Candida infections of the genitourinary tract

Prevalence and treatment of sexually transmitted infections in men followed by urologists in Germany - a cross sectional study with 347,090 men

Aim: The goal of this retrospective analysis was to study the prevalence and treatment of the most common sexually transmitted infections (STI) in men followed by urologists in Germany. Methods: This study included a total of 347,090 men followed in 71 urology practices in Germany between 2013 and 2015. The first outcome was the prevalence of individuals diagnosed with STI between 2013 and 2015. The following eight types of STI infections were included in the analysis: chlamydial infection, gonococcal infection, anogenital warts, anogenital herpes infection, trichomoniasis, ulcus molle, phthiriasis, and syphilis. The second outcome was the prevalence of individuals with STI who received an appropriate therapy within 90 days of their initial STI diagnosis. Results: The most frequent STI was anogenital warts (0.64%), whereas the least frequent STI was syphilis (0.03%). The median age at diagnosis ranged from 30.3 years for chlamydia infection to 47.5 years for trichomoniasis. The proportion of individuals receiving treatment was the highest for trichomoniasis (90.6%) and the lowest for anogenital warts (49.9%). Conclusions: Overall, approximately 1.25% of men followed in urology practices in Germany between 2013 and 2015 were diagnosed with at least one STI. Further research is needed to gain a better understanding of the factors potentially associated with the risk of being diagnosed with STI in this setting in Germany. Moreover, there is a need for enabling higher rates of diagnosis and thus treatment of infected persons.

Cranberry-derived proanthocyanidins induce a differential transcriptomic response within Candida albicans urinary biofilms

Candida albicans is one of the most common causes of hospital-acquired urinary tract infections (UTIs). However, azoles are poorly active against biofilms, echinocandins do not achieve clinically useful urinary concentrations, and amphotericin B exhibits severe toxicities. Thus, novel strategies are needed to prevent Candida UTIs, which are often associated with urinary catheter biofilms. We previously demonstrated that cranberry-derived proanthocyanidins (PACs) prevent C. albicans biofilm formation in an in vitro urinary model. To elucidate functional pathways unique to urinary biofilm development and PAC inhibition, we investigated the transcriptome of C. albicans in artificial urine (AU), with and without PACs. C. albicans biofilm and planktonic cells were cultivated with or without PACs. Genome-wide expression analysis was performed by RNA sequencing. Differentially expressed genes were determined using DESeq2 software; pathway analysis was performed using Cytoscape. Approximately 2,341 of 6,444 total genes were significantly expressed in biofilm relative to planktonic cells. Functional pathway analysis revealed that genes involved in filamentation, adhesion, drug response and transport were up-regulated in urinary biofilms. Genes involved in carbon and nitrogen metabolism and nutrient response were down-regulated. In PAC-treated urinary biofilms compared to untreated control biofilms, 557 of 6,444 genes had significant changes in gene expression. Genes downregulated in PAC-treated biofilms were implicated in iron starvation and adhesion pathways. Although urinary biofilms share key features with biofilms formed in other environments, many genes are uniquely expressed in urinary biofilms. Cranberry-derived PACs interfere with the expression of iron acquisition and adhesion genes within urinary biofilms.

[Inpatient candiduria: etiology, susceptibility to antifungal drugs and risk factors]

OBJECTIVE

Candida could become the second most frequent cause of nosocomial urinary tract infection. Although Candida albicans is the most important species, others have arisen as emerging pathogens. The aim of this study was to analyze the presence of candiduria in inpatients.

METHODS

We performed a retrospective study of Candida isolates from adult inpatient urocultures over five years, gathering and tabulating data on: the species; susceptibility to fluconazole, amphotericin B, and voriconazole (Vitek2, BioMerieux); presence of catheter; hospital department of origin; and patient age and sex.

RESULTS

We detected 289 yeast episodes, observing an annual increase: 134 (46.4%) were non-C. albicans yeasts, with 57 (19.7%) being Candida glabrata, 37 (12.8%) Candida tropicalis, 25 (8.6%) Candida parapsilosis, and 10 (3.5%) Candida lusitaniae. Most isolates derived from catheterized (240, 83.0%) and Internal Medicine Department (118, 40.8%) patients, observing an annual increase; 152 (52.6%) isolates were from males, and the mean age was >65 years. Susceptibility to antifungals was >85%.

CONCLUSIONS

Inpatient urocultures should include data on the presence of Candida, which is more prevalent in Internal Medicine Department inpatients, in those with urinary catheter, and in over 65-year-olds. Almost half of the isolates were non-C. albicans yeasts, and we recommend complete identification of the species involved.

Epitope unmasking in vulvovaginal candidiasis is associated with hyphal growth and neutrophilic infiltration

Vaginal candidiasis is a common disorder in women of childbearing age, caused primarily by the dimorphic fungus Candida albicans. Since C. albicans is a normal commensal of the vaginal mucosa, a long-standing question is how the fungus switches from being a harmless commensal to a virulent pathogen. Work with human subjects and in mouse disease models suggests that host inflammatory processes drive the onset of symptomatic infection. Fungal cell wall molecules can induce inflammation through activation of epithelial and immune receptors that trigger pro-inflammatory cytokines and chemokines, but pathogenic fungi can evade recognition by masking these molecules. Knowledge about which cell wall epitopes are available for immune recognition during human infection could implicate specific ligands and receptors in the symptoms of vaginal candidiasis. To address this important gap, we directly probed the surface of fungi present in fresh vaginal samples obtained both from women with symptomatic Candida vaginitis and from women that are colonized but asymptomatic. We find that the pro-inflammatory cell wall polysaccharide β-glucan is largely masked from immune recognition, especially on yeast. It is only exposed on a small percentage of hyphal cells, where it tends to co-localize with enhanced levels of chitin. Enhanced β-glucan availability is only found in symptomatic patients with strong neutrophil infiltration, implicating neutrophils as a possible driver of these cell wall changes. This is especially interesting because neutrophils were recently shown to be necessary and sufficient to provoke enhanced β-glucan exposure in C. albicans, accompanied by elevated immune responses. Taken together, our data suggest that the architecture of C. albicans cell wall can be altered by environmental stress during vaginal candidiasis.

