Executive Summary: Clinical Practice Guideline for the Management of Candidiasis: 2016 Update by the Infectious Diseases Society of America

Incidence and risk factors for COVID-19 associated candidemia (CAC) in ICU patients

BACKGROUND

Critically ill COVID-19 patients have a high risk for the development of candidemia due to being exposed to both well-defined classical risk factors and COVID-19-specific risk factors in ICU.

OBJECTIVES

In this study, we investigated the incidence of candidemia in critically COVID-19 patients, and the independent risk factors for candidemia.

PATIENTS/METHODS

COVID-19 patients hospitalised in ICU during 1-year period (August 2020 to August 2021) were included. Clinical and laboratory characteristics of all COVID-19 patients, applied treatments, and invasive procedures that may predispose to candidemia were recorded.

RESULTS

Of 1229 COVID-19 patients, 63 developed candidemia. Candidemia incidence rate was 4.4 episodes per 1000 ICU days. The most common species was Candida albicans (52.3%). Only 37 patients (58.7%) received antifungal therapy. The presence of central venous catheter (OR 4.7, 95% CI 1.8-12.2, p < .005), multifocal candida colonisation (OR 2.7, 95% CI 1.4-5.2, p < .005), a prolonged ICU stay (≥14 days) (OR 1.9, 95% CI 1.08-3-37, p < .05), the absence of chronic lung disease (OR 0.4, 95% CI 0.1-0.9, p < .05) and the absence of corticosteroid use (OR 0.3, 95% CI 0.14-0.52, p < .0001) were significantly associated with candidemia.

CONCLUSIONS

Our study filled the knowledge gap in the literature about the impact of COVID-19-associated risk factors for the development of candidemia. The classical risk factors for candidemia had a significant effect on candidemia, and contrary to expectations, corticosteroids had a protective effect against the development of candidemia. The results of these studies showing interesting effects of corticosteroids in critically ill COVID-19 patients should be confirmed by further studies.

Development and Validation of a Risk Score for Predicting Invasive Candidiasis in Intensive Care Unit Patients by Incorporating Clinical Risk Factors and Lymphocyte Subtyping

Objective

To develop and validate a rapid invasive candidiasis (IC)-predictive risk score in intensive care unit (ICU) patients by incorporating clinical risk factors and parameters of lymphocyte subtyping.

Methods

A prospective cohort study of 1054 consecutive patients admitted to ICU was performed. We assessed the clinical characteristics and parameters of lymphocyte subtyping at the onset of clinical signs of infection and their potential influence on IC diagnosis. A risk score for early diagnosis of IC was developed and validated based on a logistic regression model.

Results

Sixty-nine patients (6.5%) had IC. Patients in the cohort (N=1054) were randomly divided into a development (n=703) or validation (n=351) cohorts. Multivariate logistic regression identified that CD8+ T-cell count ≤143 cells/mm³, receipt of high-dose corticosteroids (dose ≥50 mg prednisolone equivalent), receipt of carbapenem/tigecycline, APACHE II score≥15, (1,3)-β-D-glucan (BDG) positivity and emergency gastrointestinal/hepatobiliary (GIT/HPB) surgery were significantly related with IC. IC risk score was calculated using the following formula: CD8+ T-cell count ≤143 cells/mm³ + receipt of high-dose corticosteroids + receipt of carbapenem/tigecycline + APACHE II score ≥15 + BDG positivity + emergency GIT/HPB surgery ×2. The risk scoring system had good discrimination and calibration with area under the receiver operating characteristic (AUROC) curve of 0.820 and 0.807, and a non-significant Hosmer-Lemeshow test P=0.356 and P=0.531 in the development and validation cohorts, respectively. We categorized patients into three groups according to risk score: low risk (0-2 points), moderate risk (3-4 points) and high risk (5-7 points). IC risk was highly and positively associated with risk score (Pearson contingency coefficient=0.852, P for trend=0.007). Candida score had a moderate predicting efficacy for early IC diagnosis. The AUROC of the risk score was significantly larger than that of Candida score (0.820 versus 0.711, Z=2.013, P=0.044).

Conclusions

The predictive scoring system, which used both clinical factors and CD8+ T cell count, served as a clinically useful predictive model for rapid IC diagnosis in this cohort of ICU patients.

Clinical Trial Registration

chictr.org.cn, identifier ChiCTR-ROC-17010750.

Chronic Candida albicans meningitis misdiagnosed as polymyalgia rheumatica and successfully treated with voriconazole

The outcome of chronic meningitis depends to a large degree on the causative pathogen and the interval between onset of symptoms and diagnosis. We present a patient with a delayed diagnosis and several complications, for whom adequate therapy resulted in a favorable outcome. In a 76-year-old male patient, Candida albicans meningitis was diagnosed 4 months after the onset of symptoms. CSF findings (protein >1000 mg/L, predominance of intrathecal immunoglobulin A synthesis, lactate concentrations of approx. 10 mmol/L, leukocyte counts around 1000/μl, variable differential leukocyte counts) resembled tuberculous meningitis. In spite of the long interval without treatment, voriconazole 200 mg every 12 h for 7 weeks followed by fluconazole 300 mg/day maintenance therapy for 7 months led to a recovery with only mild deficits. The case illustrates that 1. C. albicans can cause chronic meningitis in patients without severe immune defects, 2. patients can survive C. albicans meningitis with mild long-term sequelae even when diagnosis and adequate treatment are delayed, and 3. voriconazole as a sole agent may be suitable for treatment of C. albicans meningitis.

Activity of poly(methacrylic acid)-silver nanoparticles (PMAA-AgNPs) on fluconazole resistant Candida albicans strains: synergistic and cytotoxic effects

AIMS

To synthesize and evaluate the antifungal activity of poly(methacrylic acid)-silver nanoparticles (PMAA-AgNPs) against nine Candida albicans isolated from clinical specimens.

METHODS AND RESULTS

The effects of PMAA-AgNPs-fluconazole combination was analyzed by checkerboard methodology. The synergistic potential of PMAA-AgNPs-fluconazole was determined by the fractional inhibitory concentration index (FICI). The inhibition of germ tube formation and the determination of PMAA-AgNPs cytotoxicity were also performed. All C. albicans strains were susceptible to PMAA-AgNPs and resistant to fluconazole. PMAA-AgNPs at sub-inhibitory concentrations restored the susceptibility of resistant C. albicans to fluconazole, whose FICI ranged from 0.3 to 0.5. The synergistic interaction of the combination was observed in eight of nine strains. The PMAA-AgNPs-fluconazole combination was also able to inhibit the germ tube formation. PMAA-AgNPs showed a dose-dependent decrease on viability for cells tested, with 50% cytotoxic concentration (CC₅₀ ) values of 6.5, 4.9 and 6.8 μg ml^-1 for macrophages, fibroblasts and Vero cells, respectively.

CONCLUSIONS

This study demonstrated that in general, PMAA-AgNPs acts synergistically in combination with fluconazole, inhibiting fluconazole-resistant C. albicans strains. PMAA-AgNPs-fluconazole combination was also able to inhibit germ tube formation, an important virulence factor. Inhibitory effect of PMAA-AgNPs alone or in combination was higher in C. albicans than in mammalian cells.

SIGNIFICANCE AND IMPACT OF STUDY

This study shows the potential of poly(methacrylic acid)-silver nanoparticles combined with fluconazole to inhibit fluconazole-resistant Candida albicans strains.

Screening for ocular candidiasis among patients with candidemia: Is it time to change practice?

Ocular candidiasis (OC) complicates ~10% of candidemia and carries potentially severe morbidity. There are conflicting recommendations about the need for routine funduscopic examinations of candidemic patients. Indirect funduscopy is accurate and safe in diagnosing OC, and positive findings change recommended treatment. However, conclusive evidence is lacking that treatment changes improve outcomes. Bringing perspectives as infectious diseases physicians and ophthalmologists, we review controversies about OC and endorse routine screening during candidemia. We acknowledge difficulties in obtaining inpatient ophthalmologic consults, and recommend studies evaluating digital fundus photography and tele-ophthalmology as an alternative to funduscopic examinations by ophthalmologists in asymptomatic patients.

