Human Papilloma Virus DNA Detection in Clinical Samples Using Fluorogenic Probes Based on Oligonucleotide Gated Nanoporous Anodic Alumina Films.

In this work, fluorogenic probes based on oligonucleotide capped nanoporous anodic alumina films are developed for specific and sensitive detection of human papilloma virus (HPV) DNA. The probe consists of anodic alumina nanoporous films loaded with the fluorophore rhodamine B (RhB) and capped with oligonucleotides bearing specific base sequences complementary to genetic material of different high-risk (hr) HPV types. Synthesis protocol is optimized for scale up production of sensors with high reproducibility. The sensors' surfaces are characterized by scanning electron microscopy (HR-FESEM) and atomic force microscopy (AFM) and their atomic composition is determined by energy dispersive X-ray spectroscopy (EDXS). Oligonucleotide molecules onto nanoporous films block the pores and avoid diffusion of RhB to the liquid phase. Pore opening is produced when specific DNA of HPV is present in the medium, resulting in RhB delivery, that is detected by fluorescence measurements. The sensing assay is optimized for reliable fluorescence signal reading. Nine different sensors are synthesized for specific detection of 14 different hr-HPV types in clinical samples with very high sensitivity (100%) and high selectivity (93-100%), allowing rapid screening of virus infections with very high negative predictive values (100%).

Oligonucleotide-capped nanoporous anodic alumina biosensor as diagnostic tool for rapid and accurate detection of Candida auris in clinical samples.

Candida auris has arisen as an important multidrug-resistant fungus because of several nosocomial outbreaks and elevated rates of mortality. Accurate and rapid diagnosis of C. auris is highly desired; nevertheless, current methods often present severe limitations and produce misidentification. Herein a sensitive, selective, and time-competitive biosensor based on oligonucleotide-gated nanomaterials for effective detection of C. auris is presented. In the proposed design, a nanoporous anodic alumina scaffold is filled with the fluorescent indicator rhodamine B and the pores blocked with different oligonucleotides capable of specifically recognize C. auris genomic DNA. Gate opening modulation and cargo delivery is controlled by successful DNA recognition. C. auris is detected at a concentration as low as 6 CFU/mL allowing obtaining a diagnostic result in clinical samples in one hour with no prior DNA extraction or amplification steps.

Identification of Off-Patent Compounds That Present Antifungal Activity Against the Emerging Fungal Pathogen Candida auris.

Candida auris is an emerging fungal pathogen of great concern among the scientific community because it is causing an increasing number of hospital outbreaks of difficult management worldwide. In addition, isolates from this species frequently present reduced susceptibility to azole and echinocandin drugs. For this reason, it is necessary to develop new antifungal strategies to better control the disease caused by this yeast. In this work, we screened drugs from the Prestwick chemical library, which contains 1,280 off-patent compounds that are already approved by the Food and Drug Administration, with the aim of identifying molecules with antifungal activity against C. auris. In an initial screening, we looked for drugs that inhibited the growth of three different C. auris strains and found 27 of them which it did so. Ten active compounds were selected to test the susceptibility profile by using the EUCAST protocol. Antifungal activity was confirmed for seven drugs with MICs ranging from 0.5 to 64 mg/L. Some of these drugs were also tested in combination with voriconazole and anidulafungin at sub-inhibitory concentrations. Our results suggest synergistic interactions between suloctidil and voriconazole with fractional inhibitory concentration index (FICI) values of 0.11 to 0.5 and between ebselen and anidulafungin (FICI, 0.12 to 0.44). Our findings indicate that drug repurposing could be a viable alternative to managing infections by C. auris.

Selective and Sensitive Probe Based in Oligonucleotide-Capped Nanoporous Alumina for the Rapid Screening of Infection Produced by Candida albicans.

A robust, sensitive, and time-competitive system to detect Candida albicans in less than 30 min in clinical samples based in capped nanoporous anodic alumina (NAA) is developed. In the proposed design, NAA pores are loaded with rhodamine B and then blocked with an oligonucleotide that is able to recognize C. albicans DNA. The capped material shows negligible cargo release, whereas dye delivery is selectively accomplished when genomic DNA from C. albicans is present. This procedure has been successfully applied to detect C. albicans in clinical samples from patients infected with this yeast. When compared with classical C. albicans detection methods, the proposed probe has a short assay time, high sensitivity and selectivity, demonstrating the high potential of this simple design for the diagnosis of infection produced by C. albicans.

Detection and treatment of Candida auris in an outbreak situation: risk factors for developing colonization and candidemia by this new species in critically ill patients.