Antifungal Activity and Mechanism of Action of the Co(III) Coordination Complexes With Diamine Chelate Ligands Against Reference and Clinical Strains of Candida spp

Although many antifungal agents are available in clinical treatment, increasing resistance of fungi, especially Candida species, to the available drugs requires the development of new safe and non-toxic compounds with novel modes of action as effective treatment against resistant microorganisms. Cobalt complexes are very interesting and attractive as potential candidates with antimicrobial activity. Their therapeutic uses as antiviral, antibacterial antifungal, antiparasitic, antitumour, transferrin transporters, and anti-inflammatory agents are being intensively investigated. In this study we examined the antifungal activity of Co(III) complexes with diamine chelate ligands against a broad spectrum of Candida species. Minimum inhibitory concentration was determined by the microbroth dilution method and with serial passaging assay; the synergistic antimicrobial activity of the tested complexes combined with two antifungal drugs (ketoconazole and amphotericin B) was made by checkerboard assay. The effects of Co(III) complexes on yeast cell morphology were studied by optical and transmission electron microscopy. The mode of action of Co(III) complexes on the yeast cell wall (sorbitol assay) and cell membrane (ergosterol assay) were investigated. The cytotoxic effects of the tested compounds on red blood cells and the human keratinocyte (HaCaT) cell line were also evaluated. The analyzed compounds revealed significant antifungal activity for selected strains of Candida species; [CoCl₂(dap)₂]Cl (1) and [CoCl₂(en)₂]Cl (2) were more effective than ketoconazole. Its probable mechanism of action did not involve the cell wall or ergosterol binding. However, the checkerboard assay showed, that the antifungal activity of ketoconazole increased in combination with the tested complexes of Co(III). Our results suggest that both diamine complexes with Co(III) analogs caused damage to mitochondrial membrane or the membrane of the endoplasmic reticulum. The effect was observed by transmission electron microscope. Co(III) complexes with diamine chelate ligands are non-toxic at concentrations active against Candida species. This study provides new data on potential antifungal drugs, especially against Candida species.

Factors Influencing Functional Heterogeneity in Human Mucosa-Associated Invariant T Cells

Mucosa-associated invariant T (MAIT) cells are unconventional innate-like T cells that recognize microbial riboflavin metabolites presented by the monomorphic MHC class I-related (MR1) molecule. Despite the high level of evolutionary conservation of MR1 and the limited diversity of known antigens, human MAIT cells and their responses may not be as homogeneous as previously thought. Here, we review recent findings indicating that MAIT cells display microbe-specific response patterns with multiple layers of heterogeneity. The natural killer cell receptor CD56 marks a MAIT cell subset with distinct response profile, and the T cell receptor β-chain diversity influences responsiveness at the single cell level. The MAIT cell tissue localization also influences their response profiles with higher IL-17 in tissue-resident MAIT cells. Furthermore, there is emerging evidence that the type of antigen-presenting cells, and innate cytokines produced by such cells, influence the quality of the ensuing MAIT cell response. On the microbial side, the expression patterns of MR1-presented antigenic and non-antigenic compounds, expression of other bioactive microbial products, and of innate pattern recognition ligands all influence downstream MAIT cell responses. These recent findings deepen our understanding of MAIT cell functional diversity and adaptation to the type and location of microbial challenge.

Contribution of TLR2 pathway in the pathogenesis of vulvovaginal candidiasis

Candida albicans is the prevalent etiological agent in acute vulvovaginal infection and the most severe chronic condition known as recurrent vulvovaginal candidiasis (VVC). A critical role of local innate immunity in defense and pathogenesis of vaginal infection by Candida is proposed. The fungal recognition by the innate immune receptor is an essential step for the induction of local responses including cytokines and antimicrobial peptides (AMPs) production for host protection. Using TLR2-deficient mice, we characterized the early innate immune response during VVC. Intravaginal challenge of TLR2-/- mice with C. albicans demonstrated that in response to the initial massive penetration, a strong local inflammatory reaction with recruitment of polymorphonuclear neutrophils was developed. Both interleukin 1β (IL1β)-regarded as the hallmark of VVC immunopathogenesis-and IL6 were increased in vaginal lavage. Murine beta defensin 1 (mBD1), a constitutive AMP with fungicidal and chemotactic activity, was significantly upregulated in wild type (WT) animals in response to infection. Interestingly, in the absence of TLR2 recognition, levels of mBD1 RNA more than twice higher than those in WT infected animals were observed. Interestingly, our results demonstrate that TLR2 signaling is important to control the fungal burden in the vaginal tract. These finding provide new evidence about the role of this innate receptor during VVC.

Lectins as Promising Therapeutics for the Prevention and Treatment of HIV and Other Potential Coinfections

Human immunodeficiency virus-acquired immunodeficiency syndrome (HIV/AIDS) remains a global health problem. Current therapeutics specifically target the viral pathogen at various stages of its life cycle, although complex interactions between HIV and other pathogenic organisms are evident. Targeting HIV and concomitant infectious pathogens simultaneously, both by therapeutic regimens and in prevention strategies, would help contain the AIDS pandemic. Lectins, a ubiquitous group of proteins that specifically bind glycosylated molecules, are interesting compounds that could be used for this purpose, with demonstrated anti-HIV properties. In addition, potential coinfecting pathogens, including other enveloped viruses, bacteria, yeasts and fungi, and protozoa, display sugar-coated macromolecules on their surfaces, making them potential targets of lectins. This review summarizes the currently available findings suggesting that lectins should be further developed to simultaneously fight the AIDS pandemic and concomitant infections in HIV infected individuals.

Tetraglochin andina Ciald.: A medicinal plant from the Argentinean highlands with potential use in vaginal candidiasis

ETHNOPHARMACOLOGICAL RELEVANCE

The Argentinean medicinal plant Tetraglochin andina Ciald, formerly classified as T. cristatum (Britton) Rothm is used in traditional medicine by inhabitants from Argentinean northwestern highlands (Puna) to treat candidiasis and as anti-inflammatory.

AIM OF THE STUDY

To assess the potential of the crude drug as an anti-Candida agent with anti-inflammatory properties. The bioactivity and phytochemical composition of a dry extract of the plant was investigated.

MATERIAL AND METHODS

The pharmacognostic description of the crude drug is carried out for the first time, including macroscopic and microscopic examinations of the different organs, physicochemical and extractive values (petroleum ether-, ethanol- and water-soluble). The dry extract from T. andina was evaluated as antifungal against pathogenic Candida sp. and Saccharomyces cerevisiae isolated from vaginal infections and reference strains, by the macrodilution and microdilution assays. The normal vaginal microbiome in women is characterized by the dominance of lactic acid-producing bacteria, mainly Lactobacillus spp. The effect of T. andina extract on Lactobacillus strains was also assayed. The inhibitory effect on proinflammatory enzymes (cyclooxygenase, lipoxygenase and phospholipase A₂) and antioxidant capacity was studied. The chemical profile was analyzed by HPLC-ESI-MS.

RESULTS

The hydroalcoholic extract inhibited the growth of all yeasts with Minimal Inhibitory Concentration (MIC) values between 12.5 and 400 µg GAE/mL and the MIC values on Lactobacillus were higher than the MIC values against Candida isolates ( > 400 µg GAE/mL). These results indicate that the hydroalcoholic extract could be used without affecting the normal microbiota of vaginal fluid. The extract showed antioxidant activity and could modulate the inflammatory process by three pathways (sPLA₂, COX-2, LOX). The plant extract contained high total phenolic levels (386.9±1.7 mg GAE/g dry extract) and flavonoid levels (260.4±2.7 mg GAE/g dry extract). Fifty phenolic compounds were identified by HPLC-ESI-MS. They were mainly hydrolysable and condensed tannins. The dry extract was chemically and biologically stable during one year at room temperature or 4 °C.

CONCLUSIONS

The presence of anti-Candida and anti-inflammatory activities in Tetraglochin andina extracts give support to their traditional use for treating conditions associated with microorganism infections and inflammatory process in humans. This plant preparation could be used to design phytopharmaceutical preparations to inhibit yeast growth and moderate the inflammatory and oxidative process.

