

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INTRODUCTION: A specialized service for antifungal blood level determination is not available in Colombia. This service is essential for the proper follow-up of antifungal therapies. OBJECTIVE: To standardize and validate a simple, sensitive, and specific protocol based on high-performance liquid chromatography with a diode array detector for voriconazole blood level quantification. MATERIALS AND METHODS: We used an Agilent HPLC™ series-1200 equipment with a UVdiode array detector with an analytical column Eclipse XDB-C18 and pre-column Eclipse- XDB-C18 (Agilent). We used voriconazole as the primary control and posaconazole as an internal control. We performed the validation following the Food and Drug Administration (FDA) recommendations. RESULTS: The best chromatographic conditions were: Column temperature of 25°C, UV variable wavelength detection at 256 nm for voriconazole and 261 nm for posaconazole (internal standard); 50 µl of injection volume, 0,8 ml/min volume flow, 10 minutes of run time, and mobile phase of acetonitrile:water (60:40). Finally, retention times were 3.13 for voriconazole and 5.16 minutes for posaconazole. Quantification range varied from 0.125 µg/ml to 16 µg/ml. CONCLUSION: The selectivity and chromatographic purity of the obtained signal, the detection limits, and the standardized quantification make this method an excellent tool for the therapeutic monitoring of patients treated with voriconazole.

Introducción. Hasta la fecha, Colombia no cuenta con un servicio especializado de medición de niveles séricos de antifúngicos, procedimiento esencial para el adecuado seguimiento del tratamiento de infecciones fúngicas invasoras. Objetivo. Estandarizar y validar un protocolo ­simple, sensible y específico­ basado en la aplicación de cromatografía líquida de alta eficiencia acoplada con un detector de arreglo de diodos para la cuantificación de los niveles séricos de voriconazol. Materiales y métodos. Se usó un equipo HPLC-Agilent™, serie-1200, con un detector UVDAD, una columna analítica Eclipse-XDB-C18 y una pre-columna Eclipse-XDB-C18, ambas de la marca Agilent. Como control primario se utilizó voriconazol y como control interno, posaconazol. La validación se hizo cumpliendo todos los criterios de aceptación recomendados por la Food and Drug Administration (FDA). Resultados. Las mejores condiciones cromatográficas se obtuvieron con los siguientes parámetros: temperatura de la columna de 25 °C, detección UV-VWD de 261 nm, volumen de inyección de 50 µl, flujo de 0,8 ml/minuto y un tiempo de corrido de 10 minutos. La fase móvil usada fue acetonitrilo:agua (60:40) y los tiempos finales de retención fueron de 3,13 para voriconazol y de 5,16 minutos para posaconazol. El rango de cuantificación fue desde 0,125 µg/ml hasta 16 µg/ml. Conclusiones. La selectividad y la pureza de la señal cromatográfica, así como los límites de detección y cuantificación estandarizados hacen de esta metodología una excelente herramienta para el seguimiento terapéutico de pacientes tratados con voriconazol o en profilaxis con este fármaco.

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Introduction. A specialized service for antifungal blood level determination is not available in Colombia. This service is essential for the proper follow-up of antifungal therapies. Objective. To standardize and validate a simple, sensitive, and specific protocol based on high-performance liquid chromatography with a diode array detector for voriconazole blood level quantification. Materials and methods. We used an Agilent HPLC™ series-1200 equipment with a UV- diode array detector with an analytical column Eclipse XDB-C18 and pre-column Eclipse-XDB-C18 (Agilent). We used voriconazole as the primary control and posaconazole as an internal control. We performed the validation following the Food and Drug Administration (FDA) recommendations. Results. The best chromatographic conditions were: Column temperature of 25°C, UV variable wavelength detection at 256 nm for voriconazole and 261 nm for posaconazole (internal standard); 50 µl of injection volume, 0,8 ml/min volume flow, 10 minutes of run time, and mobile phase of acetonitrile:water (60:40). Finally, retention times were 3.13 for voriconazole and 5.16 minutes for posaconazole. Quantification range varied from 0.125 µg/ml to 16 µg/ml. Conclusion. The selectivity and chromatographic purity of the obtained signal, the detection limits, and the standardized quantification make this method an excellent tool for the therapeutic monitoring of patients treated with voriconazole.

