Impact of prior inappropriate fluconazole dosing on isolation of fluconazole-nonsusceptible Candida species in hospitalized patients with candidemia

Therapeutic drug monitoring of azole antifungal agents

Deep-seated mycoses are generally opportunistic infections that are difficult to diagnose and treat. They are expected to increase with the spread of advanced medical care and aging populations, thus highlighting the need for safe, effective, and rapid drug-based treatments. Depending on a patient's age, sex, underlying diseases, and immune system status, therapeutic drug monitoring (TDM) may be important for assessing variable pharmacokinetic parameters, as well as preventing drug-drug interactions, adverse events, and breakthrough infections caused by fungal resistance. Azole antifungal agents play an important role in the prevention and treatment of deep-seated fungal infections, with each azoles having its own unique pharmacokinetic properties and specific adverse events. Therefore, it is necessary to use national and international guidelines to build evidence for the expansion of TDM indications. This review focuses on the clinical utility and future perspectives of TDM using azole antifungal agents, in the context of recent evidence in the literature.

The Increasing Trend of Triazole-Resistant Candida from Vulvovaginal Candidiasis

Purpose

Candida vaginitis is widely prevalent worldwide and is one of the common gynecological disorders. The aim of this study is to analyze the sensitivity of recurrent vulvovaginal (RVVC) candidiasis to antifungal drugs and its relationship with vaginal microbiota.

Patients and Methods

We Isolated and cultured Candida from RVVC patients, mass spectrometry and broth microdilution method were used to identify and determine MIC values of antifungal drugs. Clinical medical records and vaginal microbiota of RVVC patients were also collected.

Results

The main pathogens causing RVVC are predominantly Candida albicans (70.26%), but in recent years, there has been an increasing proportion of Candida glabrata(24.46%). However, only 15.70% of Candida albicans were sensitive to Voriconazole, 35.84% to Fluconazole and 25.60% to Itraconazole. No fluconazole-resistant Candida glabrata was found. Most Candida krusei strains were sensitive to voriconazole (81.80%). More important MIC values of triazoles were increased in Candida species, when exposed to clotrimazole. In addition, we found that the vaginal microecology of candida vaginitis and bacterial vaginitis was significantly different.

Conclusion

Triazoles resistant Candida species have emerged, leading to the failure of empirical anti-infective therapy. At the same time, the vaginal microecology of candida vaginitis and bacterial vaginitis was significantly different. In addition, a new breakpoint for Candida from RVVC needs to be established.

Tracking Candidemia Trends and Antifungal Resistance Patterns across Europe: An In-Depth Analysis of Surveillance Systems and Surveillance Studies

BACKGROUND

The WHO fungal priority list classifies Candida species as critical and high-priority pathogens, and the WHO GLASS fungi initiative seeks to establish a standardised global framework for antifungal resistance monitoring. We aimed to review resistance rates and antifungal resistance patterns across European surveillance systems and studies in response to these recent calls for action.

METHODS

A systematic review of national and international surveillance systems and peer-reviewed surveillance studies available up to June 2024 was conducted. Descriptive and trend analyses were performed on surveillance data reporting resistance to different antifungals in Candida spp.

RESULTS

In total, 6 national surveillance systems and 28 studies from 13 countries provided candidemia resistance data, mostly about the C. albicans, C. glabrata and C. parapsilosis complex. Azole resistance was most frequently reported (6/6 surveillance systems and 27/28 studies) with the highest resistance rate, especially for C. glabrata, in Croatia (100%, 28/28 isolates) and Slovenia (85.7%, 82/96) and C. parapsilosis in Croatia (80.6%, 54/67) and Italy (72.6%, 106/146). Echinocandin and polyene resistance rates were nearly zero. The number of isolates included in the surveillance systems increased over the years, particularly for C. albicans (+40-60 isolates/year), C. glabrata, and C. parapsilosis (+15-30 isolates/year). No surveillance system or study reported resistance data for C. auris. Pooled data from national surveillance revealed a decreasing trend in azole resistance in C. albicans and C. glabrata. The increasing azole-resistance trend in C. parapsilosis disappeared after adjusting for between-country heterogeneity. Overall, echinocandin and polyene resistance trends appeared relatively stable.

CONCLUSIONS

Awareness of antifungal resistance is growing, but further actions are needed to strengthen surveillance capacity and knowledge-sharing networks across Europe.

Stephanoascus ciferrii Complex: The Current State of Infections and Drug Resistance in Humans

In recent years, the incidence of fungal infections in humans has increased dramatically, accompanied by an expansion in the number of species implicated as etiological agents, especially environmental fungi never involved before in human infection. Among fungal pathogens, Candida species are the most common opportunistic fungi that can cause local and systemic infections, especially in immunocompromised individuals. Candida albicans (C. albicans) is the most common causative agent of mucosal and healthcare-associated systemic infections. However, during recent decades, there has been a worrying increase in the number of emerging multi-drug-resistant non-albicans Candida (NAC) species, i.e., C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, C. auris, and C. ciferrii. In particular, Candida ciferrii, also known as Stephanoascus ciferrii or Trichomonascus ciferrii, is a heterothallic ascomycete yeast-like fungus that has received attention in recent decades as a cause of local and systemic fungal diseases. Today, the new definition of the S. ciferrii complex, which consists of S. ciferrii, Candida allociferrii, and Candida mucifera, was proposed after sequencing the 18S rRNA gene. Currently, the S. ciferrii complex is mostly associated with non-severe ear and eye infections, although a few cases of severe candidemia have been reported in immunocompromised individuals. Low susceptibility to currently available antifungal drugs is a rising concern, especially in NAC species. In this regard, a high rate of resistance to azoles and more recently also to echinocandins has emerged in the S. ciferrii complex. This review focuses on epidemiological, biological, and clinical aspects of the S. ciferrii complex, including its pathogenicity and drug resistance.

Helium Cold Atmospheric Plasma Causes Morphological and Biochemical Alterations in Candida albicans Cells

(1) Background: Previous studies reported the promising inhibitory effect of cold atmospheric plasma (CAP) on Candida albicans. However, the exact mechanisms of CAP's action on the fungal cell are still poorly understood. This study aims to elucidate the CAP effect on C. albicans cell wall, by evaluating the alterations on its structure and biochemical composition; (2) Methods: C. albicans cells treated with Helium-CAP were analyzed by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) in order to detect morphological, topographic and biochemical changes in the fungal cell wall. Cells treated with caspofungin were also analyzed for comparative purposes; (3) Results: Expressive morphological and topographic changes, such as increased roughness and shape modification, were observed in the cells after CAP exposure. The alterations detected were similar to those observed after the treatment with caspofungin. The main biochemical changes occurred in polysaccharides content, and an overall decrease in glucans and an increase in chitin synthesis were detected; (4) Conclusions: Helium-CAP caused morphological and topographic alterations in C. albicans cells and affected the cell wall polysaccharide content.