Fighting biofilms with lantibiotics and other groups of bacteriocins

Biofilms are sessile communities of bacteria typically embedded in an extracellular polymeric matrix. Bacterial cells embedded in biofilms are inherently recalcitrant to antimicrobials, compared to cells existing in a planktonic state, and are notoriously difficult to eradicate once formed. Avenues to tackle biofilms thus far have largely focussed on attempting to disrupt the initial stages of biofilm formation, including adhesion and maturation of the biofilm. Such an approach is advantageous as the concentrations required to inhibit formation of biofilms are generally much lower than removing a fully established biofilm. The crisis of antibiotic resistance in clinical settings worldwide has been further exacerbated by the ability of certain pathogenic bacteria to form biofilms. Perhaps the most notorious biofilm formers described from a clinical viewpoint have been methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Gardnerella vaginalis and Streptococcus mutans, the latter of which is found in oral biofilms. Due to the dearth of novel antibiotics in recent decades, compounded by the increasing rate of emergence of resistance amongst pathogens with a propensity for biofilm formation, solutions are urgently required to mitigate these crises. Bacteriocins are a class of antimicrobial peptides, which are ribosomally synthesised and often are more potent than their antibiotic counterparts. Here, we review a selection of studies conducted with bacteriocins with the ultimate objective of inhibiting biofilms. Overall, a deeper understanding of the precise means by which a biofilm forms on a substrate as well as insights into the mechanisms by which bacteriocins inhibit biofilms is warranted.

Mechanisms of antimicrobial resistance among hospital-associated pathogens

INTRODUCTION

The introduction of antibiotics revolutionized medicine in the 20th-century permitting the treatment of once incurable infections. Widespread use of antibiotics, however, has led to the development of resistant organisms, particularly in the healthcare setting. Today, the clinician is often faced with pathogens carrying a cadre of resistance determinants that severely limit therapeutic options. The genetic plasticity of microbes allows them to adapt to stressors via genetic mutations, acquisition or sharing of genetic material and modulation of genetic expression leading to resistance to virtually any antimicrobial used in clinical practice. Areas covered: This is a comprehensive review that outlines major mechanisms of resistance in the most common hospital-associated pathogens including bacteria and fungi. Expert commentary: Understanding the genetic and biochemical mechanisms of such antimicrobial adaptation is crucial to tackling the rapid spread of resistance, can expose unconventional therapeutic targets to combat multidrug resistant pathogens and lead to more accurate prediction of antimicrobial susceptibility using rapid molecular diagnostics. Clinicians making treatment decisions based on the molecular basis of resistance may design therapeutic strategies that include de-escalation of broad spectrum antimicrobial usage, more focused therapies or combination therapies. These strategies are likely to improve patient outcomes and decrease the risk of resistance in hospital settings.

Mannose-Binding Lectin Gene Polymorphism and Its Association with Susceptibility to Recurrent Vulvovaginal Candidiasis

Recurrent vulvovaginal candidiasis (RVVC) is a common illness influencing childbearing women worldwide. Most women suffering from RVVC develop infection without specified risk factors. Mannose-binding lectin (MBL) is an important component of innate immune defense against Candida infection. Innate immunity gene mutations and polymorphisms have been suggested to play a role in susceptibility to RVVC. This study aimed to investigate the association between MBL 2 gene exon 1 codon 54 polymorphism and susceptibility to RVVC in childbearing women. Whole blood and serum samples were obtained from 59 RVVC cases and 59 controls. MBL serum level was measured by enzyme-linked immune-sorbent assay (ELISA). MBL2 exon 1 codon 54 polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). It was shown that MBL serum level was nonsignificantly different between RVVC cases and controls. The risk of RVVC was 3 times higher in those carrying MBL2 exon 1 codon 54 variant allele (B). It could be concluded that the carrying of MBL2 exon 1 codon 54 variant allele (B) was shown to be a risk factor for RVVC in childbearing women.

Structure-activity relationship studies of ultra-short peptides with potent activities against fluconazole-resistant Candida albicans

Vulvovaginal candidiasis (VVC) is a genital fungal infection afflicting approximately 75% of women globally and is primarily caused by the yeast Candida albicans. The extensive use of fluconazole, the first-line antifungal drug of choice, has led to the emergence of fluconazole-resistant C. albicans, creating a global clinical concern. This, coupled to the lack of new antifungal drugs entering the market over the past decade, has made it imperative for the introduction of new antifungal drug classes. Peptides with antifungal properties are deemed potential drug candidates due to their rapid membrane-disrupting mechanism of action. By specifically targeting and rapidly disrupting fungal membranes, they reduce the chances of resistance development and treatment duration. In a previous screening campaign involving an antimicrobial peptide library, we identified an octapeptide (IKIKIKIK-NH₂) with potent activity against C. albicans. Herein, we report a structure-activity relationship study on this peptide with the aim of designing a more potent peptide for further development. The lead peptide was then tested against a panel of fluconazole-resistant C. albicans, subjected to a fungicidal/static determination assay, a human dermal fibroblast viability assay and a homozygous profiling assay to gain insights into its mechanism of action and potential for further development as a topical antifungal agent.

Time-Kill Kinetics of Rezafungin (CD101) in Vagina-Simulative Medium for Fluconazole-Susceptible and Fluconazole-Resistant Candida albicans and Non-albicans Candida Species

Background

While echinocandins demonstrate excellent efficacy against Candida species in disseminated infections and demonstrate potent minimal inhibitory concentration (MIC) values under standard susceptibility testing conditions, investigation under conditions relevant to the vaginal environment was needed. We assessed the antifungal activity and time-kill kinetics of the novel echinocandin rezafungin (formerly CD101) under such conditions, against Candida species relevant to vulvovaginal candidiasis (VVC).

Methods

Susceptibility testing of fluconazole-susceptible and fluconazole-resistant C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei was performed in RPMI at pH 7.0 and in vagina-simulative medium (VSM) at pH 4.2 for topical rezafungin, terconazole, fluconazole, and amphotericin B. Time-kill kinetics were evaluated for rezafungin and terconazole at 2, 8, 32, and 128 μg/ml over 72 hours.

Results

Rezafungin MIC values were the same or 2-fold higher in VSM/pH 4.2 versus RPMI/pH 7.0. Some C. albicans terconazole MIC values were lower, but most were significantly higher in VSM than in RPMI. Rezafungin was fungicidal against 11/14 strains and near-fungicidal against the others. Terconazole (128 μg/ml) was fungicidal against C. krusei and near-fungicidal against susceptible C. parapsilosis but fungistatic versus all other strains evaluated.

Conclusion

Rezafungin retained anti-Candida activity and fungicidal activity under in vitro conditions relevant to VVC.

Candiduria in kidney transplant recipients: Is antifungal therapy useful?

