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Importance: Multidrug resistance is a rising problem among non- Candida albicans species, such as Candida auris . This therapeutic problem has been very important during the COVID-19 pandemic. The World Health Organization has included C. auris in its global priority list of health-threatening fungi, to study this emerging multidrug-resistant species and to develop effective alternative therapies. In the present study, the synergistic effect of the combination of amphotericin B and echinocandins has been demonstrated against blood isolates of C. auris . Different susceptibility responses were also observed between aggregative and non-aggregative phenotypes. The antifungal activity of these drug combinations against C. auris was also demonstrated in the Caenorhabditis elegans host model of candidiasis, confirming the suitability and usefulness of this model in the search for solutions to antimicrobial resistance., Competing Interests: The authors declare no conflict of interest.

Candida auris is an emerging fungal pathogen responsible for hospital outbreaks of invasive candidiasis associated with high mortality. The treatment of these mycoses is a clinical challenge due to the high resistance levels of this species to current antifungal drugs, and alternative therapeutic strategies are needed. In this study, we evaluated the in vitro and in vivo activities of combinations of citral with anidulafungin, amphotericin B or fluconazole against 19 C. auris isolates. The antifungal effect of citral was in most cases similar to the effect of the antifungal drugs in monotherapy. The best combination results were obtained with anidulafungin, with synergistic and additive interactions against 7 and 11 of the 19 isolates, respectively. The combination of 0.06 μg/mL anidulafungin and 64 μg/mL citral showed the best results, with a survival rate of 63.2% in Caenorhabditis elegans infected with C. auris UPV 17-279. The combination of fluconazole with citral reduced the MIC of fluconazole from > 64 to 1-4 μg/mL against 12 isolates, and a combination of 2 μg/mL fluconazole and 64 μg/mL citral was also effective in reducing mortality in C. elegans . Amphotericin B combined with citral, although effective in vitro, did not improve the activity of each compound in vivo.

In vitro combination of echinocandins and isavuconazole against the emerging species Candida auris is mainly synergistic. However, this combination has not been evaluated in clinical settings. A pharmacokinetic/pharmacodynamic modeling and simulation approach based on in vitro data may be helpful to further study the therapeutic potential of these combinations. Therefore, the aims of this study were to characterize the time course of growth and killing of C. auris in response to the combination of the three approved echinocandins and isavuconazole using a semimechanistic model and to perform model-based simulations in order to predict the in vivo response to combination therapy. In vitro static time-kill curve data for isavuconazole and echinocandins combinations against six blood isolates of C. auris were best modeled considering the total killing of the fungal population as dependent on the additive effects of both drugs. Once assessed, the predictive performance of the model using simulations of different dosing and fungal susceptibility scenarios were conducted. Model-based simulations revealed that none of the combinations at standard or higher dosages would be effective against the studied isolates of C. auris and it was predicted that the combinations of isavuconazole with anidulafungin or caspofungin would be effective for minimum inhibitory concentrations up to 0.03 and 0.06 mg/L respectively, whereas the combination with micafungin would lead to treatment failure. The current approach highlights the importance of bridging the in vitro results to the clinic., (© 2023 The Authors. CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

The pathogenic yeast Pichia kudriavzevii, previously known as Candida krusei, is more distantly related to Candida albicans than clinically relevant CTG-clade Candida species. Its cell wall, a dynamic organelle that is the first point of interaction between pathogen and host, is relatively understudied, and its wall proteome remains unidentified to date. Here, we present an integrated study of the cell wall in P. kudriavzevii. Our comparative genomic studies and experimental data indicate that the general structure of the cell wall in P. kudriavzevii is similar to Saccharomyces cerevisiae and C. albicans and is comprised of β-1,3-glucan, β-1,6-glucan, chitin, and mannoproteins. However, some pronounced differences with C. albicans walls were observed, for instance, higher mannan and protein levels and altered protein mannosylation patterns. Further, despite absence of proteins with high sequence similarity to Candida adhesins, protein structure modeling identified eleven proteins related to flocculins/adhesins in S. cerevisiae or C. albicans. To obtain a proteomic comparison of biofilm and planktonic cells, P. kudriavzevii cells were grown to exponential phase and in static 24-h cultures. Interestingly, the 24-h static cultures of P. kudriavzevii yielded formation of floating biofilm (flor) rather than adherence to polystyrene at the bottom. The proteomic analysis of both conditions identified a total of 33 cell wall proteins. In line with a possible role in flor formation, increased abundance of flocculins, in particular Flo110, was observed in the floating biofilm compared to exponential cells. This study is the first to provide a detailed description of the cell wall in P. kudriavzevii including its cell wall proteome, and paves the way for further investigations on the importance of flor formation and flocculins in the pathogenesis of P. kudriavzevii., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Alvarado et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Candida albicans is an opportunistic pathogen that can thrive under adverse conditions including suboptimal pH, nutrient scarcity, and low levels of oxygen. Its pathogenicity is associated with the production of virulence factors such as extracellular hydrolytic enzymes and toxins. This study was aimed at determining the effect of external pH, substrate nature, and strain origin on protease, lipase, and hemolysin production. To achieve this objective, agar plate assays were performed at pH 5.0, 6.5, and 7.5 with substrates suitable for the detection of each family of enzymes. Moreover, the study was conducted with 20 clinical C. albicans isolates from blood, oral cavity, skin, urine, and vagina. The hydrolytic zones formed around the colonies were further measured to calculate the Ez (enzymatic zone) indexes. We found that detection of proteases in skim milk agar plates was possible for most isolates only at pH 5 (80%) and pH 6.5 (75%), whereas BSA plates could confer protease detection exclusively at pH 5 (80%). Similarly, the percentage of isolates possessing lipolytic activities was higher at pH 5 (90%) than at pH 6.5 (70%) and pH 7.5 (35%). In contrast, hemolytic activities were detected in all isolates at pH 6.5 and 7.5 but not at pH 5. Further analysis revealed that some differences in the detected activities could potentially be attributed to the anatomical origin of these isolates. Collectively, these findings suggest that the pH of the site of infection might be critical for mimicking the microenvironment employed to experimentally discover the key virulence factors., (© 2022 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

Mycoses are accountable for millions of infections yearly worldwide. Invasive candidiasis is the most usual, presenting a high morbidity and mortality. Candida albicans remains the prevalent etiologic agent, but the incidence of other species such as Candida parapsilosis , Candida glabrata and Candida auris keeps increasing. These pathogens frequently show a reduced susceptibility to commonly used antifungal drugs, including polyenes, triazoles and echinocandins, and the incidence of emerging multi-drug-resistant strains of these species continues to increase. Therefore, the need to search for new molecules that target these pathogenic species in a different manner is now more urgent than ever. Nature is an almost endless source of interesting new molecules that could meet this need. Among these molecules, antimicrobial peptides, present in different sources in nature, possess some advantages over conventional antifungal agents, even with their own drawbacks, and are considered as a promising pharmacological option against a wide range of microbial infections. In this review, we describe 20 antimicrobial peptides from different origins that possess an activity against Candida .

