Sentinel surveillance of invasive candidiasis in Spain: epidemiology and antifungal susceptibility

Trends in antifungal resistance in Candida from a multicenter study conducted in Madrid (CANDIMAD study): fluconazole-resistant C. parapsilosis spreading has gained traction in 2022

We previously conducted a multicenter surveillance study on Candida epidemiology and antifungal resistance in Madrid (CANDIMAD study; 2019-2021), detecting an increase in fluconazole-resistant Candida parapsilosis. We here present data on isolates collected in 2022. Furthermore, we report the epidemiology and antifungal resistance trends during the entire period, including an analysis per ward of admission. Candida spp. incident isolates from blood cultures and intra-abdominal samples from patients cared for at 16 hospitals in Madrid, Spain, were tested with the EUCAST E.Def 7.3.2 method against amphotericin B, azoles, micafungin, anidulafungin, and ibrexafungerp and were molecularly characterized. In 2022, we collected 766 Candida sp. isolates (686 patients; blood cultures, 48.8%). Candida albicans was the most common species found, and Candida auris was undetected. No resistance to amphotericin B was found. Overall, resistance to echinocandins was low (0.7%), whereas fluconazole resistance was 12.0%, being higher in blood cultures (16.0%) mainly due to fluconazole-resistant C. parapsilosis clones harboring the Y132F-R398I ERG11p substitutions. Ibrexafungerp showed in vitro activity against the isolates tested. Whereas C. albicans was the dominant species in most hospital wards, we observed increasing C. parapsilosis proportions in blood. During the entire period, echinocandin resistance rates remained steadily low, while fluconazole resistance increased in blood from 6.8% (2019) to 16% (2022), mainly due to fluconazole-resistant C. parapsilosis (2.6% in 2019 to 36.6% in 2022). Up to 7 out of 16 hospitals were affected by fluconazole-resistant C. parapsilosis. In conclusion, rampant clonal spreading of C. parapsilosis fluconazole-resistant genotypes is taking place in Madrid.

Species Distribution and Antifungal Susceptibilities of Candida Species Isolated From Blood Culture

Introduction Candida species (spp.) are among the leading agents of bloodstream infections. Candidemias are a major cause of morbidity and mortality. Having an understanding of Candida epidemiology and antifungal susceptibility patterns in each center is crucial in guiding the management of candidemia. In this study, the species distribution and antifungal susceptibility of Candida spp. isolated from blood culture at the University of Health Sciences, Bursa Yuksek Ihtisas Training & Research Hospital were examined and the first data on the epidemiology of candidemia in our center were presented. Methods A total of 236 Candida strains isolated from blood cultures in our hospital over a four-year period were analyzed and their antifungal susceptibilities were studied retrospectively. Strains were identified at the species complex (SC) level by the germ tube test, morphology in cornmeal-tween 80 medium, and the automated VITEK 2 Compact (bioMérieux, Marcy-l'Étoile, France) system. Antifungal susceptibility tests were performed on VITEK 2 Compact (bioMérieux, Marcy-l'Étoile, France) system. The susceptibilities of the strains to fluconazole, voriconazole, micafungin, and amphotericin B were determined according to Clinical and Laboratory Standards Institute (CLSI) guidelines and epidemiologic cut-off values. Results Of the Candida (C.) strains, 131 were C. albicans (55.5%), 40 were C. parapsilosis SC (16.9%), 21 were C. tropicalis (8.9%), 19 were C. glabrata SC (8.1%), eight were C. lusitaniae (3.4%), seven were C. kefyr (3.0%), six were C. krusei (2.6%), two were C. guilliermondii (0.8%) and two were C. dubliniensis (0.8%). Amphotericin B resistance was not detected in Candida strains. Micafungin susceptibility was 98.3%, and four C. parapsilosis SC strains (10%) were intermediate (I) to micafungin. Fluconazole susceptibility was 87.2%. Apart from C. krusei strains which intrinsically resistant to fluconazole, three C. parapsilosis (7.5%), one C. glabrata SC (5.3%) strain were resistant (R) to fluconazole, and one C. lusitaniae (12.5%) strain was wild-type (WT). Voriconazole susceptibility of Candida strains was 98.6%. Two C. parapsilosis SC strains were I to voriconazole, while one strain was R. Conclusion In this study, the first epidemiological data of candidemia agents in our hospital were presented. It was determined that rare and naturally resistant species did not cause any problem in our center yet. C. parapsilosis SC strains showed decreased susceptibility to fluconazole, whereas Candida strains were highly susceptible to the four antifungals tested. Close monitoring of these data will help guide the treatment of candidemia.