Fluconazole Population Pharmacokinetics after Fosfluconazole Administration and Dosing Optimization in Extremely Low-Birth-Weight Infants

A prospective single-center study was conducted to characterize the pharmacokinetics (PK) of fluconazole (FLCZ) in extremely low-birth-weight infants (ELBWIs) who received fosfluconazole (F-FLCZ). Intravenous F-FLCZ was administered at a dose of 3 mg/kg of body weight every 72 h during the first 2 weeks of life, every 48 h during the third and fourth weeks of life, and every 24 h after 5 weeks of life. Blood samples from ELBWIs treated with F-FLCZ were collected using scavenged samples. The concentration of FLCZ was determined using liquid chromatography-tandem mass spectrometry. The population pharmacokinetic model was established using Phenix NLME 8.2 software. In total, 18 ELBWIs were included in this analysis. Individual PK parameters were determined by a one-compartment analysis with first-order conversion. Postmenstrual age (PMA), serum creatinine (SCr), and alkaline phosphatase were considered covariates for clearance (CL). The mean population CL and the volume of distribution were 0.011 L/h/kg^0.75 and 0.95 L/kg, respectively. Simulation assessments with the final model revealed that the current regimen (3 mg/kg every 72 h) could achieve the proposed target FLCZ trough concentration (>2 μg/mL) in 43.3% and 72.2% of infants with a PMA of ≥37 and 30 to 36 weeks, respectively, and an SCr level of <0.5 mg/dL. Shortened dosing intervals (every 48 or 24 h) might improve the probability of target attainment. This study was the first to assess the PK of F-FLCZ in ELBWI, as well as the first to provide fundamental information about FLCZ exposure after F-FLCZ administration, with the goal of facilitating dose optimization in the ELBWI population.

IMPORTANCE Invasive fungal infection is an important cause of mortality and morbidity in very preterm or very-low-birth-weight infants. In order to limit the risk of invasive fungal infections in this population, the administration of fluconazole is generally recommended for extremely low-birth-weight infants admitted to a neonatal intensive care unit with a Candida species colonization prevalence rate of >10%, under the guidelines of the Infectious Diseases Society of America. Fosfluconazole can reduce the volume of solution required for intravenous therapy compared to fluconazole because it has increased solubility, which is a major advantage for infants undergoing strict fluid management. To date, no study has demonstrated the fluconazole pharmacokinetics after fosfluconazole administration in neonates and infants, and this needs to be clarified. Here, we characterized the pharmacokinetics of fluconazole in extremely low-birth-weight infants who received F-FLCZ and explored the appropriate dosage in this patient population.

Nonviral Infections of the Liver in Developing Countries

Content available: Author Interview and Audio Recording.

Candidemia in hospitalized cirrhotic patients with bloodstream infection: A retrospective analysis and brief summary of published studies

BACKGROUND

Candidemia is a life-threatening condition; however, the predictive markers for candidemia and mortality are inadequate in cirrhotic patients. This study was conducted to propose candidate predictors for the occurrence of candidemia and 30-day mortality in hospitalized cirrhotic patients with bloodstream infection (BSI) and review the related literature.

METHODS

Cirrhotic patients with BSI between January 2011 and March 2020 were screened from the databank of a medical center and eligible patients were enrolled. Patients were separated into candidemia and bacteremia groups according to the results of blood cultures. Baseline characteristics, clinical presentation, and biochemistry data were collected at this time, as were microbiological data, medical management, use of antimicrobial agents, and outcome of the patients. The parameters and 30-day mortality were compared between candidemia and bacteremia groups. A combination of the MeSH terms and text terms related to candidemia and cirrhosis was searched in the electronic databases.

RESULTS

Four hundred and sixty cirrhotic patients with BSI were enrolled. Thirty-five patients with candidemia (7.6%) were identified. Nosocomial infection, intensive care unit (ICU) admission, antibiotics exposure ≥14 days, white cell count >10 K/mm3, and model for end-stage liver disease (MELD) score >24 were associated with candidemia. The 30-day mortality was 65.7% in the candidemia group and 37.9% in the bacteremia group (p = 0.001). Nosocomial infection, ICU admission, hepatoma, hepatic encephalopathy, international normalized ratio ≥1.2, platelet ≤150 K/mm3, estimated glomerular filtration rate <60 mL/min/1.73m2, and MELD score >24 were associated with 30-day mortality. Six studies were identified. The results were consistent with our findings regarding low incidence of candidemia, and relevant risk factors are listed.

CONCLUSION

Candidemia had low incidence but high mortality in hospitalized cirrhotic patients with BSI. New predictors were proposed for the occurrence of candidemia and 30-day mortality in these patients.

Directing Crystallization Outcomes of Conformationally Flexible Molecules: Polymorphs, Solvates, and Desolvation Pathways of Fluconazole

Control over polymorphism and solvatomorphism in API assisted by structural information, e.g., molecular conformation or associations via hydrogen bonds, is crucial for the industrial development of new drugs, as the crystallization products differ in solubility, dissolution profile, compressibility, or melting temperature. The stability of the final formulation and technological factors of the pharmaceutical powders further emphasize the importance of precise crystallization protocols. This is particularly important when working with highly flexible molecules with considerable conformational freedom and a large number of hydrogen bond donors or acceptors (e.g., fluconazole, FLU). Here, cooling and suspension crystallization were applied to access polymorphs and solvates of FLU, a widely used azole antifungal agent with high molecular flexibility and several reported polymorphs. Each of four polymorphic forms, FLU I, II, III, or IV, can be obtained from the same set of alcohols (MeOH, EtOH, isPrOH) and DMF via careful control of the crystallization conditions. For the first time, two types of isostructural channel solvates of FLU were obtained (nine new structures). Type I solvates were prepared by cooling crystallization in Tol, ACN, DMSO, BuOH, and BuON. Type II solvates formed in DCM, ACN, nPrOH, and BuOH during suspension experiments. We propose desolvation pathways for both types of solvates based on the structural analysis of the newly obtained solvates and their desolvation products. Type I solvates desolvate to FLU form I by hydrogen-bonded chain rearrangements. Type II solvates desolvation leads first to an isomorphic desolvate, followed by a phase transition to FLU form II through hydrogen-bonded dimer rearrangement. Combining solvent-mediated phase transformations with structural analysis and solid-state NMR, supported by periodic electronic structure calculations, allowed us to elucidate the interrelations and transformation pathways of FLU.

Impact of FKS1 Genotype on Echinocandin In Vitro Susceptibility in Candida auris and In Vivo Response in a Murine Model of Infection

Echinocandins are frontline antifungal agents in the management of invasive infections due to multidrug resistant Candida auris. The study aimed to evaluate echinocandin resistance in C. auris isolates of multicentric origin, identify the resistance mechanism, and analyze the pharmacodynamic response to caspofungin in a neutropenic mouse model of infection. A total of 199 C. auris isolates originating from 30 centers across India were tested for susceptibility to echinocandins. Isolates with reduced susceptibility were evaluated for FKS1 mutations and in vivo response to caspofungin in a murine model of disseminated candidiasis. In addition, the response to echinocandins was assessed in light of in vitro growth kinetics, chitin content; and transcript levels of chitin synthase and FKS1 genes. We report 10 resistant C. auris isolates with four FKS1 mutations: F635Y (n = 2), F635L (n = 4), S639F (n = 3), and R1354S (n = 1). Of these, F635Y and R1354S exhibited the most profound resistance in mouse model of disseminated infection. S639F and F635L mutations conferred a moderate in vivo resistance, whereas wild-type isolates exhibiting borderline MIC were susceptible in vivo. FKS1 genotype was more accurate predictor of in vivo response than the MIC of the isolates. Isolates with high basal or inducible chitin content exhibited higher in vitro MIC in FKS1 mutant compared to wild type. FKS1 mutations play a major role in clinically relevant echinocandin resistance in C. auris with differential in vivo outcomes. This study could have implications for clinical practice and, therefore, warrants further studies.

