Epidemiological indicators and predictors of lethality associated with fungal infections in a NICU: a historical series

Abstract Objectives: Fungal infections (FI) pose a public health concern and significantly increase mortality rates, especially within Neonatal Intensive Care Units (NICU). Thus, this study aimed to investigate epidemiological indicators, risk factors, and lethality predictors associated with FI in a NICU. Methods: This study included 1,510 neonates admitted to the NICU of a reference hospital in Brazil between 2015 and 2022. Demographic data, such as sex, birth weight, gestational age, and use of invasive devices were analyzed. Results: Thirty neonates developed invasive FI, totaling 33 episodes and an incidence of 1.2 per 1,000 patient days. Candida albicans was the most frequent species (52.9 %), the bloodstream was the most affected site (78.9 %), and 72.7 % of infections occurred between 2015 and 2018. The lethality rate associated with FI was 33.3 %, and 90 % of deaths occurred within 30 days of diagnosis of infection. Weight < 750 g, prolonged hospital stay, use of parenteral nutrition, and broad-spectrum antimicrobials were independent risk factors for infection occurrence, especially glycopeptides and 4th generation cephalosporins, having a considerable role in the increase in fungal infections. Weight < 750 g was considered a significant predictor of lethality, and C. albicans had the highest lethality rate (40 %). Conclusion: These findings highlight the elevated lethality rate associated with these infections, reinforcing the importance of developing strategies to control FI within NICU.

Ação antifúngica de extratos de plantas isolados sobre espécies de Candida albicans e Candida não-albicans / Antifungal action of isolated plant extracts on Candida albicans and Candida non-albicans species

As espécies de Candida spp. apresentam-se como o principal patógeno fúngico humano, podendo causar infecções superficiais e invasivas. A emergência de novas espécies em infecções, apresentando alta resistência aos antifúngicos utilizados desafia pesquisadores a propor novas terapias no controle desta infecção, entre as quais podemos citar a fitoterapia realizando o uso de extratos de plantas para propor novos protocolos. Por isto, este trabalho objetiva avaliar a ação antifúngica dos extratos isolados de Quilaia (Quillaja saponaria) e Alcachofra (Cynara scolymus) sobre C. albicans, C. glabrata, C. krusei, C. tropicalis e C. dubliniensis em formas planctônica e biofilmes monotípicos. Inicialmente foram feitas análises da ação antifúngica dos extratos de Quilaia e Alcachofra por meio do teste de microdiluição em caldo (CLSI ­ Protocolo M27-S4), para determinar as Concentrações Inibitórias Mínimas (CIM) e as Concentrações Fungicidas Mínimas (CFM) de espécies. Os biofilmes foram formados por 48 h em poços de microplacas, os quais receberam tratamentos de concentrações dos extratos (100 mg/mL, 50 mg/mL, 25 mg/mL, 12,5 mg/mL e 6,25 mg/mL), assim como foram testados os grupos controles positivo e negativo, para determinação da viabilidade celular por meio do teste MTT. Os dados foram analisados estatísticamente pelos testes ANOVA e Tukey, com significância de 5%. Os resultados da CIM e CFM para as espécies C. albicans, C. krusei e C. glabrata foram de 12,5mg/mL para ambos os extratos, os valores para C tropicalis foi 12,5 mg/mL para o extrato de Quilaia e 25 mg/mL para Alcachofra, ambos os extratos apresentaram o mesmo valor de 6,25 mg/mL para a espécie C. dubliniensis. A ação antibiofilme do extrato de Quilaia apresentou redução fúngica do biofilme principalmente nas duas maiores concentrações (100 mg/mL e 50 mg/mL) do extrato para ambos os tempos (5 min e 24 h) quando comparados com o grupo controle negativo que não recebeu tratamento, apresentando diferenças estatísticas significativas (p<0.001). A ação antibiofilme do extrato de Alcachofra apresentou reduções dos biofilmes significativas nas cinco concentrações (100 mg/mL, 50 mg/mL, 25 mg/mL, 12,5 mg/mL e 6,25 mg/mL) em ambos os tempos, na maioria das espécies, apresentando diferenças significativas (p<0.001). Diante disso, concluímos que os extratos glicólicos de Q. saponaria e C. scolymus apresentam ação antifúngica em todas as espécies de Candida spp. analisadas, sendo um potencial antifúngico para C. albicans e as espécies C. não-albicans, mas na espécie de C. krusei as reduções de biofilme só ocorrem nas maiores concentrações. Os resultados da ação antibiofilme manteve um padrão de ação, quanto maior a concentração do extrato, maior a redução, isto para ambos os extratos e para a maioria das espécies analisadas (AU)

Candida spp. They are the main human fungal pathogen and can cause superficial and invasive infections. The emergence of new species in infections, presenting high resistance to the antifungals used, challenges researchers to propose new therapies to control this infection, among which we can mention phytotherapy using plant extracts to propose new protocols. Therefore, this work aims to evaluate the antifungal action of extracts isolated from Quilaia (Quillaja saponaria) and Artichoke (Cynara scolymus) on C. albicans, C. glabrata, C. krusei, C. tropicalis and C. dubliniensis in planktonic forms and biofilms monotypic. Initially, analyzes of the antifungal action of Quilaia and Artichoke extracts were carried out using the broth microdilution test (CLSI ­ Protocol M27-S4), to determine the Minimum Inhibitory Concentrations (MICs) and Minimum Fungicide Concentrations (MFCs) of species. Biofilms were formed for 48 h in microplate wells, which received extract concentration treatments (100 mg/mL, 50 mg/mL, 25 mg/mL, 12.5 mg/mL and 6.25 mg/mL), as well as the positive and negative control groups were tested to determine cell viability using the MTT test. The data were statistically analyzed using the ANOVA and Tukey tests, with a significance of 5%. The MIC and CFM results for the species C. albicans, C. krusei and C. glabrata were 12.5 mg/mL for both extracts, the values for C tropicalis were 12.5 mg/mL for the Quilaia extract and 25 mg/mL for Artichoke, both extracts presented the same value of 6.25 mg/mL for the species C. dubliniensis. The antibiofilm action of the Quilaia extract showed a fungal reduction of the biofilm mainly at the two highest concentrations (100 mg/mL and 50 mg/mL) of the extract for both times (5 min and 24 h) when compared with the negative control group that did not receive treatment, showing significant statistical differences (p<0.001). The antibiofilm action of Artichoke extract showed significant reductions in biofilms at the five concentrations (100 mg/mL, 50 mg/mL, 25 mg/mL, 12.5 mg/mL and 6.25 mg/mL) at both times, in most species, showing significant differences (p<0.001). Therefore, we conclude that glycolic extracts of Q. saponaria and C. scolymus have antifungal action on all species of Candida spp. analyzed, with antifungal potential for C. albicans and non-albicans C. species, but in the C. krusei species, biofilm reductions only occur at higher concentrations. The results of the antibiofilm action maintained a pattern of action, the higher the concentration of the extract, the greater the reduction, this for both extracts and for the majority of species analyzed(AU)

Atividade antifúngica de nanofibras de policaprolactona/nistatina: estudo in vitro e in vivo / Antifungal activity of polycaprolactone/nystatin nanofibers: in vitro and in vivo study