The study of the pharmacological properties of an antifungal agent integrates the drug pharmacokinetics, the fungal growth inhibition, the fungicidal effect and the postantifungal activity, laying the basis to guide optimal dosing regimen selection. The current manuscript reviews concepts regarding the postantifungal effect (PAFE) of the main classes of drugs used to treat Candida infections or candidiasis. The existence of PAFE and its magnitude are highly dependent on both the fungal species and the class of the antifungal agent. Therefore, the aim of this article was to compile the information described in the literature concerning the PAFE of polyenes, azoles and echinocandins against the Candida species of medical interest. In addition, the mechanisms involved in these phenomena, methods of study, and finally, the clinical applicability of these studies relating to the design of dosing regimens were reviewed and discussed. Additionally, different factors that could determine the variability in the PAFE were described. Most PAFE studies were conducted in vitro, and a scarcity of PAFE studies in animal models was observed. It can be stated that the echinocandins cause the most prolonged PAFE, followed by polyenes and azoles. In the case of the triazoles, it is worth noting the inconsistency found between in vitro and in vivo studies.

Background: Ibrexafungerp (SCY-078) is the newest oral and intravenous antifungal drug with broad activity, currently undergoing clinical trials for invasive candidiasis., Objective: The aim of this study was to assess the in vitro activity of ibrexafungerp and comparators against a collection of 434 European blood isolates of Candida ., Methods: Ibrexafungerp, caspofungin, fluconazole, and micafungin minimum inhibitory concentrations (MICs) were collected from 12 European laboratories for 434 blood isolates, including 163 Candida albicans , 108 Candida parapsilosis , 60 Candida glabrata , 40 Candida tropicalis , 29 Candida krusei , 20 Candida orthopsilosis , 6 Candida guilliermondii , 2 Candida famata , 2 Candida lusitaniae , and 1 isolate each of Candida bracarensis, Candida catenulata , Candida dubliniensis , and Candida kefyr . MICs were determined by the EUCAST broth microdilution method, and isolates were classified according to recommended clinical breakpoints and epidemiological cutoffs. Additionally, 22 Candida auris from different clinical specimens were evaluated., Results: Ibrexafungerp MICs ranged from 0.016 to ≥8 mg/L. The lowest ibrexafungerp MICs were observed for C. albicans (geometric MIC 0.062 mg/L, MIC range 0.016-0.5 mg/L) and the highest ibrexafungerp MICs were observed for C. tropicalis (geometric MIC 0.517 mg/L, MIC range 0.06-≥8 mg/L). Modal MICs/MIC 50 s (mg/L) against Candida spp. were 0.125/0.06 for C. albicans , 0.5/0.5 for C. parapsilosis , 0.25/0.25 for C. glabrata , 0.5/0.5 for C. tropicalis , 1/1 for C. krusei , 4/2 for C. orthopsilosis , and 0.5/0.5 for C. auris . Ibrexafungerp showed activity against fluconazole- and echinocandin-resistant isolates. If adopting wild-type upper limits, a non-wild-type phenotype for ibrexafungerp was only observed for 16/434 (3.7%) isolates: 11 (4.6%) C. parapsilosis , 4 (5%) C. glabrata , and 1 (2.5%) C. tropicalis ., Conclusion: Ibrexafungerp showed a potent in vitro activity against Candida ., Competing Interests: Outside the current study, we declare the following potential conflicts: GQ has received research grants from Astellas Pharma, Pfizer, Merck Sharp & Dohme, and SCYNEXIS. GQ has served on advisory/consultant boards for Merck, Sharp & Dohme, and SCYNEXIS, and he has received speaker honoraria from Abbvie, Astellas Pharma, Merck Sharp & Dohme, Pfizer, and SCYNEXIS. KB-E and DA are employed by SCYNEXIS. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Quindós, Miranda-Cadena, San-Millán, Borroto-Esoda, Cantón, Linares-Sicilia, Hamprecht, Montesinos, Tortorano, Prigitano, Vidal-García, Marcos-Arias, Guridi, Sanchez-Reus, Machuca-Bárcena, Rodríguez-Iglesias, Martín-Mazuelos, Castro-Méndez, López-Soria, Ruiz-Gaitán, Fernandez-Rivero, Lorenzo, Capilla, Rezusta, Pemán, Guarro, Pereira, Pais, Romeo, Ezpeleta, Jauregizar, Angulo and Eraso.)

Background: The ability of Candida to develop biofilms on inert surfaces or living tissues favors recalcitrant and chronic candidiasis associated, in many instances, with resistance to current antifungal therapy., Aim: The aim of this study was to evaluate the antifungal activity of citral, a phytocompound present in lemongrass essential oil, in monotherapy and combined with fluconazole against azole-resistant Candida planktonic cells and biofilms. The effect of citral combined with fluconazole was also analysed with regard to the expression of fluconazole resistance-associated genes in Candida albicans and the effectiveness of the combination therapy in a Caenorhabditis elegans model of candidiasis., Results: Citral reduced biofilm formation at initial stages and the metabolic activity of the mature biofilm. The combination of citral with fluconazole was synergistic, with a significant increase in the survival of C. elegans infected with Candida . RNA analysis revealed a reduction of the expression of the efflux pump encoded by MDR1 , leading to a greater effect of fluconazole., Conclusion: Citral in monotherapy and in combination with fluconazole could represent an interesting therapy to treat recalcitrant Candida infections associated to biofilms., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Candida auris is an emerging multidrug-resistant fungal pathogen responsible for nosocomial outbreaks of invasive candidiasis. Although several studies on the pathogenicity of this species have been reported, the knowledge on C. auris virulence is still limited. This study aims to analyze the pathogenicity of C. auris , using one aggregating isolate and eleven non-aggregating isolates from different clinical origins (blood, urine and oropharyngeal specimens) in two alternative host models of candidiasis: Caenorhabditis elegans and Galleria mellonella . Furthermore, possible associations between virulence, aggregation, biofilm-forming capacity, and clinical origin were assessed. The aggregating phenotype isolate was less virulent in both in vivo invertebrate infection models than non-aggregating isolates but showed higher capacity to form biofilms. Blood isolates were significantly more virulent than those isolated from urine and respiratory specimens in the G. mellonella model of candidiasis. We conclude that both models of candidiasis present pros and cons but prove useful to evaluate the virulence of C. auris in vivo . Both models also evidence the heterogeneity in virulence that this species can develop, which may be influenced by the aggregative phenotype and clinical origin.