Blood and intra-abdominal Candida spp. from a multicentre study conducted in Madrid using EUCAST: emergence of fluconazole resistance in Candida parapsilosis, low echinocandin resistance and absence of Candida auris

OBJECTIVES

We prospectively monitored the epidemiology and antifungal susceptibility of Candida spp. from blood cultures and intra-abdominal samples in patients admitted to hospitals in the Madrid area.

METHODS

Between 2019 and 2021, we prospectively collected incident isolates [one per species, patient and compartment (blood cultures versus intra-abdominal samples)] from patients admitted to any of 16 hospitals located in Madrid. We studied the antifungal susceptibilities to amphotericin B, triazoles, micafungin, anidulafungin and ibrexafungerp following the EUCAST E.Def 7.3.2 procedure.

RESULTS

A total of 2107 Candida spp. isolates (1895 patients) from blood cultures (51.7%) and intra-abdominal samples were collected. Candida albicans, the Candida glabrata complex, the Candida parapsilosis complex, Candida tropicalis and Candida krusei accounted for 96.9% of the isolates; in contrast, Candida auris was undetected. Fluconazole resistance in Candida spp. was higher in blood cultures than in intra-abdominal samples (9.1% versus 8.2%; P > 0.05), especially for the C. parapsilosis complex (16.6% versus 3.6%, P < 0.05), whereas echinocandin resistance tended to be lower in blood cultures (0.5% versus 1.0%; P > 0.05). Resistance rates have risen, particularly for fluconazole in blood culture isolates, which increased sharply in 2021. Ibrexafungerp showed in vitro activity against most isolates. Species distributions and resistance rates varied among hospitals.

CONCLUSIONS

Whereas no C. auris isolates were detected, fluconazole-resistant C. parapsilosis isolates have been spreading across the region and this has pulled up the rate of fluconazole resistance. In contrast, the rate of echinocandin resistance continues to be low.

Regulatory network controls microbial biofilm development, with Candida albicans as a representative: from adhesion to dispersal

Microorganisms mainly exist in the form of biofilm in nature. Biofilm can contaminate food and drinking water system, as well as cause chronic wound infections, thereby posing a potential threat to public health safety. In the last two decades, researchers have made efforts to investigate the genetic contributors control different stages of biofilm development (adherence, initiation, maturation, and dispersal). As an opportunistic pathogen, C. albicans causes severe superficial or systemic infections with high morbidity and mortality under conditions of immune dysfunction. It has been reported that 80% of C. albicans infections are directly or indirectly associated with biofilm formation on host or abiotic surfaces including indwelling medical devices, resulting in high morbidity and mortality. Significantly, the outcome of C. albicans biofilm development includes enhanced invasion, exacerbated inflammatory responses and intrinsic resistance to antimicrobial chemotherapy. Thus, this review aimed at providing a comprehensive overview of the regulatory network controls microbial biofilm development, with C. albicans as a representative, served as reference for therapeutic targets.

The Role of HMGB1 in Invasive Candida albicans Infection

INTRODUCTION

High mobility group box 1 (HMGB1) is an important "late" inflammatory mediator in bacterial sepsis. Ethyl pyruvate (EP), an inhibitor of HMGB1, can prevent bacterial sepsis by decreasing HMGB1 levels. However, the role of HMGB1 in fungal sepsis is still unclear. Therefore, we investigated the role of HMGB1 and EP in invasive C. albicans infection.

METHODS

We measured serum HMGB1 levels in patients with sepsis with C. albicans infection and without fungal infection, and control subjects. We collected clinical indices to estimate correlations between HMGB1 levels and disease severity. Furthermore, we experimentally stimulated mice with C. albicans and C. albicans + EP. Then, we examined HMGB1 levels from serum and tissue, investigated serum levels of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), determined pathological changes in tissues, and assessed mortality.

RESULTS

Serum HMGB1 levels in patients with severe sepsis with C. albicans infection were elevated. Increased HMGB1 levels were correlated with procalcitonin (PCT), C-reactive protein (CRP), 1,3-β-D-Glucan (BDG) and C. albicans sepsis severity. HMGB1 levels in serum and tissues were significantly increased within 7 days after mice were infected with C. albicans. The administration of EP inhibited HMGB1 levels, decreased tissue damage, increased survival rates and inhibited the release of TNF-α and IL-6.