Este estudo avaliou a eficácia in vitro e in vivo de mantas de nanofibras (NF) de policaprolactona (PCL) incorporadas com nistatina (NIS) no tratamento da estomatite protética (EP) em modelos animais. NF foram sintetizadas com diferentes concentrações de NIS, totalizando quatro soluções: PCL puro, PCL/NIS 0,045 g, PCL/NIS 0,090 g e PCL/NIS 0,225 g. A liberação da NIS foi analisada por espectroscopia Ultravioleta-Visível. A capacidade das mantas de inibirem o biofilme de Candida albicans, principal fator etiológico da EP, dividindo-se cinco grupos (N=5) compostos por um grupo com controle de células de C. albicans e com PCL puro, além das três concentrações de NIS. A seguir, foi analisada a viabilidade celular em queratinócitos humanos (HaCat) por meio do teste colorimétrico de resazurina. Cinco grupos foram divididos (N=10): controle celular, PCL puro e as três concentrações de NIS. Em modelos animais de ratos Wistar albinos (N=18), dispositivos palatinos (DP) de resina acrílica foram confeccionados simulando próteses totais e utilizados para a indução da EP. Para isso, DP contaminados com C. albicans foram cimentados na região molar da cavidade bucal dos animais e permaneceram em boca por 48 h. Após esse período, os DP foram removidos e os animais foram divididos em três grupos: (C) controle; (B1) com tratamento por mantas de PCL/NIS 0,045 g e (B2) PCL/NIS 0,225 g, com N=6. Então novos DP, livres de contaminação, foram cimentados na cavidade oral dos animais e permaneceu por mais 48 h. Após esse período, os animais foram eutanasiados, a contagem de UFC/ mL foi realizada e os palatos foram coletados para a análise histológica. A curva padrão de NIS obtida apresentou R2 de 0,99. As três concentrações de NF apresentaram liberação de NIS, com pico no tempo de 6 h e valores de 66,26 µg/ mL para PCL/NIS 0,045 g, de 333,87 µg/ mL para PCL/NIS 0,090 g e 436,51 µg/ mL para PCL/NIS 0,225 g, constantes até o fim do experimento. Os grupos com NIS reduziram em 2,5 log10 de crescimento do biofilme fúngico em relação aos grupos sem tratamento, Controle e PCL, sem diferença estatística significativa. Não foi observada citotoxicidade nas células HaCat, com viabilidade celular de 93,7% para PCL/NIS 0,045 g, 72,6% para PCL/NIS 0,090 g e 72,4% para PCL/NIS 0,225 g. A indução da EP nos três grupos foi possível e, porém, sem redução significativa na contagem de UFC/ mL de C. albicans nos grupos B1 e B2. Na análise histológica do grupo C pôde-se observar infiltração de hifas de Candida na camada queratinizada, presença de células inflamatórias formando micro abscessos e um discreto infiltrado inflamatório no tecido conjuntivo subjacente ao epitélio infectado. Nos grupos B1 e B2 não foram encontradas alterações epiteliais, concluindo-se que as NF demonstraram atividade antifúngica in vitro e foram efetivas na prevenção da penetração de hifas no tecido palatino de animais com DP (AU)

This study evaluated the in vitro and in vivo efficacy of nanofiber (NF) mats of polycaprolactone (PCL) incorporated with nystatin (NIS) in the treatment of denture stomatitis (DS) in animal models. NFs were synthesized with different concentrations of NIS, totaling four solutions: pure PCL, PCL/NIS 0.045 g, PCL/NIS 0.090 g, and PCL/NIS 0.225 g. The release of NIS was analyzed by Ultraviolet-Visible spectroscopy. The ability of the mats to inhibit Candida albicans biofilm, the main etiological factor of DS, was assessed by dividing five groups (N=5) composed of a group with C. albicans cell control and with pure PCL, in addition to the three concentrations of NIS. Next, cell viability in human keratinocytes (HaCat) was analyzed using the resazurin colorimetric test. Five groups were divided (N=10): cell control, pure PCL, and the three concentrations of NIS. In albino Wistar rat animal models (N=18), palatal devices (PD) made of acrylic resin were fabricated to simulate total prostheses and used to induce DS. For this, PD contaminated with C. albicans were cemented in the molar region of the animals' oral cavity and remained in the mouth for 48 hours. After this period, the PDs were removed, and the animals were divided into three groups: (C) control; (B1) treated with PCL/NIS 0.045 g mats, and (B2) PCL/NIS 0.225 g, with N=6. Then new, uncontaminated PDs were cemented in the animals' oral cavity and remained for another 48 hours. After this period, the animals were euthanized, UFC/ mL counts were performed, and the palates were collected for histological analysis. The standard NIS curve obtained showed an R2 of 0.99. The three concentrations of NF showed NIS release, with a peak at 6 h and values of 66.26 µg/ mL for PCL/NIS 0.045 g, 333.87 µg/ mL for PCL/NIS 0.090 g, and 436.51 µg/ mL for PCL/NIS 0.225 g, remaining constant until the end of the experiment. The groups with NIS reduced fungal biofilm growth by 2.5 log10 compared to the untreated groups, Control and PCL, with no significant statistical difference. No cytotoxicity was observed in HaCat cells, with cell viability of 93.7% for PCL/NIS 0.045 g, 72.6% for PCL/NIS 0.090 g, and 72.4% for PCL/NIS 0.225 g. Induction of DS in the three groups was possible; however, there was no significant reduction in UFC/ mL counts of C. albicans in groups B1 and B2. Histological analysis of group C revealed infiltration of Candida hyphae in the keratinized layer, presence of inflammatory cells forming micro abscesses, and a discreet inflammatory infiltrate in the connective tissue underlying the infected epithelium. No epithelial alterations were found in groups B1 and B2, concluding that NFs demonstrated in vitro antifungal activity and were effective in preventing hyphal penetration into palatal tissue in animals with PD.(AU)

Comparative in vitro analysis of the antifungal activity of different calcium silicate-based endodontic sealers

Aim: This study aimed to perform an in vitro comparative analysis of the antifungal activity of different calcium silicate-based endodontic sealers against three fungal species. Methods: The antifungal properties of three calcium silicate-based sealers were tested: Bio-C Sealer, Cambiar a Sealer Plus BC, and MTA-Fillapex. Two commonly used sealers were used as controls: AH Plus and Endomethasone. An agar diffusion test was performed to analyze the antifungal activity of the sealers against Candida albicans, Candida glabrata, Candida tropicalis, and a mixed microbial culture medium. The results were analyzed using ANOVA (p <0.05). Results: Endomethasone exhibited the highest inhibition against all strains examined, maintaining a consistent level of inhibition throughout 7 days. MTA-Fillapex demonstrated the best performance among the calcium silicate-based sealers for the three fungal species (p < 0.05), maintaining stable values over the 7 days, surpassing that of Endomethasone. Nevertheless, MTA-Fillapex only exhibited antimicrobial effect against the mixed culture for the first 24 hours, and no antimicrobial activity was observed at 48 hours, being surpassed by all tested sealers (p < 0.05). Conclusion: Of all silicate-based sealers tested, only MTA-Fillapex exhibited promising antifungal activity. Nevertheless, care must be taken when extrapolating these results, as MTA-Fillapex exhibited poor antimicrobial activity when tested in mixed microbial cultures

Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp

Abstract In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

Resumo No atual contexto de patógenos fúngicos resistentes emergentes tais como Candida albicans e Candida parapsilosis, a descoberta de novos agentes antifúngicos é uma questão urgente. Esta pesquisa teve como objetivo avaliar o potencial antifúngico da 2-cloro-N-fenilacetamida contra cepas clínicas de C. albicans e C. parapsilosis resistentes a fluconazol. A atividade antifúngica da substância foi avaliada in vitro através da determinação da concentração inibitória mínima (CIM), concentração fungicida mínima (CFM), ruptura e inibição da formação de biofilme, ensaios de sorbitol e ergosterol, e associação entre esta molécula e antifúngicos comuns, anfotericina B e fluconazol. O produto teste inibiu todas as cepas de C. albicans e C. parapsilosis, com uma CIM variando de 128 a 256 µg.mL-1, e uma CFM de 512-1,024 µg.mL-1. Também inibiu até 92% da formação de biofilme e causou a ruptura de até 87% de biofilme pré-formado. A 2-cloro-N-fenilacetamida não promoveu atividade antifúngica pela ligação ao ergosterol da membrana celular fúngica, tampouco danificou a parede celular. Antagonismo foi observado ao combinar esta substância com anfotericina B e fluconazol. A substância exibiu atividade antifúngica significativa ao inibir tanto as células planctônicas quanto o biofilme das cepas resistentes ao fluconazol. Sua combinação com outros antifúngicos deve ser evitada e seu mecanismo de ação deve ser estabelecido.

Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp / Atividade antifúngica de 2-cloro-N-fenilacetamida: uma nova molécula com atividade fungicida e anti-biofilme contra Candida spp. resistentes a fluconazol

In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

No atual contexto de patógenos fúngicos resistentes emergentes tais como Candida albicans e Candida parapsilosis, a descoberta de novos agentes antifúngicos é uma questão urgente. Esta pesquisa teve como objetivo avaliar o potencial antifúngico da 2-cloro-N-fenilacetamida contra cepas clínicas de C. albicans e C. parapsilosis resistentes a fluconazol. A atividade antifúngica da substância foi avaliada in vitro através da determinação da concentração inibitória mínima (CIM), concentração fungicida mínima (CFM), ruptura e inibição da formação de biofilme, ensaios de sorbitol e ergosterol, e associação entre esta molécula e antifúngicos comuns, anfotericina B e fluconazol. O produto teste inibiu todas as cepas de C. albicans e C. parapsilosis, com uma CIM variando de 128 a 256 µg.mL-1, e uma CFM de 512-1,024 µg.mL-1. Também inibiu até 92% da formação de biofilme e causou a ruptura de até 87% de biofilme pré-formado. A 2-cloro-N-fenilacetamida não promoveu atividade antifúngica pela ligação ao ergosterol da membrana celular fúngica, tampouco danificou a parede celular. Antagonismo foi observado ao combinar esta substância com anfotericina B e fluconazol. A substância exibiu atividade antifúngica significativa ao inibir tanto as células planctônicas quanto o biofilme das cepas resistentes ao fluconazol. Sua combinação com outros antifúngicos deve ser evitada e seu mecanismo de ação deve ser estabelecido.

Efeitos dos líquidos ativados com plasma atmosférico sobre Candida albicans / Application of plasma activated liquids on Candida albicans

O incremento no número de casos refratários aos tratamentos convencionais e a limitação de opções terapêuticas são alguns dos desafios encontrados no tratamento da candidose bucal, apontando para a necessidade de terapias alternativas. A utilização da tecnologia de plasma de forma indireta, pela exposição prévia de líquidos ex situ, tem mostrado resultados promissores, trazendo inúmeras vantagens para a aplicação clínica. Até o momento, pouco se conhece sobre a atividade antifúngica do líquido ativado com plasma (LAP) e não foram detectados relatos sobre sua aplicabilidade no tratamento da candidose bucal. Com base neste cenário, o objetivo deste projeto foi avaliar a atividade do líquido ativado com plasma sobre Candida albicans, principal agente etiológico da candidose bucal. Para tanto, foram determinadas as condições de obtenção do LAP com maior efeito antifúngico frente a C. albicans. O LAP foi gerado em um reator de plasma tipo arco deslizante (gliding arc). Os gases empregados incluíram argônio, ar comprimido seco e suas misturas em diversas concentrações, ajustando-se o fluxo de gás e a potência conforme necessário. Avaliou-se a eficácia antifúngica de diferentes líquidos ativados contra C. albicans, tanto em estado planctônico quanto em biofilmes, visando identificar o mais efetivo. As espécies reativas dos LAP foram caracterizadas utilizando técnicas espectrofotométricas, juntamente com a avaliação dos parâmetros físico-químicos. Os resultados dos ensaios foram submetidos a análise estatística, estabelecendo-se um nível de significância de 5% para a interpretação dos dados. Observou-se que a solução salina 0,9% ativada com plasma de argônio (S1), água destilada ativada com plasma de argônio (D1) e água destilada ativado com a mistura dos gases argônio e ar comprimido (S2) apresentaram a maior atividade antifúngica sobre células planctônicas de C. albicans quando expostas por 30 minutos ao LAP. O grupo D1 apresentou maior ação frente aos biofilmes de 24 e 48 horas e o S1 frente a biofilmes de 48 horas apenas quando exposto por 30 minutos ao LAP. Ambos os LAPs apresentaram ação antifúngica após terem sido congelados e armazenados por 1 dia após a ativação. Os grupos D1 e S1 não apresentaram perfil citotóxico nos ensaios realizados. Pode-se concluir que os LAPs apresentaram ação inibitória sobre células planctônicas e sobre biofilmes de C. albicans, sem citotoxicidade para células de mamíferos, sugerindo seu potencial como adjuvante às terapias para o controle da candidose.(AU)

The increase in the number of cases refractory to conventional treatments and the limitation of therapeutic options is due to some two challenges encountered in the treatment of oral candidiasis, pointing to the need for alternative therapies. The use of plasma technology indirectly, for the exposition of liquids ex situ, has shown promising results, providing numerous advantages for clinical application. Currently, little is known about the antifungal activity of plasma-activated liquid (LAP) and there are no reports on its applicability in oral candidiasis treatment. Based on this scenario, the objective of this project is to validate the application of plasma-activated liquid as an adjuvant in the treatment of oral candidiasis. Therefore, certain conditions for obtaining LAP have greater antifungal effect against Candida albicans. The LAP was generated in a gliding arc type plasma reactor. The gases used include argon, dry compressed and their mixtures in various concentrations, adjusting the gas flow and power as necessary. The antifungal efficacy of different liquids activated against C. albicans is evaluated, both in the planktonic state and in biofilms, aiming to identify the most effective. The relative species of LAP were characterized using spectrophotometric techniques, together with the evaluation of two physical-chemical parameters. The results of two tests were submitted to statistical analysis, establishing a significance level of 5% for the interpretation of the data. It was observed that the groups that presented the greatest antifungal activity in planktonic cells of C. albicans were the groups of 0.9% saline solution activated with argonium plasma (S1), or of distilled water activated with argonium plasma (D1). e or distilled water activated with a mixture of two argon gases and compressed air (S2). The D1 group presented against biofilms of 24 and 48 hours and the S1 against biofilms of only 48 hours. Both LAPs are presented with antifungal coating and have been frozen and stored for 1 day after activation. The groups D1 and S1 do not present a cytotoxic profile in the tests carried out. It can be concluded that the LAPs have antifungal activity on planktonic cells and on biofilms and do not present a toxicity profile for human cells, being potent adjuvants in therapies for or controlling infections caused by C. albicans (AU)