BACKGROUND: Candida auris is an emerging, multidrug-resistant yeast causing hospital outbreaks. This study describes the first 24 months of the ongoing C. auris outbreak in our hospital and analyzes predisposing factors to C. auris candidemia/colonization. RESEARCH DESIGN AND METHODS: A 12-month prospective, case-controlled study was performed including a total of 228 patients (114 colonized/candidemia and 114 controls). Data from the first 79 candidemia episodes and 738 environmental samples were also analyzed. Definitive C. auris identification was performed by ITS sequencing. Antifungal susceptibility was carried out by EUCAST methodology. RESULTS: Polytrauma (32%), cardiovascular disease (25%), and cancer (17%) were the most common underlying condition in colonized/candidemia patients. Indwelling CVC (odds ratio {OR}, 13.48), parenteral nutrition (OR, 3.49), and mechanical ventilation (OR, 2.43) remained significant predictors of C. auris colonization/candidemia. C. auris was most often isolated on sphygmomanometer cuffs (25%) patient tables (10.2%), keyboards (10.2%), and infusion pumps (8.2%). All isolates were fully resistant to fluconazole (MICs >64 mg/L) and had significantly reduced susceptibility to voriconazole (GM, 1.8 mg/L). CONCLUSIONS: Predictor conditions to C. auris colonization/candidemia are similar to other Candida species. C. auris colonizes multiple patient's environment surfaces. All isolates are resistant to fluconazole and had significant reduced susceptibility to voriconazole.

Echinocandins Compared to Fluconazole for Candidemia of a Urinary Tract Source: A Propensity Score Analysis.

BACKGROUND: Whether echinocandins could be used to treat candidemia of a urinary tract source (CUTS) is unknown. We aimed to provide current epidemiological information of CUTS and to compare echinocandin to fluconazole treatment on CUTS outcomes. METHODS: A multicenter study of adult patients with candidemia was conducted in 9 hospitals. CUTS was defined as a candidemia with concomitant candiduria by the same organism associated with significant urological comorbidity. The primary outcome assessed was clinical failure (defined by 7-day mortality or persistent candidemia) in patients treated with either an echinocandin or fluconazole. A propensity score was calculated and then entered into a regression model. RESULTS: Of 2176 episodes of candidemia, 128 were CUTS (5.88%). Most CUTS cases were caused by Candida albicans (52.7%), followed by Candida glabrata (25.6%) and Candida tropicalis (16.3%). Clinical failure occurred in 7 patients (20%) treated with an echinocandin and in 15 (17.1%) treated with fluconazole (P = .730). Acute renal failure (adjusted odds ratio [AOR], 3.01; 95% confidence interval [CI], 1.01-8.91; P = .047) was the only independent factor associated with clinical failure, whereas early urinary tract drainage procedures (surgical, percutaneous, or endoscopic) were identified as protective (AOR, 0.08; 95% CI, .02-.31; P < .001). Neither univariate nor multivariate analysis showed that echinocandin therapy altered the risk of clinical failure. CONCLUSIONS: Initial echinocandin therapy was not associated with clinical failure in patients with CUTS. Notably, acute renal failure predicted worse outcomes and performing an early urologic procedure was a protective measure.

Initial use of echinocandins does not negatively influence outcome in Candida parapsilosis bloodstream infection: a propensity score analysis.

BACKGROUND: Concerns have arisen regarding the optimal antifungal regimen for Candida parapsilosis bloodstream infection (BSI) in view of its reduced susceptibility to echinocandins. METHODS: The Prospective Population Study on Candidemia in Spain (CANDIPOP) is a prospective multicenter, population-based surveillance program on Candida BSI conducted through a 12-month period in 29 Spanish hospitals. Clinical isolates were identified by DNA sequencing, and antifungal susceptibility testing was performed by the European Committee on Antimicrobial Susceptibility Testing methodology. Predictors for clinical failure (all-cause mortality between days 3 to 30, or persistent candidemia for ≥72 hours after initiation of therapy) in episodes of C. parapsilosis species complex BSI were assessed by logistic regression analysis. We further analyzed the impact of echinocandin-based regimen as the initial antifungal therapy (within the first 72 hours) by using a propensity score approach. RESULTS: Among 752 episodes of Candida BSI identified, 200 (26.6%) were due to C. parapsilosis species complex. We finally analyzed 194 episodes occurring in 190 patients. Clinical failure occurred in 58 of 177 (32.8%) of evaluable episodes. Orotracheal intubation (adjusted odds ratio [AOR], 2.81; P = .018) and septic shock (AOR, 2.91; P = .081) emerged as risk factors for clinical failure, whereas early central venous catheter removal was protective (AOR, 0.43; P = .040). Neither univariate nor multivariate analysis revealed that the initial use of an echinocandin-based regimen had any impact on the risk of clinical failure. Incorporation of the propensity score into the model did not change this finding. CONCLUSIONS: The initial use of an echinocandin-based regimen does not seem to negatively influence outcome in C. parapsilosis BSI.