A French single-centre retrospective study between 2010 and 2014 was undertaken to assess candiduria's incidence in kidney transplant recipients (KTR), and the use and impact of antifungal treatment on outcome. Candiduria was defined as a urine culture with ≥10³  cfu/mL of Candida species. Candiduria clearance, severe complications and death rates were estimated by Kaplan-Meier methods and the effect of treatment by Cox models. 52/1223 (4.3%) KTR had ≥1 episode of candiduria, 42 (81%) were females, 18 (35%) had diabetes, with an incidence of 2.3/100 person-year of follow-up. Candiduria was asymptomatic in 51 (98%) patients. Candida glabrata was the most frequent pathogen identified. Overall fungal clearance rate was 89%. Antifungal therapy was initiated in only 14 episodes (12%), according to guidelines. Three patients (6%) developed severe complications in the first 2 weeks after transplantation, and 8 (15%) died. Antifungal treatment had no impact on candiduria clearance (HR, 0.6; 95% CI, 0.3-1.1; P = .10), on recurrence rate (HR, 0.5; 95% CI, 0.1-2.3; P = .41) and on the risk of severe complications or death (HR, 1.1; 95% CI, 0.3-4.8; P = .89). Candiduria is rare and usually asymptomatic among KTR. Candiduria management in the immediate post-transplant period deserves careful attention.

Molecular identification of Candida species from urinary infections in Honduras

BACKGROUND

Candiduria is a common infection among hospitalised patients. Although the clinical relevance of yeasts in urine is not clearly defined, fungal urinary tract infections have increased significantly in the last decades, becoming a growing public health problem. Candida albicans is the most commonly reported species in urinary infections, although other species of the genus are becoming particularly important, because some of them are linked with resistance to antifungal drugs.

AIMS

This study aimed to evaluate the frequency of Candida species causing candiduria in a hospital in Honduras.

METHODS

A simple and cost-effective PCR-RFLP approach was used, by amplifying a partial sequence of the ribosomal ITS1-ITS2 region and a subsequent digestion with the enzyme MspI.

RESULTS

During 2016, an analysis was performed on 73 urine samples from patients of different ages. Seven species were found. Candida albicans/dubliniensis was the most frequent species (30%); Candida glabrata (28.8%) was the most isolated among the rest of the species. Candida kefyr was the least frequent species found (2.5%).

CONCLUSIONS

This study shows, for the first time in Honduras, the frequency of the Candida species isolated from urine using PCR-RFLP for their identification. This approach could be applied in future epidemiological studies at local and national level.

Chitosan Loaded into a Hydrogel Delivery System as a Strategy to Treat Vaginal Co-Infection

Polymeric hydrogels are common dosage forms designed for the topical administration of antimicrobial drugs to treat vaginal infections. One of the major advantages of using chitosan in these formulations is related to the intrinsic and broad antimicrobial activity exerted on bacteria and fungi by this natural polymer. Most vaginal yeast infections are caused by the pathogenic fungus Candida albicans. However, despite the anti-Candida activity towards and strains susceptibility to low molecular weight chitosan being documented, no information is available regarding the antimicrobial efficacy of mixed hydrogels in which chitosan is dispersed in a polymeric matrix. Therefore, the aim of the study is to evaluate the anti-Candida activity against eight different albicans and non-albicans strains of a mixed hydroxypropyl methylcellulose (HPMC)/chitosan hydrogel. Importantly, chitosan was dispersed in HPMC matrix either assembled in nanoparticles or in a monomolecular state to eventually correlate any variation in terms of rheological and mucoadhesive properties, as well as anti-Candida activity, with the chitosan form. Hydrogels containing 1% w/w chitosan, either as free polymer chain or assembled in nanoparticles, showed an improved mucoadhesiveness and an anti-Candida effect against all tested albicans and non-albicans strains. Overall, the results demonstrate the feasibility of preparing HPMC/CS mixed hydrogels intended for the prevention and treatment of Candida infections after vaginal administration.

Efflux pumps genes of clinical origin are related to those from fluconazole-resistant Candida albicans isolates from environmental water

Efflux pumps coded for by CDR1, CDR2, FLU1 and MDR1 genes could be responsible for the observed resistant phenotypes in azole-resistant Candida albicans from environmental water. This was demonstrated for clinical isolates. The aim of this study was to determine the presence and genetic similarity between efflux pump genes from clinical and environmental C. albicans isolates. Yeasts were isolated and identified using 26S rRNA gene sequencing. Disk diffusion tests were conducted. PCR was used to detect the presence of efflux genes. The fragments were sequenced and subjected to BLAST and subsequent phylogenetic analysis. Thirty seven C. albicans were identified from five selected rivers; Mooi River (19 isolates), Harts River (9 isolates), Marico River (5 isolates), Crocodile River (3 isolates) and Schoonspruit River (1 isolate). All the isolates were completely resistant to azoles. Efflux pump genes were detected in most (≥60%) of the isolates. Phylogenetic analysis showed high sequence similarity between sequences from environmental isolates and clinical isolates. Resistance to the azoles and the detection of efflux pump genes renders these antifungal agents ineffective. This is a major problem, particularly for the immune-compromised sector of the community of the North West Province and warrants further investigation.

Antimicrobial Activity of Cerium Oxide Nanoparticles on Opportunistic Microorganisms: A Systematic Review

An evaluation of studies of biologically active nanoparticles provides guidance for the synthesis of nanoparticles with the goal of developing new antibiotics/antifungals to combat microbial resistance. This review article focuses on the physicochemical properties of cerium oxide nanoparticles (CeNPs) with antimicrobial activity. Method. This systematic review followed the Guidelines for Transparent Reporting of Systematic Reviews and Meta-Analyses. Results. Studies have confirmed the antimicrobial activity of CeNPs (synthesized by different routes) using nitrate or chloride salt precursors and having sizes less than 54 nm. Conclusion. Due to the lack of standardization in studies with respect to the bacteria and CeNP concentrations assayed, comparisons between studies to determine more effective routes of synthesis are difficult. The mechanism of CeNP action likely occurs through oxidative stress of components in the cell membrane of the microorganism. During this process, a valence change occurs on the CeNP surface in which an electron is gained and Ce⁴⁺ is converted to Ce³⁺.

Candidalysin Drives Epithelial Signaling, Neutrophil Recruitment, and Immunopathology at the Vaginal Mucosa

Unlike other forms of candidiasis, vulvovaginal candidiasis, caused primarily by the fungal pathogen Candida albicans, is a disease of immunocompetent and otherwise healthy women. Despite its prevalence, the fungal factors responsible for initiating symptomatic infection remain poorly understood. One of the hallmarks of vaginal candidiasis is the robust recruitment of neutrophils to the site of infection, which seemingly do not clear the fungus, but rather exacerbate disease symptomatology. Candidalysin, a newly discovered peptide toxin secreted by C. albicans hyphae during invasion, drives epithelial damage, immune activation, and phagocyte attraction. Therefore, we hypothesized that Candidalysin is crucial for vulvovaginal candidiasis immunopathology. Anti-Candida immune responses are anatomical-site specific, as effective gastrointestinal, oral, and vaginal immunities are uniquely compartmentalized. Thus, we aimed to identify the immunopathologic role of Candidalysin and downstream signaling events at the vaginal mucosa. Microarray analysis of C. albicans-infected human vaginal epithelium in vitro revealed signaling pathways involved in epithelial damage responses, barrier repair, and leukocyte activation. Moreover, treatment of A431 vaginal epithelial cells with Candidalysin induced dose-dependent proinflammatory cytokine responses (including interleukin 1α [IL-1α], IL-1β, and IL-8), damage, and activation of c-Fos and mitogen-activated protein kinase (MAPK) signaling, consistent with fungal challenge. Mice intravaginally challenged with C. albicans strains deficient in Candidalysin exhibited no differences in colonization compared to isogenic controls. However, significant decreases in neutrophil recruitment, damage, and proinflammatory cytokine expression were observed with these strains. Our findings demonstrate that Candidalysin is a key hypha-associated virulence determinant responsible for the immunopathogenesis of C. albicans vaginitis.

