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FEMS Microbiology Reviews Mar 2012The incidence of infections caused by Candida species (candidosis) has increased considerably over the past three decades, mainly due to the rise of the AIDS epidemic,... (Review)
Review
The incidence of infections caused by Candida species (candidosis) has increased considerably over the past three decades, mainly due to the rise of the AIDS epidemic, an increasingly aged population, higher numbers of immunocompromised patients and the more widespread use of indwelling medical devices. Candida albicans is the main cause of candidosis; however, non-C. albicans Candida (NCAC) species such as Candida glabrata, Candida tropicalis and Candida parapsilosis are now frequently identified as human pathogens. The apparent increased emergence of these species as human pathogens can be attributed to improved identification methods and also associated with the degree of diseases of the patients, the interventions that they were subjected and the drugs used. Candida pathogenicity is facilitated by a number of virulence factors, most importantly adherence to host surfaces including medical devices, biofilm formation and secretion of hydrolytic enzymes (e.g. proteases, phospholipases and haemolysins). Furthermore, despite extensive research to identify pathogenic factors in fungi, particularly in C. albicans, relatively little is known about NCAC species. This review provides information on the current state of knowledge on the biology, identification, epidemiology, pathogenicity and antifungal resistance of C. glabrata, C. parapsilosis and C. tropicalis.
Topics: Animals; Antifungal Agents; Candida; Candida glabrata; Candida tropicalis; Candidiasis; Drug Resistance, Fungal; Humans
PubMed: 21569057
DOI: 10.1111/j.1574-6976.2011.00278.x -
Current Opinion in Microbiology Dec 2019The discovery in 2009 of a new species of yeast, Candida auris, heralded the arrival of a novel emerging human infectious disease. This review highlights the unique... (Review)
Review
The discovery in 2009 of a new species of yeast, Candida auris, heralded the arrival of a novel emerging human infectious disease. This review highlights the unique characteristics of C. auris that have lled to it being of public health concern worldwide, namely public health concern, namely its global emergence, its ability to cause nosocomial outbreaks in healthcare settings, its innate and emerging resistance to multiple antifungal drugs and its resilience in the face of hygiene and infection control measures. Genomic epidemiology has identified four emergences of C. auris marked by four clades of the pathogen. These clades of C. auris are genetically dissimilar and are associated with differential resistance to antifungal drugs, suggesting that they will continue to phenotypically diverge into the future. The global emergence of C. auris testifies to the unmapped nature of Kingdom Fungi, and represents a new nosocomial threat that will require enhanced infection control across diverse healthcare and community settings.
Topics: Candida; Candidiasis; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Fungal; Genetic Variation; Global Health; Humans
PubMed: 31279224
DOI: 10.1016/j.mib.2019.05.008 -
MicrobiologyOpen Aug 2018From 2009, Candida auris has emerged as a multidrug-resistant ascomycete yeast pathogen with the capacity for easy transmission between patients and hospitals, as well... (Meta-Analysis)
Meta-Analysis
From 2009, Candida auris has emerged as a multidrug-resistant ascomycete yeast pathogen with the capacity for easy transmission between patients and hospitals, as well as persistence on environmental surfaces. Its association with high mortalities, breakthrough and persistent candidaemia, inconsistencies in susceptibility testing results, misidentification by available commercial identification systems and treatment failure, complicates its management and detection. Within the last nine years, C. auris has been increasingly reported from far-Eastern Asia, the Middle East, Africa, Europe, South and North America with substantial fatalities and misidentification. Herein, I provide a systematic and thorough review of this emerging pathogen. Meta-analysis showed that at least 742 C. auris isolates have been reported in 16 countries, with most of these being from India (≥243), USA (≥232) and UK (≥103) (p-value = .0355) within 2013-2017. Most isolates were from males (64.76%) (p-value = .0329) and blood (67.48%) (p-value < .0001), with substantial crude mortality (29.75%) (p-value = .0488). Affected patients presented with other comorbidities: diabetes (≥52), sepsis (≥48), lung diseases (≥39), kidney diseases (≥32) etc. (p-value < .0001). Resistance to fluconazole (44.29%), amphotericin B (15.46%), voriconazole (12.67%), caspofungin (3.48%) etc. were common (p-value = .0059). Commonly used diagnostic tools included PCR (30.38%), Bruker MALDI-TOF MS (14.00%), Vitek 2 YST ID (11.93%), AFLP (11.55%) and WGS (10.04%) (p-value = .002). Multidrug resistance, high attributable mortality and persistence are associated with C. auris infections. Two novel drugs, SCY-078 and VT-1598, are currently in the pipeline. Contact precautions, strict infection control, periodic surveillance and cleaning with chlorine-based detergents, efficient, faster and cheaper detection tools are necessary for prevention, containment and early diagnosis of C. auris infections.