CONCLUSIONS

HMGB1 levels were significantly increased in invasive C. albicans infections. EP prevented C. albicans lethality by decreasing HMGB1 expression and release. HMGB1 may provide an effective diagnostic and therapeutic target for invasive C. albicans infections.

Candida Bloodstream Infections: Changes in Epidemiology and Increase in Drug Resistance

The literature on bloodstream infections (BSIs) have predominantly been biased towards bacteria, given their superior clinical significance in comparison with the other types of microorganisms. Fungal pathogens have epidemiologically received relatively less attention, although they constitute an important proportion of BSI aetiologies. In this review, the authors discuss the clinical relevance of fungal BSIs in the context of Candida species, as well as treatment options for the infections, emphasizing the compelling need to develop newer antifungals and strengthen antimicrobial stewardship programmes in the wake of the rapid spread of antifungal resistance.

Deciphering the epidemiology of invasive candidiasis in the intensive care unit: is it possible?

Invasive candidiasis (IC) has emerged in the last decades as an important cause of morbidity, mortality, and economic load in the intensive care unit (ICU). The epidemiology of IC is still a difficult and unsolved enigma for the literature. Accurate estimation of the true burden of IC is difficult due to variation in definitions and limitations inherent to available case-finding methodologies. Candidemia and intra-abdominal candidiasis (IAC) are the two predominant types of IC in ICU. During the last two decades, an increase in the incidence of candidemia has been constantly reported particularly in the expanding populations of elderly or immunosuppressed patents, with a parallel change in Candida species (spp.) distribution worldwide. Epidemiological shift in non-albicans spp. has reached worrisome trends. Recently, a novel, multidrug-resistant Candida spp., Candida auris, has globally emerged as a nosocomial pathogen causing a broad range of healthcare-associated invasive infections. Epidemiological profile of IAC remains imprecise. Though antifungal drugs are available for Candida infections, mortality rates continue to be high, estimated to be up to 50%. Increased use of fluconazole and echinocandins has been associated with the emergence of resistance to these drugs, which affects particularly C. albicans and C. glabrata. Crucial priorities for clinicians are to recognize the epidemiological trends of IC as well as the emergence of resistance to antifungal agents to improve diagnostic techniques and strategies, develop international surveillance networks and antifungal stewardship programmes for a better epidemiological control of IC.

Monitoring the Epidemiology and Antifungal Resistance of Yeasts Causing Fungemia in a Tertiary Care Hospital in Madrid, Spain: Any Relevant Changes in the Last 13 Years?

We conducted an updated analysis on yeast isolates causing fungemia in patients admitted to a tertiary hospital in Madrid, Spain, over a 13-year period. We studied 896 isolates associated with 872 episodes of fungemia in 857 hospitalized patients between January 2007 and December 2019. Antifungal susceptibility was assessed by EUCAST EDef 7.3.2. Mutations conferring azole and echinocandin resistance were further studied, and genotyping of resistant clones was performed with species-specific microsatellite markers. Candida albicans (45.8%) was the most frequently identified species, followed by the Candida parapsilosis complex (26.4%), Candida glabrata (12.3%), Candida tropicalis (7.3%), Candida krusei (2.3%), other Candida spp. (3.1%), and non-Candida yeasts (2.8%). The rate of fluconazole resistance in Candida spp. was 4.7%, ranging from 0% (C. parapsilosis) to 9.1% (C. glabrata). The overall rate of echinocandin resistance was 3.1%. Resistance was highly influenced by the presence of intrinsically resistant species. Although the number of isolates between 2007 and 2013 was almost 2-fold higher than that in the period from 2014 to 2019 (566 versus 330), fluconazole resistance in Candida spp. was greater in the second period (3.5% versus 6.8%; P < 0.05), while overall resistance to echinocandins remained stable (3.5% versus 2.4%; P > 0.05). Resistant clones were collected from different wards and/or time points, suggesting that there were no epidemiological links. The number of fungemia episodes has been decreasing over the last 13 years, with a slight increase in the rate of fluconazole resistance and stable echinocandin resistance. Antifungal resistance is not the cause of the spread of resistant clones.

Surveillance study of the prevalence, species distribution, antifungal susceptibility, risk factors and mortality of invasive candidiasis in a tertiary teaching hospital in Southwest China

BACKGROUND

Invasive candidiasis (IC) is the most common invasive fungal infection. The epidemiology of IC in hospitalized patients has been widely investigated in many metropolitan cities; however, little information from medium and small cities is known.