The Interface between Fungal Biofilms and Innate Immunity

Fungal biofilms are communities of adherent cells surrounded by an extracellular matrix. These biofilms are commonly found during infection caused by a variety of fungal pathogens. Clinically, biofilm infections can be extremely difficult to eradicate due to their resistance to antifungals and host defenses. Biofilm formation can protect fungal pathogens from many aspects of the innate immune system, including killing by neutrophils and monocytes. Altered immune recognition during this phase of growth is also evident by changes in the cytokine profiles of monocytes and macrophages exposed to biofilm. In this manuscript, we review the host response to fungal biofilms, focusing on how these structures are recognized by the innate immune system. Biofilms formed by Candida, Aspergillus, and Cryptococcus have received the most attention and are highlighted. We describe common themes involved in the resilience of fungal biofilms to host immunity and give examples of biofilm defenses that are pathogen-specific.

Yeast and Fertility: Effects of In Vitro Activity of Candida spp. on Sperm Quality

BACKGROUND

Candida spp. causes semen candidiasis, the most important sexually transmitted fungal infection; this microorganism affects male fertility potential and could alter oocyte fertilization. The in vitro effects of the yeasts Candida albicans and Candida glabrata and their soluble factors of fungal metabolism on semen quality were studied.

METHODS

Candida strains (2, 0.5 and 0.05 McF) and their soluble factors were incubated for 3 hr with selected spermatozoa. Conventional (Viability and motility) and functional parameters (Mitochondrial membrane potential, membrane integrity, detection of reactive oxygen species and DNA fragmentation) were quantified in 35 semen samples. In addition, human spermatozoa were incubated under capacitating conditions with Candida spp. and soluble factors. Finally, spermatozoa were incubated with mannose before incubation with either yeast to block sperm and yeast interaction. Data was analyzed using Friedman test, and p<0.05 was considered significant.

RESULTS

The conventional sperm parameters were statistically affected by the two yeast strains after 3 hr and their effect was maintained until the 24 hr incubation. However, the functional parameters were altered, this change was not statistically significant. Pretreatment of spermatozoa with mannose decreased the effect of Candida spp.

CONCLUSION

The presence of C. albicans or C. glabrata affects seminal parameters. The effect is related to incubation time and yeast concentration, it can be supposed that the yeast sperm interaction is mediated through the mannose sperm receptor.

Knockout of autophagy gene, ATG5 in mice vaginal cells abrogates cytokine response and pathogen clearance during vaginal infection of Candida albicans

The female reproductive tract (FRT) presents a unique challenge to the mucosal immune system as it needs to monitor constantly for the presence of opportunistic pathogens amidst its commensal flora. During infection, autophagy plays a critical role in pathogen clearance, presentation of antigens and production of pro-inflammatory cytokines. However, no information is available that describes the role of autophagy in mouse vaginal infection of Candida albicans. The objective of our study is to evaluate the effect of autophagy gene, ATG5 knockout in vaginal cells in response to vaginal C. albicans infection. Mice having knockout of ATG5 in the vaginal cells (PR-ATG5-KO mice) were infected intra-vaginally with the yeast form of Candida albicans. Vaginal lavages were collected once in a week until the infection was cleared. We detected the expression of autophagy marker genes (LC3, ATG5 and LAMP1) in the vaginal cells. We determined the levels of various cytokines (IL-1α, IL-1β, IL-6, IL-10, IL-17A, IL-22, IL-23p19, TNF-α and G-CSF) involved in anti-candida response. The levels of cytokines in the vaginal lavages were quantified using Aimplex Premixed analyte kit. The vaginal lavages were checked for polymorphonuclear leucocytes (PMNLs) infiltration. The candida clearance rate from the vaginal lumen was determined by Colony Forming Units (CFUs) assay. The results revealed that PR-ATG5-KO mice failed to induce the expression of LC3, ATG5 and LAMP1 indicating an impaired autophagy pathway. The levels of all the cytokines (except IL-10) in C. albicans infected PR-ATG5-KO mice were significantly reduced as compared to the wild type infected C57BL/6 mice. The number of PMNLs infiltrated into the vaginal lavages of infected PR-ATG5-KO mice was reduced. The clearance of C. albicans from the vaginal lumen was also considerably delayed in PR-ATG5-KO mice. In conclusion, the results revealed that impaired autophagy in vaginal cells influences host response during vaginal infection of C. albicans by affecting anti-Candida cytokine levels in the vaginal lavage resulting in reduction of pathogen clearance rate.

Identification and antifungal susceptibility of Candida species isolated from the urine of patients in a university hospital in Brazil

The aim of this study was to identify Candida spp. isolated from candiduria episodes at a tertiary hospital in the Midwest region of Brazil, and to determine their susceptibility profiles to antifungal compounds. From May 2011 to April 2012, Candida spp. isolated from 106 adult patients with candiduria admitted to the University Hospital of the Federal University of Mato Grosso do Sul were evaluated. Both, species identification and susceptibility testing with fluconazole-FLC, voriconazole-VRC, and amphotericin B-AmB were carried out using the Vitek 2. To discriminate species of the C. parapsilosis complex, a RAPD-PCR technique using the RPO2 primer was performed. From the total of 106 isolates, 42 (39.6%) C. albicans and 64 (60.4%) Candida non-albicans (CNA) - 33 C. tropicalis, 18 C. glabrata, 5 C. krusei, 4 C. parapsilosis sensu stricto, 2 C. kefyr, 1 C. lusitaniae, and 1 C. guilliermondii were identified. All isolates were susceptible to AmB and VRC, whereas all C. glabrata isolates presented either resistance (5.6%) or dose-dependent susceptibility (94.4%) to FLC. The study of Candida spp. and their resistance profiles may help in tailoring more efficient therapeutic strategies for candiduria.

Host Sensing by Pathogenic Fungi

The ability to cause disease extends from the ability to grow within the host environment. The human host provides a dynamic environment to which fungal pathogens must adapt to in order to survive. The ability to grow under a particular condition (i.e., the ability to grow at mammalian body temperature) is considered a fitness attribute and is essential for growth within the human host. On the other hand, some environmental conditions activate signaling mechanisms resulting in the expression of virulence factors, which aid pathogenicity. Therefore, pathogenic fungi have evolved fitness and virulence attributes to enable them to colonize and infect humans. This review highlights how some of the major pathogenic fungi respond and adapt to key environmental signals within the human host.