Molecular identification and antifungal susceptibility of yeast isolates causing fungemia collected in a population-based study in Spain in 2010 and 2011.

We report the molecular identifications and antifungal susceptibilities of the isolates causing fungemia collected in the CANDIPOP population-based study conducted in 29 Spanish hospitals. A total of 781 isolates (from 767 patients, 14 of them having mixed fungemia) were collected. The species found most frequently were Candida albicans (44.6%), Candida parapsilosis (24.5%), Candida glabrata (13.2%), Candida tropicalis (7.6%), Candida krusei (1.9%), Candida guilliermondii (1.7%), and Candida lusitaniae (1.3%). Other Candida and non-Candida species accounted for approximately 5% of the isolates. The presence of cryptic species was low. Compared to findings of previous studies conducted in Spain, the frequency of C. glabrata has increased. Antifungal susceptibility testing was performed by using EUCAST and CLSI M27-A3 reference procedures; the two methods were comparable. The rate of fluconazole-susceptible isolates was 80%, which appears to be a decrease compared to findings of previous studies, explained mainly by the higher frequency of C. glabrata. Using the species-specific breakpoints and epidemiological cutoff values, the rate of voriconazole and posaconazole in vitro resistance was low (<2%). In the case of C. tropicalis, using the EUCAST procedure, the rate of azole resistance was around 20%. There was a correlation between the previous use of azoles and the presence of fluconazole-resistant isolates. Resistance to echinocandins was very rare (2%), and resistance to amphotericin B also was very uncommon. The sequencing of the hot spot (HS) regions from FKS1 or FKS2 genes in echinocandin-resistant isolates revealed previously described point mutations. The decrease in the susceptibility to fluconazole in Spanish isolates should be closely monitored in future studies.

[Changes in the epidemiology of fungaemia and fluconazole susceptibility of blood isolates during the last 10 years in Spain: results from the FUNGEMYCA study]. / Variación de la epidemiología de las fungemias y de la sensibilidad al fluconazol de los aislamientos de hemocultivos en los últimos 10 años en España: resultados del estudio FUNGEMYCA.

BACKGROUND: Recent epidemiological surveillance studies have reported an increase in fungaemia caused by non-Candida albicans species, as well as a decrease in fluconazole susceptibility. OBJECTIVES: To evaluate changes in the epidemiology of fungaemia in Spain comparing data from a new surveillance epidemiological study conducted in 2009 with a previous study carried out from 1997 to 1999 (Pemán J, et al. Eur J Clin Microbiol Infect Dis. 2005). METHODS: From January 2009 to February 2010, 44 Spanish hospitals participated in a prospective multicentre fungaemia surveillance study to ascertain whether there have been changes in the epidemiology and fluconazole susceptibility. Susceptibility was determined by the colorimetric method Sensititre Yeast One. Demographic and clinical data and the first isolate of each episode were gathered. RESULTS: A total of 1,377 isolates from 1,357 fungaemia episodes were collected, 46.7% from patients older than 64years and 8.6% from children less than 1 year old. C. albicans (44.7%), Candida parapsilosis (29.1%), Candida glabrata (11.5%), Candida tropicalis (8.2%), and Candida krusei (1.9%) were the most frequent species isolated. Distribution varied with the geographical area. C. albicans incidence has increased significantly in the last 10years in Cataluña (39.1 vs. 54.7%, P=0.03) and decreased in the Valencian Community (49.1 vs. 34.6%, P=0.002) and Extremadura (58.3 vs. 20%, P=0.01). Susceptibility to fluconazole was similar for all geographical areas, although resistance in C. albicans was ten times greater for patients aged more than 64years. The overall rate of fluconazole resistance (MIC > 32 mg/L) has decreased with respect to that obtained 10years ago (3.7 vs. 2.5%) mainly in C. albicans (3 vs. 1.6%). CONCLUSIONS: In the last ten years, species distribution and fluconazole susceptibility have not significantly changed, although a lower rate of fluconazole resistance has been observed. Species distribution varies with hospital, hospitalization Unit and geographical area.

[In vitro antifungal activity of micafungin]. / Actividad antifúngica in vitro de la micafungina.