Lower beta-1,3-D-glucan testing cut-offs increase sensitivity for non-albicans Candida species blood stream infections

PURPOSE

Fungal biomarkers support early diagnosis of invasive fungal infections. In this study, we evaluated the impact of a recent update to the manufacturer-recommended cut-off for beta-1,3-D-glucan (BDG) testing (Fujifilm Wako BDG assay) on sensitivity and specificity for the detection of candidemia. Additionally, we compared the performance with tests for Candida antigen (Ag by Serion ELISA antigen Candida, Virion\Serion) and anti-mannan antibodies (Ab by Hemkit Candida IHA, Ravo Diagnostika).

METHODS

Sera of 82 patients with candidemia, which were sampled with a maximum distance of ±14 days from the date of sampling of the corresponding positive blood cultures, were retrospectively analyzed for BDG, Ag, and Ab. Results of BDG testing were compared with results from sera of 129 patients with candidemia from a different hospital.

RESULTS

Sensitivity of BDG testing (47%) was higher than for Ag (17%) or Ab (20%). By combining Ag and Ab testing, sensitivity was raised to 32%. Lowering the cut-off of BDG from 11 pg/ml to the newly recommended cut-off of 7 pg/ml resulted in a significant increase in sensitivity (47% vs. 58%, p=0.01 and 63 % vs. 71% p<0.01). At both centers, the increase was significant in NAC but not in C. albicans candidemia. No significant effects on specificity where observed.

CONCLUSION

BDG-testing outperformed Ag and Ab testing and its combination. Lowering the BDG cut-off had no significant impact on specificity. The increase in sensitivity can be mainly attributed to a gain in sensitivity for non-albicans Candida species blood stream infections.

Native Valve Candida metapsilosis Endocarditis Following a Ruptured Appendix: A Case Report

Candida parapsilosis complex has been further divided into C. parapsilosis, C. orthopsilosis, and C. metapsilosis. C. metapsilosis is considered to be the least virulent fungi of the complex. Candida endocarditis is uncommon but is associated with a very high mortality rate. Prosthetic or previously damaged valves act as common targets, but native, structurally normal valves are seldom affected. 

We hereby present a case of Candida metapsilosis endocarditis involving a native aortic valve in an immunocompetent 55-year-old male who was successfully treated with surgical valve replacement and antifungal therapy. 

Candidemia: Evolution of Drug Resistance and Novel Therapeutic Approaches

Candidemia and invasive candidiasis are the most common healthcare-associated invasive fungal infections, with a crude mortality rate of 25–50%. Candida albicans remains the most frequent etiology, followed by C. glabrata, C. parapsilosis and C. tropicalis. With the exception of a limited number of species (ie: C. krusei, C. glabrata and rare Candida species), resistance to fluconazole and other triazoles are quite uncommon. However, recently fluconazole-resistant C. parapsilosis, echinocandin-resistant C. glabrata and the multidrug resistant C. auris have emerged. Resistance to amphotericin B is even more rare due to the reduced fitness of resistant isolates. The mechanisms of antifungal resistance in Candida (altered drug-target interactions, reduced cellular drug concentrations, and physical barriers associated with biofilms) are analyzed. The choice of the antifungal therapy for candidemia must take into account several factors such as type of patient, presence of devices, severity of illness, recent exposure to antifungals, local epidemiology, organs involvement, and Candida species. The first-line therapy in non-neutropenic critical patient is an echinocandin switching to fluconazole in clinically stable patients with negative blood cultures and azole susceptible isolate. Similarly, an echinocandin is the drug of choice also in neutropenic patients. The treatment duration is 14 days after the first negative blood culture or longer in cases of organ involvement. An early removal of vascular catheter improves the outcome. The promising results of new antifungal molecules, such as the terpenoid derivative ibrexafungerp, the novel echinocandin with an enhanced half-life rezafungin, oteseconazole and fosmanogepix, representative of new classes of antifungals, are discussed.

Fungal Infections Other Than Invasive Aspergillosis in COVID-19 Patients

Invasive fungal disease (IFD) associated with Coronavirus Disease 2019 (COVID-19) has focussed predominantly on invasive pulmonary aspergillosis. However, increasingly emergent are non-Aspergillus fungal infections including candidiasis, mucormycosis, pneumocystosis, cryptococcosis, and endemic mycoses. These infections are associated with poor outcomes, and their management is challenged by delayed diagnosis due to similarities of presentation to aspergillosis or to non-specific features in already critically ill patients. There has been a variability in the incidence of different IFDs often related to heterogeneity in patient populations, diagnostic protocols, and definitions used to classify IFD. Here, we summarise and address knowledge gaps related to the epidemiology, risks, diagnosis, and management of COVID-19-associated fungal infections other than aspergillosis.

Treatment of Candida urinary tract infections with micafungin in children

BACKGROUND

Candida urinary tract infections (UTIs) are common nosocomial infections among critically ill patients hospitalized in pediatric intensive care Units (PICU). We aimed to report outcomes of critically ill pediatric patients who received micafungin for hospital acquired Candida UTIs. We analyzed treatment success rates and success rates among different Candida species.

METHODS

This retrospective cohort study included patients who received micafungin for Candida UTI as first choice in our PICU between January 2017 and July 2018. Data, including demographic and clinical features, were retrospectively collected from medical files of the patients. Treatment efficacy was defined as resolution of clinical symptoms and a negative culture for Candida at day 14 after initiation of micafungin treatment.

RESULTS

Twenty-four pediatric patients (median age 5.72 years, range, 2 months-16 years) were included in the present study. Fourteen (58.3%) patients had urinary catheters at the time of Candida isolation. Resolution of symptoms and a negative culture at day 3 of micafungin treatment were achieved in 17 (70.8%) and 14 (58.3%) patients, respectively. Moreover, 19 (79.2%) patients had a normal urine analysis and negative culture 14 days after initiation of micafungin treatment. Treatment responses did not statistically differ between Candida species.

CONCLUSIONS

Micafungin is safe and efficacious in critically ill pediatric patients with Candida UTIs. Its efficacy in our pediatric population was as comparable to that observed in adult studies, therefore, it should be considered as an effective therapeutic option in Candida UTIs of critically ill pediatric patients.

Candida parapsilosis bloodstream infection in an immunocompromised host with discordant multiplex polymerase chain reaction and conventional blood culture results: a case report

Prompt treatment of candidemia, especially in immunocompromised hosts, is known to improve outcomes. We present a case of discordance among results of Gram stain, multiplex polymerase chain reaction (PCR)-based rapid diagnostic technology, and conventional cultures that subsequently resulted in delayed therapy and hospitalization. An immunocompromised patient presented to the outpatient oncology clinic with signs and symptoms of systemic infection. Blood cultures were obtained, and Gram stain showed gram-negative rods, while multiplex PCR results (BioFire® FilmArray® BCID 1) returned positive for both Enterobacter cloacae and Candida parapsilosis. Conventional cultures only grew E. cloacae. Because of the discordant results, the primary team elected to give ertapenem monotherapy and defer antifungal therapy. The patient’s symptoms progressed, and 11 days later, the patient was admitted with subsequent positive blood cultures for C. parapsilosis. The patient required a 9-day hospitalization due to complications associated with candidemia. This case highlights the value of understanding and interpretation of rapid diagnostics, shared decision-making in antimicrobial management of high-risk patients, and the important responsibility of antimicrobial stewardship teams across the continuum of care.