Molecular identification, characterization, and antagonistic activity profiling of Bacillus cereus LOCK 1002 along with the in-silico analysis of its presumptive bacteriocins

Objectives

This research aimed to isolate, identify, and characterize a new strain of Bacillus cereus through different molecular biology approaches so that it could be further studied for therapeutic purposes against selective enteric pathogens.

Materials and Methods

Pure isolates of B. cereus were prepared from buffalo yogurt samples in REMBA medium. Initially, the morphological, physiological, and biochemical properties were studied accordingly. Following the tests, the molecular identification for the strain identification was conducted through plasmid DNA extraction, PCR, agarose gel electrophoresis, and 16S rRNA sequencing up to 1.37 kb. Afterward, the antibiotic sensitivity [Epsilometer test (E-Test)] and antifungal activity were tested considering different concentrations. Being classified from the aforementioned tests, a comprehensive antimicrobial activity test was conducted using the cell-free-supernatant (CFS) of the test strain against selective enteric pathogens in humans in vitro. Besides, the different clusters of genes were identified and characterized for understanding the presumptive bacteriocins present in the CFS of the strain in silico, where molecular string properties were calculated. Finally, the evolutionary relationship among diversified bacteriocins synthesized by different Bacillus strains was studied to predict the CFS-containing bacteriocins of the new strain.

Results

Purified isolates of B. cereus were Gram-positive rods and showed significant tolerance (p < 0.0001) to different concentrations of pH, phenol, bile salt, and NaCl. 16S rRNA revealed the strain as LOCK 1002, which was strongly sensitive to all the antibiotics used and resistant to selective antifungal agents. The CFS of B. cereus LOCK 1002 was found to be a very promising antagonist to all the enteric pathogens used in the culture condition. Two gene clusters were predicted to be interconnected and responsible for different presumptive bacteriocins.

Conclusion

The newly identified LOCK 1002 can be a very potent strain of B. cereus in use as an antimicrobial agent for having different bacteriocin coding gene clusters.

Characteristics of antifungal utilization for hospitalized children in the United States

Objective

To characterize antifungal prescribing patterns, including the indication for antifungal use, in hospitalized children across the United States.

Design

We analyzed antifungal prescribing data from 32 hospitals that participated in the SHARPS Antibiotic Resistance, Prescribing, and Efficacy among Children (SHARPEC) study, a cross-sectional point-prevalence survey conducted between June 2016 and December 2017.

Methods

Inpatients aged <18 years with an active systemic antifungal order were included in the analysis. We classified antifungal prescribing by indication (ie, prophylaxis, empiric, targeted), and we compared the proportion of patients in each category based on patient and antifungal characteristics.

Results

Among 34,927 surveyed patients, 2,095 (6%) received at least 1 systemic antifungal and there were 2,207 antifungal prescriptions. Most patients had an underlying oncology or bone marrow transplant diagnosis (57%) or were premature (13%). The most prescribed antifungal was fluconazole (48%) and the most common indication for antifungal use was prophylaxis (64%). Of 2,095 patients receiving antifungals, 79 (4%) were prescribed >1 antifungal, most often as targeted therapy (48%). The antifungal prescribing rate ranged from 13.6 to 131.2 antifungals per 1,000 patients across hospitals (P < .001).

Conclusions

Most antifungal use in hospitalized children was for prophylaxis, and the rate of antifungal prescribing varied significantly across hospitals. Potential targets for antifungal stewardship efforts include high-risk, high-utilization populations, such as oncology and bone marrow transplant patients, and specific patterns of utilization, including prophylactic and combination antifungal therapy.

Hydrothermal assisted biogenic synthesis of silver nanoparticles: A potential study on virulent candida isolates from COVID-19 patients

Till now the exact mechanism and effect of biogenic silver nanoparticles on fungus is an indefinable question. To focus on this issue, the first time we prepared hydrothermal assisted thyme coated silver nanoparticles (T/AgNPs) and their toxic effect on Candida isolates were determined. The role of thyme (Thymus Vulgaris) in the reduction of silver ions and stabilization of T/AgNPs was estimated by Fourier transforms infrared spectroscopy, structure and size of present silver nanoparticles were detected via atomic force microscopy as well as high-resolution transmission electron microscopy. The biological activity of T/AgNPs was observed against Candida isolates from COVID-19 Patients. Testing of virulence of Candida species using Multiplex PCR. T/AgNPs proved highly effective against Candida albicans, Candida kruzei, Candida glabrata and MIC values ranging from 156.25 to 1,250 μg/mL and MFC values ranging from 312.5 to 5,000 μg/mL. The structural and morphological modifications due to T/AgNPs on Candida albicans were detected by TEM. It was highly observed that when Candida albicans cells were subjected to 50 and 100 μg/mL T/AgNPs, a remarkable change in the cell wall and cell membrane was observed.

Creation and Internal Validation of a Clinical Predictive Model for Fluconazole Resistance in Patients With Candida Bloodstream Infection

Background

Fluconazole is recommended as first-line therapy for candidemia when risk of fluconazole resistance (fluc-R) is low. Lack of methods to estimate resistance risk results in extended use of echinocandins and prolonged hospitalization. This study aimed to develop a clinical predictive model to identify patients at low risk for fluc-R where initial or early step-down fluconazole would be appropriate.

Methods

Retrospective analysis of hospitalized adult patients with positive blood culture for Candida spp from 2013 to 2019. Multivariable logistic regression model was performed to identify factors associated with fluc-R. Stepwise regression was performed on bootstrapped samples to test individual variable stability and estimate confidence intervals (CIs). We used receiver operating characteristic curves to assess performance across the probability spectrum.

Results

We identified 539 adults with candidemia and 72 Candida isolates (13.4%) were fluc-R. Increased risk of fluc-R was associated with older age, prior bacterial bloodstream infection (odds ratio [OR], 2.02 [95% CI, 1.13-3.63]), myelodysplastic syndrome (OR, 3.09 [95% CI, 1.13-8.44]), receipt of azole therapy (OR, 5.42 [95% CI, 2.90-10.1]) within 1 year of index blood culture, and history of bone marrow or stem cell transplant (OR, 2.81 [95% CI, 1.41-5.63]). The model had good discrimination (optimism-corrected c-statistic 0.771), and all of the selected variables were stable. The prediction model had a negative predictive value of 95.7% for the selected sensitivity cutoff of 90.3%.

Conclusions

This model is a potential tool for identifying patients at low risk for fluc-R candidemia to receive first-line or early step-down fluconazole.

High frequency of Candida krusei colonization in critically ill pediatrics: A cross-sectional study in children's medical center, Tehran, Iran

Background and Purpose

This study aimed to evaluate the species distribution and susceptibility pattern of the strains isolated from Candida colonization in pediatric patients staying at pediatric intensive care unit (ICU) and infant ICU of Children's Medical Center in Tehran, Iran.

Materials and Methods

This study was conducted in the Children's Medical Center in Tehran, Iran. In total, 440 samples from 56 patients with oral cavity, skin surrounded catheters, and ear, throat, nasal, and urine cultures were collected. All patients were evaluated in terms of Candida colonization on the admission day as well as the days 7, 14, and 28 according to the previous studies. CHROMagar Candida medium was applied for primary/multiple species identification and the isolates were identified by using polymerase chain reaction-based methods to the species-specific complex level. The antifungal susceptibility test was performed according to the Clinical and Laboratory Standards protocol published as M27-A3 and M60 documents.