Candida albicans is the major etiological agent of invasive candidiasis but the increasing prevalence of emerging species of Candida , such as Candida glabrata and phylogenetically closely related species, Candida nivariensis and Candida bracarensis , requires special attention. Differences in virulence among these species and their therapeutic responses using in vivo non-mammalian models are scarcely analysed. The aim of this study was analyse the survival of G. mellonella and host-pathogen interactions during infection by C. glabrata , C. nivariensis and C. bracarensis . Moreover, therapeutic responses to echinocandins were also assessed in the G. mellonella model of candidiasis. These three species produced lethal infection in G. mellonella ; C. glabrata was the most virulent species and C. bracarensis the less. Haemocytes of G. mellonella phagocytised C. bracarensis cells more effectively than those of the other two species. Treatment with caspofungin and micafungin was most effective to protect larvae during C. glabrata and C. nivariensis infections while anidulafungin was during C. bracarensis infection. The model of candidiasis in G. mellonella is simple and appropriate to assess the virulence and therapeutic response of these emerging Candida species. Moreover, it successfully allows for detecting differences in the immune system of the host depending on the virulence of pathogens.

Candida glabrata is among the most prevalent causes of candidiasis. Unlike Candida albicans , it is not capable of changing morphology between yeast and hyphal forms but instead has developed other virulence factors. An important feature is its unprecedented large repertoire of predicted cell wall adhesins, which are thought to enable adherence to a variety of surfaces under different conditions. Here, we analyzed the wall proteome of PEU1221, a high biofilm-forming clinical strain isolated from an infected central venous catheter, under biofilm-forming conditions. This isolate shows increased incorporation of putative adhesins, including eight proteins that were not detected in walls of reference strain ATCC 2001, and of which Epa22, Awp14, and Awp2e were identified for the first time. The proteomics data suggest that cluster III adhesin Awp14 is relatively abundant in PEU1221. Phenotypic studies with awp14Δ deletion mutants showed that Awp14 is not responsible for the high biofilm formation of PEU1221 onto polystyrene. However, awp14Δ mutant cells in PEU1221 background showed a slightly diminished binding to chitin and seemed to sediment slightly slower than the parental strain suggesting implication in fungal cell-cell interactions. By structural modeling, we further demonstrate similarity between the ligand-binding domains of cluster III adhesin Awp14 and those of cluster V and VI adhesins. In conclusion, our work confirms the increased incorporation of putative adhesins, such as Awp14, in high biofilm-forming isolates, and contributes to decipher the precise role of these proteins in the establishment of C. glabrata infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Fernández-Pereira, Alvarado, Gómez-Molero, Dekker, Blázquez-Muñoz, Eraso, Bader and de Groot.)

Oral candidiasis is frequently associated with Candida biofilms. Biofilms are microbial communities related to persistent, recalcitrant and difficult to-treat infections. Conventional treatments are not sufficient to overcome biofilm-associated candidiasis; thus, the search of new antifungal compounds is necessary. In the current study, we have evaluated the effect of three phytocompounds, carvacrol, cinnamaldehyde and thymol, against Candida planktonic and sessile cells. Reduction in biofilm biomass and metabolic activity was assessed during adhesion and mature biofilm phases. Candida albicans was the most biofilm-producing Candida species. All phytocompounds tested were fungicidal against Candida planktonic cells. Cinnamaldehyde was the most active in inhibiting biofilm adhesion, but carvacrol and thymol significantly reduced both mature biofilm biomass and metabolic activity. These results highlight the role of cinnamaldehyde, carvacrol and thymol as promising alternatives for the treatment of candidiasis due to their antibiofilm capacities, and stress the necessity to continue studies on their safety, toxicity and pharmacodynamics and pharmacokinetics., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The aims of this study were to characterize the antifungal activity of amphotericin B against Candida auris in a static in vitro system and to evaluate different dosing schedules and MIC scenarios by means of semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) modelling and simulation. A two-compartment model consisting of a drug-susceptible and a drug-resistant subpopulation successfully characterized the time-kill data and a modified E max sigmoidal model best described the effect of the drug. The model incorporated growth rate constants for both subpopulations, a death rate constant and a transfer constant between both compartments. Additionally, the model included a parameter to account for the delay in growth in the absence or presence of the drug. Amphotericin B displayed a concentration-dependent fungicidal activity. The developed PK/PD model was able to characterize properly the antifungal activity of amphotericin B against C. auris . Finally, simulation analysis revealed that none of the simulated standard dosing scenarios of 0.6, 1 and 1.5 mg/kg/day over a week treatment showed successful activity against C. auris infection. Simulations also pointed out that an MIC of 1 mg/L would be linked to treatment failure for C. auris invasive infections and therefore, the resistance rate to amphotericin B may be higher than previously reported.

Treatment of invasive infections caused by Candida auris is challenging due to the limited therapeutic options. The combination of antifungal drugs may be an interesting and feasible approach to be investigated. The aim of this study was to examine the in vitro activity of amphotericin B in combination with anidulafungin or caspofungin against C. auris . In vitro static time-kill curve experiments were conducted for 48 h with different combinations of amphotericin B with anidulafungin or caspofungin against six blood isolates of C. auris . The antifungal activity of 0.5 mg/L of amphotericin B was limited against the six isolates of C. auris . Similarly, echinocandins alone had a negligible effect, even at the highest tested concentrations. By contrast, 1 mg/L of amphotericin B showed fungistatic activity. Synergy was rapidly achieved (8 h) with 0.5 mg/L of amphotericin B plus 2 mg/L of anidulafungin or caspofungin. These combinations lead to a sustained fungistatic effect, and the fungicidal endpoint was reached against some C. auris isolates. Additionally, ≥0.5 mg/L of either of the two echinocandins with 1 mg/L of amphotericin B resulted in fungicidal effect against all C. auris isolates. In conclusion, combinations of amphotericin B with anidulafungin or caspofungin provided greater killing with a lower dose requirement for amphotericin B compared to monotherapy, with synergistic and/or fungicidal outcomes.

Candida parapsilosis is among the most frequent causes of candidiasis. Clinical isolates of this species show large variations in colony morphotype, ranging from round and smooth to a variety of non-smooth irregular colony shapes. A non-smooth appearance is related to increased formation of pseudohyphae, higher capacity to form biofilms on abiotic surfaces, and invading agar. Here, we present a comprehensive study of the cell wall proteome of C. parapsilosis reference strain CDC317 and seven clinical isolates under planktonic and sessile conditions. This analysis resulted in the identification of 40 wall proteins, most of them homologs of known Candida albicans cell wall proteins, such as Gas, Crh, Bgl2, Cht2, Ecm33, Sap, Sod, Plb, Pir, Pga30, Pga59, and adhesin family members. Comparative analysis of exponentially growing and stationary phase planktonic cultures of CDC317 at 30 °C and 37 °C revealed only minor variations. However, comparison of smooth isolates to non-smooth isolates with high biofilm formation capacity showed an increase in abundance and diversity of putative wall adhesins from Als, Iff/Hyr, and Hwp families in the latter. This difference depended more strongly on strain phenotype than on the growth conditions, as it was observed in planktonic as well as biofilm cells. Thus, in the set of isolates analyzed, the high biofilm formation capacity of non-smooth C. parapsilosis isolates with elongated cellular phenotypes correlates with the increased surface expression of putative wall adhesins in accordance with their proposed cellular function.