OUP accepted manuscript

Studies demonstrated the impact of the COVID-19 pandemic in the prevalence and susceptibility profiles of bacterial and fungal organisms. We analyzed 4821 invasive fungal isolates collected during 2018, 2019, and 2020 in 48 hospitals worldwide to evaluate the impact of this event in the occurrence and susceptibility rates of common fungal species. Isolates were tested using the CLSI broth microdilution method. While the percentage of total isolates that were C. glabrata (n = 710 isolates) or C. krusei (n = 112) slightly increased in 2020, the percentage for C. parapsilosis (n = 542), A. fumigatus (n = 416), and C. lusitaniae (n = 84) significantly decreased (P < .05). Fluconazole resistance in C. glabrata decreased from 5.8% in 2018–2019 to 2.0% in 2020, mainly due to fewer hospitals in the US having these isolates (5 vs. 1 hospital). Conversely, higher fluconazole-resistance rates were noted for C. parapsilosis (13.9 vs. 9.8%) and C. tropicalis (3.5 vs. 0.7%; P < .05) during 2020. Voriconazole resistance also increased for these species. Echinocandin resistance was unchanged among Candida spp. Voriconazole susceptibility rates in A. fumigatus were similar in these two periods (91.7% in 2018 and 2019 vs. 93.0% in 2020). Changes were also noticed in the organisms with smaller numbers of collected isolates. We observed variations in the occurrence of organisms submitted to a global surveillance and the susceptibility patterns for some organism-antifungal combinations. As the COVID-19 pandemic is still ongoing, the impact of this event must continue to be monitored to guide treatment of patients affected by bacterial and fungal infections.

Molecular characterisation of Candida auris isolates from immunocompromised patients in a tertiary-care hospital in Kuwait reveals a novel mutation in FKS1 conferring reduced susceptibility to echinocandins

BACKGROUND

Candida auris is an emerging, potentially multidrug-resistant pathogen that exhibits clade-specific resistance to fluconazole and also develops resistance to echinocandins and amphotericin B easily. This study analysed 49 C auris isolates for alterations in hotspot-1 and hotspot-2 of FKS1 for the detection of mutations conferring reduced susceptibility to echinocandins.

METHODS

C auris isolates (n = 49) obtained from 18 immunocompromised patients during June 2016-December 2018 were analysed. Antifungal susceptibility testing was performed by Etest and broth microdilution-based MICRONAUT-AM assay. Mutations in hotspot-1 and hotspot-2 regions of FKS1 were detected by PCR sequencing and fingerprinting of the isolates was done by short tandem repeat typing.

RESULTS

The patients had multiple comorbidities/risk factors for Candida spp. infection including cancer/leukaemia/lymphoma/myeloma (n = 16), arterial/central line (n = 17), urinary catheter (n = 17), mechanical ventilation (n = 14) and major surgery (n = 9) and received antifungal drugs as prophylaxis and/or empiric treatment. Seven patients developed C auris candidemia/breakthrough candidemia, nine patients had candiduria with/without candidemia and four patients developed surgical site/respiratory infection. Resistance to fluconazole and amphotericin B was detected in 44 and four isolates, respectively. Twelve C auris isolates from eight patients showed reduced susceptibility to echinocandins. Seven isolates contained hostspot-1 mutations and three isolates from a candidemia patient contained R1354H mutation in hotspot-2 of FKS1. Ten patients died, five were cured, two were lost to follow-up and treatment details for one patient were not available.

CONCLUSIONS

Our findings describe development of a novel mutation in FKS1 conferring reduced susceptibility to echinocandins in one patient during treatment and unfavourable clinical outcome for many C auris-infected patients.

Introduction to the updated Australasian consensus guidelines for the management of invasive fungal disease and use of antifungal agents in the haematology/oncology setting, 2021

This article introduces the fourth update of the Australian and New Zealand consensus guidelines for the management of invasive fungal disease and use of antifungal agents in the haematology/oncology setting. These guidelines are comprised of nine articles as presented in this special issue of the Internal Medicine Journal. This introductory chapter outlines the rationale for the current update and the steps taken to ensure implementability in local settings. Given that 7 years have passed since the previous iteration of these guidelines, pertinent contextual changes that impacted guideline content and recommendations are discussed, including the evolution of invasive fungal disease (IFD) definitions. We also outline our approach to guideline development, evidence grading, review and feedback. Highlights of the 2021 update are presented, including expanded scope to provide more detailed coverage of common and emerging fungi such as Aspergillus and Candida species, and emerging fungi, and a greater focus on the principles of antifungal stewardship. We also introduce an entirely new chapter dedicated to helping healthcare workers convey important concepts related to IFD, infection prevention and antifungal therapy, to patients.

Septic shock due to co-infection with Legionella pneumophila and Saprochaete clavata

Septic shock is the most dreaded presentation of an infection, carrying a reserved prognosis. Appropriate antimicrobial therapy is therefore the mainstay of treatment, alongside organ support as needed. Legionnaires' disease is mainly due to Legionella pneumophila serogroup 1 but it can be caused by other serogroups and species not detected by the urinary antigen test. Anti-tumour necrosis factor α therapy may increase the risk of invasive fungal infection, which carry a poor prognosis. We present a challenging case of a septic shock due to Legionella pneumophila and Saprochaete clavata infections, with a review of the two infections presented.

Antifungal susceptibility profile of invasive Candida glabrata isolates (2009-2020) from a tertiary care hospital laboratory in Pakistan

Introduction. Invasive infections with Candida glabrata are a global concern due to poor clinical outcomes and propensity to acquire resistance to antifungal agents. Hypothesis/Gap Statement. Monitoring emerging resistance and trends in Candida glabrata, an important agent of candidemia in Pakistan, is critical for patient management; data that is missing from Pakistan. Aim. Thus, this study evaluated antifungal resistance and MICs) distribution in invasive C. glabrata isolates from Pakistan. Methods. This cross-sectional and retrospective study was conducted from January 2009 to March 2020 at a clinical laboratory in Pakistan that has a nation-wide network. Antifungal susceptibility data of 277 candidemia, deep organ and soft tissue (invasive) C. glabrata sensu lato isolates against fluconazole, itraconazole, voriconazole, posaconazole, anidulafungin, micafungin, caspofungin and amphotericin B was retrieved. Susceptibility testing was performed using colorimetric broth microdilution and interpreted using CLSI criteria. Demographics, clinical history and outcome were studied. Chi-square test was used to demonstrate association between antifungal resistance and clinical characteristics of the patients. Results. We identified 277 patients with invasive C. glabrata infection. Of which 48 (18.4%) isolates were resistant to fluconazole (MIC ≥64 mg l^-1), one isolate each was resistant to amphotericin (MIC=2 mg l^-1), anidulafungin (MIC=1 mg l^-1) and micafungin (MIC=0.5 mg l^-1). MIC₉₀ for fluconazole was 64 mg l^-1 and other triazoles 2 mg l^-1, caspofungin 0.12 mg l^-1, anidulafungin 0.06 mg l^-1, micafungin 0.03 mg l^-1 and amphotericin 0.5 mg l^-1. Fluconazole MIC ≥64 mg l^-1, caspofungin MIC >0.06 mg l^-1 and amphotericin MIC >0.25 mg l^-1 (above MIC₅₀) were significantly associated with patient being alive at the time of reporting, no use of healthcare devices, nor infection with other fungi. Fluconazole resistance was significantly associated with prior antifungal use by the patient. Conclusion. Surveillance data of antifungal resistance among common Candida species should be monitored closely for identification of resistant strains.

Revisiting oral thrush in South-East Asian patients: A review of published studies (2000-2020)

BACKGROUND

Oral thrush, a clinical condition due to an overgrowth of Candida yeasts in the oral cavity, is prominent in patients with immunosuppression. As recent updates on oral thrush in South-East Asian (SEA) countries are lacking, this review aimed to address the epidemiology, clinical features and distribution of Candida species, based on published studies in SEA countries over the last two decades.

METHODS

Published studies on oral candidiasis (2000-2020) were retrieved from PubMed, Scopus, ISI Web of Science and Google Scholar databases to provide information on the incidence and factors affecting oral thrush cases in SEA countries.