METHODS

A 5-year retrospective study was carried out to analyze the prevalence, species distribution, antifungal susceptibility, risk factors and mortality of inpatients with invasive Candida infection in a regional tertiary teaching hospital in Southwest China.

RESULTS

A total of 243 inpatients with invasive Candida infection during the five-year study period were identified, with a mean annual incidence of 0.41 cases per 1000 admissions and a 30-day mortality rate of 12.3%. The species distributions of Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, Candida parapsilosis and other Candida species was 45.3, 30.0, 15.2, 4.9, 2.1 and 2.5%, respectively. The total resistance rates of fluconazole (FCA), itraconazole (ITR) and voriconazole (VRC) were 18.6, 23.1 and 18.5%, respectively. Respiratory dysfunction, pulmonary infection, cardiovascular disease, chronic/acute renal failure, mechanical ventilation, abdominal surgery, intensive care in adults, septic shock and IC due to C. albicans were associated with 30-day mortality (P < 0.05) according to the univariate analyses. Respiratory dysfunction [odds ratio (OR), 9.80; 95% confidence interval (CI), 3.24-29.63; P < 0.001] and IC due to C. albicans (OR, 3.35; 95% CI, 1.13-9.92; P = 0.029) were the independent predictors of 30-day mortality.

CONCLUSIONS

This report shows that the incidence and mortality rates are lower and that the resistance rates to azoles are higher in medium and small cities than in large cities and that the species distributions and risk factors in medium and small cities are different from those in large cities in China. It is necessary to conduct epidemiological surveillance in medium and small cities to provide reference data for the surveillance of inpatients with IC infections.

Enrichment of ATP Binding Proteins Unveils Proteomic Alterations in Human Macrophage Cell Death, Inflammatory Response, and Protein Synthesis after Interaction with Candida albicans

Macrophages are involved in the primary human response to Candida albicans. After pathogen recognition, signaling pathways are activated, leading to the production of cytokines, chemokines, and antimicrobial peptides. ATP binding proteins are crucial for this regulation. Here, a quantitative proteomic and phosphoproteomic approach was carried out for the study of human macrophage ATP-binding proteins after interaction with C. albicans. From a total of 547 nonredundant quantified proteins, 137 were ATP binding proteins and 59 were detected as differentially abundant. From the differentially abundant ATP-binding proteins, 6 were kinases (MAP2K2, SYK, STK3, MAP3K2, NDKA, and SRPK1), most of them involved in signaling pathways. Furthermore, 85 phosphopeptides were quantified. Macrophage proteomic alterations including an increase of protein synthesis with a consistent decrease in proteolysis were observed. Besides, macrophages showed changes in proteins of endosomal trafficking together with mitochondrial proteins, including some involved in the response to oxidative stress. Regarding cell death mechanisms, an increase of antiapoptotic over pro-apoptotic signals is suggested. Furthermore, a high pro-inflammatory response was detected, together with no upregulation of key mi-RNAs involved in the negative feedback of this response. These findings illustrate a strategy to deepen the knowledge of the complex interactions between the host and the clinically important pathogen C. albicans.

Virulence factors of Candida spp. obtained from blood cultures of patients with candidemia attended at tertiary hospitals in Northeast Brazil

BACKGROUND

Yeasts of the Candida genus are one of the most common causes of bloodstream infections associated with high rates of morbidity and mortality, mainly affecting immunocompromised patients. We aimed to identify yeasts obtained from blood cultures of patients interned at tertiary hospitals in Brazil.

METHODS

We evaluated some of the major virulence factors of Candida spp., including the ability to adhere to human buccal epithelial cells, biofilm formation, hemolytic and phospholipase activity.

RESULTS

We analyzed 70 isolates of Candida spp. obtained from March 2011 and March 2015. Candida spp. showed different peculiarities in terms of expression of virulence factors evaluated in vitro. C. albicans strains were more adherent to HBEC than all the other Candida species. C. tropicalis strains were considered strong biofilm producers. Strains belonging to the C. parapsilosis species complex were able to produce hemolysins, while C. glabrata was also able to lyse erythrocytes and to produce phospholipase.

CONCLUSION

These results suggest that Non-Candida albicans Candida species are also able to express virulence factors which play an important role in bloodstream infectious caused by these yeasts.