Candida auris is an emergent fungal pathogen that causes severe infectious outbreaks globally. The public health concern when dealing with this pathogen is mainly due to reduced susceptibility to current antifungal drugs. A valuable alternative to overcome this problem is to investigate the efficacy of combination therapy. The aim of this study was to determine the in vitro interactions of isavuconazole with echinocandins against C. auris . Interactions were determined using a checkerboard method, and absorbance data were analyzed with different approaches: the fractional inhibitory concentration index (FICI), Greco universal response surface approach, and Bliss interaction model. All models were in accordance and showed that combinations of isavuconazole with echinocandins resulted in an overall synergistic interaction. A wide range of concentrations within the therapeutic range were selected to perform time-kill curves. These confirmed that isavuconazole-echinocandin combinations were more effective than monotherapy regimens. Synergism and fungistatic activity were achieved with combinations that included isavuconazole in low concentrations (≥0.125 mg/L) and ≥1 mg/L of echinocandin. Time-kill curves revealed that once synergy was achieved, combinations of higher drug concentrations did not improve the antifungal activity. This work launches promising results regarding the combination of isavuconazole with echinocandins for the treatment of C. auris infections.

There is an increasing need for novel drugs and new strategies for the therapy of invasive candidiasis. This study aimed to develop and characterize liposome-based nanoparticles of carvacrol, cinnamaldehyde, citral, and thymol with anti- Candida activities. Dioctadecyldimethylammonium bromide- and monoolein-based liposomes in a 1:2 molar ratio were prepared using a lipid-film hydration method. Liposomes were assembled with equal volumes of liposomal stock dispersion and stock solutions of carvacrol, cinnamaldehyde, citral, or thymol in dimethyl sulfoxide. Cytotoxicity was tested on RAW 264.7 macrophages. In vitro antifungal activity of liposomes with phytocompounds was evaluated according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodology using clinical isolates of Candida albicans , Candida auris , Candida dubliniensis , and Candida tropicalis Finally, the ability of macrophage cells to kill Candida isolates after addition of phytocompounds and their nanoparticles was determined. Nanoparticles with 64 μg/ml of cinnamaldehyde, 256 μg/ml of citral, and 128 μg/ml of thymol had the best characteristics among the formulations tested. The highest encapsulation efficiencies were achieved with citral (78% to 83%) and carvacrol (66% to 71%) liposomes. Carvacrol and thymol in liposome-based nanoparticles were nontoxic regardless of the concentration. Moreover, carvacrol and thymol maintained their antifungal activity after encapsulation, and there was a significant reduction (∼41%) of yeast survival when macrophages were incubated with carvacrol or thymol liposomes. In conclusion, carvacrol and thymol liposomes possess high stability, low cytotoxicity, and antifungal activity that act synergistically with macrophages., (Copyright © 2021 American Society for Microbiology.)

Background: The pathogen Candida auris is rapidly gaining clinical importance because of its resistance to antifungal treatments and its persistence in hospital environments. Early and accurate diagnosis of C. auris infections is crucial, and however, the fungus has often been misidentified by commercial systems., Objectives: To develop conventional and real-time PCR methods for accurate and rapid identification of C. auris and its discrimination from closely related species by exploiting the uniqueness of certain glycosylphosphatidylinositol (GPI)-modified protein-encoding genes., Methods: Species-specific primers for two unique putative GPI protein-encoding genes per species were designed for C. auris, C. haemulonii, C. pseudohaemulonii, C. duobushaemulonii, C. lusitaniae and C. albicans. Primers were blind tested for their specificity and efficiency in conventional and real-time multiplex PCR set-up., Results: All primers combinations showed excellent species specificity. In multiplex mode, correct identification was aided by different-sized amplicons for each species. Efficiency of the C. auris primers was validated using a panel of 155 C. auris isolates, including all known genetically diverse clades. In real-time multiplex PCR, different melting points of the amplicons allowed the distinction of C. auris from four related species. C. auris limit of detection was 5 CFU/reaction with a threshold value of 32. The method was also able to detect C. auris in spiked blood and serum., Conclusions: PCR identification based on unique GPI protein-encoding genes allows for accurate and rapid species identification of C. auris and related species without need for expensive equipment when applied in conventional PCR set-up., (© 2020 Wiley-VCH GmbH.)

Candidiasis caused by species of the Candida haemulonii complex ( Candida haemulonii and Candida duobushaemulonii ) and closely related species, Candida auris and Candida pseudohaemulonii are increasing. These species often show reduced susceptibility to antifungal drugs, such as azoles and amphotericin B or, less frequently, echinocandins. However, conventional phenotypic identification methods are unable to accurately differentiate these species and, therefore, their prevalence may have been underestimated. In this study, 150 isolates that were probably misidentified were reanalyzed using two novel PCR approaches. We found that one isolate previously identified in 1996 as Candida intermedia was C. duobushaemulonii , being one of the oldest isolates of this species described to date. We also found that this isolate had reduced susceptibility to fluconazole, itraconazole, and amphotericin B.

Although Candida albicans remains the major etiological agent of invasive candidiasis, Candida glabrata and other emerging species of Candida are increasingly isolated. This species is the second most prevalent cause of candidiasis in many regions of the world. However, clinical isolates of Candida nivariensis and Candida bracarensis can be misidentified and are underdiagnosed due to phenotypic traits shared with C. glabrata Little is known about the two cryptic species. Therefore, pathogenesis studies are needed to understand their virulence traits and their susceptibility to antifungal drugs. The susceptibility of Caenorhabditis elegans to different Candida species makes this nematode an excellent model for assessing host-fungus interactions. We evaluated the usefulness of C. elegans as a nonconventional host model to analyze the virulence of C. glabrata , C. nivariensis , and C. bracarensis The three species caused candidiasis, and the highest virulence of C. glabrata was confirmed. Furthermore, we determined the efficacy of current antifungal drugs against the infection caused by these species in the C. elegans model. Amphotericin B and azoles showed the highest activity against C. glabrata and C. bracarensis infections, while echinocandins were more active for treating those caused by C. nivariensis C. elegans proved to be a useful model system for assessing the pathogenicity of these closely related species., (Copyright © 2020 American Society for Microbiology.)