Results

In total, 136 yeast samples from 26 individuals (30.9%) out of 440 samples were considered colonization. The most prevalent species in IICU was C. albicans (27%, n=20) followed by C. krusei (24 %, n=18) and C. parapsilosis (16%, n=12). In PICU, the predominant species was C. krusei (40%, n=24) followed by C. parapsilosis (18%, n=11) and C. dubliniensis (16%, n=10). Among the 40 tested isolates from both units, fluconazole-resistant isolates (n=11, 8.15%) were determined according to the new breakpoints. In the case of echinocandins, 2 isolates, including C. albicans (n=1) and C. krusei (n=1) were resistant against both caspofungin and anidulafungin (totally 1.48%).

Conclusion

In the present study, since C. krusei is intrinsically-resistance against fluconazole, emphasizing the importance of species-level identification of Candida isolates is outstanding. However, according to the antifungal susceptibility testing results, only 7.2% of the strains were resistant to fluconazole. It would be beneficial to monitor the ICU patients who are at high risk of invasive Candida infection.

Surveillance of Antifungal Resistance in Candidemia Fails to Inform Antifungal Stewardship in European Countries

Background: The increasing burden of candidemia and the emergence of resistance, especially among non-Candida albicans strains, represent a new threat for public health. We aimed to assess the status of surveillance and to identify publicly accessible resistance data in Candida spp blood isolates from surveillance systems and epidemiological studies in 28 European and 4 European Free Trade Association member states. Methods: A systematic review of national and international surveillance networks, from 2015 to 2020, and peer-reviewed epidemiological surveillance studies, from 2005 to 2020, lasting for at least 12 consecutive months and with at least two centers involved, was completed to assess reporting of resistance to amphotericin B, azoles, and echinocandins in C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, and C. auris. Results: Only 5 (Austria, Italy, Norway, Spain, and United Kingdom) of 32 countries provided resistance data for Candida spp blood isolates. Among 322 surveillance studies identified, 19 were included from Belgium, Denmark, Iceland, Italy, Portugal, Spain, Sweden, Switzerland, and United Kingdom. C. albicans and C. glabrata were the most monitored species, followed by C. parapsilosis and C. tropicalis. C. krusei was not included in any national surveillance system; 13 studies assessed resistance. No surveillance system or study reported resistance for C. auris. Fluconazole, voriconazole, caspofungin, and amphotericin B resistance in C. albicans, C. glabrata, and C. parapsilosis were the most common drug–species combination monitored. Quality of surveillance data was poor, with only two surveillance systems reporting microbiological methods and clinical data. High heterogeneity was observed in modalities of reporting, data collection, and definitions. Conclusion: Surveillance of antifungal resistance in Candida spp blood-isolates is fragmented and heterogeneous, delaying the application of a translational approach to the threat of antifungal resistance and the identification of proper targets for antifungal stewardship activities. International efforts are needed to implement antifungal resistance surveillance programs in order to adequately monitor antifungal resistance.

Antifungal Resistance of Candida Species Isolated from HIV Patients in a Tertiary Care Hospital, Mysuru, Karnataka

Context:

Candidiasis still remains as a common opportunistic infection in patients with human immunodeficiency virus (HIV). Drug resistance has become a serious health concern because of indiscriminate usage and dosage.

Aim:

To determine the antifungal resistance pattern of Candida albicans and non-albicans Candida (NAC) from HIV patients.

Subjects and Methods:

The study was carried out in the department of microbiology at a tertiary care hospital. Candida isolates obtained from HIV patients were tested for drug susceptibility by Vitek-2 automated system.

Results:

Antifungal susceptibility pattern (n=109) revealed that 15% of the isolates were resistant to at-least one and 85% were sensitive to all the drugs tested. About 10% and 19% of C. albicans showed resistance to fluconazole and flucytosine respectively. Among non-albicans tested, only C. tropicalis (14%) exhibited resistance to flucytosine.

Conclusions:

Knowledge on epidemiology, species prevalence, and drug resistance pattern may guide for effective therapy. This reduces morbidity and also improves the quality of life.

Species Distribution and Antifungal Susceptibility of Invasive Candidiasis: A 2016-2017 Multicenter Surveillance Study in Beijing, China

OBJECTIVE

Invasive candidiasis (IC), a life-threatening fungal infection prevalent among hospitalized patients, has highly variable regional epidemiology. We conducted a multicenter surveillance study to investigate recent trends in species distribution and antifungal susceptibility patterns among IC-associated Candida spp. in Beijing, China, from 2016 to 2017.

MATERIALS AND METHODS

A total of 1496 non-duplicate Candida isolates, recovered from blood and other sterile body fluids of IC patients, were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry combined with ribosomal DNA internal transcribed spacer (ITS) region sequencing. Broth microdilution-based susceptibility testing using six antifungal agents was also conducted.

RESULTS

Candida albicans was the most frequently isolated species (49.9%), followed by Candida tropicalis (15.5%), Candida glabrata (14.7%) and Candida parapsilosis (14.2%). No significant differences in species distribution were observed when compared with a 2012-2013 dataset. Overall, the rates of susceptibility to fluconazole and voriconazole were high among C. albicans (98% and 97.2%, respectively) and C. parapsilosis species complex (91.1% and 92%, respectively) isolates but low among C. tropicalis (81.5% and 81.1%, respectively) isolates. In addition, the rate of azole resistance among C. tropicalis isolates increased significantly (1.8-fold, P<0.05) compared with that observed in 2012-2013, while micafungin resistance rates were <5% for all tested Candida species.

CONCLUSION

Our results suggest that species distribution has remained stable among IC-associated Candida isolates in Beijing. Resistance to micafungin was rare, but increased azole resistance among C. tropicalis isolates was noted. Our study provides information on local epidemiology that will be important for the selection of empirical antifungal agents and contributes to global assessments of antifungal resistance.

The current state of antifungal stewardship among pediatric antimicrobial stewardship programs

OBJECTIVE

To characterize the current state of antifungal stewardship practices and perceptions of antifungal use among pediatric antimicrobial stewardship programs (ASPs).

DESIGN

We developed and distributed an electronic survey, which included 17 closed-ended questions about institutional antifungal stewardship practices and perceptions, among pediatric ASPs.

PARTICIPANTS

ASP physicians and pharmacists of 74 hospitals participating in the multicenter Sharing Antimicrobial Reports for Pediatric Stewardship (SHARPS) Collaborative.