Evaluación in vitro de la actividad antifúngica de extractos fluidos de Dichrostachys cinerea L. (marabú) frente a Candida albicans

Introducción: La Dichrostachys cinerea L. (marabú) es una planta que crece en Cuba, de la que se estudian propiedades medicinales. La resistencia de levaduras del género Candida a los antifúngicos sintéticos disponibles en la actualidad es cada vez mayor, por lo que se buscan nuevos compuestos de origen vegetal que puedan ser eficaces en el tratamiento de infecciones causadas por este germen. Objetivo: Evaluar la actividad antifúngica in vitro de Dichrostachys cinerea L. contra una cepa de Candida albicans. Métodos: Se realizó un estudio observacional analítico transversal in vitro para evaluar la actividad antifúngica de extractos fluidos de hojas y de tallos de D. cinerea L mediante el método de macrodilución en caldo y como sustancia de referencia el alcohol. Resultados: A través del proceso se mostró la actividad antifúngica del extracto fluido de tallos de D. cinerea L. al 50 % hasta la dilución 1/32, determinada como la concentración mínima inhibitoria; el extracto fluido de hojas al 30 % no logró inhibir el crecimiento de la cepa de Candida albicans ATCC 10231. Conclusiones: La actividad antifúngica del extracto fluido al 50 % de las hojas de Dichrostachys cinerea L. fue efectiva, no así el preparado farmacéutico al 30 %. Se determinó la concentración mínima inhibitoria del extracto fluido de hojas al 50 % y se demostró que ésta superó a la del alcohol al 50 % en tres diluciones contra la Candida albicans.

Introduction: Dichrostachys cinerea L. (marabou) is a plant that grows in Cuba, medicinal properties of this plant are being studied. The resistance of yeasts of the Candida genus to current available synthetic antifungals is increasingly greater. This is why, new compounds of plant origin are being searched for the effective treatment of infections caused by this germ. Objective: To evaluate the in vitro antifungal activity of Dichrostachys cinerea L against a strain of Candida albicans. Methods: An in vitro a cross-sectional analytic observational study was carried out to evaluate the antifungal activity of fluid extracts of D. cinerea L leaves and stems using the broth macro-dilution method and alcohol as the reference substance. Results: Through the process was shown the antifungal activity of the fluid extract of Dichrostachys cinerea L. stems at 50% up to the 1/32 dilution; it was determined as the minimum inhibitory concentration. The leaves fluid extract at 30% failed to inhibit the growth of the Candida albicans ATCC 10231 strain. Conclusions: The antifungal activity of the fluid extract at 50% of the leaves was effective, but not the pharmaceutical preparation at 30%. The minimum inhibitory concentration of the fluid extract of leaves at 50% was determined and it was shown that it exceeded that of alcohol at 50% in three dilutions against Candida albicans.

Oral candidiasis in liver transplant patients: species identification and antifungal susceptibility profile

ABSTRACT Objective This study aimed to verify oral candidiasis, identify the causative species, and investigate the antifungal susceptibility of yeasts isolated from liver transplant patients. Methods A descriptive analysis of 97 patients who underwent liver transplantation was conducted at a hospital. Two clinical examinations (Collections A and B) of the oral cavity were performed. Oral material was collected from all patients, inoculated in Sabouraud Dextrose Agar, and incubated at 35℃ for 48 hours. Samples were identified by molecular sequencing of the internal trascribed space region of rDNA. Results An antifungal susceptibility test with fluconazole, amphotericin B, and micafungin was performed using the Clinical and Laboratory Standards Institute yeast broth microdilution method. Among the patients, 15 presented with oral candidiasis: eight in Collection A and seven in Collection B. The primary type of candidiasis was atrophic, followed by pseudomembranous candidiasis. The most prevalent species was Candida albicans (nine), followed by Candida glabrata (three), Candida tropicalis (two), and Candida dubliniensis (one). Regarding susceptibility to fluconazole, of the 15 samples, 11 were susceptible, three were susceptible in a dose-dependent manner, and one was resistant. Conclusion The most commonly identified type of candidiasis was atrophic, with C. albicans and C. glabrata being the most prevalent causative species. One fluconazole-resistant isolate each of C. tropicalis and C. albicans were identified.

Colangitis aguda por Candida glabrata y Klebsiella pneumoniae / Acute cholangitis due to Candida glabrata and Kleb siella pneumoniae

Resumen La colangitis aguda es una infección de la vía biliar, asociada a la obstrucción de esta. El cultivo de la bilis es positivo en la mayoría de los casos y el agente etio lógico más frecuente es Escherichia coli. La colangitis aguda por Candida sp es un hallazgo poco común, que es más frecuente en pacientes con inmunocompromiso, uso de corticoides, tratamiento antibiótico prolongado o procedimientos quirúrgicos de la vía biliar. Presenta mos el caso de una mujer de 67 años, que no presen taba ninguno de los antecedentes mencionados, y que consultó por fiebre, dolor abdominal e ictericia. En la resonancia magnética nuclear de abdomen se constató imagen litiásica en el colédoco con dilatación de la vía biliar. Requirió drenaje endoscópico del tracto biliar. En el examen microscópico directo del líquido biliar se evidenciaron levaduras y bacilos Gram negativos, y en el cultivo se aisló Klebsiella pneumoniae productora de betalactamasa de espectro extendido (BLEE) y Candida glabrata. La paciente completó el tratamiento antibiótico con piperacilina tazobactam y anidulafungina con buena evolución. La infección de la vía biliar por la asociación de bacilos Gram negativos y Candida sp es una entidad poco frecuente, más en pacientes sin enfermedades subyacentes.

Abstract Acute cholangitis is a bile duct infection associated with bile duct obstruction. Bile culture is positive in most cases, and the most frequent etiological agent is Escherichia coli. Candida sp acute cholangitis is a rare finding, which is more common in patients with im munosuppression, use of corticosteroids, prolonged antibiotic treatment or surgical procedures of the bile duct. We present the case of a 67-year-old woman with none of the above-mentioned history who consulted for fever, abdominal pain and jaundice. MRI of the ab domen revealed a lithiasic image in the common bile duct with dilation. It required endoscopic drainage of the biliary tract. Direct microscopic examination of the bile fluid revealed gram-negative bacilli and yeast, and in the culture of bile fluid Klebsiella pneumoniae produc ing extended spectrum beta-lactamase (ESBL) and Can dida glabrata were isolated. The patient completed the antibiotic treatment with piperacillin tazobactam and anidulafungin with good evolution. Bile duct infection by association of Gram-negative bacilli and Candida sp is a rare entity, more in patients without underlying diseases.