Background: Candida parapsilosis is the second or third most frequently isolated Candida species related to nosocomial infections, even overtaking Candida albicans in some hospitals. C. parapsilosis constitutes a complex of closely related species: Candida parapsilosis sensu stricto, Candida orthopsilosis and Candida metapsilosis. Accurate detection of these species is of importance, as the incidence of C. orthopsilosis has been reported to surpass that of Candida krusei., Objective: To evaluate the diagnostic utility of two PCR-RFLP methods targeting the SADH and FKS1 genes and to determine the prevalence of cryptic species in 96 bloodstream isolates of C. parapsilosis from 93 patients., Methods: Restriction patterns of the SADH and FKS1 genes were analysed, and sequencing of the D1/D2 regions of the ribosomal RNA was used to evaluate the reliability of both PCR-RFLP methods., Results: In our study, 77 C. parapsilosis sensu stricto, 13 C. orthopsilosis and five C. metapsilosis were identified by sequencing. Both PCR-RFLP methods demonstrated strong agreement with D1/D2 sequencing in the identification of C. parapsilosis and C. orthopsilosis, while both methods were unable to identify the C. metapsilosis isolates. Moreover, unexpected restriction patterns were observed for two isolates on SADH PCR-RFLP and for four isolates on FKS1 PCR-RFLP. Mixed bloodstream infections of C. parapsilosis sensu stricto and C. orthopsilosis were detected for three patients, for which differential growth characteristics were observed., Conclusion: The molecular method chosen for identification could have an impact on determination of the real prevalence of C. metapsilosis in candidaemia, and mixed fungaemias can remain undetected., (© 2020 Blackwell Verlag GmbH.)

Background: Morphological, physical and chemical properties of both implants and prostheses can determine the biofilm formation on their surface and increase the risk of biological complications. The aim of this study was to evaluate the capacity of biofilm formation of Candida albicans on different materials used to manufacture abutments and prostheses., Material and Methods: Biofilm formation was analyzed on cp grade II titanium, cobalt-chromium alloy and zirconia, silicone, acrylic resin (polymethylmethacrylate) and nano-hybrid composite. Some samples were partially covered with lithium disilicate glass ceramic to study specifically the junction areas.C. albicans was incubated in a biofilm reactor at 37 °C with agitation. The biofilm formation was evaluated at 24 and 48 hours. In addition, the morphology of the biofilm was evaluated by scanning electron microscopy., Results: C. albicans developed biofilms on the surface of all materials tested. Cobalt-chromium alloy showed the lowest density of adhered biofilm, followed by zirconia and titanium. Silicone and resin showed up to 20 times higher density of biofilm. A higher biofilm formation was observed when junctions of materials presented micropores or imperfections., Conclusions: The biofilm formed in the three materials used in the manufacture of abutments and prostheses showed no major differences, being far less dense than in the resins. Two clinical recommendations can be made: to avoid the presence of resins in the subgingival area of implant prostheses and to design prostheses placing cobalt-chromium alloy/ceramic or titanium/ceramic junctions as far as possible from implants.

Healthcare-associated infections (HAIs) can be caused by microorganisms present in common practice instruments generating major health problems in the hospital environment. The aim of this work was to evaluate the disinfection capacity of a portable ultraviolet C equipment (UV Sanitizer Corvent ® -UVSC-) developed to disinfect different objects. For this purpose, six pathogens causing HAIs: Acinetobacter baumannii , Bacillus subtilis , Escherichia coli , Pseudomonas aeruginosa , Staphylococcus aureus and Candida albicans , were inoculated on slides and discs of different biomaterials (borosilicate, polycarbonate, polyurethane, silicone, Teflon and titanium) and exposed to ultraviolet C radiation. UVSC disinfection was compared with ethanol and chlorhexidine antimicrobial activities following the standards EN14561 and EN14562. Disinfection, established as a reduction of five logarithms from the initial inoculum, was achieved with the UVSC at 120 s of exposure time, with and without the presence of organic matter. The disinfectant effect was observed against S. aureus , P. aeruginosa , E. coli , B. subtilis and C. albicans (reduction >99.999%). Disinfection was also achieved with 70% ethanol and 2% chlorhexidine. As conclusion, UVSC was effective disinfecting the most contaminated surfaces assayed, being a promising alternative for disinfecting hospital materials and inanimate objects that cannot be immersed in liquid biocides, reducing the risk of pathogen transmission.

Most hospitalized patients are carriers of biomedical devices. Infections associated with these devices cause great morbidity and mortality, especially in patients in intensive care units. Numerous strategies have been designed to prevent biofilm development on biodevices. However, biofilm formation is a complex process not fully clarified. In the current study, roughness and hydrophobicity of different biomaterials was analyzed to assess their influences on the biofilm formation of four leading etiological causes of healthcare-associated infections, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis and Candida albicans, using a CDC biofilm reactor. Hydrophobic materials allowed the formation of more abundant and profuse biofilms. Roughness had effect on biofilm formation, but its influence was not significant when material hydrophobicity was considered.

Objective: Candida albicans remains the most common aetiology of invasive candidiasis, leading to high morbidity and mortality. Nevertheless, the incidence of candidiasis due to non-C. albicans species, such as Candida parapsilosis, is increasing. Postantifungal effect (PAFE) is relevant for establishing dosage schedules in antifungal therapy, as the frequency of antifungal administration could change depending on PAFE. The aim of this study was to evaluate the PAFE of anidulafungin against C. albicans, Candida dubliniensis, Candida africana, C. parapsilosis, Candida metapsilosis and Candida orthopsilosis., Methods: Twenty-one Candida strains were evaluated. Cells were exposed to anidulafungin for 1 h at concentrations ranging from 0.12 to 8 mg/L for PAFE studies. Time-kill experiments (TK) were conducted at the same concentrations. The experiments were performed using an inoculum of 1-5 x 105 cells/mL and 48 h incubation. Readings of PAFE and TK were done at 0, 2, 4, 6, 24 and 48 h., Results: Anidulafungin was fungicidal against 2 out of 14 (14%) strains of C. albicans related species in PAFE experiments. Moreover, 2 mg/L of anidulafungin exerted a prolonged PAFE (≥ 33.6 h) against 13 out of 14 (93%) strains. Similarly, fungicidal endpoint was achieved against 1 out of 7 (14%) strains of C. parapsilosis complex, being PAFE prolonged (≥ 42 h) against 6 out of 7 (86%) strains., Conclusions: Anidulafungin induced a significant and prolonged PAFE against C. albicans and C. parapsilosis and their related species., (©The Author 2019. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)

Background: Candidiasis is one of the most common opportunistic oral infections that presents different acute and chronic clinical presentations with diverse diagnostic and therapeutic approaches. The present study carries out a bibliographic review on the therapeutic tools available against oral candidiasis and their usefulness in each clinical situation., Material and Methods: Recent studies on treatment of oral candidiasis were retrieved from PubMed and Cochrane Library., Results: Nystatin and miconazole are the most commonly used topical antifungal drugs. Both antifungal drugs are very effective but need a long time of use to eradicate the infection. The pharmacological presentations of miconazole are more comfortable for patients but this drug may interact with other drugs and this fact should be assessed before use. Other topical alternatives for oral candidiasis, such as amphotericin B or clotrimazole, are not available in many countries. Oral fluconazole is effective in treating oral candidiasis that does not respond to topical treatment. Other systemic treatment alternatives, oral or intravenous, less used are itraconazole, voriconazole or posaconazole. Available novelties include echinocandins (anidulafungin, caspofungin) and isavuconazole. Echinocandins can only be used intravenously. Isavuconazole is available for oral and intravenous use. Other hopeful alternatives are new drugs, such as ibrexafungerp, or the use of antibodies, cytokines and antimicrobial peptides., Conclusions: Nystatin, miconazole, and fluconazole are very effective for treating oral candidiasis. There are systemic alternatives for treating recalcitrant infections, such as the new triazoles, echinocandins, or lipidic presentations of amphotericin B.