Introducción. Hasta la fecha, Colombia no cuenta con un servicio especializado de medición de niveles séricos de antifúngicos, procedimiento esencial para el adecuado seguimiento del tratamiento de infecciones fúngicas invasoras. Objetivo. Estandarizar y validar un protocolo ­simple, sensible y específico­ basado en la aplicación de cromatografía líquida de alta eficiencia acoplada con un detector de arreglo de diodos para la cuantificación de los niveles séricos de voriconazol. Materiales y métodos. Se usó un equipo HPLC-Agilent™, serie-1200, con un detector UVDAD, una columna analítica Eclipse-XDB-C18 y una pre-columna Eclipse-XDB-C18, ambas de la marca Agilent. Como control primario se utilizó voriconazol y como control interno, posaconazol. La validación se hizo cumpliendo todos los criterios de aceptación recomendados por la Food and Drug Administration (FDA). Resultados. Las mejores condiciones cromatográficas se obtuvieron con los siguientes parámetros: temperatura de la columna de 25 °C, detección UV-VWD de 261 nm, volumen de inyección de 50 µl, flujo de 0,8 ml/minuto y un tiempo de corrido de 10 minutos. La fase móvil usada fue acetonitrilo:agua (60:40) y los tiempos finales de retención fueron de 3,13 para voriconazol y de 5,16 minutos para posaconazol. El rango de cuantificación fue desde 0,125 µg/ml hasta 16 µg/ml. Conclusiones. La selectividad y la pureza de la señal cromatográfica, así como los límites de detección y cuantificación estandarizados hacen de esta metodología una excelente herramienta para el seguimiento terapéutico de pacientes tratados con voriconazol o en profilaxis con este fármaco.

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Extracorporeal photopheresis is an established procedure for refractory graft-versus-host disease, a major complication associated with notable morbidity and mortality in patients with allogeneic hematopoietic stem cell transplant. Despite being implemented over a decade ago, there is scant information about potential interactions or analytical interferences with concomitant drugs in this polymedicated population. Here we report the case of a pediatric patient diagnosed with cutaneous steroid-refractory acute graft-versus-host disease after unrelated allogeneic hematopoietic stem cell transplant that was treated with photopheresis. Analytical quantification of voriconazole by HPLC-PDA the day following photopheresis treatment did not permit therapeutic drug monitoring (TDM) due to the presence of interference at the voriconazole retention time. Following investigations, it was demonstrated that the interference is likely attributable to a psoralen-based compound. The interference was not present when samples were obtained prior to photopheresis, enabling TDM. This case underscores the relevance of communication among the members of the treating team to perform reliable TDM, especially in routine clinical practice of pediatric patients with complex diseases undergoing innovative treatments. This finding is relevant to voriconazole quantification by HPLC-PDA, frequently used in laboratories based in middle-income countries.

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Fungemia caused by Geotrichum spp. is rare and highly lethal. The Instituto Nacional de Cancerología in Bogotá reported just two cases: one in the period 2001-2007 and the other in 2012-2018. This type of infection is more common in any kind of immunocompromised patients, so it can occur in those with hematological malignancies. Here we present the case of a 27-year-old man, diagnosed with acute lymphoblastic leukemia in relapse and admitted with polyarthralgia for five days, febrile neutropenia, nonabscessed cellulitis, and bacteremia due to methicillin-sensitive Staphylococcus aureus. The patient received therapy with oxacillin and cefepime, but the febrile neutropenia persisted. A new set of blood cultures was taken, and antifungal treatment was started because of the suspicion of invasive fungal infection. Arthroconidia were identified in blood cultures and Geotrichum spp. was confirmed using matrix-assisted laser desorption-ionization mass spectrometry. The antifungal treatment was adjusted with amphotericin B deoxycholate for 14 days and voriconazole for four weeks, and after a prolonged stay, the patient was discharged. Although the incidence of fungemia caused by Geotrichum spp. is low, it must be considered in patients with hematological malignancies and persistent febrile neutropenia despite the broadspectrum antimicrobial treatment. The confirmation of fungemia causing agents, with proteomic tools such as the mentioned mass spectrometry, allows treatment adjustment and decreases complications, hospital stay, and mortality.