RESULTS

We sent surveys to 74 hospitals and received 68 unique responses, for a response rate of 92%. Overall, 63 of 68 the respondent ASPs (93%) reported that they conduct 1 or more antifungal stewardship activities. Of these 68 hospital ASPs, 43 (63%) perform prospective audit and feedback (PAF) of antifungals. The most common reasons reported for not performing PAF of antifungals were not enough time or resources (19 of 25, 76%) and minimal institutional antifungal use (6 of 25, 24%). Also, 52 hospitals (76%) require preauthorization for 1 or more antifungal agents. The most commonly restricted antifungals were isavuconazole (42 of 52 hospitals, 80%) and posaconazole (39 of 52 hospitals, 75%). Furthermore, 33 ASPs (48%) agreed or strongly agreed that antifungals are inappropriately used at their institution, and only 25 of 68 (37%) of ASPs felt very confident making recommendations about antifungals.

CONCLUSIONS

Most pediatric ASPs steward antifungals, but the strategies employed are highly variable across surveyed institutions. Although nearly half of respondents identified inappropriate antifungal use as a problem at their institution, most ASPs do not feel confident making recommendations about antifungals. Future studies are needed to determine the rate of inappropriate antifungal use and the best antifungal stewardship strategies.

Difficult to Treat Infections in the Burn Patient

Background: Unusual infections can lead to complications in more severely burned patients and pose major challenges in treatment. Methods: The published literature of retrospective reviews and case series of the uncommon infections of osteomyelitis, polymicrobial bacteremia, recurrent bacteremia, endocarditis, central nervous system (CNS), and rare fungal infections in burned patients have been summarized and presented. Results: When compared with infections occurring in the non-burn population, these infections in burn patients are more likely to be because of gram-negative bacteria or fungi. Because of hyperdynamic physiology and changes in immunomodulatory response secondary to burns, the clinical presentation of these infections in a patient with major burns differs from that of the non-burn patient and may not be identified until the post-mortem examination. Some of these infections (osteomyelitis, endocarditis, CNS, rare fungal infections) may necessitate surgical intervention in addition to antimicrobial therapy to achieve cure. The presence of the burn and allograft can also present unique challenges for surgical management. Conclusions: These difficult and unusual infections in the severely burned patient necessitate an index of suspicion, appropriate diagnosis, identification and sensitivities of the putative pathogen, effective systemic antimicrobial therapy, and appropriate surgical intervention if recovery is to be achieved.

Antifungal resistance in patients with Candidaemia: a retrospective cohort study

Background

Candidaemia is the most common form of invasive candidiasis. Resistant Candida blood stream infection (BSI) is rising, with limitations on the development of broader-spectrum antifungal agents worldwide. Our study aimed to identify the occurrence of antifungal-resistant candidaemia and the distribution of these species, determine the risk factors associated with antifungal resistance and evaluate the association of antifungal-resistant candidaemia with the length of intensive care unit (ICU) and hospital stay and with 30-day mortality.

Methods

A retrospective cohort study was conducted at King Faisal Specialist Hospital and Research Centre, Jeddah, Saudi Arabia. Adult patients diagnosed with candidaemia from January 2006 to December 2017 were included.

Results

A total of 196 BSIs were identified in 94 males (49.74%) and 95 females (50.26%). C. glabrata was the most commonly isolated Candida species, with 59 (30%), followed by C. albicans with 46 (23%). Susceptibility data were available for 122/189 patients, of whom 26/122 (21%) were resistant to one or more antifungals. C. parapsilosis with available sensitivity data were found in 30/122 isolates, of which 10/30 (33%) were resistant to fluconazole. Risk factors significantly associated with antifungal-resistant candidaemia included previous echinocandin exposure (odds ratio (OR) =1.38; 95% confidence interval (CI) (1.02–1.85); P = 0.006) and invasive ventilation (OR = 1.3; 95% CI (1.08–1.57); P = 0.005). The median length of ICU stay was 29 days [range 12–49 days] in the antifungal-resistant group and 18 days [range 6.7–37.5 days] in the antifungal-sensitive group (P = 0.28). The median length of hospital stay was 51 days [range 21–138 days] in the antifungal-resistant group and 35 days [range 17–77 days] in the antifungal-sensitive group (P = 0.09). Thirty-day mortality was 15 (57.7%) and 54 (56.25%) among the antifungal-resistant and antifungal-sensitive groups, respectively (OR = 1.01; 95% CI (0.84–1.21); P = 0.89).

Conclusions

Our results indicate a high frequancy of non- C. albicans candidaemia. The rise in C. parapsilosis resistance to fluconazole is alarming. Further studies are required to confirm this finding.

Support for fungal infection treatment mediated by pharmacist-led antifungal stewardship activities

OBJECTIVE

At the Yokohama General Hospital, pharmacist-led antimicrobial stewardship programs (ASP) including antifungal stewardship programs (AFP) were started in 2012. To investigate the efficacy of the programs, we compared several parameters that are recommended for the measurement of ASP in Japan based on pre- and post-AFP activities.

PATIENTS AND METHODS

The subjects were inpatients who developed candidemia between April 2008 and March 2016. They were divided into two groups: pre-AFP (April 2008 until March 2012) and post-AFP (April 2012 until March 2016). The results were compared between the two groups.

RESULTS

The cumulative optimal antifungal drug usage rate, as a process parameter, significantly increased in the post-AFP group (p = 0.025). Furthermore, the days of therapy of antifungal drugs in the pre- and post-AFP groups was median 6.0 (interquartile range [IQR] 0.3-15.7) and median 3.4 (IQR 1.9-3.4) per 1,000 patient-days, respectively; there was a significant decrease in the post-AFP group (p < 0.001). Expenditure on antifungal drugs, as an outcome parameter, in the pre- and post-AFP groups was 9390.5 ± 5687.1 and 5930.8 ± 4687.0 US dollars, respectively; there was a significant decrease in the post-AFP group (p = 0.002).

CONCLUSIONS

These results suggest that pharmacist-led antifungal stewardship activities improve both outcome and process parameters.

Overview of antifungal dosing in invasive candidiasis

In the past, most antifungal therapy dosing recommendations for invasive candidiasis followed a 'one-size fits all' approach with recommendations for lowering maintenance dosages for some antifungals in the setting of renal or hepatic impairment. A growing body of pharmacokinetic/pharmacodynamic research, however now points to a widespread 'silent epidemic' of antifungal underdosing for invasive candidiasis, especially among critically ill patients or special populations who have altered volume of distribution, protein binding and drug clearance. In this review, we explore how current adult dosing recommendations for antifungal therapy in invasive candidiasis have evolved, and special populations where new approaches to dose optimization or therapeutic drug monitoring may be needed, especially in light of increasing antifungal resistance among Candida spp.