RESULTS

A total of 22 cross-sectional studies involving 3697 subjects from five SEA countries were reviewed in this study. The most frequently reported population were human immunodeficiency virus (HIV)-infected patients. The overall incidence rates amongst HIV-infected patients ranged from 20.7% to 97.0%, while incidence rates ranging from 0% to 72.7% were recorded for non-HIV-infected populations. Pseudomembranous candidiasis and erythematous candidiasis were the most common clinical presentations of oral thrush lesions. Candida albicans was the most common species identified in SEA studies. As oral thrush assessments were made merely based on clinical diagnosis, culture results were not available for most studies.

CONCLUSION

This review highlights that most studies reporting on oral candidiasis in SEA countries were based on HIV-positive patients. Data are still lacking on oral candidiasis amongst non-HIV immunocompromised and immunocompetent patients. Increasing awareness on the diagnosis, treatment and consequences of this infection, and improved laboratory methods are essential for the management of oral candidiasis in this region.

Critically ill patients with severe infections related to Geotrichum species: A French retrospective multicentre study

OBJECTIVES

Geotrichum spp can be responsible for severe infections in immunocompromised patients. We aim to describe Geotrichum-related infections in the ICU and to assess risk factors of mortality.

METHODS

Retrospective multicentre study, conducted in 14 French ICUs between 2002 and 2018, including critically ill adult patients with proven or probable infection related to Geotrichum species. Data were obtained from the medical charts.

RESULTS

Thirty-six patients, median age 60 years IQR [53; 66] were included. Most of the patients had haematological malignancies (78%). The reason for ICU admission was shock in half of the patients (n = 19, 53%) and respiratory failure in thirteen patients (36%). Median SOFA score was 8.5 IQR [7; 15]. Time between ICU admission and fungal diagnosis was 2.5 days [-1; 4]. Infection was disseminated in 27 (75%) patients with positive blood cultures in 25 patients (69%). Thirty patients (83%) received curative antifungal treatment in the ICU, in a median time of 1 day [0;1] after ICU admission. Twenty-four patients (67%) died in the ICU and hospital mortality rate was 69%. The number and extent of organ failures, as represented by SOFA score, were associated with mortality.

CONCLUSIONS

This study demonstrates poor outcome in critically ill patients with Geotrichum-related infections, which encourages a high level of suspicion.

Coronavirus Disease 2019-Associated Invasive Fungal Infection

Coronavirus disease 2019 (COVID-19) can become complicated by secondary invasive fungal infections (IFIs), stemming primarily from severe lung damage and immunologic deficits associated with the virus or immunomodulatory therapy. Other risk factors include poorly controlled diabetes, structural lung disease and/or other comorbidities, and fungal colonization. Opportunistic IFI following severe respiratory viral illness has been increasingly recognized, most notably with severe influenza. There have been many reports of fungal infections associated with COVID-19, initially predominated by pulmonary aspergillosis, but with recent emergence of mucormycosis, candidiasis, and endemic mycoses. These infections can be challenging to diagnose and are associated with poor outcomes. The reported incidence of IFI has varied, often related to heterogeneity in patient populations, surveillance protocols, and definitions used for classification of fungal infections. Herein, we review IFI complicating COVID-19 and address knowledge gaps related to epidemiology, diagnosis, and management of COVID-19-associated fungal infections.

Invasive fungal infections in acute and chronic liver impairment: A systematic review

Patients with acute and chronic liver impairment are susceptible to invasive fungal infections such as candidemia and invasive pulmonary aspergillosis as a result of cirrhosis-associated immune dysfunction, humoral immunodeficiency, cell-mediated dysfunction and systemic inflammation. Besides classical risk factors for invasive fungal infection, acute-on-chronic liver failure, corticosteroid use, gastrointestinal bleeding, and prophylactic use of antibiotics are all additional conditions which are related to the potential development of fungal infections. Therefore, high-risk patients should be carefully followed by microbiological surveillance including cultures but also by imaging and fungal biomarkers for providing early diagnosis. Echinocandins are still the mainstay and first line antifungal therapy in cases of invasive candidiasis. Due to concerns of liver toxicity and in cases of renal impairment liposomal amphotericin B is a suitable alternative to voriconazole in patients with invasive pulmonary aspergillosis. Although, data of isavucoanzole and posaconazole use in those patients are also promising more specific studies in the subgroup of patients with liver impairment are needed. Especially, due to the late diagnosis and multiple organ dysfunction usually present in patients with liver impairment morbidity and mortality rates remain high. Based on the broad spectrum of diverse reports with varying content and quality and in some cases lack of evidence we performed a systematic review on this topic.

Inflammasome-mediated GSDMD activation facilitates escape of Candida albicans from macrophages

Candida albicans is the most common cause of fungal sepsis. Inhibition of inflammasome activity confers resistance to polymicrobial and LPS-induced sepsis; however, inflammasome signaling appears to protect against C. albicans infection, so inflammasome inhibitors are not clinically useful for candidiasis. Here we show disruption of GSDMD, a known inflammasome target and key pyroptotic cell death mediator, paradoxically alleviates candidiasis, improving outcomes and survival of Candida-infected mice. Mechanistically, C. albicans hijacked the canonical inflammasome-GSDMD axis-mediated pyroptosis to promote their escape from macrophages, deploying hyphae and candidalysin, a pore-forming toxin expressed by hyphae. GSDMD inhibition alleviated candidiasis by preventing C. albicans escape from macrophages while maintaining inflammasome-dependent but GSDMD-independent IL-1β production for anti-fungal host defenses. This study demonstrates key functions for GSDMD in Candida's escape from host immunity in vitro and in vivo and suggests that GSDMD may be a potential therapeutic target in C. albicans-induced sepsis.

Indian Society of Pediatric Neurosurgery Consensus Guidelines on Preventing and Managing Shunt Infection: Version 2020-21

Background

Shunt infection is the most significant morbidity associated with shunt surgery. Based on the existing literature for the prevention and management of shunt infection, region and resource-specific recommendations are needed.

Methods

In February 2020, a Guidelines Development Group (GDG) was created by the Indian Society of Paediatric Neurosurgery (IndSPN) to formulate guidelines on shunt infections, which would be relevant to our country and LMIC in general. An initial email survey identified existing practices among the membership of the IndSPN, and eight broad issues pertaining to shunt infection were identified. Next, members of the GDG performed a systematic review of the literature on the prevention and management of shunt infection. Then, through a series of virtual meetings of the GDG over 1 year, evidence from the literature was presented to all the members and consensus was built on different aspects of shunt infection. Finally, the guidelines document was drafted and circulated among the GDG for final approval. Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to grade the evidence and strength of recommendation.

Results

The guidelines are divided into eight sections. Level I and Level II evidence was available for only five recommendations and led to a moderate level of recommendations. Most of the available evidence was at Level III and below, and hence the level of recommendation was low or very low. A consensus method was used to provide recommendations for several issues.

Conclusions

Although most of the recommendations for the prevention and management of shunt infections are based on a low level of evidence, we believe that this document will provide a useful reference to neurosurgeons not only in India but also in other low and middle income countries. These guidelines need to be updated as and when new evidence emerges.

Human plasma protein levels alter the in vitro antifungal activity of caspofungin: An explanation to the effect in critically ill?

BACKGROUND

Recent studies have shown low caspofungin concentrations in critically ill patients. In some patients, the therapeutic target, area under the total plasma concentration curve in relation to the minimal inhibition concentration (AUC_tot /MIC), seems not to be achieved and therapeutic drug monitoring (TDM) has been proposed. Caspofungin is highly protein-bound and the effect of reduced plasma protein levels on pharmacodynamics has not been investigated.

OBJECTIVES

Fungal killing activity of caspofungin in vitro was investigated under varying levels of human plasma protein.

METHODS

Time-kill studies were performed with clinically relevant caspofungin concentrations of 1-9 mg/L on four blood isolates of C. glabrata, three susceptible and one strain with reduced susceptibility, in human plasma and plasma diluted to 50% and 25% using Ringer's acetate.