La fungemia por Geotrichum spp. es poco frecuente y altamente letal. En el Instituto Nacional de Cancerología de Bogotá solo se han reportado dos casos: uno entre el 2001 y el 2007, y el otro entre el 2012 y el 2018. Este tipo de infección es más común en pacientes con algún grado de compromiso del sistema inmunitario, por lo que puede presentarse en pacientes con neoplasias hematológicas malignas. Se presenta el caso de un hombre de 27 años con recaída de leucemia linfoblástica aguda, que ingresó con poliartralgias de cinco días de duración. También cursaba con neutropenia febril, celulitis sin abscesos y bacteriemia por Staphylococcus aureus resistente a la meticilina para lo cual recibió terapia con oxacilina y cefepime. Sin embargo, persistía la neutropenia febril por lo que se sospechó una infección fúngica invasora. Se tomó un nuevo set de hemocultivos y se inició tratamiento antifúngico. En los hemocultivos se identificaron artroconidias y mediante espectrometría de masas por láser de matriz asistida de ionización-desorción se confirmó la presencia de Geotrichum spp. Se ajustó el tratamiento antifúngico con deoxicolato de anfotericina B por 14 días y voriconazol por cuatro semanas. Luego de una estancia prolongada se le dio de alta. Aunque la incidencia de la fungemia por Geotrichum spp. es baja, en pacientes con neoplasias hematológicas malignas debe considerarse en el contexto de una neutropenia febril que es persistente a pesar del tratamiento antimicrobiano de amplio espectro.

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Voriconazole is a triazole antifungal used empirically for the treatment of complicated meningitis associated with Cryptococcus neoformans. Biopsy studies show that the drug exhibits adequate brain penetration although levels of cerebral spinal fluid (CSF) are highly variable. Considering that CSF is one of the main surrogates for CNS exposure, the present work proposed the building of a population pharmacokinetic modeling (popPK) model able to describing the exposure achieved by voriconazole in the plasma, interstitial cerebral fluid and CSF of healthy and infected rats. The developed popPK model was described by four compartments, including total plasma, free brain and total CSF concentrations. The following PK parameters were determined: Km = 4.76 mg/L, Vmax = 1.06 mg/h, Q1 = 2.69 L, Qin = 0.81 h-1 and Qout = 0.63 h-1. Infection was a covariate in the Michaelis-Menten constant (Km) and intercompartmental clearance from the brain tissue compartment to central compartment (Qout). Simulations performed with the popPK model to determine the probability of reaching the therapeutic target of fAUC > MIC showed that VRC has sufficient tissue exposure in the interstitial fluid and in the CSF for the treatment of fungal infections in these tissues at prevalent minimum inhibitory concentrations.