Clonal Spread of Candida glabrata Bloodstream Isolates and Fluconazole Resistance Affected by Prolonged Exposure: a 12-Year Single-Center Study in Belgium

Candida glabrata is a major cause of candidemia in immunocompromised patients and is characterized by a high-level of fluconazole resistance. In the present study, the acquisition of antifungal resistance and potential clonal spread of C. glabrata were explored at a single center over a 12-year period by analyzing 187 independent clinical C. glabrata bloodstream isolates. One strain was found to be micafungin resistant due to a mutation in the FKS2 gene. Fluconazole resistance remained stable throughout the period and was observed in 20 (10.7%) of the isolates. An analysis of the antifungal consumption data revealed that recent prior exposure to fluconazole increased the risk to be infected by a resistant strain. In particular, the duration of the treatment was significantly longer for patients infected by a resistant isolate, while the total and mean daily doses received did not impact the acquisition of resistance in C. glabrata No link between genotype and resistance was found. However, multilocus variable-number tandem-repeat analyses indicated a potential intrahospital spread of some isolates between patients. These isolates shared the same genetic profiles, and infected patients were hospitalized in the same unit during an overlapping period. Finally, quantitative real-time PCR analyses showed that, unlike that for other ABC efflux pumps, the expression of CgCDR1 was significantly greater in resistant strains, suggesting that it would be more involved in fluconazole (FLC) resistance. Our study provides additional evidence that the proper administration of fluconazole is required to limit resistance and that strict hand hygiene is necessary to avoid the possible spreading of C. glabrata isolates between patients.

Overtreatment of Asymptomatic Candiduria among Hospitalized Patients: a Multi-institutional Study

Candiduria is common in hospitalized patients, and asymptomatic candiduria contributes to antifungal overuse. The guidelines for management of asymptomatic candiduria do not recommend antifungal use, but rather the elimination of predisposing factors. It is unknown whether these recommendations are being followed. The primary objective of this study was to characterize candiduria management among hospitalized patients. This was a retrospective cohort study of a random sample of 305 hospitalized patients with candiduria at four U.S. medical centers from January 2010 to December 2013. Patients were classified as asymptomatic or symptomatic based on established criteria, and data were collected by chart review. Infectious Diseases Society of America (IDSA) treatment guideline adherence and its association with clinical outcomes, including candiduria recurrence (short- and long-term) and 30-day readmission, were assessed. Eighty percent of patients were classified as having asymptomatic candiduria. Overall, 143 (47%) patients were not managed according to recommended guidelines, including 105/243 (43%) in the asymptomatic candiduria group and 38/62 (61%) in the symptomatic group (P = 0.01). Discordance among asymptomatic patients was driven by overtreatment with an antifungal (98/105 [93%]). Thirty-three percent of patients with asymptomatic candiduria not managed according to the guidelines were treated for over 7 days, and 5% received over 14 days of therapy. Fluconazole was the most commonly used empirical antifungal among asymptomatic candiduria patients (96%), followed by micafungin (4%). Asymptomatic candiduria patients not managed according to the guidelines had a trend toward higher 30-day readmission (35% versus 26%, P = 0.27). Inappropriate management of candiduria among hospitalized patients was high, leading to overtreatment with antifungal therapy.

The hidden pathogenic potential of environmental fungi

Invasive fungal infections are a growing threat to immunocompromised patients, highlighting the importance of monitoring fungal pathogens. Global warming (including climatic oscillations) may select for environmental species that have acquired thermotolerance, a key step toward pathogenesis to humans. Also, important virulence factors have developed in environmental fungi, because they are essential for yeast survival in the environment. Thus, fungi traditionally regarded as nonpathogenic to humans have virulence factors similar to those of their pathogenic relatives. Here, we highlight the emergence of saprophytic environmental fungi - including species of Cryptococcus, Aspergillus, Penicillium, Candida and Scedosporium - as new human pathogens. Emerging pathogens are, in some cases, resistant to the available antifungals, potentiating the threat of novel fungal diseases.

Antifungal stewardship considerations for adults and pediatrics

Antifungal stewardship refers to coordinated interventions to monitor and direct the appropriate use of antifungal agents in order to achieve the best clinical outcomes and minimize selective pressure and adverse events. Antifungal utilization has steadily risen over time in concert with the increase in number of immunocompromised adults and children at risk for invasive fungal infections (IFI). Challenges in diagnosing IFI often lead to delays in treatment and poorer outcomes. There are also emerging data linking prior antifungal exposure and suboptimal dosing to the emergence of antifungal resistance, particularly for Candida. Antimicrobial stewardship programs can take a multi-pronged bundle approach to ensure suitable prescribing of antifungals via post-prescription review and feedback and/or prior authorization. Institutional guidelines can also be developed to guide diagnostic testing in at-risk populations; appropriate choice, dose, and duration of antifungal agent; therapeutic drug monitoring; and opportunities for de-escalation and intravenous-to-oral conversion.

Dosing of caspofungin based on a pharmacokinetic/pharmacodynamic index for the treatment of invasive fungal infections in critically ill patients on continuous venovenous haemodiafiltration

INTRODUCTION

The study objective was to evaluate the efficacy of different dosages of caspofungin in the treatment of invasive candidiasis and aspergillosis, in relation to the probability of pharmacokinetic/pharmacodynamic (PK/PD) target attainment, using modelling and Monte Carlo simulations in critically ill adult patients on continuous haemodiafiltration.

METHODS

Critically ill adult patients on continuous venovenous haemodiafiltration treated with caspofungin were analysed. A population PK model was developed. Four caspofungin dosing regimens were simulated: the licensed regimen, 70 mg/day, 100 mg/day or 200 mg/day. A PK/PD target was defined as the ratio between the area under the caspofungin concentration-time curve over 24 hours and the minimal inhibitory concentration (AUC/MIC) for candidiasis or the minimal effective concentrations (AUC/MEC) for Aspergillus spp. Target attainment based on preclinical target for Candida and Aspergillus was assessed for different MIC or MEC, respectively.

RESULTS

Concentration-time data were described by a two-compartment model. Body-weight and protein concentration were the only covariates identified by the model. Goodness-of-fit plots and bootstrap analysis proved the model had a satisfactory performance. As expected, a higher maintenance dose resulted in a higher exposure. Target attainment was >90% for candidiasis (MIC≤0.06 mg/L) and aspergillosis (MEC≤0.5 mg/L), irrespective of the dosing regimen, but not for C. parapsilosis. Standard regimen was insufficient to reach the target for C. albicans and C. parapsilosis with MIC≥0.1 mg/L.

CONCLUSION

The licensed regimen of caspofungin is insufficient to achieve the PK/PD targets in critically ill patients on haemodiafiltration. The determination of MICs will enable dose scheme selection.

Bibliometric analysis of literature on antifungal triazole resistance: 1980 - 2015

BACKGROUND

Triazole antifungal agents play an important role in the treatment of a wide range of fungal infections. Little is known about antifungal triazole drug resistance when compared to antibiotic resistance. Therefore, this study was carried out to give a bibliometric overview of literature on triazole antifungal drug resistance.

METHODS

Keywords related to triazole drug class and resistance were used in a search query in the Scopus search engine. The time span was set from 1980 to 2015. Data pertaining to growth of publications, the most active countries and institutions, the most cited articles, and mapping of molecular mechanisms of resistance were analyzed.

RESULTS

A total of 1648 journal articles were retrieved with an average of 20.46 citations per article. Annual growth of triazole resistance showed an increasing pattern during the study period. The United States of America (n=446; 27.06%) ranked first in productivity followed by the United Kingdom (UK) (n=176; 10.68%), and China (n=133; 8.07%). Radboud University Nijmegen Medical Centre (n=69, 4.19%) in the Netherlands ranked first in productivity, while the journal Antimicrobial Agents and Chemotherapy ranked first (n=255; 15.47%) in publishing articles on triazole resistance. Mapping mechanisms of resistance showed that efflux pump and mutations in target enzyme are major mechanisms described in resistance to triazoles.