RESULTS

Enhanced fungal killing of the three susceptible strains was observed in plasma with lower protein content (p < .001). AUC_tot /MIC required for a 1 log₁₀ CFU/ml kill at 24 h in 50% and 25% plasma was reduced with 36 + 12 and 80 + 9%, respectively. The maximum effect was seen at total caspofungin concentrations of 4-9 × MIC. For the strain with reduced susceptibility, growth was significantly decreased at lower protein levels.

CONCLUSIONS

Reduced human plasma protein levels increase the antifungal activity of caspofungin in vitro, most likely by increasing the free concentration. Low plasma protein levels in critically ill patients with candidemia might explain a better response to caspofungin than expected from generally accepted target attainment and should be taken into consideration when assessing TDM based on total plasma concentrations.

Modified Pitt bacteremia score for predicting mortality in patients with candidaemia: A multicentre seven-year retrospective study conducted in Japan

BACKGROUND

Several severity indexes have been reported for critically ill patients. The Pitt bacteremia score (PBS) is commonly used to predict the risk of mortality in patients with bacteraemia.

OBJECTIVES

To develop a scoring system for predicting mortality in candidaemia patients.

METHODS

Medical records at five Japanese tertiary hospitals were reviewed. Factors associated with mortality were analysed using logistic regression modelling. The discriminatory power of scoring models was evaluated by assessing the area under the receiver operating characteristic curve (AUC), net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

RESULTS

In total, 422 candidaemia patients were included. Higher PBS, dialysis and retainment of central venous catheter were independent risk factors for all-cause 30-day mortality. However, among the five PBS components, fever was not associated with mortality; therefore, we developed a modified version of the PBS (mPBS) by replacing fever with dialysis. AUC for PBS and mPBS were 0.74 (95% confidence interval [CI]: 0.68-0.80) and 0.76 (95% CI: 0.71-0.82), respectively. The increase in predictive ability of mPBS for 30-day mortality was statistically significant as assessed by NRI (0.24, 95% CI: 0.01-0.46, p = .04) and IRI (0.04, 95% CI: 0.02-0.06, p = .0008). When patients were stratified by mPBS into low (scores 0-3), moderate (4-7) and high risk (≥8), there were significant differences among the survival curves (p < .0001, log-rank test), and 30-day mortality rates were 13.8% (40/290), 36.8% (28/76) and 69.4% (34/49), respectively.

CONCLUSIONS

mPBS can be a useful tool for predicting mortality in candidaemia patients.

Population pharmacokinetic model-guided optimization of intravenous voriconazole dosing regimens in critically ill patients with liver dysfunction

STUDY OBJECTIVES

This study aimed to establish a population pharmacokinetic (PPK) model of intravenous voriconazole (VRC) in critically ill patients with liver dysfunction and to explore the optimal dosing strategies in specific clinical scenarios for invasive fungal infections (IFIs) caused by common Aspergillus and Candida species.

DESIGN

Prospective pharmacokinetics study.

SETTING

The intensive care unit in a tertiary-care medical center.

PATIENTS

A total of 297 plasma VRC concentrations from 26 critically ill patients with liver dysfunction were included in the PPK analysis.

METHODS

Model-based simulations with therapeutic range of 2-6 mg/L as the plasma trough concentration (C_min ) target and the free area under the concentration-time curve from 0 to 24 h (ƒAUC₂₄ ) divided by the minimum inhibitory concentration (MIC) (ie, ƒAUC₂₄ /MIC) ≥25 as the effective target were performed to optimize VRC dosing regimens for Child-Pugh class A and B (CP-A/B) and Child-Pugh class C (CP-C) patients.

RESULTS

A two-compartment model with first-order elimination adequately described the data. Significant covariates in the final model were body weight on both central and peripheral distribution volume and Child-Pugh class on clearance. Intravenous VRC loading dose of 5 mg/kg every 12 h (q12h) for the first day was adequate for CP-A/B and CP-C patients to attain the C_min target at 24 h. The maintenance dose regimens of 100 mg q12h or 200 mg q24h for CP-A/B patients and 50 mg q12h or 100 mg q24h for CP-C patients could obtain the probability of effective target attainment of >90% at an MIC ≤0.5 mg/L and achieve the cumulative fraction of response of >90% against C. albicans, C. parapsilosis, C. glabrata, C. krusei, A. fumigatus, and A. flavus. Additionally, the daily VRC doses could be increased by 50 mg for CP-A/B and CP-C patients at an MIC of 1 mg/L, with plasma C_min monitored closely to avoid serious adverse events. It is recommended that an appropriate alternative antifungal agent or a combination therapy could be adopted when an MIC ≥2 mg/L is reported, or when the infection is caused by C. tropicalis but the MIC value is not available.

CONCLUSIONS

For critically ill patients with liver dysfunction, the loading dose of intravenous VRC should be reduced to 5 mg/kg q12h. Additionally, based on the types of fungal pathogens and their susceptibility to VRC, the adjusted maintenance dose regimens with lower doses or longer dosing intervals should be considered for CP-A/B and CP-C patients.

Timing of antibiotic therapy in the ICU

Severe or life threatening infections are common among patients in the intensive care unit (ICU). Most infections in the ICU are bacterial or fungal in origin and require antimicrobial therapy for clinical resolution. Antibiotics are the cornerstone of therapy for infected critically ill patients. However, antibiotics are often not optimally administered resulting in less favorable patient outcomes including greater mortality. The timing of antibiotics in patients with life threatening infections including sepsis and septic shock is now recognized as one of the most important determinants of survival for this population. Individuals who have a delay in the administration of antibiotic therapy for serious infections can have a doubling or more in their mortality. Additionally, the timing of an appropriate antibiotic regimen, one that is active against the offending pathogens based on in vitro susceptibility, also influences survival. Thus not only is early empiric antibiotic administration important but the selection of those agents is crucial as well. The duration of antibiotic infusions, especially for β-lactams, can also influence antibiotic efficacy by increasing antimicrobial drug exposure for the offending pathogen. However, due to mounting antibiotic resistance, aggressive antimicrobial de-escalation based on microbiology results is necessary to counterbalance the pressures of early broad-spectrum antibiotic therapy. In this review, we examine time related variables impacting antibiotic optimization as it relates to the treatment of life threatening infections in the ICU. In addition to highlighting the importance of antibiotic timing in the ICU we hope to provide an approach to antimicrobials that also minimizes the unnecessary use of these agents. Such approaches will increasingly be linked to advances in molecular microbiology testing and artificial intelligence/machine learning. Such advances should help identify patients needing empiric antibiotic therapy at an earlier time point as well as the specific antibiotics required in order to avoid unnecessary administration of broad-spectrum antibiotics.

Nephrotoxicity of continuous amphotericin B in critically ill patients with abdominal sepsis: a retrospective analysis with propensity score matching

BACKGROUND

Continuous infusion of conventional amphotericin B (CCAB) is used in ICUs for pre-emptive treatment of invasive fungal infections. Amphotericin B has previously been associated with nephrotoxicity.

OBJECTIVES

To investigate if CCAB with therapeutic drug monitoring (TDM) results in renal impairment over time in critically ill patients with abdominal sepsis.

PATIENTS AND METHODS

The study was conducted at mixed medical-surgical ICUs of two large teaching hospitals in the Netherlands. Consecutive patients who were treated on the ICUs between 2006 and 2019 for abdominal sepsis, with or without CCAB, were included. CCAB dosing was guided by TDM. Serum creatinine concentrations and renal failure scores of patients with CCAB treatment were compared with those without CCAB treatment. Excluded were: (i) patients treated with CCAB for less than 72 h; and (ii) patients with renal replacement therapy.

RESULTS

A total of 319 patients were included (185 treated with CCAB and 134 controls). A multiple linear regression model showed that the serum creatinine concentration was independent of CCAB treatment (β = -0.023; 95% CI = -12.2 to 7.2; P = 0.615). Propensity score matching resulted in 134 pairs of CCAB-treated and non-treated patients. Again, the analysis of these pairs showed that the cumulative CCAB dose was not associated with serum creatinine concentration during intensive care treatment (β = 0.299; 95% CI = -0.38 to 0.98; P = 0.388).