Recent advances in delivery of antifungal agents for therapeutic management of candidiasis

Candidiasis is a fungal infection caused by yeasts that belong to the genus Candida. There are over twenty species of Candida yeasts that can cause infection in humans, the most common of which is Candida albicans. Candida yeasts normally reside in the intestinal tract and can be found on mucous membranes and skin without causing infection; however, overgrowth of these organisms can cause symptoms to develop. Presence of other diseases that compromises the patient's immunity makes it more difficult to treat. Candidiasis is majorly divided into superficial infections (oral or vaginal) and systemic infections, also known as invasive candidiasis. The conventional therapeutic modalities used to treat candidiasis are associated with several side effects that limits the dose and dosing frequency. Development of novel drug delivery systems for reduction in dose and alleviation of side effects is an important strategy to improve the clinical efficacy and patient acceptability. This review gives a bird's eye view of the classification and current therapeutic regime of candidiasis. It presents the varied types of drug delivery systems that have been exploited for delivery of antifungal agents with measurable benefits. It also touches upon echinocandins a relatively new class of drugs that are amenable for translation into novel dosage forms with application against biofilm producing and fluconazole resistant strains contributing to a better therapeutic management of candidiasis.

Identification of Candida species isolated from vulvovaginitis using matrix assisted laser desorption ionization-time of flight mass spectrometry

Background and Purpose:

Vulvovaginal candidiasis (VVC) is a common problem in women. The purpose of this study was to identify Candida isolates by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) from women with vulvovaginitis that were referred to Ghaem Hospital, Mashhad, Iran.

Materials and Methods:

This study was conducted on 65 clinical samples isolated from women that were referred to Ghaem Hospital. All specimens were identified using phenotyping techniques, such as microscopy and culture on Sabouraud dextrose agar and corn meal agar. In addition, all isolates were processed for MALDI-TOF MS identification.

Results:

Out of the 65 analyzed isolates, 61 (94%) samples were recognized by MALDI-TOF MS. However, the remaining four isolates (6%) had no reliable identification. According to the results, C. albicans (58.5%) was the most frequently isolated species, followed by C. tropicalis (16.9%), C. glabrata (7.7%), C. parapsilosis (7.7%), and guilliermondii (3.1%).

Conclusion:

As the findings indicated, MALDI TOF MS was successful in the identification of clinical Candida species. C. albicans was identified as the most common Candida species isolated from the women with VVC. Moreover, C. tropicalis was the most common species among the non-albicans Candida species.

Nosocomial Candiduria in the Elderly: Microbiological Diagnosis

Candiduria is associated with high morbidity, mortality, and long hospitalization, involving high costs for the healthcare system. The use of increasingly aggressive treatments has prolonged the lives of patients susceptible to candiduria, namely the immunosuppressed, the premature, and the elderly. Our objective was to evaluate the incidence of nosocomial candiduria and the implicated species in hospitalized patients aged over 80 years old from three Spanish centers during 2012 and 2013. Urine samples received from these patients were cultured and analyzed by flow cytometry in search of leukocyturia, hematuria, proteinuria, and microbial nitrate reductase activity. The isolated yeast species were identified microscopically, by germ tube formation in serum, colony morphology after subculture onto CHROMagar Candida (Becton-Dickinson, UK), assimilation of carbon compounds ID32C (bioMérieux, France), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDITOF) (Bruker Daltonics, Germany) and, in case of inconsistency, by sequencing of the ITS regions of ribosomal DNA (ITS1-5, 8S-ITS2). Susceptibility tests were also performed. The incidence of candiduria in the elderly population was 10.3%. A total of 155 strains of yeasts were isolated. The predominant species was Candida albicans, followed by Candida glabrata and then Candida tropicalis. Several infrequent species were found; among them, the first isolate of candiduria-producing Candida pulcherrima described in the literature. Our finding should raise concerns about the elderly population, which is probably the most important risk group for candiduria in the present moment, and the emergence of unusual yeast species producing candiduria, which are resistant against the commonly used antifungal agents.

Induction of cyclooxygenase-2 gene by Candida albicans through EGFR, ERK, and p38 pathways in human urinary epithelium

In the present data, we found that Candida albicans (C. albicans) caused bladder epithelial cell morphology alteration, cell damage, and inflammatory responses, including cyclooxygenase-2 (COX-2) gene and protein expression as well as prostaglandin E2 accumulation. In addition, the molecular pathway underlying C. albicans-induced urothelial COX-2 gene expression was examined. Among MAPK pathways, phosphorylation of ERK1/2, p38, and JNK each increased following C. albicans infection for 12 h. However, C. albicans-induced COX-2 protein expression was inhibited by specific inhibitors of ERK and p38 (U0126 and SB203580) but not by JNK inhibitor SP600125. Additional evidence came from the increased amount of phosphorylated RSK that is the mutual downstream molecule of ERK1/2 and p38. Furthermore, phosphorylation of RSK protein was reduced by the ERK and p38 inhibitor, suggesting that the urothelial COX-2 gene was induced majorly though the ERK/p38-RSK pathway by C. albicans infection. We also found transcription factor CREB-1 showed increased binding to the COX-2 gene promoter by chromatin immunoprecipitation assay. Next, we used receptor inhibitors including Toll-like receptor (TLR)-Myd88 inhibitor ST2825, Dectin-Syk inhibitor Syk inhibitor, and epidermal growth factor receptor (EGFR) inhibitor PD168393 to identify which one was the main target associated with C. albicans binding. The results revealed that it was EGFR, recognized by C. albicans, that mostly mediated the ERK/p38-RSK pathway activation to induce COX-2 gene expression, but this was not the case for TLRs and Dectin receptors. In summary, these results demonstrated the EGFR-ERK/p38-RSK-CREB-1 pathway was involved significantly in the C. albicans-induced COX-2 expression in human urothelium.

SGLT2 inhibitors: are they safe?

Sodium-glucose linked transporter type 2 (SGLT2) inhibitors are a relatively new class of antidiabetic drugs with positive cardiovascular and kidney effects. The aim of this review is to present the safety issues associated with SGLT2 inhibitors. Urogenital infections are the most frequently encountered adverse events, although tend to be mild to moderate and are easily manageable with standard treatment. Although no increased acute kidney injury risk was evident in the major trials, the mechanism of action of these drugs requires caution when they are administered in patients with extracellular volume depletion or with drugs affecting renal hemodynamics. Canagliflozin raised the risk of amputations and the rate of fractures in the CANVAS trial, although more data are necessary before drawing definite conclusions. The risk of euglycemic diabetic ketoacidosis seems to be minimal when the drugs are prescribed properly. Regarding other adverse events, SGLT2 inhibitors do not increase the risk of hypoglycemia even when co-administered with insulin, but a decrease in the dose of sulphonylureas may be needed. The available data do not point to a causative role of SGLT2 inhibitors on malignancy risk, however, these drugs should be used with caution in patients with known hematuria or history of bladder cancer. SGLT2 inhibitors seem to be safe and effective in the treatment of diabetes but more studies are required to assess their long-term safety.