BACKGROUND: Micafungin is a new and very useful pharmacological tool for the treatment of invasive mycoses with a wide antifungal spectrum for the most common pathogenic fungi. Micafungin is especially active against the genera Candida and Aspergillus. Its antifungal mechanism is based on the inhibition of the beta-1,3- D-glucan synthesis, an essential molecule for the cell wall architecture, with different con sequences for Candida and Aspergillus, being micafungin fungicide for the former and fungistatic for the latter. AIM: To describe the in vitro antifungal spectrum of micafungin based in the scientific and medical lite rature of recent years. METHODS: We have done a bibliographic retrieval using the scientific terms, "micafungin", "activity", "Candida", "Aspergillus", "fungi", "mycos*", "susceptibility", in PubMed/Medline from the National Library of Medicine de EE.UU. from 2005 to 2009. RESULTS: We can underline that most than 99% of Candida isolates are susceptible to < or = 2microg/ml of micafungin. MIC are very low (< or = 0.125microg/ml) for most clinical isolates of the species Candida albicans, Candida glabrata, Candida tropicalis and Candida krusei while Candida parapsilosis and Candida guilliermondii isolates are susceptible to anidulafungin concentrations < or = 2microg/ml. The activity of micafungin is excellent against those medical important species of Aspergillus. However, its activity is very low against Cryptococcus and the Zygomycetes. CONCLUSIONS: The excellent activity of micafungin has made this antifungal a first line therapeutic indication for candidemia and invasive candidiasis in non-neutropenic patients.

Actividad antifúngica in vitro de la micafungina / In vitro antifungal activity of micafungin

Antecedentes: La micafungina es una aportación farmacológica nueva y eficaz para el tratamiento de las micosis invasoras con un espectro antifúngico que engloba a los hongos patógenos más comunes, y especialmente a los géneros Candida y Aspergillus. Su mecanismo de acción se basa en la inhibición de la síntesis de β-1,3-D-glucano, molécula esencial para la pared fúngica. Este mecanismo tiene como consecuencia 2 tipos de acciones: una acción fungicida contra Candida y una acción fungistática contra Aspergillus y otros hongos filamentosos. Objetivo: Describir el espectro antifúngico in vitro de micafungina, tomando como base los datos publicados en los últimos años. Métodos: Se ha realizado una búsqueda bibliográfica mediante el empleo de los términos “micafungin”, “activity”, “Candida”, “Aspergillus”, “fungi”, “mycos*”, “susceptibility”, en la base de datos PubMed/Medline de la National Library of Medicine desde enero de 2006 hasta enero de 2009. Resultados: Destaca que más del 99% de los aislamientos de Candida son sensibles a concentraciones menores o iguales de 2 μg/ml de micafungina. Dentro de esta sensibilidad in vitro a la micafungina, las concentraciones mínimas inhibitorias observadas son más bajas para Candida albicans, Candida glabrata, Candida tropicalis y Candida krusei, mientras que son más elevadas para Candida parapsilosis y Candida guilliermondii. La actividad fue excelente frente a la mayoría de las especies de Aspergillus de interés médico. Sin embargo, su actividad es prácticamente nula contra Cryptococcus y los zigomicetos. Conclusiones: Esta excelente actividad antifúngica hace que la micafungina sea una indicación terapéutica de primera línea para el tratamiento de las candidemias y candidiasis invasoras en pacientes sin neutropenia (AU)

Background: Micafungin is a new and very useful pharmacological tool for the treatment of invasive mycoses with a wide antifungal spectrum for the most common pathogenic fungi. Micafungin is especially active against the genera Candida and Aspergillus. Its antifungal mechanism is based on the inhibition of the β-1,3- D-glucan synthesis, an essential molecule for the cell wall architecture, with different consequences for Candida and Aspergillus, being micafungin fungicide for the former and fungistatic for the latter. Aim: To describe the in vitro antifungal spectrum of micafungin based in the scientific and medical literature of recent years. Methods: We have done a bibliographic retrieval using the scientific terms, “micafungin”, “activity”, “Candida”, “Aspergillus”, “fungi”, “mycos*”, “susceptibility”, in PubMed/Medline from the National Library of Medicine de EE.UU. from 2005 to 2009. Results: We can underline that most than 99% of Candida isolates are susceptible to ≤ 2 μg/ml of micafungin. MIC are very low (≤ 0.125 μg/ml) for most clinical isolates of the species Candida albicans, Candida glabrata, Candida tropicalis and Candida krusei while Candida parapsilosis and Candida guilliermondii isolates are susceptible to anidulafungin concentrations ≤ 2 μg/ml. The activity of micafungin is excellent against those medical important species of Aspergillus. However, its activity is very low against Cryptococcus and the Zygomycetes. Conclusions: The excellent activity of micafungin has made this antifungal a first line therapeutic indication for candidemia and invasive candidiasis in non-neutropenic patients (AU)

[In vitro activity of amphotericin B and anidulafungin against Candida spp. biofilms]. / Actividad in vitro de la anfotericina B y la anidulafungina sobre biopelículas de Candida albicans y Candida tropicalis.