Epidemiology of antifungal susceptibility: Review of literature

Fungal infections are a major cause of morbidity and mortality despite the latest developments of diagnostic tools and therapeutic options. Early initiation of the appropriate antifungal therapy has been demonstrated to have a direct impact on the patient's outcome. Antifungal susceptibility testing methods are available to detect antifungal resistance and to determine the best treatment for a specific fungus. American and European standards have been developed, as well as equivalent commercial systems, which are more appropriate for clinical laboratories. These studies have allowed the development of interpretative breakpoints against the most frequent agents of fungal infections in the world. Surveillance of antifungal susceptibility patterns can provide the local drug resistance data to the clinicians, which can further aid better management of patients. Antifungal susceptibility tests have become essential tools to identify resistance to antifungals, to know the local and global disease epidemiology and to guide the treatment of fungal diseases. The distribution of species and the prevalence of antifungal resistance in fungi isolates varied among different areas. Here we summarize the epidemiology of antifungal susceptibility pattern of different fungal species.

Microbiologic and clinical characteristics of biofilm-forming Candida parapsilosis isolates associated with fungaemia and their impact on mortality

OBJECTIVES

Biofilm formation (BF) by fungal isolates may dramatically complicate infection. We determined the ability of Candida parapsilosis isolates from single fungaemia episodes to form biofilms and we analysed biofilm subgroups for antifungal susceptibility and pathogenic potential. We then correlated BF with clinical characteristics and outcomes of the episodes.

METHODS

BF was measured using the crystal violet biomass assay. Antifungal susceptibility of preformed biofilms was assessed, and virulence was studied using the Galleria mellonella model. A retrospective analysis of patients' clinical records was performed.

RESULTS

Of 190 patient-unique isolates, 84, 38 and 68 were identified as having high BF (HBF), moderate BF (MBF) or low BF (LBF), respectively. Among 30 randomly selected isolates, nine (eight HBF and one MBF), six (all HBF) and one (HBF) isolates had elevated sessile minimum inhibitory concentrations to fluconazole, anidulafungin or amphotericin B; all HBF and MBF isolates had elevated voriconazole sessile minimum inhibitory concentrations. G. mellonella killing rates of HBF isolates were significantly greater than MBF (or LBF) isolates (50% vs. 20%, 2 days from infection). By comparing HBF/MBF (106 patients) and LBF (84 patients) groups, we found that HBF/MBF patients had more central venous catheter-related fungaemias (62/106 (58.5%) vs. 29/84 (34.5%), p 0.001) and were more likely to die at 30 days from fungaemia onset (61/106 (57.5%) vs. 28/84 (33.3%), p 0.01). In the HBF/MBF group, azole antifungal therapy and central venous catheter removal were significantly associated with a higher and lower 30-day mortality rate, respectively.

CONCLUSIONS

C. parapsilosis BF influences the clinical outcome in patients with fungaemia.

EPICO 4.0. 'Total quality' in the management of invasive candidiasis in critically ill patients by analysing the integrated process

BACKGROUND

A high quality integrated process in the clinical setting of non-neutropenic critically ill patients at risk for invasive candidiasis is a necessary tool to improve the management of these patients.

AIMS

To identify the key points on invasive candidiasis in order to develop a set of recommendations with a high level of consensus required for the creation of a total quality integrated process for the management of non-neutropenic critically ill patients at risk of invasive candidiasis.

METHODS

After a thorough review of the literature of the previous five years, a Spanish prospective questionnaire, which measured consensus by the Delphi technique, was anonymously conducted by e-mail, including 31 national multidisciplinary experts with extensive experience in invasive fungal infections, from six national scientific societies. The experts included a specialist in intensive care medicine, anesthetists, microbiologists, pharmacologists, and specialists in infectious diseases that responded 27 questions prepared by the coordination group. The educational objectives considered six processes that included knowledge of the local epidemiology, the creation and development of multidisciplinary teams, the definitions of the process, protocols, and indicators (KPI), an educational phase, hospital implementation, and the measurement of outcomes. The level of agreement among experts in each category to be selected should exceed 70%. In a second phase, after drawing up the recommendations of the selected processes, a face to face meeting with more than 60 specialists was held. The specialists were asked to validate the pre-selected recommendations.