High prevalence of candiduria due to non-albicans Candida species among diabetic patients: A matter of concern?

BACKGROUND

Among the fungal pathogens, Candida species are the most common cause of urinary tract infection (UTI). Some predisposing factors such as diabetes mellitus, urinary retention, urinary stasis, renal transplantation, and hospitalization can increase the risk of candiduria. The aim of this cross-sectional study was to evaluate candiduria among type 2 diabetic patients and identification of the Candida isolates.

METHOD

Four hundred clean-catch midstream urine specimens were obtained from patients with type 2 diabetes mellitus. The specimens were centrifuged and the sediments were examined by direct examination and cultured on Sabouraud dextrose agar. The plates were incubated for 2-3 days at 35°C. The Candida colonies were counted and purified using CHROMagar Candida. The isolates were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system.

RESULTS

Of the 400 urine specimens, 40 (10%) had positive cultures for Candida species with a colony count of ≥1 × 10³ colony forming units (CFU)/mL. The frequencies of the Candida species were as follows: C. albicans (n = 19, 47.5%), C. glabrata (n = 15, 37.5%), C. kefyer (n = 4, 10%) and C. krusei (n = 2, 5%). Seventy-three (88%) of the patients with candiduria had hemoglobin A1c (HbA1c) levels above 7%.

CONCLUSION

The rate of candiduria was relatively high in type 2 diabetic patients and they were also suffering from a lack of proper blood glucose control. Although the frequency of non-albicans Candida species had not significantly higher than C. albicans, however, they obtained more from those with symptomatic candiduria.

[Candiduria! What now? : Therapy of urinary tract infections with Candida]

BACKGROUND

Yeasts are found in urine specimens relatively often, especially in the elderly and patients under treatment with broad spectrum antibiotics, i. e. especially in intensive care unit (ICU) patients. In some cases, the number of pathogens is very high, i. e. >10⁵/ml. The clinical relevance of detecting Candida in urine is difficult to assess. In the German S3 guidelines it is apodictically stated that an ascending infection of the urinary tract by yeasts does not occur but this may undoubtedly happen in certain instances in patients at risk, for example in the elderly, in diabetic persons and in the case of foreign bodies in the urinary tract. A hematogenous spread of yeasts can lead to pyelonephritis, which accompanies candiduria. In rare cases this can be induced by prostatitis and epididymitis. Therapy is indicated in all cases when a urological manipulation is planned, particularly those with injury to the mucosal barrier, in order to prevent an intraoperative spread of pathogens.

AIM

The antimicrobial agents suitable for therapy of candiduria are limited, namely flucytosine, amphotericin B, which is also used for irrigation and fluconazole.

MATERIAL AND METHODS

The in vitro effect of nitroxoline on 100 isolates of yeasts from urine was tested by an agar diffusion test.

RESULTS

Nitroxoline exerted a good activity against all yeast isolates.

DISCUSSION

The antibiotic nitroxoline has a good antifungal activity. It achieves high concentrations in urine and in addition, it is effective at low pH as well as against pathogens in biofilms, which most antimycotics cannot achieve. Hence, nitroxoline is suitable for termination of candiduria. Foreign bodies in the urinary tract, on which biofilms are formed, should be removed whenever possible.

Development and regulation of single- and multi-species Candida albicans biofilms

Candida albicans is among the most prevalent fungal species of the human microbiota and asymptomatically colonizes healthy individuals. However, it is also an opportunistic pathogen that can cause severe, and often fatal, bloodstream infections. The medical impact of C. albicans typically depends on its ability to form biofilms, which are closely packed communities of cells that attach to surfaces, such as tissues and implanted medical devices. In this Review, we provide an overview of the processes involved in the formation of C. albicans biofilms and discuss the core transcriptional network that regulates biofilm development. We also consider some of the advantages that biofilms provide to C. albicans in comparison with planktonic growth and explore polymicrobial biofilms that are formed by C. albicans and certain bacterial species.

The Candida albicans Inhibitory Activity of the Extract from Papaya (Carica papaya L.) Seed Relates to Mitochondria Dysfunction

The inhibitory activity of the papaya seed extract (PSE) on Candida albicans (C. albicans) was determined by turbidimetry method. The inhibitory mechanisms were also evaluated from the prospective of reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP) decrease, and the activities of four complex enzymes in mitochondria respiratory chain. Results obtained from this study indicated that the PSE exhibited an effective inhibitory activity on C. albicans and induced significant accumulation of ROS and collapse of MMP. The Complex I and Complex III exhibited continues significant decrease in mitochondrial enzyme activity assays, but the Complex II and Complex IV activities were not positively correlated. Furthermore, the GC-MS analysis demonstrated that the PSE represents a rich and high-purity source of benzyl isothiocyanate (BITC), which indicated the BITC may be responsible for the mitochondrial dysfunction.

Candida-Bacteria Interactions: Their Impact on Human Disease

Candida species are the most common infectious fungal species in humans; out of the approximately 150 known species, Candida albicans is the leading pathogenic species, largely affecting immunocompromised individuals. Apart from its role as the primary etiology for various types of candidiasis, C. albicans is known to contribute to polymicrobial infections. Polymicrobial interactions, particularly between C. albicans and bacterial species, have gained recent interest in which polymicrobial biofilm virulence mechanisms have been studied including adhesion, invasion, quorum sensing, and development of antimicrobial resistance. These trans-kingdom interactions, either synergistic or antagonistic, may help modulate the virulence and pathogenicity of both Candida and bacteria while uniquely impacting the pathogen-host immune response. As antibiotic and antifungal resistance increases, there is a great need to explore the intermicrobial cross-talk with a focus on the treatment of Candida-associated polymicrobial infections. This article explores the current literature on the interactions between Candida and clinically important bacteria and evaluates these interactions in the context of pathogenesis, diagnosis, and disease management.

Isolation, speciation and antifungal susceptibility testing of Candida isolates from various clinical specimens at a tertiary care hospital, Nepal

BACKGROUND

Candida species are responsible for various clinical infections ranging from mucocutaneous infection to life threatening invasive diseases along with increased resistance to antifungal drugs has made a serious concern. Resistance to antifungal agents has increased during the last decade. Thus, identification of Candida up to species level and its antifungal susceptibility testing has a paramount significance in the management of Candidal infections. The aim of the study was to speciate Candida species and to determine antifungal susceptibility pattern of Candida species to antifungal agents.

METHODS

A total of 100 consecutive Candida species were isolated from 1248 clinical specimens over 7 months period. Growths on Sabouraud dextrose agar were evaluated for colony appearance, macroscopic examination, Gram staining, germ tube test and urea hydrolysis test. Further, they were processed for Candida speciation on CHROMagar. Antifungal susceptibility testing was performed as recommended by Clinical and Laboratory Standards Institute (CLSI) M44-A document.

RESULTS

Out of 100 Candida isolates, Candida albicans (56%) was the most common species. Among the non-albicans Candida species, Candida tropicalis (20%) was the predominant isolate followed by Candida glabrata (14%). Regarding antifungal susceptibility pattern, Candida species were more susceptible to clotrimazole (82%) followed by fluconazole (64%) and miconazole (44%).