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Cryptococcus neoformans and Cryptococcus gattii cause cryptococcosis, a life-threatening fungal infection affecting mostly immunocompromised patients. In fact, cryptococcal meningitis accounts for about 19% of AIDS-related deaths in the world. Because of long-term azole therapies to treat this mycosis, resistance to fluconazole leading to treatment failure and poor prognosis has long been reported for both fungal species. Among the mechanisms implicated in resistance to azoles, mutations in the ERG11 gene, encoding the azole target enzyme lanosterol 14-α-demethylase, have been described. This study aimed to establish the amino acid composition of ERG11 of Colombian clinical isolates of C. neoformans and C. gattii and to correlate any possible substitution with the in vitro susceptibility profile of the isolates to fluconazole, voriconazole, and itraconazole. Antifungal susceptibility testing results showed that C. gattii isolates are less susceptible to azoles than C. neoformans isolates, which could correlate with differences in the amino acid composition and structure of ERG11 of each species. In addition, in a C. gattii isolate with high MICs for fluconazole (64 µg/mL) and voriconazole (1 µg/mL), a G973T mutation resulting in the substitution R258L, located in substrate recognition site 3 of ERG11, was identified. This finding suggests the association of the newly reported substitution with the azole resistance phenotype in C. gattii. Further investigations are needed to determine the exact role that R258L plays in the decreased susceptibility to fluconazole and voriconazole, as well as to determine the participation of additional mechanisms of resistance to azole drugs. IMPORTANCE The fungal species Cryptococcus neoformans and C. gattii are human pathogens for which drug resistance or other treatment and management challenges exist. Here, we report differential susceptibility to azoles among both species, with some isolates displaying resistant phenotypes. Azoles are among the most commonly used drugs to treat cryptococcal infections. Our findings underscore the necessity of testing antifungal susceptibility in the clinical setting in order to assist patient management and beneficial outcomes. In addition, we report an amino acid change in the sequence of the target protein of azoles, which suggests that this change might be implicated in resistance to these drugs. Identifying and understanding possible mechanisms that affect drug affinity will eventually aid the design of new drugs that overcome the global growing concern of antifungal resistance.

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Resumen La aspergilosis invasiva (AI) es una enfermedad grave y con alta mortalidad. Existen factores de riesgo y se describen brotes intrahospitalarios relacionados con construcciones. También se des cribe una entidad relacionada con la infección por COVID-19, conocida como aspergilosis pulmonar asociada a COVID-19 (APAC). Es de vital importancia implementar un tratamiento adecuado y precoz, especialmente en pacientes inmunocomprometidos y críticamente enfermos. El diagnóstico se basa en reconocer los factores predisponentes, la clínica, la obtención de imágenes, exámenes directos, cultivos, histopatología y biomarca dores como el galactomanano. La droga de elección es el voriconazol, pero se deben conocer las alternativas terapéuticas dada la creciente presencia de aislamientos resistentes.

Abstract Invasive aspergillosis (IA) is a serious disease with high mortality. There are several risk factors and in-hospital outbreaks related with construction have been described. An entity related to COVID-19 infection, known as COVID-19 associated pulmonary aspergillosis (CAPA), has recently appeared. Early and appropriate treatment is of paramount importance, especially in immunocompromised and critically ill patients. Diagnosis is based on recognition of predisposing factors, clinical signs, imaging, direct examination, culture, histopathology, and biomarkers such as galactomannan. The drug of choice is voriconazole, but alternative therapies must be taken into account given the increasing presence of resistant isolates.

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Invasive aspergillosis (IA) is a serious disease with high mortality. There are several risk factors and in-hospital outbreaks related with construction have been described. An entity related to COVID-19 infection, known as COVID-19 associated pulmonary aspergillosis (CAPA), has recently appeared. Early and appropriate treatment is of paramount importance, especially in immunocompromised and critically ill patients. Diagnosis is based on recognition of predisposing factors, clinical signs, imaging, direct examination, culture, histopathology, and biomarkers such as galactomannan. The drug of choice is voriconazole, but alternative therapies must be taken into account given the increasing presence of resistant isolates.