CONCLUSION

There was a growth of publications on triazole resistance in the past two decades with the bulk of publications on triazole resistance in Candida species. The data presented here will serve as baseline information for future comparative purposes.

Blad-Containing Oligomer Fungicidal Activity on Human Pathogenic Yeasts. From the Outside to the Inside of the Target Cell

Blad polypeptide comprises residues 109-281 of Lupinus albus β-conglutin precursor. It occurs naturally as a major subunit of an edible, 210 kDa oligomer which accumulates to high levels, exclusively in the cotyledons of Lupinus seedlings between the 4th and 14th day after the onset of germination. Blad-containing oligomer (BCO) exhibits a potent and broad spectrum fungicide activity toward plant pathogens and is now on sale in the US under the tradename FractureTM. In this work we demonstrate its antifungal activity toward human pathogens and provide some insights on its mode of action. BCO bioactivity was evaluated in eight yeast species and compared to that of amphotericin B (AMB). BCO behaved similarly to AMB in what concerns both cellular inhibition and cellular death. As a lectin, BCO binds strongly to chitin. In addition, BCO is known to possess 'exochitinase' and 'endochitosanase' activities. However, no clear disruption was visualized at the cell wall after exposure to a lethal BCO concentration, except in cell buds. Immunofluorescent and immunogold labeling clearly indicate that BCO enters the cell, and membrane destabilization was also demonstrated. The absence of haemolytic activity, its biological origin, and its extraordinary antifungal activity are the major outcomes of this work, and provide a solid background for a future application as a new antifungal therapeutic drug. Furthermore, its predictable multisite mode of action suggests a low risk of inducing resistance mechanisms, which are now a major problem with other currently available antifungal drugs.

Identification of Ebsulfur Analogues with Broad-Spectrum Antifungal Activity

Invasive fungal infections are on the rise due to an increased population of critically ill patients as a result of HIV infections, chemotherapies, and organ transplantations. Current antifungal drugs are helpful, but are insufficient in addressing the problem of drug-resistant fungal infections. Thus, there is a growing need for novel antimycotics that are safe and effective. The ebselen scaffold has been evaluated in clinical trials and has been shown to be safe in humans. This makes ebselen an attractive scaffold for facile translation from bench to bedside. We recently reported a library of ebselen-inspired ebsulfur analogues with antibacterial properties, but their antifungal activity has not been characterized. In this study, we repurposed ebselen, ebsulfur, and 32 additional ebsulfur analogues as antifungal agents by evaluating their antifungal activity against a panel of 13 clinically relevant fungal strains. The effect of induction of reactive oxygen species (ROS) by three of these compounds was evaluated. Their hemolytic and cytotoxicity activities were also determined using mouse erythrocytes and mammalian cells. The MIC values of these compounds were found to be in the range of 0.02-12.5 μg mL(-1) against the fungal strains tested. Notably, yeast cells treated with our compounds showed an accumulation of ROS, which may further contribute to the growth-inhibitory effect against fungi. This study provides new lead compounds for the development of antimycotic agents.

Posttreatment Antifungal Resistance among Colonizing Candida Isolates in Candidemia Patients: Results from a Systematic Multicenter Study

The prevalence of intrinsic and acquired resistance among colonizing Candida isolates from patients after candidemia was investigated systematically in a 1-year nationwide study. Patients were treated at the discretion of the treating physician. Oral swabs were obtained after treatment. Species distributions and MIC data were investigated for blood and posttreatment oral isolates from patients exposed to either azoles or echinocandins for <7 or ≥ 7 days. Species identification was confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and internal transcribed spacer (ITS) sequencing, susceptibility was examined by EUCAST EDef 7.2 methodology, echinocandin resistance was examined by FKS sequencing, and genetic relatedness was examined by multilocus sequence typing (MLST). One hundred ninety-three episodes provided 205 blood and 220 oral isolates. MLST analysis demonstrated a genetic relationship for 90% of all paired blood and oral isolates. Patients exposed to azoles for ≥ 7 days (n = 93) had a significantly larger proportion of species intrinsically less susceptible to azoles (particularly Candida glabrata) among oral isolates than among initial blood isolates (36.6% versus 12.9%; P < 0.001). A similar shift toward species less susceptible to echinocandins among 85 patients exposed to echinocandins for ≥ 7 days was not observed (4.8% of oral isolates versus 3.2% of blood isolates; P > 0.5). Acquired resistance in Candida albicans was rare (<5%). However, acquired resistance to fluconazole (29.4%; P < 0.05) and anidulafungin (21.6%; P < 0.05) was common in C. glabrata isolates from patients exposed to either azoles or echinocandins. Our findings suggest that the colonizing mucosal microbiota may be an unrecognized reservoir of resistant Candida species, especially C. glabrata, following treatment for candidemia. The resistance rates were high, raising concern in general for patients exposed to antifungal drugs.

Development of fluconazole resistance in a series of Candida parapsilosis isolates from a persistent candidemia patient with prolonged antifungal therapy

Background

Candida parapsilosis was the most common species causing candidemia in the 2010 China Hospital Invasive Fungal Surveillance Net (CHIF-NET) database. Compared to Candida albicans, the description of azole resistance and mechanisms in C. parapsilosis is very limited. We report a patient with C. parapsilosis candidemia over several months, due to a probable intravascular source, who developed fluconazole resistance after prolonged treatment.

Case presentation

An 82 year-old male had a hospital admission of approximately 1.5 years duration. He was initially admitted with acute pancreatitis. Prior to succumbing to the illness, he developed candidemia and treated with three antifungal drugs for nearly 5 months, at suboptimal doses and without source control. Following treatment, 6 blood cultures were still positive for C. parapsilosis. The last 2 strains were resistant to fluconazole (MICs 32 μg/mL) and intermediate to voriconazole (MICs 0.5 μg/mL). Microsatellite multilocus analysis indicated that the 6 isolates from the patient belonged to a single genotype. The first 4 isolates were susceptible to fluconazole (MICs 2 μg/mL) and voriconazole (MICs 0.015-0.03 μg/mL), which were slightly higher than susceptible control strains from other patients. Overexpression of MDR1 genes were detected in the two resistant isolates, and this was associated with a homozygous mutation in MRR1 genes (T2957C /T2957C), with the amino acid exchange L986P.

Conclusions

This case corroborates that the resistant C. parapsilosis isolates can emerge in the setting of complicated infections and the extensive use of antifungal agents, emphasizing the need for standardizing and improving the antifungal treatment as well as source control in the treatment of infection diseases.

Echinocandin use in hospitalized patients: a multi-institutional study

BACKGROUND

The echinocandin antifungals are recommended as initial therapy in hospitalized patients with candidemia. Contemporary usage rates and indication for use of echinocandins have not been studied in the United States. The purpose of this study was to evaluate echinocandin usage patterns in community and academic teaching hospitals over time and to evaluate dose, duration of therapy and indications for use.