MEASURES AND MAIN OUTCOMES

Firstly, 20 recommendations from all the sections were pre-selected: Knowledge of local epidemiology (3 recommendations), creation and development of multidisciplinary teams (3), definition of the process, protocols and indicators (1), educational phase (3), hospital implementation (3), and measurement of outcomes (7). After the second phase, 18 recommendations were validated, and it was concluded that the minimum team or core necessary for the development of an efficient program in the use of antifungal drugs in non-neutropenic critically ill patients must consist of a specialist in infectious diseases, a clinical pharmacist, a microbiologist, a specialist in intensive care medicine, a specialist in anesthesia and recovery, and an administrator or member of the medical management team, and, in order to be cost-effective, it should be implemented in hospitals with over 200 beds. In addition, it is recommended to apply a consensual check list for the evaluation of the diagnostic process and treatment of invasive candidiasis in patients that have started an antifungal treatment. The management of external knowledge and individual learning stand out as active educational strategies. The main strategies for measuring patient safety outcomes are the analysis of the results achieved, and learning activities; assess, review and refine the deployment of the processes; quality control; epidemiological surveillance and applied research; benchmarking; and basic research. The results of the integrated process should be annually disseminated outside the hospital.

CONCLUSIONS

Optimizing the management of invasive candidiasis requires the application of the knowledge and skills detailed in our recommendations. These recommendations, based on the Delphi methodology, facilitate the creation of a total quality integrated process in critically-ill patients at risk for invasive candidiasis.

ICU-acquired candidaemia in France: Epidemiology and temporal trends, 2004-2013 - A study from the REA-RAISIN network

OBJECTIVE

Candidaemia is a life-threatening infectious disease, associated with septic shock, multiple organ failure, and a high mortality rate. In France, reported data on the incidence of ICU-acquired candidaemia and the causative Candida species are scarce. The objective of this study was to determine temporal trends in epidemiology and risk factors of intensive care unit-acquired candidaemia (ICU-Cand) and ICU mortality among a very large population of ICU patients.

METHOD

Demographics, patient risk factors, invasive device exposure and nosocomial infection in ICU patient were collected from 2004 to 2013 in a national network of 213 ICUs: REA-RAISIN. Incidence and risk factors for candidaemia and ICU mortality were assessed.

RESULTS

Out of 246,459 ICU patients, 851 developed an ICU-cand, representing 0.3 per 1000 patients-days. The incidence rose sharply over time. Candida albicans was the main species. The overall and ICU mortality was 52.4% in ICU-cand patients. The main risk factors of ICU-cand were length of stay, severity of illness and antimicrobial therapy at ICU admission, immune status and use of invasive procedure. ICU-cand was an independent risk factor of mortality (OR: 1.53; 95%CI [1.40-1.70]); in a sub-group analysis, independent effects on mortality were observed with C. albicans (OR: 1.45 [1.23-1.71]), Candida tropicalis (OR: 2.11 [1.31-3.39]) and "other" Candida species (OR: 1.64 [1.09-2.45]).

CONCLUSION

ICU candidaemia ranked sixth among bloodstream infections, and its average annual incidence was 0.3 per 1000 patients days. Despite of new therapy and international recommendation, the incidence rose sharply during the study period, and ICU mortality remained high.

Scientific Opinion on the update of the list of QPS-recommended biological agents intentionally added to food or feed as notified to EFSA

EFSA is requested to assess the safety of a broad range of biological agents in the context of notification for market authorisation as sources of food and feed additives, food enzymes and plant protection products. The qualified presumption of safety (QPS) assessment was developed to provide a harmonised generic pre-assessment to support safety risk assessments performed by EFSA's scientific Panels. The safety of unambiguously defined biological agents (at the highest taxonomic unit appropriate for the purpose for which an application is intended), and the completeness of the body of knowledge are assessed. Identified safety concerns for a taxonomic unit are, where possible and reasonable in number, reflected as 'qualifications' in connection with a recommendation for a QPS status. The list of QPS recommended biological agents was reviewed and updated in the current opinion and therefore becomes the valid list. The 2016 update reviews previously assessed microorganisms including bacteria, yeasts and viruses used for plant protection purposes following an Extensive Literature Search strategy. The taxonomic units related to the new notifications received since the 2013 QPS opinion, were periodically evaluated for a QPS status and the results published as Statements of the BIOHAZ Panel. Carnobacterium divergens, Lactobacillus diolivorans, Microbacterium imperiale, Pasteuria nishizawae, Pediococcus parvulus, Bacillus flexus, Bacillus smithii, Xanthomonas campestris and Candida cylindracea were recommended for the QPS list. All taxonomic units previously recommended for the 2013 QPS list had their status reconfirmed as well their qualifications with the exception of Pasteuria nishizawae for which the qualification was removed. The exclusion of filamentous fungi and enterococci from the QPS evaluations was reconsidered but monitoring will be maintained and the status will be re-evaluated in the next QPS Opinion update. Evaluation of bacteriophages should remain as a case-by-case procedure and should not be considered for QPS status.