La aspergilosis invasiva (AI) es una enfermedad grave y con alta mortalidad. Existen factores de riesgo y se describen brotes intrahospitalarios relacionados con construcciones. También se describe una entidad relacionada con la infección por COVID-19, conocida como aspergilosis pulmonar asociada a COVID-19 (APAC). Es de vital importancia implementar un tratamiento adecuado y precoz, especialmente en pacientes inmunocomprometidos y críticamente enfermos. El diagnóstico se basa en reconocer los factores predisponentes, la clínica, la obtención de imágenes, exámenes directos, cultivos, histopatología y biomarcadores como el galactomanano. La droga de elección es el voriconazol, pero se deben conocer las alternativas terapéuticas dada la creciente presencia de aislamientos resistentes.

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Invasive fungal infections (IFIs) are a major cause of morbidity and mortality among immunocompromised patients with underlying malignancies and prior transplants. FDA approved Isavuconazole as a primary therapy for Invasive Aspergillosis (IA) and Mucormycosis. This study aims to compare the real-world clinical outcomes and safety of isavuconazole to voriconazole and an amphotericin B-based regimen in patients with underlying malignancies and a transplant. In addition, the response to anti-fungal therapy and the outcome were compared among patients with a disparity (elderly, obese patients, patients with renal insufficiency and diabetes mellitus) versus those with no disparity. We performed a multicenter retrospective study, including patients with cancer diagnosed with an invasive fungal infection, and treated primarily with isavuconazole, voriconazole or amphotericin B. Clinical, radiologic findings, response to therapy and therapy related adverse events were evaluated during 12 weeks of follow-up. We included 112 patients aged 14 to 77 years, and most of the IFIs were classified into definite (29) or probable (51). Most cases were invasive aspergillosis (79%), followed by fusariosis (8%). Amphotericin B were used more frequently as primary therapy (38%) than isavuconazole (30%) or voriconazole (31%). Twenty one percent of the patients presented adverse events related to primary therapy, with patients receiving isavuconazole presenting less adverse events when compared to voriconazole and amphotericin (p < 0.001; p = 0.019). Favorable response to primary therapy during 12 weeks of follow-up were similar when comparing amphotericin B, isavuconazole or voriconazole use. By univariate analysis, the overall cause of mortality at 12 weeks was higher in patients receiving amphotericin B as primary therapy. However, by multivariate analysis, Fusarium infection, invasive pulmonary infection or sinus infection were the only independent risk factors associated with mortality. In the treatment of IFI for patients with underlying malignancy or a transplant, Isavuconazole was associated with the best safety profile compared to voriconazole or amphotericin B-based regimen. Regardless of the type of anti-fungal therapy used, invasive Fusarium infections and invasive pulmonary or sinus infections were the only risk factors associated with poor outcomes. Disparity criteria did not affect the response to anti-fungal therapy and overall outcome, including mortality.

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La fungemia por Geotrichum spp. es poco frecuente y altamente letal. En el Instituto Nacional de Cancerología de Bogotá solo se han reportado dos casos: uno entre el 2001 y el 2007, y el otro entre el 2012 y el 2018. Este tipo de infección es más común en pacientes con algún grado de compromiso del sistema inmunitario, por lo que puede presentarse en pacientes con neoplasias hematológicas malignas. Se presenta el caso de un hombre de 27 años con recaída de leucemia linfoblástica aguda, que ingresó con poliartralgias de cinco días de duración. También cursaba con neutropenia febril, celulitis sin abscesos y bacteriemia por Staphylococcus aureus resistente a la meticilina para lo cual recibió terapia con oxacilina y cefepime. Sin embargo, persistía la neutropenia febril por lo que se sospechó una infección fúngica invasora. Se tomó un nuevo set de hemocultivos y se inició tratamiento antifúngico. En los hemocultivos se identificaron artroconidias y mediante espectrometría de masas por láser de matriz asistida de ionización-desorción se confirmó la presencia de Geotrichum spp. Se ajustó el tratamiento antifúngico con deoxicolato de anfotericina B por 14 días y voriconazol por cuatro semanas. Luego de una estancia prolongada se le dio de alta. Aunque la incidencia de la fungemia por Geotrichum spp. es baja, en pacientes con neoplasias hematológicas malignas debe considerarse en el contexto de una neutropenia febril que es persistente a pesar del tratamiento antimicrobiano de amplio espectro. La identificación de los agentes causantes de fungemias con herramientas de proteómica, como la espectrometría de masas mencionada, permite ajustar el tratamiento dirigido y reducir las complicaciones, la estancia hospitalaria y la mortalidad.