METHODS

This study used hospital pharmacy databases from academic and community hospitals to collect information on adult inpatients given systemic antifungal agents from 2008 to 2012. Patient medical information was also obtained from randomly selected patients given an echinocandin over the same time period.

RESULTS

Echinocandin use was determined for 4 academic and 34 community hospitals. A significant increase in echinocandin use was observed in academic and community hospitals during the time period (P < 0.001). Two hundred forty-two randomly selected patients receiving an echinocandin were retrospectively reviewed. Indications for echinocandin use did not change during the time period and included empiric therapy in a high-risk patient without subsequent mycologic confirmation from a normally sterile site (55%), systemic candidiasis (43%) and prophylactic (2%). Fifty-six percent of patients had at least 1 anatomic site of mycologic growth; most commonly urine only (14%), respiratory only (12%) or blood only (7%). In patients with candidemia, the hospital treatment course with an echinocandin averaged 8.4 ± 7.9 days (range, 1-35 days).

CONCLUSIONS

This study provides useful benchmark data on antifungal use and indications for use that could be used for antifungal stewardship program comparisons.

Antifungal susceptibility profiles of bloodstream yeast isolates by Sensititre YeastOne over nine years at a large Italian teaching hospital

Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, the MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or the wild-type [WT] phenotype) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among the non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 were other species, mainly Rhodotorula species. Over 97% of Candida isolates were susceptible (WT phenotype) to amphotericin B and flucytosine. Rates of susceptibility (WT phenotype) to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in the C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates consisted of 6 C. parapsilosis complex isolates, 3 C. glabrata isolates, 2 C. albicans isolates, 2 C. tropicalis isolates, and 1 Candida lusitaniae isolate. Of the non-Candida isolates, 2 C. neoformans isolates had the non-WT phenotype for susceptibility to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7% to 99.8% of Candida isolates were susceptible (WT phenotype) to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). However, when the intrinsically resistant non-Candida isolates were included, the rate of echinocandin nonsusceptibility reached 1.8%. In summary, the SYO method proved to be able to detect yeast species showing antifungal resistance or reduced susceptibility.

Risk factors for fluconazole-resistant invasive candidiasis in intensive care unit patients: An analysis from the China Survey of Candidiasis study

PURPOSE

To assess the risk factors for invasive Candida infection (ICI) caused by fluconazole-resistant (Flu-R) Candida species in intensive care unit (ICU) patients.

MATERIALS AND METHODS

Data from China Survey of Candidiasis study were analyzed. Patients with proven ICI were classified into fluconazole-sensitive (Flu-S) and Flu-R groups. Independent risk factors for Flu-R ICI were identified using a multivariate logistic regression.

RESULTS

Forty-one percent of ICI patients were infected with Flu-R Candida. Significantly more patients had Candida colonization, intra-abdominal hypertension, and antifungal therapy at least 7 days before diagnosis; fewer patients had gastrointestinal perforation, systemic inflammatory response syndrome manifestation, and fluoroquinolone exposure in the Flu-R group. Furthermore, hospital or ICU stay before onset of infection was longer in the Flu-R group than in the Flu-S group (hospital or ICU stay: 19 vs 13 days or 10.5 vs 8 days, P < .05). Also, it was demonstrated as an independent risk factor for Flu-R Candida infection.

CONCLUSION

As many as 41% of ICI patients were infected with Flu-R Candida, and the main risk factor was longer ICU stay before onset of ICI, implying that caution should be exercised when treating patients who have been long stayed in ICU with fluconazole as the first-line drug before testing isolates for drug sensitivity.

Antifungal susceptibilities of bloodstream isolates of Candida species from nine hospitals in Korea: application of new antifungal breakpoints and relationship to antifungal usage

We applied the new clinical breakpoints (CBPs) of the Clinical and Laboratory Standards Institute (CLSI) to a multicenter study to determine the antifungal susceptibility of bloodstream infection (BSI) isolates of Candida species in Korea, and determined the relationship between the frequency of antifungal-resistant Candida BSI isolates and antifungal use at hospitals. Four hundred and fifty BSI isolates of Candida species were collected over a 1-year period in 2011 from nine hospitals. The susceptibilities of the isolates to four antifungal agents were determined using the CLSI M27 broth microdilution method. By applying the species-specific CBPs, non-susceptibility to fluconazole was found in 16.4% (70/428) of isolates, comprising 2.6% resistant and 13.8% susceptible-dose dependent isolates. However, non-susceptibility to voriconazole, caspofungin, or micafungin was found in 0% (0/370), 0% (0/437), or 0.5% (2/437) of the Candida BSI isolates, respectively. Of the 450 isolates, 72 (16.0%) showed decreased susceptibility to fluconazole [minimum inhibitory concentration (MIC) ≥4 μg/ml]. The total usage of systemic antifungals varied considerably among the hospitals, ranging from 190.0 to 7.7 defined daily dose per 1,000 patient days, and fluconazole was the most commonly prescribed agent (46.3%). By Spearman’s correlation analysis, fluconazole usage did not show a significant correlation with the percentage of fluconazole resistant isolates at hospitals. However, fluconazole usage was significantly correlated with the percentage of fluconazole non-susceptible isolates (r = 0.733; P = 0.025) or the percentage of isolates with decreased susceptibility to fluconazole (MIC ≥4 μg/ml) (r = 0.700; P = 0.036) at hospitals. Our work represents the first South Korean multicenter study demonstrating an association between antifungal use and antifungal resistance among BSI isolates of Candida at hospitals using the new CBPs of the CLSI.

Pharmacokinetic variability and exposures of fluconazole, anidulafungin, and caspofungin in intensive care unit patients: Data from multinational Defining Antibiotic Levels in Intensive care unit (DALI) patients Study

Introduction

The objective of the study was to describe the pharmacokinetics (PK) of fluconazole, anidulafungin, and caspofungin in critically ill patients and to compare with previously published data. We also sought to determine whether contemporary fluconazole doses achieved PK/pharmacodynamic (PD; PK/PD) targets in this cohort of intensive care unit patients.

Methods

The Defining Antibiotic Levels in Intensive care unit patients (DALI) study was a prospective, multicenter point-prevalence PK study. Sixty-eight intensive care units across Europe participated. Inclusion criteria were met by critically ill patients administered fluconazole (n = 15), anidulafungin (n = 9), and caspofungin (n = 7). Three blood samples (peak, mid-dose, and trough) were collected for PK/PD analysis. PK analysis was performed by using a noncompartmental approach.

Results

The mean age, weight, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores of the included patients were 58 years, 84 kg, and 22, respectively. Fluconazole, caspofungin, and anidulafungin showed large interindividual variability in this study. In patients receiving fluconazole, 33% did not attain the PK/PD target, ratio of free drug area under the concentration-time curve from 0 to 24 hours to minimum inhibitory concentration (fAUC_0–24/MIC) ≥100. The fluconazole dose, described in milligrams per kilogram, was found to be significantly associated with achievement of fAUC_0–24/MIC ≥100 (P = 0.0003).