Candida glabrata Biofilms: How Far Have We Come?

Infections caused by Candida species have been increasing in the last decades and can result in local or systemic infections, with high morbidity and mortality. After Candida albicans, Candida glabrata is one of the most prevalent pathogenic fungi in humans. In addition to the high antifungal drugs resistance and inability to form hyphae or secret hydrolases, C. glabrata retain many virulence factors that contribute to its extreme aggressiveness and result in a low therapeutic response and serious recurrent candidiasis, particularly biofilm formation ability. For their extraordinary organization, especially regarding the complex structure of the matrix, biofilms are very resistant to antifungal treatments. Thus, new approaches to the treatment of C. glabrata's biofilms are emerging. In this article, the knowledge available on C. glabrata's resistance will be highlighted, with a special focus on biofilms, as well as new therapeutic alternatives to control them.

Factors related to outcome of bloodstream infections due to Candida parapsilosis complex

Background

Although Candida albicans is the most common cause of fungal blood stream infections (BSIs), infections due to Candida species other than C. albicans are rising. Candida parapsilosis complex has emerged as an important fungal pathogen and became one of the main causes of fungemia in specific geographical areas. We analyzed the factors related to outcome of candidemia due to C. parapsilosis in a single tertiary referral hospital over a five-year period.

Methods

A retrospective observational study of all cases of candidemia was carried out at a 980-bedded University Hospital in Italy. Data regarding demographic characteristics and clinical risk factors were collected from the patient’s medical records. Antifungal susceptibility testing was performed and MIC results were interpreted according to CLSI species-specific clinical breakpoints.

Results

Of 270 patients diagnosed with Candida BSIs during the study period, 63 (23 %) were infected with isolates of C. parapsilosis complex which represented the second most frequently isolated yeast after C. albicans. The overall incidence rate was 0.4 episodes/1000 hospital admissions. All the strains were in vitro susceptible to all antifungal agents. The overall crude mortality at 30 days was 27 % (17/63), which was significantly lower than that reported for C. albicans BSIs (42 % [61/146], p = 0.042). Being hospitalized in ICU resulted independently associated with a significant higher risk of mortality (HR 4.625 [CI95% 1.015–21.080], p = 0.048). Conversely, early CVC removal was confirmed to be significantly associated with a lower risk of mortality (HR 0.299 [CI95% 0.102–0.874], p = 0.027). Finally, the type of primary antifungal therapy did not influence the outcome of infection.

Conclusions

Candidemia due to C. parapsilosis complex, the second most commonly causative agent of yeast BSIs in our center, is characterized by a non-negligible mortality at 30 days. An early CVC removal is associated with a significant reduced mortality.

Resistance Surveillance in Candida albicans: A Five-Year Antifungal Susceptibility Evaluation in a Brazilian University Hospital

Candida albicans caused 44% of the overall candidemia episodes from 2006 to 2010 in our university tertiary care hospital. As different antifungal agents are used in therapy and also immunocompromised patients receive fluconazole prophylaxis in our institution, this study aimed to perform an antifungal susceptibility surveillance with the C.albicans bloodstream isolates and to characterize the fluconazole resistance in 2 non-blood C.albicans isolates by sequencing ERG11 gene. The study included 147 C. albicans bloodstream samples and 2 fluconazole resistant isolates: one from oral cavity (LIF 12560 fluconazole MIC: 8μg/mL) and one from esophageal cavity (LIF-E10 fluconazole MIC: 64μg/mL) of two different patients previously treated with oral fluconazole. The in vitro antifungal susceptibility to amphotericin B (AMB), 5-flucytosine (5FC), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), caspofungin (CASP) was performed by broth microdilution methodology recommended by the Clinical and Laboratory Standards Institute documents (M27-A3 and M27-S4, CLSI). All blood isolates were classified as susceptible according to CLSI guidelines for all evaluated antifungal agents (MIC range: 0,125–1.00 μg/mL for AMB, ≤0.125–1.00 μg/mL for 5FC, ≤0.125–0.5 μg/mL for FLC, ≤0.015–0.125 μg/mL for ITC, ≤0.015–0.06 μg/mL for VRC and ≤0.015–0.125 μg/mL for CASP). In this study, we also amplified and sequenced the ERG11 gene of LIF 12560 and LIF-E10 C.albicans isolates. Six mutations encoding distinct amino acid substitutions were found (E116D, T128K, E266D, A298V, G448V and G464S) and these mutations were previously described as associated with fluconazole resistance. Despite the large consumption of antifungals in our institution, resistant blood isolates were not found over the trial period. Further studies should be conducted, but it may be that the very prolonged direct contact with the oral antifungal agent administered to the patient from which was isolated LIF E-10, may have contributed to the development of resistance.