Fungemia caused by Geotrichum spp. is rare and highly lethal. The Instituto Nacional de Cancerología in Bogotá reported just two cases: one in the period 2001-2007 and the other in 2012-2018. This type of infection is more common in any kind of immunocompromised patients, so it can occur in those with hematological malignancies. Here we present the case of a 27-year-old man, diagnosed with acute lymphoblastic leukemia in relapse and admitted with polyarthralgia for five days, febrile neutropenia, non- abscessed cellulitis, and bacteremia due to methicillin-sensitive Staphylococcus aureus. The patient received therapy with oxacillin and cefepime, but the febrile neutropenia persisted. A new set of blood cultures was taken, and antifungal treatment was started because of the suspicion of invasive fungal infection. Arthroconidia were identified in blood cultures and Geotrichum spp. was confirmed using matrix-assisted laser desorption-ionization mass spectrometry. The antifungal treatment was adjusted with amphotericin B deoxycholate for 14 days and voriconazole for four weeks, and after a prolonged stay, the patient was discharged. Although the incidence of fungemia caused by Geotrichum spp. is low, it must be considered in patients with hematological malignancies and persistent febrile neutropenia despite the broadspectrum antimicrobial treatment. The confirmation of fungemia causing agents, with proteomic tools such as the mentioned mass spectrometry, allows treatment adjustment and decreases complications, hospital stay, and mortality.

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La fusariosis es una micosis oportunista producida por Fusarium spp. Su presentación clínica depende del estado inmunológico del huésped, especialmente, el de aquellos con enfermedades hematooncológicas, cuyas manifestaciones varían desde formas localizadas hasta infección fúngica invasora. El cultivo de piel o de sangre permite orientar el tratamiento antifúngico combinado con anfotericina B y voriconazol. Se presentan 13 casos de pacientes con cáncer en un periodo de once años que desarrollaron fusariosis diseminada; asimismo, se hizo con una revisión extensa de la literatura. En esta serie de casos, la mortalidad fue del 61,5 % (8/13), a pesar del uso del antifúngico. De los 13 pacientes, 11 tenían neoplasia hematológica y 2 neoplasia sólida. El factor de riesgo más importante fue la neutropenia profunda. El compromiso de la piel y los hemocultivos positivos facilitaron la prescripción del tratamiento combinado en la mayoría de los casos. La neutropenia febril persistente asociada a lesiones cutáneas, la onicomicosis, los nódulos o las masas pulmonares permitieron sospechar una infección fúngica invasora por Fusarium spp. El objetivo de la presentación de esta serie de casos es recordar el diagnóstico de fusariosis a la comunidad médica en contacto con pacientes oncológicos, con neutropenia febril profunda y persistentes.

The fusariosis is an opportunistic mycosis caused by Fusarium spp. Its clinical presentation depends on the immunological status of the host, especially in patients with hemato-oncological diseases, whose manifestations vary from localized to invasive fungal infections. Skin or blood culture helps to guide combined antifungal treatment with amphotericin B and voriconazole. Here, we present 13 cases in a period of eleven years of patients with cancer who developed disseminated fusariosis and their outcomes, together with a review of the related literature. In this series of cases, mortality was 61.5 % (8/13), despite the use of the antifungal. Out of the 13 cases, 11 had hematological neoplasia and 2 solid neoplasia. The most determinant risk factor was profound neutropenia. Skin involvement and positive blood cultures in most cases allowed combined treatment prescription. Persistent febrile neutropenia associated with skin lesions, onychomycosis, nodules, or lung masses lead to suspicion of Fusarium spp. fungal invasive infection. The aim of this series of cases is to remind healthcare professionals that oncological patients with deep and persistent febrile neutropenia can develop fusariosis.