Background: Candida parapsilosis, Candida metapsilosis and Candida orthopsilosis are emerging as relevant causes of candidemia. Moreover, they show differences in their antifungal susceptibility and virulence. The echinocandins are different in terms of in vitro antifungal activity against Candida. Time-kill (TK) curves represent an excellent approach to evaluate the fungicidal activity of antifungal drugs., Aims: To compare the fungicidal activities of anidulafungin, caspofungin and micafungin against C. parapsilosis species complex by TK curves., Methods: Antifungal activities of three echinocandins against C. parapsilosis, C. metapsilosis and C. orthopsilosis were studied by TK curves. Drug concentrations assayed were 0.25, 2 and 8μg/ml. CFU/ml were determined at 0, 2, 4, 6, 24 and 48h., Results: Killing activities of echinocandins were species-, isolates- and concentration-dependent. Anidulafungin reached the fungicidad endpoint for 6 out of 7 isolates (86%); it required between 13.34 and 29.67h to reach this endpoint for the three species studied, but more than 48h were needed against one isolate of C. orthopsilosis (8μg/ml). Caspofungin fungicidal endpoint was only achieved with 8μg/ml against one isolate of C. metapsilosis after 30.12h (1 out of 7 isolates; 14%). Micafungin fungicidal endpoint was reached in 12.74-28.38h (8μg/ml) against one isolate each of C. parapsilosis and C. orthopsilosis, and against both C. metapsilosis isolates (4 out of 7 isolates; 57%)., Conclusions: C. metapsilosis was the most susceptible species to echinocandins, followed by C. orthopsilosis and C. parapsilosis. Anidulafungin was the most active echinocandin against C. parapsilosis complex., (Copyright © 2019 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background: Candidiasis is a major cause of human morbidity and mortality. Human uterine cervical stem cells conditioned medium (hUCESC-CM) is obtained from stromal stem cells of the cervical transformation zone, which are in permanent contact with a wide array of potential vaginal pathogens. In previous reports we have found that hUCESC-CM has antitumor and antibacterial potential. Since Candida is the most prevalent yeast in the human vagina, it seems plausible that hUCESC-CM might also show activity against it. Methods: In a preliminary step, to evaluate if hUCESC-CM showed any activity at all on Candida growth, in vitro activities of hUCESC-CM against fluconazole-susceptible reference strains of Candida albicans, Candida glabrata, Candida krusei , and Candida parapsilosis were studied with a microdilution method on RPMI 1640, using the BioScreen C microbiological incubator. Each measurement was repeated five times. The same methodology was used subsequently on fluconazole-susceptible and fluconazole-resistant Candida isolates from blood and vagina of those species corresponding to the reference strains of Candida against which activity had been detected in the previous study. Moreover, two fluconazole-resistant clinical isolates of Candida auris from blood and urine were also included. Findings: In vitro inhibitory activity of hUCESC-CM ranged from 57.5 to 96.6% growth-reduction against fluconazole-susceptible reference strains of Candida albicans, Candida glabrata , and Candida parapsilosis . hUCESC-CM also reduced the growth of all fluconazole-susceptible tested vaginal isolates by more than 50%. For fluconazole-resistant isolates, growth-reduction was higher than 67% for Candida albicans , regardless of its origin (vagina or blood). The isolate of Candida auris from urine with a MIC > 128 μ/ml for fluconazole was also significantly inhibited. However, hUCESC-CM was almost inactive against any of the fluconazole-resistant blood isolates of Candida glabrata, Candida parapsilosis , and Candida auris tested. Interpretation: This is the first report about the growth-inhibiting properties of conditioned medium from human stromal stem cells against different species of Candida . Antifungal activity of stromal stem cells depends on their site of origin, being most effective against Candida species most prevalent at that particular location. If confirmed in further studies, these findings might result in a completely new therapeutic approach against superficial and invasive candidiasis.

Objective: To evaluate the importance of Candida glabrata, Candida parapsilosis and their close-related species, Candida bracarensis, Candida nivariensis, Candida metapsilosis and Candida orthopsilosis in patients with oral candidiasis and, to determine the in vitro activities of antifungal drugs currently used for the treatment., Methods: One hundred fourteen isolates of C. glabrata and 97 of C. parapsilosis, previously identified by conventional mycological methods, were analysed by molecular techniques. In vitro antifungal susceptibility to fluconazole, itraconazole, miconazole, and nystatin was evaluated by CLSI M44-A2 disk diffusion test, and by CLSI M27-A3 microdilution for fluconazole., Results: All C. glabrata isolates were identified as C. glabrata sensu stricto, 93 out of 97 C. parapsilosis isolates as C. parapsilosis sensu stricto, three as C. orthopsilosis and one as C. metapsilosis. Candida glabrata was mainly isolated in mixed cultures but C. parapsilosis complex was more frequent in pure culture. Candida metapsilosis and C. orthopsilosis were isolated as pure culture and both species were susceptible to all antifungal agents tested. Most C. glabrata isolates were susceptible to miconazole and nystatin, but resistant to fluconazole and itraconazole. Azole cross resistance was also observed. Candida parapsilosis isolates were susceptible to fluconazole although azole cross resistance to miconazole and itraconazole was observed., Conclusion: This study highlights the importance of accurate identification and antifungal susceptibility testing of oral Candida isolates in order to have an in-depth understanding of the role of C. glabrata and C. parapsilosis in oral candidiasis., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The emerging multidrug-resistant pathogenic yeast Candida auris causes life-threatening invasive infections and shows a capacity for hospital transmission that is uncommon in other Candida species. Rapid and accurate diagnosis of C. auris infections is crucial; however, the fungus is frequently misidentified. Here, we present a rapid and easily applicable PCR assay for reliable identification of C. auris by designing primers from unique GPI protein-encoding genes. Specificity of the used primers for C. auris was verified with a panel of 19 different Candida species including the clinically most relevant and phylogenetically closely related species. Efficacy of the PCR approach was validated by correctly identifying 112 C. auris isolates from an outbreak in a Spanish hospital, 20% of which were not reliably identified by MALDI-TOF MS, and 27 genotypically diverse C. auris isolates originating from hospitals in various countries, in a test that included (blind) negative controls. By employing two GPI protein primer pairs in a single PCR, a double screening can be performed, which enhances the robustness of the PCR assay and avoids potential false negatives due to recent evolutionary events, as was observed for two isolates. Our PCR method, which is based on the uniqueness of selected GPI protein-encoding genes, is useful for easy, low-cost, and accurate identification of C. auris infections in a clinical setting., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Background: Analysis of polymorphic microsatellite markers (STR) is a helpful genotyping technique to differentiate Candida parapsilosis sensu stricto isolates. The aim of this study is to develop and perform an initial validation of an alternative protocol for the reliable and accurate microsatellite genotyping of C. parapsilosis sensu stricto isolates using high-throughput multiplex PCR. To achieve this, the results obtained using the new protocol were compared to the ones obtained using a previously described reference method. To that end, diagnostic accuracy, informativeness and discrimination parameters were estimated., Results: Our results showed good concordance between both methods (Kappa index: 0.920), leading to a high sensitivity (1; CI(95%) (0.991-1)) and specificity (1; CI(95%) (0.772-1)) after the validation of the new protocol. Moreover, the electropherograms profiles obtained with the new PCR scheme showed a high signal to noise ratio (SNR)., Conclusions: The new multiplex protocol is valuable for the differentiation of C. parapsilosis sensu stricto, with direct clinical applications. Besides, the new protocol represents a shortening the hands-on time, reducing the sample manipulation (dismissing the possibility of cross-contamination), maintaining the quality of the results (when compared to the ones obtained with the reference method), and helping to the standardization and simplification of the genotyping scheme.