CONCLUSIONS

CCAB with TDM did not result in renal impairment over time in critically ill patients with abdominal sepsis.

Effect of first-line antifungal treatment on ocular complication risk in Candida or yeast blood stream infection

Objectives

Ocular candidiasis (OC) can complicate Candida bloodstream infection (BSI). Antifungal treatment improves the prognosis of patients with BSI, but the effects of choice and timing of first-line medication on OC risk are incompletely understood. We explored the early treatments, risk factors and ocular presentations in Candida BSI.

Methods and analysis

All patients (n=304) with Candida BSI during 2008–2017 at Oulu University Hospital were included. Those patients in whom clinical condition was appropriate for ocular examination (OE), including biomicroscopy (n=103), were carefully analysed by ophthalmologists. Criteria for patient selection were considered. Candida and yeast species, antifungal medications, echocardiography, underlying diseases and clinical properties of the patients with Candida BSI were analysed.

Results

Clinical condition in 103 patients had been considered appropriate for OE. OC was diagnosed in 33 of the 103 patients. Candida albicans was the most common finding (88%) in OC. Patients in intensive care, alcohol-related conditions or poor prognosis were less frequently examined. Persistent candidemia increased the risk of OC. Chorioretinitis and endophthalmitis were diagnosed in 94% and 48% of the patients with OC, respectively. Any early antifungal treatment decreased the endophthalmitis risk. Echinocandin lowered the OC risk in those with central venous catheters (CVCs) or abdominal malignancy.

Conclusion

Critical condition of patients with Candida BSI affects the selection and results of OE. OC was associated with C. albicans BSI especially among those with persistent candidemia, CVC or abdominal malignancy. Any early antifungal treatment reduced endophthalmitis risk. Early echinocandin treatment may reduce the risk of OC in selected patients.

In vitro activity of ibrexafungerp against Candida species isolated from blood cultures. Determination of wild-type populations using the EUCAST method

OBJECTIVES

Ibrexafungerp is a new oral glucan synthase inhibitor with in vivo and in vitro activity against Candida spp., including echinocandin- and azole-resistant isolates. We studied the in vitro activity of ibrexafungerp against Candida species isolated from blood cultures and assessed wild-type upper limits against the five Candida species most frequently associated to candidaemia.

METHODS

Isolates (n = 958) causing incident episodes of candidaemia in patients admitted to Gregorio Marañón hospital (Madrid, Spain) between January 2007 and April 2021 were studied. Antifungal susceptibility to ibrexafungerp, fluconazole, micafungin and anidulafungin was tested (EUCAST E.Def 7.3.2) and wild-type upper limits determined against C. albicans (n = 462), C. glabrata (n = 120), C. parapsilosis (n = 249), C. tropicalis (n = 73) and C. krusei (n = 24). fksgene sequencing was carried out in non-wild-type isolates.

RESULTS

Ibrexafungerp showed antifungal in vitro activity against the studied isolates. Wild-type upper limits for ibrexafungerp were >0.25 mg/L against C. albicans, >1 mg/L against C. parapsilosis, C. glabrata, and C. tropicalis, and >2 mg/L against C. krusei. Percentages of ibrexafungerp non-wild-type isolates were low (C. parapsilosis and C. krusei, 0%; C. albicans, 0.22% (1/462); C. glabrata, 0.83% (1/120); and C. tropicalis, 1.37% (1/73)). Ibrexafungerp proved in vitro activity against fluconazole- or echinocandin-resistant isolates.

DISCUSSION

We show in vitro activity of ibrexafungerp against the tested Candida species. Furthermore, we provide ibrexafungerp wild-type upper limits, which allows defining the wild-type populations of the five most relevant Candida species.

The SAGA and NuA4 component Tra1 regulates Candida albicans drug resistance and pathogenesis

Candida albicans is the most common cause of death from fungal infections. The emergence of resistant strains reducing the efficacy of first-line therapy with echinocandins, such as caspofungin calls for the identification of alternative therapeutic strategies. Tra1 is an essential component of the SAGA and NuA4 transcriptional co-activator complexes. As a PIKK family member, Tra1 is characterized by a C-terminal phosphoinositide 3-kinase domain. In Saccharomyces cerevisiae, the assembly and function of SAGA and NuA4 are compromised by a Tra1 variant (Tra1Q3) with three arginine residues in the putative ATP-binding cleft changed to glutamine. Whole transcriptome analysis of the S. cerevisiae tra1Q3 strain highlights Tra1's role in global transcription, stress response, and cell wall integrity. As a result, tra1Q3 increases susceptibility to multiple stressors, including caspofungin. Moreover, the same tra1Q3 allele in the pathogenic yeast C. albicans causes similar phenotypes, suggesting that Tra1 broadly mediates the antifungal response across yeast species. Transcriptional profiling in C. albicans identified 68 genes that were differentially expressed when the tra1Q3 strain was treated with caspofungin, as compared to gene expression changes induced by either tra1Q3 or caspofungin alone. Included in this set were genes involved in cell wall maintenance, adhesion, and filamentous growth. Indeed, the tra1Q3 allele reduces filamentation and other pathogenesis traits in C. albicans. Thus, Tra1 emerges as a promising therapeutic target for fungal infections.

Increasing morbidity and mortality of candidemia over one decade in a Swiss university hospital

Background

The epidemiology of candidemia is evolving with raising concern about the emergence of intrinsically resistant non‐albicans Candida species and acquisition of antifungal resistance. In addition to microbiological surveys, epidemiological studies including clinical data are needed to assess the impact of candidemia on morbidity and mortality.

Objectives

To assess the clinical and microbiological trends of candidemia in a Swiss university hospital.

Patients/Methods.

This single‐centre retrospective study compared the incidence of candidemia, Candida species distribution, antifungal resistance profiles, clinical characteristics and outcomes between two periods separated by one decade.

Results

A total of 170 candidemic episodes were included (68 from period 1, 2004‐2006, and 102 from period 2, 2014‐2017). Incidence of candidemia (0.85 to 0.97 episode/10,000 patient‐days), species distribution (55%–57% C albicans) and antifungal susceptibilities remained unchanged. During period 2, candidemia was more frequently observed in intensive care units (ICU, 38% vs 19% in period 1, P = .01) and amongst older patients (median age 68 vs 59 years old, P < .01) with more immunosuppressive conditions (24% vs 9%, P = .01). Candidemia in period 2 was more frequently followed by septic shock (23% vs 7% in period 1, P = .01) and ICU admission (42% vs 12%, P < .01) and was associated with higher mortality (34% vs 18%, P = .03). Overall, factors associated with mortality in multivariate analyses included cirrhosis, solid malignancies and ICU stay at the time of candidemia.

Conclusions

Despite stable incidence, species distribution and antifungal resistance of candidemia, an epidemiological shift of the disease towards older and more critically ill patients was observed, with higher mortality rates.

Inhibitory effect of polyunsaturated fatty acids alone or in combination with fluconazole on Candida krusei biofilms in vitro and in Caenorhabditis elegans

The incidence of infections by non-albicans Candida species, including Candida krusei, is increasing. Candida krusei exhibits intrinsic resistance to fluconazole and rapidly develops acquired resistance to other antifungals. Moreover, this yeast can form biofilm with increased resistance. Hence, there is a need to develop novel therapeutic strategies to combat infections caused by this pathogen. One such approach is through combination therapy with natural compounds, such as polyunsaturated fatty acids (PUFAs). This study aims to investigate the effect of PUFAs on fluconazole susceptibility of C. krusei biofilms, as well as the conserved nature of these effects in the Caenorhabditis elegans infection model. C. krusei biofilms were exposed to various fatty acids as well as combinations of fluconazole and linoleic acid (LA) or gamma-linolenic acid (GLA). The effect of these treatments on biofilm formation, cell ultrastructure, membrane integrity, oxidative stress and efflux pump activity was evaluated. In addition, the ability of the PUFAs to prolong survival and reduce the fungal burden of infected C. elegans, in the absence and presence of fluconazole, was assessed. Two P|UFAs, LA and GLA had he displayed significant inhibition of C. krusei biofilms and both of them increased the susceptibility of C. krusei biofilm to fluconazole in vitro via induction of oxidative stress, cell membrane damage, and disruption of efflux pump activity. These PUFAs also extended the lifespan of infected nematodes and displayed a potentiating effect with fluconazole in this model. This may pave the way for future studies into novel antifungal drug targets and treatment options.