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Onychomycosis is the most common disease affecting the nail unit and accounts for at least 50% of all nail diseases. In addition, Candida albicans is responsible for approximately 70% of onychomycoses caused by yeasts. This study investigated the antifungal effect of (R) and (S)-citronellal enantiomers, as well as its predictive mechanism of action on C. albicans from voriconazole-resistant onychomycoses. For this purpose, in vitro broth microdilution and molecular docking techniques were applied in a predictive and complementary manner to the mechanisms of action. The main results of this study indicate that C. albicans was resistant to voriconazole and sensitive to the enantiomers (R) and (S)-citronellal at a dose of 256 and 32 µg/mL respectively. In addition, there was an increase in the minimum inhibitory concentration (MIC) of the enantiomers in the presence of sorbitol and ergosterol, indicating that these molecules possibly affect the integrity of the cell wall and cell membrane of C. albicans. Molecular docking with key biosynthesis proteins and maintenance of the fungal cell wall and plasma membrane demonstrated the possibility of (R) and (S)-citronellal interacting with two important enzymes: 1,3-ß-glucan synthase and lanosterol 14α-demethylase. Therefore, the findings of this study indicate that the (R) and (S)-citronellal enantiomers are fungicidal on C. albicans from onychomycoses and probably these substances cause damage to the cell wall and cell membrane of these micro-organisms possibly by interacting with enzymes in the biosynthesis of these fungal structures.

A onicomicose é a doença mais comum que afeta a unidade ungueal e representa pelo menos 50% de todas as doenças ungueais. Além disso, a Candida albicans é responsável por aproximadamente 70% das onicomicoses causadas por leveduras. Nesse estudo, foi investigado o efeito antifúngico dos enantiômeros (R) e (S)-citronelal, bem como seu mecanismo de ação preditivo sobre C. albicans de onicomicoses resistentes ao voriconazol. Para este propósito, foram aplicadas técnicas in vitro de microdiluição em caldo e docking molecular de forma preditiva e complementar para os mecanismos de ação. Os principais resultados deste estudo indicam que C. albicans foi resistente ao voriconazol e sensível aos enantiômeros (R) e (S)-citronelal na dose de 256 e 32 µg/mL respectivamente. Além disso, houve aumento da concentração inibitória mínima (CIM) dos enantiômeros na presença do sorbitol e do ergosterol, indicando que estas moléculas possivelmente afetem a integridade da parede e da membrana celular de C. albicans. O docking molecular com proteínas chave da biossíntese e manutenção da parede celular e da membrana plasmática fúngica, demonstraram a possibilidade do (R) e (S)-citronelal interagir com duas importantes enzimas: 1,3-ß-glucan sintase e lanosterol 14α-demetilase. Portanto, os achados desse estudo indicam que os enantiômeros (R) e (S)-citronelal são fungicidas sobre C. albicans de onicomicoses e provavelmente essas substâncias causem danos a parede e a membrana celular desses microrganismos possivelmente por interagir com as enzimas da biossíntese destas estruturas fúngicas.

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Abstract Voriconazole increases tacrolimus blood concentration significantly when coadministrated. The recommendation of reducing tacrolimus to 1/3 in voriconazole package insert seems not to be satisfactory in clinical practice. In vitro studies demonstrated that the magnitude of inhibition depends on the concentration of voriconazole, while voriconazole exposure is determined by the genotype status of CYP2C19. CYP2C19 gene polymorphism challenges the management of drug-drug interactions(DDIs) between voriconazole and tacrolimus. This work aimed to predict the impact of CYP2C19 polymorphism on the DDIs by using physiologically based pharmacokinetics (PBPK) models. The precision of the developed voriconazole and tacrolimus models was reasonable by evaluating the pharmacokinetic parameters fold error, such as AUC0-24, Cmax and tmax. Voriconazole increased tacrolimus concentration immediately in all population. The simulated duration of DDIs disappearance after voriconazole withdrawal were 146h, 90h and 66h in poor metabolizers (PMs), intermediate metabolizers (IMs) and extensive metabolizers(EMs), respectively. The developed and optimized PBPK models in this study can be applied to assit the dose adjustment for tacrolimus with and without voriconazole.