Efeito de extratos vegetais de Hamamelis virginiana, Persea americana, Cynara scolymus L e Stryphnodendron barbatiman Msobre a expressão fenotípica dos fatores de virulência em biofilmes de Candida albicans / Effect of Hamamelis virginiana, Persea americana, Cynara scolymus L and Stryphnodendron barbatiman M plant extracts on the phenotypic expression of virulence factors in biofilms of the Candida albicans

Objetivo: Analisar a expressão fenotípica de fatores de virulência em biofilmes de Candida albicans frente a extratos glicólicos de plantas. Material e Métodos: Os biofilmes de Candida albicans (ATCC 18804) obtidos a partir de incubação de 48 horas foram expostos por 5 minutos e 24 horas a diferentes concentrações de extratos glicólicos de Hamamelis virginiana e Persea americana, Cynara scolymus L e Stryphnodendron barbatiman M, a fim de verificar a ação antifúngica da proteinase, fosfolipase e hemolisina. Resultados: Todos os extratos foram eficazes na redução do biofilme. Em contato por 5 minutos. os extratos reduziram 50% do biofilme. Após 24 horas. o extrato de Persea americana apresentou o biofilme em 90%, seguido de Cynara scolymus, que o interrompeu em 85%. Houve mudança na intensidade da proteinase após 5 minutos e 24 horas, com uma atividade enzimática média de 0,69 em comparação com o controle de 0,49. Cynara scolymus foi o extrato com maior concentração média de 100 mg/ml; a intensidade da fosfolipase foi alterada com Stryphnodendron barbatiman sendo mais efetivo em 24 horas em relação ao controle (p< 0,0001). A secreção de hemolisina foi modificada por Hamamelis virginiana (12,5 mg/ml) após 5 minutos de exposição e em 24 horas. todos os extratos foram capazes de causar alterações na secreção. Conclusão: Os extratos testados apresentam potencial antifúngico em biofilmes de Candida albicans, implicando em redução significativa dos fatores de virulência. Assim, estes podem ser indicados como uma ferramenta terapêutica alternativa para reduzir a morbidade dessas infecções, já que em ambos os tempos de exposição investigados, eles foram capazes de reduzir a secreção enzimática do fungo (AU)

Objective: Analyze the phenotypic expression of virulence factors in Candida albicans biofilms against plant glycolicextracts. Material and Methods: The biofilms of Candida albicans (ATCC 18804) obtained from incubation for 48 hours were exposed for 5 minutes and 24 hours to different concentrations of glycolic extracts of Hamamelis virginiana and Persea americana, Cynara scolymus L and Stryphnodendron barbatiman M, in order to verify the antifungal activity of the proteinase, phospholipase and hemolysin. Results: All extracts were effective in reducing biofilm. In contact for 5 minutes. the extracts reduced 50% of the biofilm. After 24 hours, the Persea americanaextract showed the biofilm at 90%, followed by Cynara scolymus, which interrupted it at 85%, There was a change in proteinase intensity after 5 minutes and 24 hours. with an average enzymatic activity of 0.69 compared to the control of 0.49. Cynara scolymus was the extract with the highest mean concentration of 100 mg/ml; the phospholipase intensity was changed with Stryphnodendron barbatiman being more effective in 24 hours compared to the control (p< 0.0001). The hemolysin secretion was modified by Hamamelis virginiana (12.5 mg/ml) after 5 minutes of exposure, and in 24 hours. all extracts were capable to cause changes in secretion. Conclusion: The tested extracts have antifungal potential in Candida albicans biofilms, implying a significant reduction in virulence factors. Thus, these can be indicated as an alternative therapeutic tool to reduce the morbidity of these infections, as in both investigated exposure times. they were able to reduce theenzymatic secretion of the fungus (AU)

Phylogenetic diversity and susceptibility of Candida species from women using contraceptive devices in northcentral Nigeria

Background: The use of contraceptive devices predisposes women to vulvovaginal candidiasis (VVC) globally. Despite the high incidence of VVC and antifungal resistance to azoles, the genetic diversity and resistance pattern among contraceptive users in Nigeria is poorly investigated. This study therefore sought to characterize and determine the phylogenetic breadth of Candida species as well as their resistance to antifungal agents. Methodology: This study recruited 1,600 women using contraceptive devices who visited selected gynaecology and obstetrics clinics in northcentral Nigeria. Candida species were isolated and characterized using conventional methods and sequencing of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA). Bayesian phylogenetic analysis was used to characterize the diversity of Candida species and primer-specific PCR was used to detect the presence of resistant genes. Agar well diffusion technique was used for the determination of antifungal susceptibility profiles. Data analysis was done by Kruskal-Wallis Chi-square test on R Console software version 3.2.2, followed by post-hoc Wilcoxon rank sum test with Bonferroni correction for multiple pairwise comparisons of means where there was a significant difference between the antifungal agents. The level of significance was set at p < 0.05. Results: A total of 710 (44.3%) out of the 1,600 women using contraceptive devices had VVC with five species of Candida identified in them. Although Candida albicans was the predominant (43.2%, n=307) species, other non-albicans Candida species include Candida (Nakaseomyces) glabrata (19.0%, n=135), Candida tropicalis (15.8%, n=112), Candida parapsilosis (8.9%, n=63), and Candida akabanensis (13.1%, n=93) which were phenotypically identified as Candida (Nakaseomyces) glabrata. All the Candida species showed varying degrees of susceptibilities to voriconazole, fluconazole and nystatin. However, resistance of C. albicans to fluconazole was 29.0%, C. tropicalis to nystatin (46.0%) and to voriconazole (14.0%), while C. akabanensis was 100.0% resistant to voriconazole and fluconazole. Kruskal-Wallis Chi-square test showed nystatin as the most effective antifungal agent against the Candida species (χ2=786.03, df=2, p<0.001). Also, resistant gene Erg11 was identified in all the Candida species that were phenotypically resistant to the antifungal agents tested. Conclusion: Women using contraceptive devices in northcentral Nigeria harbor phylogenetically diverse Candida species including C. akabanensis, an uncommon cause of VVC. Of these Candida species, C. albicans, C. tropicalis and C. akabanensis were notable for multidrug drug resistance as well as harboring Erg11 resistance gene.

Impact on the clinical evolution of patients with COVID-19 from an Intensive Care Unit with isolation of Candida spp. in respiratory samples / Impacto na evolução clínica de pacientes com COVID-19 de uma Unidade de Terapia Intensiva com isolamento de Candida spp. em amostras respiratórias / Impacto en la evolución clínica de pacientes con COVID-19 de una Unidad de Cuidados Intensivos con aislamiento de Candida spp. en muestras respiratorias

Background and Objectives: several patients with COVID-19 require hospital admission due to severe respiratory complications and undergo intensive care with mechanical ventilation (MV) support. Associated with this situation, there is an increase in fungal co-infections, which has a negative impact on the outcome of COVID-19. In this regard, this study intended to compare Candida spp. incidence in the respiratory tract of patients admitted in the COVID and General Intensive Care Units (ICU) at a teaching hospital in 2021. Methods: the results of protected tracheal aspirate samples from 556 patients admitted to the COVID ICU and 260 to General ICU as well as the respective records. Results: of the patients analyzed, 38 revealed a positive sample for Candida in the COVID ICU and 10 in the General ICU, with an incidence of 68.3/1000 and 38.5/1000, respectively. Males were predominant in both wards. The most affected age group was the population over 60 years old, and the average hospital admission for the COVID ICU was 22.1 years, and for the General ICU, 24.2. Conclusion: Candida albicans was the most frequently isolated species, and the mortality rate in patients positive for Candida was higher in patients with COVID-19 compared to patients in the General ICU, suggesting that patients infected with SARS-CoV-2, admitted to the ICU under MV, are more predisposed to colonization by Candida spp., which can have a fatal outcome in these patients.(AU)