CONCLUSIONS

Candida albicans was the predominant species responsible for various Candidal infections. Among commonly used antifungal drugs clotrimazole, miconazole and fluconazole were most effective.

A Chitin-binding Protein Purified from Moringa oleifera Seeds Presents Anticandidal Activity by Increasing Cell Membrane Permeability and Reactive Oxygen Species Production

Candida species are opportunistic pathogens that infect immunocompromised and/or immunosuppressed patients, particularly in hospital facilities, that besides representing a significant threat to health increase the risk of mortality. Apart from echinocandins and triazoles, which are well tolerated, most of the antifungal drugs used for candidiasis treatment can cause side effects and lead to the development of resistant strains. A promising alternative to the conventional treatments is the use of plant proteins. M. oleifera Lam. is a plant with valuable medicinal properties, including antimicrobial activity. This work aimed to purify a chitin-binding protein from M. oleifera seeds and to evaluate its antifungal properties against Candida species. The purified protein, named Mo-CBP₂, represented about 0.2% of the total seed protein and appeared as a single band on native PAGE. By mass spectrometry, Mo-CBP₂ presented 13,309 Da. However, by SDS-PAGE, Mo-CBP₂ migrated as a single band with an apparent molecular mass of 23,400 Da. Tricine-SDS-PAGE of Mo-CBP₂ under reduced conditions revealed two protein bands with apparent molecular masses of 7,900 and 4,600 Da. Altogether, these results suggest that Mo-CBP₂ exists in different oligomeric forms. Moreover, Mo-CBP₂ is a basic glycoprotein (pI 10.9) with 4.1% (m/m) sugar and it did not display hemagglutinating and hemolytic activities upon rabbit and human erythrocytes. A comparative analysis of the sequence of triptic peptides from Mo-CBP₂ in solution, after LC-ESI-MS/MS, revealed similarity with other M. oleifera proteins, as the 2S albumin Mo-CBP₃ and flocculating proteins, and 2S albumins from different species. Mo-CBP₂ possesses in vitro antifungal activity against Candida albicans, C. parapsilosis, C. krusei, and C. tropicalis, with MIC₅₀ and MIC₉₀ values ranging between 9.45–37.90 and 155.84–260.29 μM, respectively. In addition, Mo-CBP₂ (18.90 μM) increased the cell membrane permeabilization and reactive oxygen species production in C. albicans and promoted degradation of circular plasmid DNA (pUC18) from Escherichia coli. The data presented in this study highlight the potential use of Mo-CBP₂ as an anticandidal agent, based on its ability to inhibit Candida spp. growth with apparently low toxicity on mammalian cells.

Phenotypic and genotypic characteristics of Candida albicans isolates from bloodstream and mucosal infections

The interaction of Candida albicans with the host is of a complex nature involving fungal factors and host's response. In this study, we concentrated on the phenotypic expression of virulence attributes and genotypic characteristics of C. albicans isolates from two distinct clinical entities of candidiasis-blood stream and vaginal infections, and the possible role of these factors. Hence, we conducted a comparative in vitro assessment of virulence characteristics, including adhesion to epithelial cells and HaCat cell line, biofilm formation, aspartic proteinases and phospholipase activity of 20 C. albicans isolates from patients with C. albicans bloodstream infection and 22 isolates from patients with C. albicans vaginitis. Further, we studied the epigenetic phenotypic switching of the strains and their ploidy, by flow cytometry and CHEF techniques. These studies indicated that although no overall differentiation between the isolates of the two groups (bloodstream infection and vaginitis) could be demonstrated, several characteristics were more specific to one of the groups than the other. While the strains from vaginal infection had higher capacity to adhere, the strains from patients with bloodstream infection had higher activity of phospholipase. Differences were also noted in phenotypic switching, with the strains from bloodstream infection revealing primarily the "white" type colonies, known to be more virulent, and had higher DNA content. This study is unique considering the concurrent comparison of isolates from different clinical entities, at the phenotypic and genotypic level.

Candiduria: Evidence-based approach to management, are we there yet?

Candiduria is considered one of the most controversial issues in patient management. Neither the diagnosis nor the optimal treatment options are standardized. This is further complicated by lack of defined laboratory criteria for diagnosis as most of the studies were set for bacterial rather than fungal urinary tract infection (UTI). Furthermore, since Candida species is a known commensal of the genitourinary tract its presence in the urine sample adds ambiguity to making a definitive diagnosis of candidal UTI. Guidelines for diagnosis and management of candiduria have changed considerably over the past decades. In 1960s, the condition was believed to be benign with no intervention required. However, over the years new dimensions were added to address the issues associated with candiduria until the latest Infectious Diseases Association of America (IDSA) guidelines were published in 2009, which indicated that there was an increase in the incidence of candiduria caused by more resistant non-Candida albicans species. Further complicating the issue is the observation that candiduria may be the only indicator of a more serious invasive candidiasis, especially in immunocompromised patients. Long-term urinary catheterization is considered to be the most significant risk factor for candiduria followed by antibiotic use and diabetes. Strategies for management are based on the evaluation of candiduria in the context of the clinical setting to determine its relevance and make an appropriate decision about the need for antifungal therapy. Fluconazole is the main drug used for its efficacy and least complications. Other options include bladder irrigation with amphotericin B, flucytosine or parenteral amphotericin B. Since azoles other than fluconazole and all echinocandins are poorly excreted in urine they have been found to be less effective in candiduric patients.

Prevalence of vaginitis in different age groups among females in Greece

Patients with vaginitis were classified into four groups: Group A (prepubertal under-aged females); Group B (pubertal under-aged females); Group C (reproductive age adult females); Group D (postmenopausal adult females). All vaginal specimens underwent microscopy, amine testing, Gram staining and culturing. Overall, 163 patients were included (33, 14, 81 and 35 patients, respectively). The most common infection was bacterial vaginosis (BV), followed by Ureaplasma infection, aerobic vaginitis (AV) and candidiasis. The most common AV-associated organism was Escherichia coli and the most common BV-associated organism was Gardnerella vaginalis. AV was more frequent in Group A, BV in Group C and Ureaplasma infections in Groups C/D. Decreased lactobacilli concentrations were associated with BV in fertile patients (Groups B-C). Although presentation of vaginitis is similar among females of different age in Greece, type and prevalence of pathogens differ. Normal vaginal flora changes are associated with higher risk of vaginitis in specific age groups. Impact Statement The worldwide incidence of reproductive tract infections has been increasing, with specific pathogens being associated with significant risk of morbidity and complications. However, literature data on the distribution of such infections in different age groups is limited. Therefore, the aim of this study was to provide data on the prevalence and causes of vaginitis in adult and non-adult females of all ages. This study has shown that although presentation of vaginitis is similar among females of different age groups and menstrual status in Greece, type and prevalence of responsible pathogens are different among groups. Changes in normal vaginal flora seem to be associated with higher risk of vaginitis in specific age-groups as well. These findings could contribute in adjusting diagnostic and therapeutic strategies for each age group according to the prevailing pathogens. Further research on antibiotic resistance and treatment outcomes for each age group should be conducted.