Nosocomial candidemia in patients admitted to medicine wards compared to other wards: a multicentre study

PURPOSE

Risk factors for nosocomial candidemia, severity of sepsis, treatment, and outcome were compared between patients admitted to medicine wards and those to surgical and intensive care units (ICUs).

METHODS

Data were retrospectively collected from patients belonging to six referral hospitals in Italy between January 2011 and December 2013. Risk factors for 30-day mortality were evaluated in the whole patient population.

RESULTS

A total of 686 patients (mean age 70 ± 15 years) with candidemia were included. 367 (53.5 %) patients were in medicine wards, and 319 in surgery and ICUs. Host-related risk factors for candidemia were more common in medicine patients whereas healthcare-related factors in surgery/ICU patients. These patients showed severe sepsis and septic shock more commonly (71.7 %) than medicine patients (59.9 %) (p 0.003). The latter underwent central venous catheter (CVC) removal and adequate antifungal therapy less frequently than surgery/ICU patients. 149 (40.6 %) patients died with candidemia in medicine wards and 69 (21.6 %) in other wards (p < 0.001). Overall, the 30-day mortality was 36.3 %. At multivariate analysis, independent risk factors for death were aging, higher Charlson score, severe sepsis and septic shock, and no antifungal therapy, while major surgery and CVC removal were associated with higher probability of survival.

CONCLUSIONS

The burden of risk factors for candidemia was different between medicine patients and those in other wards. Despite the lower severity of candidemia in medicine patients, their mortality turned out to be higher than in surgery or ICU patients. Awareness of the best management of candidemia should be pursued, especially in medicine wards.

Apoptosis of Candida albicans during the Interaction with Murine Macrophages: Proteomics and Cell-Death Marker Monitoring

Macrophages may induce fungal apoptosis to fight against C. albicans, as previously hypothesized by our group. To confirm this hypothesis, we analyzed proteins from C. albicans cells after 3 h of interaction with macrophages using two quantitative proteomic approaches. A total of 51 and 97 proteins were identified as differentially expressed by DIGE and iTRAQ, respectively. The proteins identified and quantified were different, with only seven in common, but classified in the same functional categories. The analyses of their functions indicated that an increase in the metabolism of amino acids and purine nucleotides were taking place, while the glycolysis and translation levels dropped after 3 h of interaction. Also, the response to oxidative stress and protein translation were reduced. In addition, seven substrates of metacaspase (Mca1) were identified (Cdc48, Fba1, Gpm1, Pmm1, Rct1, Ssb1, and Tal1) as decreased in abundance, plus 12 proteins previously described as related to apoptosis. Besides, the monitoring of apoptotic markers along 24 h of interaction (caspase-like activity, TUNEL assay, and the measurement of ROS and cell examination by transmission electron microscopy) revealed that apoptotic processes took place for 30% of the fungal cells, thus supporting the proteomic results and the hypothesis of macrophages killing C. albicans by apoptosis.

Candida albicans cell shaving uncovers new proteins involved in cell wall integrity, yeast to hypha transition, stress response and host-pathogen interaction

The ability to switch from yeast to hyphal growth is essential for virulence in Candida albicans. The cell surface is the initial point of contact between the fungus and the host. In this work, a free-gel proteomic strategy based on tryptic digestion of live yeast and hyphae cells and protein identification using LC-MS/MS methodology was used to identify cell surface proteins. Using this strategy, a total of 943 proteins were identified, of which 438 were in yeast and 928 were in hyphae. Of these proteins, 79 were closely related to the organization and biogenesis of the cell wall, including 28 GPI-anchored proteins, such as Hyr1 and Sod5 which were detected exclusively in hyphae, and Als2 and Sap10which were detected only in yeast. A group of 17 proteins of unknown function were subsequently studied by analysis of the corresponding deletion mutants. We found that four new proteins, Pst3, Tos1, Orf19.3060 and Orf19.5352 are involved in cell wall integrity and in C. albicans' engulfment by macrophages. Moreover, the putative NADH-ubiquinone-related proteins, Ali1, Mci4, Orf19.287 and Orf19.7590, are also involved in osmotic and oxidative resistance, yeast to hypha transition and the ability to damage and invade oral epithelial cells. This article is part of a Special Issue entitled: HUPO 2014.