Justificativa e objetivos: muitos pacientes com COVID-19 necessitam de hospitalização devido às complicações respiratórias graves, e são submetidos a cuidados intensivos com suporte de ventilação mecânica (VM). Associado a esse quadro, verifica-se o aumento de coinfecções fúngicas, que tem impacto negativo no desfecho da COVID-19. Nesse sentido, este estudo pretendeu comparar a incidência de Candida spp. no trato respiratório de pacientes internados nas Unidades de Terapia Intensiva (UTI) COVID e Geral em um hospital escola em 2021. Métodos: foram avaliados os resultados de amostras de aspirado traqueal protegido provenientes de 556 pacientes internados na UTI COVID e 260 na UTI Geral, bem como os respectivos prontuários. Resultados: dos pacientes analisados, 38 revelaram amostra positiva para Candida na UTI COVID e 10 na UTI Geral, com incidência de 68,3/1000 e 38,5/1000, respectivamente. O sexo masculino foi predominante em ambas as alas. A faixa etária mais acometida foi a população acima de 60 anos, e a média de internação para a UTI COVID foi de 22,1 anos, e para a UTI Geral, 24,2. Conclusão: Candida albicans foi a espécie isolada com maior frequência, e a taxa de mortalidade em pacientes com positivos para Candida foi maior em pacientes com COVID-19 em relação aos pacientes da UTI Geral, sugerindo que pacientes infectados com SARS-CoV-2, internados em UTI sob VM, são mais predispostos à colonização por Candida spp., que pode ter um desfecho fatal nesses pacientes.(AU)

Justificación y objetivos: muchos pacientes con COVID-19 requieren hospitalización debido a complicaciones respiratorias graves y se someten a cuidados intensivos con soporte de ventilación mecánica (VM). Asociado a esta situación, hay un aumento de las coinfecciones fúngicas, lo que repercute negativamente en el desenlace de la COVID-19. En este sentido, este estudio pretendió comparar la incidencia de Candida spp. en el tracto respiratorio de pacientes ingresados en las Unidades de Cuidados Intensivos (UCI) COVID y General de un hospital escuela en 2021. Métodos: los resultados de muestras de aspirado traqueal protegidas de 556 pacientes ingresados en la UCI COVID y 260 en el UCI General, así como los respectivos registros. Resultados: de los pacientes analizados, 38 presentaron muestra positiva a Candida en UCI COVID y 10 en UCI General, con una incidencia de 68,3/1000 y 38,5/1000, respectivamente. Los machos predominaban en ambas alas. El grupo de edad más afectado fue la población mayor de 60 años, y la hospitalización promedio en la UCI COVID fue de 22,1 años, y en la UCI General, de 24,2. Conclusiones: Candida albicans fue la especie aislada con mayor frecuencia, y la tasa de mortalidad en pacientes positivos para Candida fue mayor en pacientes con COVID-19 en comparación con los pacientes en la UCI General, lo que sugiere que los pacientes infectados con SARS-CoV-2, ingresados en la UCI bajo VM, están más predispuestos a la colonización por Candida spp., lo que puede tener un desenlace fatal en estos pacientes.(AU)

Abscesos renales bilaterales multifocales por Candida albicans / Bilateral multifocal kidney abscess due to Candida al bicans

Resumen Los abscesos renales son una complicación poco frecuente de las infecciones del tracto urinario y suelen asociarse con un aumento de la morbi-mortalidad. La mayoría de los casos ocurre en pacientes con factores predisponentes como la inmunosupresión. El diagnóstico requiere de una elevada sospecha clínica y el trata miento consiste en el uso de antibióticos y antifúngicos parenterales asociados o no a intervenciones quirúrgicas como nefrostomía y nefrectomía. Son pocos los casos publicados en la literatura médi ca de abscesos renales bilaterales multifocales y menos aún por Candida albicans. Se presenta el caso de una mujer de 20 años de edad con diabetes mellitus tipo 1 diagnosticada a los 8 años, múltiples internaciones por cetoacidosis diabética y reciente internación por can didemia (Candida albicans) completando tratamiento con fluconazol por 23 días. A los 18 días de su externación, consulta por dolor en flancos de tipo sordo y síntomas ge nerales; se realizó tomografía de abdomen con contraste que mostró abscesos multifocales bilaterales. Aislándose Candida albicans en una de las muestras obtenidas de las lesiones; recibió tratamiento con fluconazol 400 mg por 6 semanas endovenoso y 2 semanas vía enteral, evolu cionando favorablemente con mejoría clínica e image nológica continuando seguimiento clínico ambulatorio. Este reporte resalta la importancia del diagnóstico y tratamiento de esta complicación infrecuente en enfer medades complejas como la diabetes.

Abstract Renal abscesses are a rare complication of urinary tract infections and may be associated with increased morbidity and mortality. Most cases occur in patients with predisposing factors such as immunosuppression. Diagnosis requires high clinical suspicion and its treat ment consists in the use of parenteral antibiotics and antifungals associated or not with surgical interventions such as nephrostomy and nephrectomy. Few cases have been published in the medical literature of multifocal bilateral renal abscesses and even fewer due to Candida albicans. We present the case of a 20-year-old woman with type 1 diabetes mellitus, diagnosed at age 8, multiple hospitalizations for diabetic ketoacidosis, and recent hospitalization for candidemia (Candida albicans) treated with fluconazole for 23 days. Eighteen days after her discharge, she consulted for dull flank pain and gen eral symptoms. Contrast enhanced abdominal tomography showed bilateral multifocal abscesses and Candida albicans was isolated in one of the samples obtained from lesions. She received fluconazole 400 mg, 6 weeks i.v. and 2 weeks via enteral route, evolving favorably with clinical and imag ing improvement, continuing outpatient clinical monitoring. This report highlights the importance of diagnosis and treatment of this rare complication in complex diseases such as diabetes mellitus.

Candida parapsilosis endocarditis without vegetations at Echocardiography: a case report / Endocarditis por Candida parapsilosis sin vegetaciones ecocardiográficas: Un reporte de caso

ABSTRACT Candida endocarditis is a very serious manifestation of candida infections, and it has increased in incidence over the past years. Of these, C. parapsilosis has been described as a cause of endocarditis in native valves of intravenous drug users and prosthetic valves. We report the case of a female that developed a cerebrovascular accident secondary to emboli from aortic prosthetic valve C. parapsilosis endocarditis, despite apparently normal echocardiography. She received antifungal therapy without surgical intervention.