Topics: Antifungal Agents; Candida; Candidemia; Drug Resistance, Multiple, Fungal; Humans; Microbial Sensitivity Tests
PubMed: 29345117
DOI: 10.1002/mbo3.578 -
Frontiers in Cellular and Infection... 2021While most fungi have the ability to reproduce sexually, multiple independent lineages have lost meiosis and developed parasexual cycles in its place. Emergence of... (Review)
Review
While most fungi have the ability to reproduce sexually, multiple independent lineages have lost meiosis and developed parasexual cycles in its place. Emergence of parasexual cycles is particularly prominent in medically relevant fungi from the CUG paraphyletic group of species. Since the discovery of parasex in roughly two decades ago, it has served as the model for species. Importantly, parasex in retains hallmarks of meiosis including genetic recombination and chromosome segregation, making it a potential driver of genetic diversity. Furthermore, key meiotic genes play similar roles in parasex and highlights parallels between these processes. Yet, the evolutionary role of parasex in adaptation and the extent of resulting genotypic and phenotypic diversity remain as key knowledge gaps in this facultative reproductive program. Here, we present our current understanding of parasex, the mechanisms governing its regulation, and its relevance to biology.
Topics: Biological Evolution; Candida; Candida albicans; Genotype; Meiosis
PubMed: 34966696
DOI: 10.3389/fcimb.2021.796929 -
Microbiology Spectrum Aug 2015Intravascular device-related infections are often associated with biofilms (microbial communities encased within a polysaccharide-rich extracellular matrix) formed by... (Review)
Review
Intravascular device-related infections are often associated with biofilms (microbial communities encased within a polysaccharide-rich extracellular matrix) formed by pathogens on the surfaces of these devices. Candida species are the most common fungi isolated from catheter-, denture-, and voice prosthesis-associated infections and also are commonly isolated from contact lens-related infections (e.g., fungal keratitis). These biofilms exhibit decreased susceptibility to most antimicrobial agents, which contributes to the persistence of infection. Recent technological advances have facilitated the development of novel approaches to investigate the formation of biofilms and identify specific markers for biofilms. These studies have provided extensive knowledge of the effect of different variables, including growth time, nutrients, and physiological conditions, on biofilm formation, morphology, and architecture. In this article, we will focus on fungal biofilms (mainly Candida biofilms) and provide an update on the development, architecture, and resistance mechanisms of biofilms.
Topics: Animals; Antifungal Agents; Biofilms; Candida; Candidiasis; Drug Resistance, Fungal; Humans
PubMed: 26350306
DOI: 10.1128/microbiolspec.MB-0020-2015 -
Trends in Microbiology May 2011Most cases of candidosis have been attributed to Candida albicans, but recently non-C. albicans Candida species have been identified as frequent human pathogens. Candida... (Review)
Review
Most cases of candidosis have been attributed to Candida albicans, but recently non-C. albicans Candida species have been identified as frequent human pathogens. Candida pathogenicity has been attributed to several factors, including adhesion to medical devices and/or host cells, biofilm formation, and secretion of hydrolytic enzymes (proteases, phospholipases and haemolysins). Although 'new'Candida species are emerging, there is still a lack of information about their pathogenicity. This review discusses recent advances in our knowledge of Candida glabrata, Candida parapsilosis and Candida tropicalis virulence factors, specifically those of adhesion and biofilm formation, which are key components in Candida pathogenicity.