Conclusions

Considerable interindividual variability was observed for fluconazole, anidulafungin, and caspofungin. A large proportion of the patients (33%) receiving fluconazole did not attain the PK/PD target, which might be related to inadequate dosing. For anidulafungin and caspofungin, dose optimization also appears necessary to minimize variability.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0758-3) contains supplementary material, which is available to authorized users.

Presentation and management of mycotic pseudoaneurysm after kidney transplantation

Pseudoaneurysms (PAs) developing at the site of vascular anastomosis after organ transplantation are a rare but serious complication. We report a series of 3 cases of PA observed in a single center over a period of 18 years. The mode of presentation was acute bleeding in 2 cases. In the third patient, who underwent combined kidney and pancreas transplantation, the PA on the renal graft was discovered by chance. Graft removal associated with iliac artery ligation and extra-anatomic femoro-femoral bypass represents the standard treatment. However, interposition of a venous homograft may allow preservation of inferior limb perfusion and possibly graft salvage.

Emergence of echinocandin-resistant Candida spp. in a hospital setting: a consequence of 10 years of increasing use of antifungal therapy?

Since their introduction in the 2000s, echinocandin drugs have become widely used for the treatment and prophylaxis of invasive fungal infections and, notably, invasive candidiasis. Although cases of breakthrough candidiasis in patients receiving echinocandins have been reported, clinical failure during echinocandin treatment due to the acquisition of resistance by a normally susceptible Candida spp. isolate is considered rare. To date, no publications have been published correlating the use of echinocandins and the emergence of echinocandin resistance among Candida species. So, our goal is to report an initial analysis of echinocandin use in relation to the emergence of resistant Candida isolates. We report here a single-centre experience of the emergence of eight resistant isolates belonging to normally susceptible Candida species in six patients receiving echinocandins. We describe the context and analyse the use of echinocandins over the previous decade. For seven of these isolates, we identified FKS gene mutations involved in decreased susceptibility. Seven isolates were obtained in 2011, on the heels of a ten-fold increase in caspofungin use over the preceding decade. In contrast, in 2012, the use of echinocandins decreased in our institution by 19.5 % and, in that year, only one Candida-resistant isolate was detected, despite the stable global epidemiology of invasive candidaemia. This work underlines the necessity of improving the prescription of antifungal drugs. Improvement in the monitoring of strain susceptibility should also be considered in order to better detect the emergence of resistant or non-susceptible yeast strains.

Update on antifungal resistance in Aspergillus and Candida

Antifungal resistance in Candida and Aspergillus may be either intrinsic or acquired and may be encountered in the antifungal drug exposed but also the antifungal drug-naïve patient. Prior antifungal treatment confers a selection pressure and notoriously raises the awareness of possible resistance in patients failing therapy, thus calling for susceptibility testing. On the contrary, antifungal resistance in the drug-naïve patient is less expected and therefore more challenging. This is particularly true when it concerns pathogens with acquired resistance which cannot be predicted from the species identification itself. This scenario is particularly relevant for A. fumigatus infections due to the increasing prevalence of azole-resistant isolates in the environment. For Candida, infections resistance is most common in the context of increasing prevalence of species with intrinsic resistance. Candida glabrata which has intrinsically reduced susceptibility to fluconazole is increasingly common particularly among the adult and elderly population on the Northern Hemisphere where it may be responsible for as many as 30% of the blood stream infections in population-based surveillance programmes. Candida parapsilosis is prevalent in the paediatric setting, at centres with increasing echinocandin use and at the southern or pacific parts of the world. In the following, the prevalence and drivers of intrinsic and acquired resistance in Aspergillus and Candida will be reviewed.

An Italian consensus for invasive candidiasis management (ITALIC)

INTRODUCTION

Invasive candidiasis (IC) has primarily been studied in intensive care unit (ICU) patients, although, in reality, a vast majority of these infections occur outside of the ICU. The recent publication of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guidelines also deal with the non-ICU population, but many uncertainties remain on the management of IC, particularly in non-critically ill patients.

METHODS

The Italian Society of Antimicrobial Therapy, Società Italiana di Terapia Antimicrobica (SITA), produced practical, hospital-wide recommendations on the management of Candida infection in non-immunocompromised patients in the hospital ward.

RESULTS AND DISCUSSION

Our focus is on patient stratification in terms of risk factors for IC and of clinical severity, emphasising a high index of suspicion to ensure early diagnosis, early treatment and de-escalation when a patient is clinically stable, in order to optimise resource allocation.

Comparison of the T2Dx instrument with T2Candida assay and automated blood culture in the detection of Candida species using seeded blood samples

As a delay in the diagnosis and treatment of candidemia is associated with increased mortality and healthcare costs, a more rapid method of detection is urgently needed. The T2Candida assay is a new rapid diagnostic test, which uses T2 magnetic resonance technology to identify Candida spp. directly from whole blood in approximately 3 hours. In this study, the performance of the BACTEC 9050 using Aerobic Plus/F blood culture bottles was compared to that of the T2Candida assay run on the T2Dx Instrument for detection of Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei, in seeded blood samples at concentrations between 3.1 and 11 CFU/mL. The BACTEC 9050 detected Candida growth in 100% of bottles (n = 20 replicates) within 5 days for all species (63.23 ± 30.27 hours), with the exception of Candida glabrata (0%). The T2Candida assay had a 100% detection rate for each species (n = 13-20 replicates) within 3 hours including C. glabrata. The sensitivity and specificity of the T2Candida assay were 1 and 0.978, respectively.

Pediatric Risk Factors for Candidemia Secondary to Candida glabrata and Candida krusei Species

This 13-year retrospective study investigated risk factors for candidemia secondary to Candida species with increased likelihood of fluconazole resistance. Of 344 candidemia cases, 23 were caused by C glabrata or C krusei (CGCK). Age >2 years, recent fluconazole exposure, and recent surgery were independent risk factors for CGCK.

Treatment of Candida famata bloodstream infections: case series and review of the literature

OBJECTIVES

Candida famata (also known as Debaryomyces hansenii and Torulopsis candida) is a commensal yeast found in cheese, dairy products and the environment. C. famata accounts for 0.2%-2% of invasive candidiasis. The purpose of this study was to provide an overview of the treatment of C. famata bloodstream infections.

METHODS

The clinical course of two hospitalized patients who developed C. famata fungaemia within 2 weeks of each other was summarized along with available data regarding in vitro susceptibility patterns, genotyping and clinical outcomes of these cases compared with the published literature.

RESULTS AND CONCLUSIONS

C. famata appears to exhibit reduced susceptibility to echinocandins and azoles, particularly in the setting of prior antifungal exposure. The removal of indwelling central venous catheters and prompt initiation of therapy with liposomal amphotericin B is recommended for successful treatment of C. famata fungaemia, particularly in immunocompromised patients. These cases also help provide justification for routine antifungal susceptibility testing in patients with candidaemia to guide optimal antifungal therapy.