RESUMEN La endocarditis por Candida spp. es una manifestación muy grave de las infecciones por este patógeno y su incidencia ha ido aumentando en los últimos años. La Candida parapsilosis se ha descrito como causa de endocarditis en válvulas nativas de usuarios de drogas intravenosas y prótesis valvulares. Presentamos el caso de una mujer que desarrolló un accidente cerebrovascular secundario a émbolos fúngicos procedentes de una prótesis valvular aórtica infectada por C. parapsilosis, a pesar de un ecocardiograma sin vegetaciones. La paciente recibió tratamiento antifúngico sin necesidad de intervención quirúrgica.

gDNA extraction from Candida albicans and Candida dubliniensis in subgingival samples in Argentina. Evaluation of different methods / Evaluación de diferentes métodos de extracción de gADN en Candida albicans y Candida dubliniensis en muestras subgingivales en Argentina

ABSTRACT The oral cavity constitutes a unique ecosystem with highly variable ecological niches that harbor a great variety of microorganisms, including yeasts. Molecular methods are currently considered the gold standard for identifying species, although they involve limitations associated with the disruption of yeast cell walls to release the genomic DNA (gDNA) for amplification. Aim: The aim of this study was to compare the performance of different methods for extracting gDNA from Candida albicans and Candida dubliniensis, subsequently amplifying DNA by PCR. Materials and Method: Fifty-two isolates (16 C. albicans and 36 C. dubliniensis) were obtained from subgingival biofilm of HIV+ patients with clinical signs of periodontal disease. The study evaluated 6 gDNA extraction methods and two PCR amplification methods. Furthermore, the presence of alleles of HWP1 gene was determined in C. albicans. Results: Comparisons of six methods show statistically significant differences (p<0.001) except for C. albicans in two of them. For C. dubliniensis, statistical differences were observed in all comparisons. Commercial methods were more efficient for concentrating gDNA than in-house methods, and both PCRs were effective. Ten heterozygous C. albicans isolates for this allele were positive for the HWP1-1 / HWP1-2 allele, one was homozygous for Wild Type HWP1-1 allele, and 5 were homozygous for novel/rare HWP1-2 allele. Conclusions: This study aims to provide simple, inexpensive strategies for phenotypic identification and molecular confirmation of Candida albicans and Candida dubliniensis for non-reference laboratories with low complexity and/or low budgets.

RESUMEN La cavidad oral constituye un ecosistema único con nichos ecológicos muy variables, capaz de albergar una gran variedad de microorganismos, incluidas las levaduras. Los métodos moleculares son considerados actualmente los métodos de identificación definitivos ya que a diferencia de los anteriores, nos brindan una correcta sensibilidad y especificidad. Sin embargo, existen limitaciones asociadas con la ruptura de las paredes celulares de estas levaduras para liberar el ADN genómico (gADN) necesario para la amplificación. Objetivo: El objetivo de este estudio fue comparar el rendimiento de diferentes métodos de extracción de gADN de Candida albicans y Candida dubliniensis, amplificando posteriormente por PCR. Materiales y Método: Se estudiaron 52 aislamientos, 16/52 de Candida albicans y 36/52 de Candida dubliniensis obtenidos de biofilm subgingival de pacientes VIH+ con signos clínicos de enfermedad periodontal. Se evaluaron seis métodos de extracción de gADN y la posterior amplificación se realizó por dos técnicas de PCR. Además en C. albicans se determinó la presencia de alelos para el gen HWP1. Resultados: Las comparaciones de seis métodos son estadísticamente significativas (p<0,001) excepto para C. albicans en dos de ellos. Para C. dubliniensis se observaron diferencias estadísticas en todas las comparaciones. Los métodos comerciales mostraron una mayor eficiencia en la concentración de gADN que los métodos caseros y ambos fueron efectivos en las dos PCR. 10 aislados de C. albicans resultaron positivos para el alelo HWP1-1/HWP1-2, siendo heterocigotos para este alelo. Solo un aislamiento fue homocigoto para el alelo HWP1-1 de tipo salvaje y 5 eran homocigotos para el alelo HWP1-2 nuevo/raro. Conclusiones: Este estudio tiene como objetivo proporcionar estrategias simples y económicas para la identificación fenotípica y confirmación molecular de Candida albicans y Candida dubliniensis para laboratorios de no referencia con baja complejidad y/o bajo presupuesto económico.

Expression of ERG11, ERG3, MDR1 and CDR1 genes in Candida tropicalis / Expresión de los genes ERG11, ERG3, MDR1 y CDR1 en Candida tropicalis

Introduction. Drug resistance to azoles is a growing problem in the Candida genus. Objective. To analyze molecularly the genes responsible for fluconazole resistance in Candida tropicalis strains. Materials and methods. Nineteen strains, with and without exposure to fluconazole, were selected for this study. The expression of MDR1, CDR1, ERG11, and ERG3 genes was analyzed in sensitive, dose-dependent sensitive, and resistant strains exposed to different concentrations of the antifungal drug. Results. MDR1, ERG11 and ERG3 genes were significantly overexpressed in the different sensitivity groups. CDR1 gene expression was not statistically significant among the studied groups. Seven of the eight fluconazole-resistant strains showed overexpression of one or more of the analyzed genes. In some dose-dependent sensitive strains, we found overexpression of CDR1, ERG11, and ERG3. Conclusion. The frequency of overexpression of ERG11 and ERG3 genes indicates that they are related to resistance. However, the finding of dose-dependent resistant/sensitive strains without overexpression of these genes suggests that they are not exclusive to this phenomenon. More basic research is needed to study other potentially involved genes in the resistance mechanism to fluconazole.

Introducción. La farmacorresistencia a los azoles es un problema creciente en el género Candida. Objetivo. Analizar molecularmente los genes responsables de la resistencia a fluconazol en cepas de Candida tropicalis. Materiales y métodos. Para este estudio, se seleccionaron 19 cepas, con exposición a fluconazol y sin ella. Se analizó la expresión de los genes MDR1, CDR1, ERG11 y ERG3 en cepas sensibles, sensibles dependiente de la dosis, y resistentes, previamente expuestas a diferentes concentraciones del fármaco antifúngico. Resultados. Se encontró que los genes MDR1, ERG11 y ERG3 estaban significativamente sobreexpresados en los diferentes grupos de sensibilidad. La expresión del gen CDR1 no fue estadísticamente significativa entre los grupos estudiados. Siete de las ocho cepas resistentes a fluconazol mostraron sobreexpresión de uno o más de los genes analizados. En algunas cepas sensibles dependientes de la dosis, se encontró sobreexpresión de CDR1, ERG11 y ERG3. Conclusión. La sobreexpresión de los genes ERG11 y ERG3 indica que están relacionados con la resistencia de las cepas de Candida. Sin embargo, el hallazgo de cepas resistentes o sensibles según la dosis, sin sobreexpresión de estos genes, sugiere que pueden existir otros genes involucrados en este fenómeno. Se necesitan más investigaciones básicas que contribuyan al estudio de otros genes potencialmente involucrados en el mecanismo de resistencia al fluconazol.

Disaster mycology / Micología de desastres

Natural and human-made disasters have long played a role in shaping the environment and microbial communities, also affecting non-microbial life on Earth. Disaster microbiology is a new concept based on the notion that a disaster changes the environment causing adaptation or alteration of microbial populations-growth, death, transportation to a new area, development traits, or resistance-that can have downstream effects on the affected ecosystem. Such downstream effects include blooms of microbial populations and the ability to colonize a new niche or host, cause disease, or survive in former extreme conditions. Throughout history, fungal populations have been affected by disasters. There are prehistoric archeological records of fungal blooms after asteroid impacts and fungi implicated in the fall of the dinosaurs. In recent times, drought and dust storms have caused disturbance of soil fungi, and hurricanes have induced the growth of molds on wet surfaces, resulting in an increased incidence of fungal disease. Probably, the anticipated increase in extreme heat would force fungi adaptation to survive at high temperatures, like those in the human body, and thus be able to infect mammals. This may lead to a drastic rise of new fungal diseases in humans.