Recent changes in the aetiology and epidemiology of invasive candidiasis have serious implications for current and future diagnosis, treatment and prognosis. The aim of the current review was to discuss the epidemiology of invasive candidiasis, the distribution of Candida species in different regions of the world, the medical concerns of the changing aetiology and the emergence of antifungal resistance. Overall burden of invasive candidiasis remains high, especially in vulnerable persons, such as the elderly, immunosuppressed or debilitated patients. Moreover, there is a progressive shift in the aetiology of invasive candidiasis from Candida albicans to other species of Candida, probably related to the increased use of azole drugs with a clear trend towards increased antifungal resistance. Finally, the emergence and rise of multiresistant species, such as Candida auris or Candida glabrata, is a major threat making necessary invasive candidiasis worldwide surveillances. These changes have serious implications for the diagnosis, treatment and prognosis of invasive candidiasis. Updated knowledge of the current local epidemiology of invasive candidiasis is critical for the clinical management.

Background: Candida can be implicated in the pathology of chronic periodontitis., Aims: To analyze the oral Candida carriage in patients suffering from chronic periodontitis (CP) and its correlation with the severity of this condition., Methods: Microbiological samples were taken from 155 patients using the oral rinse (OR) technique and by using paper points in the periodontal pockets (GPP). These patients were divided into 3 groups: 89 patients without CP (control), 47 with moderate CP, and 19 with severe CP. Samples were cultured in a Candida chromogenic agar for Candida. Species were identified by microbiological and molecular methods., Results: Candida was isolated in the OR of 45 (50.6%), 21 (44.7%), and 11 (57.9%) patients, respectively, and in the GPP of 32 (36%), 14 (29.2%), and 10 (42.6%) patients from the control, moderate CP and severe CP groups, respectively. Candida was isolated more frequently and in a greater burden in OR than in GPP (p<0.01). Candida albicans was the most prevalent species. GPP of patients with CP had poor fungal biodiversity (p<0.01)., Conclusions: Colonization by Candida was present in the samples of patients without CP, and with both moderate and severe CP. Nonetheless, patients with severe CP had a higher rate of Candida colonization, especially by C. albicans., (Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Invasive candidiasis is caused mainly by Candida albicans, but other Candida species have increasing etiologies. These species show different virulence and susceptibility levels to antifungal drugs. The aims of this study were to evaluate the usefulness of the non-conventional model Caenorhabditis elegans to assess the in vivo virulence of seven different Candida species and to compare the virulence in vivo with the in vitro production of proteinases and phospholipases, hemolytic activity and biofilm development capacity. One culture collection strain of each of seven Candida species (C. albicans, Candida dubliniensis, Candida glabrata, Candida krusei, Candida metapsilosis, Candida orthopsilosis and Candida parapsilosis) was studied. A double mutant C. elegans AU37 strain (glp-4;sek-1) was infected with Candida by ingestion, and the analysis of nematode survival was performed in liquid medium every 24 h until 120 h. Candida establishes a persistent lethal infection in the C. elegans intestinal tract. C. albicans and C. krusei were the most pathogenic species, whereas C. dubliniensis infection showed the lowest mortality. C. albicans was the only species with phospholipase activity, was the greatest producer of aspartyl proteinase and had a higher hemolytic activity. C. albicans and C. krusei caused higher mortality than the rest of the Candida species studied in the C. elegans model of candidiasis.

Caries and chronic periodontitis are common oral diseases where a higher Candida colonization is reported. Antifungal agents could be adjuvant drugs for the therapy of both clinical conditions. The aim of the current study has been to evaluate the in vitro activities of conventional and new antifungal drugs against oral Candida isolates from patients suffering from caries and/or chronic periodontitis. In vitro activities of amphotericin B, fluconazole, itraconazole, miconazole, nystatin, posaconazole and voriconazole against 126 oral Candida isolates (75 Candida albicans, 18 Candida parapsilosis, 11 Candida dubliniensis, six Candida guilliermondii, five Candida lipolytica, five Candida glabrata, four Candida tropicalis and two Candida krusei) from 61 patients were tested by the CLSI M27-A3 method. Most antifungal drugs were highly active, and resistance was observed in less than 5% of tested isolates. Miconazole was the most active antifungal drug, being more than 98% of isolates susceptible. Fluconazole, itraconazole, and the new triazoles, posaconazole and voriconazole, were also very active. Miconazole, fluconazole and voriconazole have excellent in vitro activities against all Candida isolates and could represent suitable treatment for a hypothetically adjunctive therapy of caries and chronic periodontitis.

Background and Objectives: During a community methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization study, an MRSA strain with vancomycin hetero-resistance (h-VISA) was isolated from a five year-old girl with tetralogy of Fallot without previous exposure to vancomycin. An extended nasal colonization study was performed on all her close relatives., Results: Only the patient and her sister were colonized by an h-VISA MRSA strain (clone USA 700, ST72, t148, agr 1 and SCCmec IVa). Mupirocin decolonisation was effective in the elder sister. A new nasal decolonisation in the younger girl using fusidic acid was also successful. However, after decolonisation both sisters were colonized by a methicillin-susceptible S. aureus (ST30, t012 and agr 3) previously isolated from their mother's nostrils., Conclusion: As S. aureus have a great capacity to spread among people in close contact, knowledge of a patients' colonization status, tracing contacts, and a correct management are critical issues for the successful containment of multiresistant staphylococci., (Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