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Trichosporon asahii and T. inkin are emergent agents of deep-seated and disseminated infections in immunocompromised patients. The present study aimed to investigate the role of extracellular DNA (eDNA) and the enzyme deoxyribonuclease (DNase) on the structure of T. asahii and T. inkin biofilms, as well as to examine their effect on the susceptibility to antifungals. Biofilms reached maturity at 48 h; eDNA concentration in the supernatant increased over time (6 < 24 h < 48h). Exogenous eDNA increased biomass of Trichosporon biofilms at all stages of development, enhanced their tolerance to antifungals and improved their structural complexity. DNase reduced biomass, biovolume and thickness of Trichosporon biofilms, thereby rendering them more susceptibility to voriconazole. The results suggest the relevance of eDNA in the structure and antifungal susceptibility of Trichosporon biofilms and highlight the potential of DNase as adjuvant in biofilm control.

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Candida auris is an emerging global public health threat. It is an opportunistic yeast that usually affects critically ill patients in healthcare settings and is characterized by reduced susceptibility to multiple antifungal classes. Combination therapy with antifungals and repurposed drugs is a feasible alternative to overcome this problem. The aim of this study was to examine the in vitro interactions and potential synergy of micafungin (MFG) and voriconazole (VRC) plus the antidepressant sertraline (SRT) against clinical isolates of C. auris. Conventional antifungal testing was first performed with the three drugs according to the CLSI methodology. Drug interactions were determined by the checkerboard microdilution assay using the fractional inhibitory concentration (FIC) index. Synergistic interactions were noted with the combination of MFG and SRT plus VRC with FIC values of 0.37 to 0.49 for some strains. Indifferent interactions were observed when MFG was combined with SRT with just one exception (FIC 0.53). No antagonism was observed for any combination. The combination of VRC with MCF or SRT may be relevant for treating C. auris infections.

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Resumen Presentamos el caso de un escolar de 10 años, con el diagnóstico de una recaída de una leucemia mieloide aguda que cursó con un episodio de una neutropenia febril de alto riesgo, posterior a un ciclo intensivo de quimioterapia, evolucionando con una infección fúngica invasora demostrada por histopatología. Se inició tratamiento con voriconazol intravenoso, evolucionando con concentraciones plasmáticas erráticas que requirieron sucesivos ajustes de dosis, lo que también ocurrió con la administración oral del medicamento. Finalmente, tuvo una respuesta favorable al tratamiento, a pesar de la dificultad de la dosificación para alcanzar niveles terapéuticos. La búsqueda activa y la terapia antifúngica anticipada, así como la monitorización seriada de concentraciones terapéuticas de voriconazol, permitieron un tratamiento antifúngico óptimo y oportuno, mejorando el pronóstico del paciente.

Abstract We present a 10-year-old male patient with a diagnosis of relapsed acute myeloid leukemia (AML), presenting with high-risk febrile neutropenia (HRFN), after a cycle of intensive chemotherapy, evolving with an invasive fungal infection demonstrated by histopathology. Treatment with intravenous voriconazole was started, with erratic plasmatic levels, which require successive dose adjustments which also occurred with oral administration. Finally, he had a favorable response to treatment, despite of the dosing difficulties to reach therapeutic levels. Active search as well as preemptive antifungal therapy, together with plasmatic level monitorization of voriconazole allowed a prompt recovery and improved the patient prognosis.

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