Invasive infections caused by Candida spp. are increasing worldwide and are becoming an important cause of morbidity and mortality in immunocompromised patients. A large number of manifestations of candidiasis are associated with the formation of biofilms on inert or biological surfaces. Candida spp. biofilms are recalcitrant to treatment with conventional antifungal therapies. The aim of this study was dual 1) to determine the prevalence of biofilm producers among clinical isolates from catheter (16 C. albicans ) and blood culture (2 C. albicans and 30 C. tropicalis), and 2) to determine the activity of amphotericin B and anidulafungin against C. albicans and C. tropicalis biofilms of 24 and 48 hours of maturation. Biofilms were developed using a 96-well microtitre plate model and production and activity of antifungal agents against biofilms were determined by the tetrazolium (XTT) reduction assay. Of catheter and blood isolates, 62.5 and 56.25%, respectively, produced biofilms. By species, 68.42% of C. albicans and 53.33% of C. tropicalis were biofilm producers. C. albicans biofilms showed more resistance to amphotericin B and anidulafungin than their planktonic counterparts. Complete killing of biofilms was never achieved, even at the highest concentrations of the drugs tested. Anidulafungin displayed more activity than amphotericin B against C. albicans biofilms of 24 hours of maturation (GM MIC 0.354 vs. 0.686 microg/ml), but against C. tropicalis biofilms amphotericin B was more active (GM MIC 11.285 vs. 0.476 microg/ml). In contrast, against biofilms with 48 hours maturation, amphotericin B was more active against both species.

Procedimientos de diagnóstico microbiológico de las micosis y estudios de sensibilidad a los antifúngicos / Microbiological procedures for diagnosing mycoses and for antifungal susceptibility testing

Las infecciones fúngicas constituyen un problema diagnóstico y terapéutico de interés creciente debido, ante todo, al incremento y gravedad de las infecciones diseminadas en pacientes inmunodeprimidos. Los métodos diagnósticos basados en el cultivo son lentos y con sensibilidad insuficiente, por lo que se están desarrollando métodos diagnósticos basados en la detección de componentes genéticos, antigénicos o metabólicos específicos de los hongos, que permiten un diagnóstico y un tratamiento dirigido precoces. Por otra parte, se han estandarizado métodos para el estudio de la sensibilidad de los hongos a los antifúngicos, reproducibles y adaptables a un laboratorio asistencial, que permiten la detección de resistencias in vitro que se correlacionan con peor evolución clínica. En este trabajo revisamos los principales procedimientos microbiológicos para el diagnóstico de las infecciones causadas por hongos y los métodos desarrollados para los estudios de sensibilidad a los antifúngicos (AU)

Fungal infections are a diagnostic and therapeutic problem of increasing concern due to the frequency and severity of disseminated infection in immunocompromised patients. Culture-based methods are characteristically slow and have poor sensitivity; hence, other methods, based on the detection of fungus-specific genetic, antigenic and metabolic components are being developed to enable early diagnosis and specific treatment. Moreover, reproducible antifungal susceptibility methods that can be adapted for use in clinical laboratories have been standardized to allow in vitro detection of resistance, which correlates with a less favorable clinical outcome. In this paper we review the main microbiological procedures available for the diagnosis of fungal infections and for antifungal susceptibility testing (AU)

Blastoschizomyces capitatus infection in patients with leukemia: report of 26 cases.

Twenty-six cases of Blastoschizomyces capitatus infection were diagnosed in 25 patients at 7 tertiary care hematology units in Spain over a 10-year period. Most patients (92%) had acute leukemia and developed infection during a period of severe and prolonged neutropenia. Two patients had esophagitis, and the rest had invasive infection. Fungemia (20 cases) was a common finding, with frequent visceral dissemination. The 30-day mortality associated with this infection was 52%, compared with 57% among patients with systemic infection. In a univariate analysis, the following 3 variables had a positive impact on 30-day survival: removal of the central venous catheter within 5 days after the onset of infection (P=.02), a good performance status (P=.003), and receipt of systemic prophylactic or empirical antifungal therapy before infection onset (P=.006). Outcome for neutropenic patients with B. capitatus infection is still poor. Rapid removal of the central venous catheter and novel antifungal therapies are recommended for treatment of this rare infection.