Topics: Biofilms; Candida; Candidiasis; Cell Adhesion; Humans
PubMed: 21411325
DOI: 10.1016/j.tim.2011.02.003 -
Journal of Applied Microbiology Feb 2017Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to... (Review)
Review
Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various micro-organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm-related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida-formed biofilm.
Topics: Biofilms; Candida; Candida albicans; Candidiasis; DNA; Humans; Hyphae; Quorum Sensing; Respiratory Tract Infections; Virulence Factors
PubMed: 27770500
DOI: 10.1111/jam.13330 -
Frontiers in Cellular and Infection... 2022is an emergent pathogen with a high rate of mortality associated with its biofilm formation. Biofilm formation has important repercussions on the public health system....
is an emergent pathogen with a high rate of mortality associated with its biofilm formation. Biofilm formation has important repercussions on the public health system. However, little is still known about its biofilm life cycle. The present study analyzed the biofilm life cycle of and during various timepoints (24, 48, 72, and 96 h) through biomass assays, colony-forming unit (CFU) counting, and epifluorescence and scanning electron microscopies. Our results showed a significant difference between and biofilms in each biomass and viability assay. All-time samples in the biomass and viability assays confirmed statistical differences between the species through pairwise Wilcoxon tests ( < 0.05). demonstrated a lower biomass growth but reached nearly the same level of biomass at 96 h, while the CFU counting assays exhibited a superior number of viable cells within the biofilm. Statistical differences were also found between and biofilms from 48- and 72-h microscopies, demonstrating with a higher number of total cells within biofilms and cells with a superior cell area and higher matrix production. Therefore, the present study proved the higher biofilm production of .
Topics: Animals; Biofilms; Candida; Candida albicans; Candida tropicalis; Life Cycle Stages
PubMed: 36061861
DOI: 10.3389/fcimb.2022.953168 -
The Brazilian Journal of Infectious... 2019
Topics: Brazil; Candida; Candidiasis; Drug Resistance, Multiple, Fungal; Humans
PubMed: 31152687
DOI: 10.1016/j.bjid.2019.05.004 -
Infection and Immunity Nov 2023The pathogenic yeast represents a global threat of the utmost clinical relevance. This emerging fungal species is remarkable in its resistance to commonly used...
The pathogenic yeast represents a global threat of the utmost clinical relevance. This emerging fungal species is remarkable in its resistance to commonly used antifungal agents and its persistence in the nosocomial settings. The innate immune system is one the first lines of defense preventing the dissemination of pathogens in the host. is susceptible to circulating phagocytes, and understanding the molecular details of these interactions may suggest routes to improved therapies. In this work, we examined the interactions of this yeast with macrophages. We found that macrophages avidly phagocytose ; however, intracellular replication is not inhibited, indicating that resists the killing mechanisms imposed by the phagocyte. Unlike , phagocytosis of does not induce macrophage lysis. The transcriptional response of to macrophage phagocytosis is very similar to other members of the CUG clade (), i.e., downregulation of transcription/translation and upregulation of alternative carbon metabolism pathways, transporters, and induction of oxidative stress response and proteolysis. Gene family expansions are common in this yeast, and we found that many of these genes are induced in response to macrophage co-incubation. Among these, amino acid and oligopeptide transporters, as well as lipases and proteases, are upregulated. Thus, shares key transcriptional signatures shared with other fungal pathogens and capitalizes on the expansion of gene families coding for potential virulence attributes that allow its survival, persistence, and evasion of the innate immune system.
Topics: Candida; Candida auris; Candida albicans; Antifungal Agents; Macrophages; Candida parapsilosis
PubMed: 37815367
DOI: 10.1128/iai.00274-23