Los desastres naturales o los causados por el hombre impactan la formación de ecosistemas y comunidades microbianas, y también afectan las formas de vida no microbianas. Este concepto es conocido como "microbiología de desastres", una subespecialización de la microbiología, basada en los cambios ambientales generados por un desastre y las posibles adaptaciones o alteraciones de las poblaciones microbianas -crecimiento, muerte, trasporte a una nueva región, o adquisición de resistencia o de nuevas características- que influirán en el moldeamiento del ecosistema transformado. Algunos de los efectos de estas adaptaciones pueden ser: el surgimiento de poblaciones microbianas, la habilidad de colonizar nuevos nichos u huéspedes, la generación de nuevas enfermedades, o el crecimiento de microorganismos en condiciones que antes eran "extremas" para ellos. A lo largo de la historia, varias poblaciones de hongos han sido afectadas por desastres. Existen registros arqueológicos prehistóricos que evidencian la presencia y el crecimiento de hongos luego del impacto de asteroides, y otros de hongos relacionados con la extinción de los dinosaurios. Actualmente, las sequías y las tormentas de polvo causan perturbaciones en las comunidades de hongos del suelo, y los huracanes inducen el crecimiento de hongos filamentosos en superficies húmedas, lo que aumenta la cantidad de enfermedades por hongos. Además, con el aumento de las temperaturas extremas es posible que los hongos puedan adaptarse para sobrevivir a temperaturas más altas, equivalentes a las temperaturas corporales, y nuevas especies puedan infectar mamíferos. Esto puede llevar a un aumento drástico de las infecciones fúngicas en humanos.

Candida auris: a global pathogen that has taken root in Colombia / Candida auris: un agente patógeno global que se ha arraigado en Colombia

Candida auris has been recognized as an emerging multidrug-resistant pathogen with a significant public health burden, causing cases of invasive infection and colonization due to its persistence on inanimate surfaces, ability to colonize skin of some patients, and high transmissibility in healthcare settings. The first sporadic report of the isolation of this species from the ear canal of a patient in Asia was in 2009 and reports from other regions of the world soon followed. However, it was not until 2015 that global epidemiological alerts were communicated as a result of an increasing number of reports of invasive infections caused by C. auris in several countries. Colombia was soon added to this list in 2016 after an unusual increase in the number of C. haemulonii isolates was reported, later confirmed as C. auris. Since the issuing of a national alert by the Colombian National Institute of Health together with the Ministry of Health in 2016, the number of cases reported reached over 2,000 by 2022. Colombian isolates have not shown pan resistance to available antifungals, unlike C. auris strains reported in other regions of the world, which leaves patients in Colombia with therapeutic options for these infections. However, increasing fluconazole resistance is being observed. Whole-genome sequencing of Colombian C. auris isolates has enhanced molecular epidemiological data, grouping Colombian isolates in clade IV together with other South American isolates. Data from Colombia showed that public health authorities, scientific community, and the general public need to be aware of fungal diseases as they present an often-deadly threat to patients.

Candida auris ha sido reconocido como un agente patógeno multirresistente emergente con una carga significativa en la salud pública. Genera casos de infección invasiva y colonización debido a su persistencia en superficies inanimadas, su capacidad para colonizar fácilmente la piel de algunos pacientes y su alta transmisibilidad en el ambiente hospitalario. El primer reporte esporádico de esta especie fue en Asia en el 2009 cuando se realizó su aislamiento a partir del conducto auditivo de un paciente, y pronto le siguieron reportes en otras regiones del mundo. Sin embargo, no fue hasta 2015 que se conocieron las alertas epidemiológicas a nivel mundial debido a un aumento en el número de casos de infecciones causadas por C. auris en varios países. Colombia se sumó a la lista en 2016 luego de un aumento inusual en el número de aislamientos de C. haemulonii informados, que luego se confirmaron como C. auris. Desde que el Instituto Nacional de Salud junto con el Ministerio de Salud emitieron la Alerta Nacional en el 2016, el número de casos reportados superó los 2.000 en el 2022. Los aislamientos colombianos no han mostrado resistencia generalizada a los antifúngicos disponibles, contrario a lo reportado para cepas de C. auris en algunas regiones del mundo, por lo que los pacientes en Colombia aún cuentan con opciones terapéuticas para estas infecciones. No obstante, se ha observado un aumento en la resistencia al fluconazol. La secuenciación del genoma completo agrupó los aislamientos colombianos en el Ciado IV, junto con otros sudamericanos de C. auris, y aportó al conocimiento de los datos epidemiológicos moleculares de esta especie. Los datos de Colombia evidencian que las autoridades de salud pública, la comunidad científica y el público en general deben ser conscientes de las enfermedades fúngicas, ya que a menudo representan una amenaza mortal para los pacientes.

Actividad de fosfolipasas y proteasas en aislamientos de especies de Candida colonizadoras y causantes de vulvovaginitis en mujeres gestantes / Phospholipase and proteinase activities of isolatesof colonizing Candida spp. causing vulvovaginitis in pregnant women

Introducción. Las proteasas y las fosfolipasas son factores de virulencia de Candida spp. que cumplen un papel importante en la invasión de los tejidos. Entre los factores relacionados con el huésped, se encuentran algunos asociados con las características ambientales y otros con la colonización. Objetivo. Determinar la actividad de fosfolipasas y proteasas en aislamientos de especies colonizadoras y patógenas de Candida spp., aisladas de mujeres gestantes de Cartagena de Indias. Materiales y métodos. Se determinó la actividad de fosfolipasas y proteasas en 56 aislamientos mediante degradación del sustrato y cálculo del coeficiente de actividad enzimática. Se compararon las actividades de fosfolipasas y proteasas, entre los aislamientos colonizadores y los patógenos. Resultados. La actividad de la fosfolipasa fue "muy alta" (< 0,69) en 34 aislamientos e, igualmente, la de la proteasa en 14. No hubo diferencias significativas al comparar las actividades de las fosfolipasas y de las de las proteasas, entre los aislamientos colonizadores y los patógenos. Conclusiones. La actividad de las fosfolipasas predominó como factor de virulencia en los aislamientos estudiados. No obstante, no se encontró una diferencia significativa entre los grupos de aislamientos colonizadores y los patógenos, en cuanto a las actividades de fosfolipasas y proteasas.

Introduction. Proteases and phospholipases are virulence factors of Candida spp. that play an important role in tissue invasion. Among the factors related to the host some are associated with environmental characteristics and others with Candida colonization. Objectives. To determine phospholipase and protease activities in colonizing and pathogenic strains, isolated from pregnant women in Cartagena de Indias. Materials and methods. Phospholipase and protease activity was determined in 56 isolates, evaluating substrate degradation and calculating the enzyme activity coefficient. Phospholipase and protease activities were compared between colonizing and pathogenic strains. Results. "Very high" (<0.69) phospholipase and protease activity was found in 34 and 14 isolates, respectively. There was no significant difference when comparing phospholipase and protease activities between colonizing and pathogenic isolates. Conclusions. Phospholipase activity predominated as a virulence factor in the studied strains, but no significant difference was found between colonizing and pathogenic strains for phospholipase and protease activities.