A cross-sectional study was performed in 10 emergency basic life support ambulances operating in Bilbao, Spain, to assess surface bacterial contamination. Presence of clinically relevant bacterial contamination suggests that disinfection of the studied basic life support ambulances was not optimal and represents a potential risk of infection for the patients transferred in them. It is critical to implement existing infection control and prevention protocols to resolve this issue., (Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Killing and postantifungal effects could be relevant for the selection of optimal dosing schedules. This study aims to compare time-kill and postantifungal effects with caspofungin on Candida albicans (C. albicans, Candida dubliniensis, Candida africana) and Candida parapsilosis (C. parapsilosis, Candida metapsilosis, Candida orthopsilosis) clades. In the postantifungal effect experiments, strains were exposed to caspofungin for 1 h at concentrations 0.12-8 μg/mL. Time-kill experiments were conducted at the same concentrations. Caspofungin exhibited a significant and prolonged postantifungal effect (>37 h) with 2 μg/mL against the most strains of C. albicans clade. Against the C. parapsilosis clade, the postantifungal effect was <12 h at 8 μg/mL, except for two strains. Caspofungin was fungicidal against C. albicans, C. dubliniensis and C. metapsilosis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Candida albicans is one of the most frequent pathogens of the oral cavity, as a major cause of opportunistic disease. Moreover, Candida could be a cofactor of common oral diseases, such as dental caries. The aim of this study was to analyse the oral yeast colonisation in adults with dental caries and to evaluate its relationship with this clinical entity. We studied 190 patients distributed into controls (58 patients) and patients with caries (132 patients). Oral samples were collected by oral rinse and cultured in a chromogenic agar. C. albicans was the most prevalent species isolated from oral specimens in both groups. Patients with caries had a greater Candida colonisation (74 patients, 56.1%), than persons without caries (18 patients, 31%, P < 0.01). Patients with caries were significantly more colonised by non-C. albicans species than individuals without caries (P = 0.006). Moreover, the diversity of Candida species was richer in patients suffering from caries. The odds ratio of the colonisation of patients with caries was 3.144 (95% CI 1.525-5.478). There is a significant clinical correlation between dental caries and oral Candida colonisation in adults., (© 2016 Blackwell Verlag GmbH.)

The aim of this study was to fit anidulafungin in vitro static time-kill data from nine strains of Candida with a pharmacodynamic (PD) model in order to describe the antifungal activity of this drug against Candida spp. Time-kill data from strains of Candida albicans, Candida glabrata and Candida parapsilosis clades were best fit using an adapted sigmoidal Emax model and resulted in a set of PD parameters (Emax, EC50 and Hill factor) for each fungal strain. The data were analysed with NONMEM 7. Anidulafungin was effective in a species- and concentration-dependent manner against the strains of C. glabrata and C. parapsilosis clades as observed with the EC50 estimates. Maximum killing rate constant (Emax) values were higher against C. glabrata and C. parapsilosis complex strains. In conclusion, we demonstrated that the activity of anidulafungin against Candida can be accurately described using an adapted sigmoidal Emax model., (Copyright © 2016 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)

Current therapy for mycoses is limited to the use of a relative reduced number of antifungal drugs. Although amphotericin B still remains considered as the "gold standard" for treatment, acute and chronic toxicity, such as impairment of renal function, limits its use and enhances the investigation and clinical use other chemical families of antifungal drugs. One of these chemical class of active drugs are azole derivatives, discovered in 70s and introduced in clinical practice in 80s. Being the most prolific antifungal class, investigation about more molecules, with a safer and better pharmacological profile, active against a wide spectrum of fungi, with a wide range of administration routes gives us some azole representatives.

Micafungin is an effective antifungal agent useful for the therapy of invasive candidiasis. Candida albicans is the most common cause of invasive candidiasis; however, infections due to non-C. albicans species, such as Candida parapsilosis, are rising. Killing and postantifungal effects (PAFE) are important factors in both dose interval choice and infection outcome. The aim of this study was to determinate the micafungin PAFE against 7 C. albicans strains, 5 Candida dubliniensis, 2 Candida Africana, 3 C. parapsilosis, 2 Candida metapsilosis and 2 Candida orthopsilosis. For PAFE studies, cells were exposed to micafungin for 1 h at concentrations ranging from 0.12 to 8 μg/ml. Time-kill experiments (TK) were conducted at the same concentrations. Samples were removed at each time point (0-48 h) and viable counts determined. Micafungin (2 μg/ml) was fungicidal (≥ 3 log10 reduction) in TK against 5 out of 14 (36%) strains of C. albicans complex. In PAFE experiments, fungicidal endpoint was achieved against 2 out of 14 strains (14%). In TK against C. parapsilosis, 8 μg/ml of micafungin turned out to be fungicidal against 4 out 7 (57%) strains. Conversely, fungicidal endpoint was not achieved in PAFE studies. PAFE results for C. albicans complex (41.83 ± 2.18 h) differed from C. parapsilosis complex (8.07 ± 4.2 h) at the highest tested concentration of micafungin. In conclusion, micafungin showed significant differences in PAFE against C. albicans and C. parapsilosis complexes, being PAFE for the C. albicans complex longer than for the C. parapsilosis complex.

Candida albicans remains the most common fungal pathogen. This species is closely related to 2 phenotypically similar cryptic species, Candida dubliniensis and Candida africana. This study aims to compare the antifungal activities of echinocandins against 7 C. albicans, 5 C. dubliniensis, and 2 C. africana strains by time-kill methodology. MIC values were similar for the 3 species; however, differences in killing activity were observed among species, isolates, and echinocandins. Echinocandins produced weak killing activity against the 3 species. In all drugs, the fungicidal endpoint (99.9% mortality) was reached at ≤31 h with ≥0.5 μg/mL for anidulafungin in 4 C. albicans and 1 C. dubliniensis, for caspofungin in 1 C. albicans and 2 C. dubliniensis, and for micafungin in 4 C. albicans and 1 C. dubliniensis. None of echinocandins showed lethality against C. africana. Identification of these new cryptic species and time-kill studies would be recommendable when echinocandin treatment fails., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Anidulafungin, caspofungin, and micafungin killing activities against Candida glabrata, Candida bracarensis, and Candida nivariensis were evaluated by the time-kill methodology. The concentrations assayed were 0.06, 0.125, and 0.5 μg/ml, which are achieved in serum. Anidulafungin and micafungin required between 13 and 26 h to reach the fungicidal endpoint (99.9% killing) against C. glabrata and C. bracarensis. All echinocandins were less active against C. nivariensis., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Superficial candidiasis of the oral cavity, vagina and the skin are common mild infections though they may be recalcitrant, as in the case of recurrent vaginitis or denture stomatitis. However, in debilitated people with immune deficiencies, Candida can cause serious invasive infections with high mortality. Both types of patients could benefit from the development of vaccines and monoclonal or polyclonal antibodies of utility for a passive immunization, according to their immune status. Several antigens as mannans, β-glucans, various adhesins, heat shock protein 90 and acid secreted proteinases can be very useful for the vaccines development. There is a broad and sound experience with many of these antigens in animal models, mainly in rabbits and mice. However, only two vaccines, based on recombinant antigens (rAls3p-N and rSap2t) are currently being tested in clinical trials.