LAY ABSTRACT

The pathogenic yeast, Candida krusei, is naturally resistant to the antifungal drug, fluconazole. This study finds that polyunsaturated fatty acids, linoleic and gamma-linolenic acid, can inhibit C. krusei and overcome this resistance of in vitro biofilms, as well as in a nematode infection model.

Malignant Transformation and Treatment Recommendations of Chronic Hyperplastic Candidiasis-A Six-year Retrospective Cohort Study

BACKGROUND

Oral chronic hyperplastic candidiasis (CHC) is the most uncommon type of oral candidiasis with diverse manifestations. Up to date the diagnosis, long-term management and prognosis of this oral potentially malignant disorder remain obscure.

OBJECTIVES

The aim of this study was to provide the recommendations guiding the diagnostic procedure, clinical management and prognosis assessment of CHC.

METHODS

A retrospective cohort study was performed during January 2015 to April 2021 involving patients with a definite diagnosis of CHC in the Department of Oral Medicine of Peking University School and Hospital of Stomatology. Demographic features, clinical and histopathological features, treatment protocols and follow-ups including malignancy transformation were analysed.

RESULTS

Fourty eight CHC patients were collected and reviewed, with a male-to-female ratio of 2.69:1. The average age at diagnosis was 54.92 ± 9.79 (36-80) years old. Clinically, the multiform oral lesions were diverse and frequently presented as white plaque and erythematous lesions. As a result, the initial diagnostic accordance rate was only 54.17%, and the most common presumptive initial diagnoses were oral lichen planus (22.92%), oral leukoplakia (20.83%) and traumatic lesion (2.08%). Histopathologically, ten (20.83%) patients had varying degrees of epithelial dysplasia, and two (4.17%) patients had malignant transformation with a mean transformation time of 6.5 ± 6.36 months. Among the 28 patients who underwent fungal culture, 24 patients were exclusively infected by Candida albicans, with two patients each mixed infected by C glabrata and C tropicalis, respectively. Notably, treatment with fluconazole had the lower recurrence rate compared with topical nystatin.

CONCLUSIONS

The diagnosis and management of CHC remain a challenge due to its polymorphic clinical presentations, chronic progression and potential of malignant transformation.

Predicting a therapeutic cut-off serum level of itraconazole in recalcitrant tinea corporis and cruris-A prospective trial

BACKGROUND

With rising resistance to terbinafine, and consistently high MICs to fluconazole and griseofulvin, itraconazole is being increasingly used as a first line drug for tinea corporis/cruris. However, inadequate clinical responses are often seen with it in spite of in vitro susceptibility. This is possibly related to a variable pharmacokinetic profile of itraconazole. The drug serum levels associated with the therapeutic outcome have not been defined in dermatophytic infections.

METHODS

Forty treatment naïve patients with tinea corporis/cruris were randomised to one of the three dose groups (100, 200 and 400 mg/day) of itraconazole. The drug serum levels of 21 of these patients were obtained after 2 weeks of treatment and correlated with the final clinical outcome and in vitro antifungal susceptibility data.

RESULTS

Trichophyton indotineae was identified by sequencing of ITS region of rDNA and TEF1α. All isolates were sensitive to itraconazole (Minimum Inhibitory Concentration (MICs) range: 0.06-0.5 µg/ml), while MICs to terbinafine were uniformly high (range 8-32 µg/ml). Thirty-seven patients (92.5%) achieved complete cure, while three failed treatment. Serum levels achieved with 400 mg/day were significantly higher than levels with 100 or 200 mg dose. All patients with itraconazole serum levels of >0.2 µg/ml were cured, while two out of the 10 patients with serum levels <0.2 µg/ml failed treatment.

CONCLUSIONS

Therapeutic failures are uncommon with itraconazole, and the prevalent strain in India has low itraconazole MICs. Treatment failure is likely with itraconazole serum levels of <0.2 µg/ml, while levels >0.2 µg/ml are consistently associated with a positive therapeutic outcome.

Candida fracture-related infection: a systematic review

Background: The aim of this study is to summarize and improve knowledge regarding a Candida fracture-related infection (CFRI) through a systematic review on the topic, accompanied by a case report. Methods: A systematic review and meta-analysis based on PRISMA statement were conducted on the CFRI topic. The following combined search terms were used to explore PubMed, Cochrane, and the Embase database: "fungal infection", "candida", "fracture related infection", "bone infection", "orthopedic infection", "internal fixation", "post-traumatic infection", and "osteomyelitis". Results: Out of 1514 records, only 5 case reports matched the selection criteria and were included. Moreover, a new case of CFRI, not previously described, was reported in this paper and reviewed. The main risk factors for CFRI were open wounds (three cases) and immunodeficiency (three cases). Initial improvement of clinical and laboratory signs of infection was noted in all cases. In the available short-term follow-up (mean 12.1 months; range 3-42), the reoperation rate was 33.3 %. Using a strategy based on extensive debridement/resection methods and prolonged systemic antifungal therapy (mean 8.8 weeks; range 6-18), four of six cases (66.6 %) were cured. Bone union occurred in three out of six cases. Conclusion: There is very low-quality evidence available regarding CFRI. Candida infections in surgically treated fractures are rare but difficult-to-treat events, with a slow onset, unspecific symptoms or signs, and a significant relapse risk; therefore, they still represent a current diagnostic challenge. The existing fracture-related infection treatment algorithm combined with long-term systemic antifungal therapy has an anecdotal value and needs more extensive studies to be validated.

Non-Candida Fungal Prosthetic Joint Infections

Background: Fungal prosthetic joint infections (PJIs) are rare, especially those caused by non-Candida species. Treatment has not been fully elucidated, since a plethora of antifungal and surgical interventions have been proposed. Τhis study represents an effort to clarify the optimal management of non-Candida fungal PJIs, by reviewing all relevant published cases. Methods: A thorough review of all existing non-Candida fungal PJIs in the literature was conducted. Data regarding demographics, responsible organisms, antifungal treatment (AFT), surgical intervention, time between initial arthroplasty and onset of symptoms, and time between onset of symptoms and firm diagnosis, as well as the infection’s outcome, were evaluated. Results: Forty-two PJIs, in patients with mean age of 66.2 years, were found and reviewed. Aspergillus spp. were isolated in most cases (10; 23.8%), followed by Coccidioides spp. (7; 16.7%) and Pichiaanomala (5; 11.9%). Fluconazole was the preferred antifungal regimen (20 cases; 47.6%), followed by amphotericin B (18 cases; 42.9%), while the mean AFT duration was 9.4 months (SD = 7.06). Two-stage revision arthroplasty (TSRA) was performed in 22 cases (52.4%), with the mean time between stages being 5.2 months (SD = 2.9). The mean time between initial joint implantation and onset of symptoms was 42.1 months (SD = 50.7), while the mean time between onset of symptoms and diagnosis was 5.8 months (SD = 14.3). Conclusions: Non-Candida fungal PJIs pose a clinical challenge, demanding a multidisciplinary approach. The present review has shown that combination of TSRA separated by a 3–6-month interval and prolonged AFT has been the standard of care in the studied cases.

Use and outcome of empiric echinocandins in critically ill patients

BACKGROUND

Echinocandins are recommended as a first-line empiric treatment for fungal infections of patients in an intensive care unit (ICU) with critical illness. The primary aim of the study was to compare outcomes among ICU patients treated with empiric anidulafungin (ANI), caspofungin (CASPO), or micafungin (MICA).

METHODS

A retrospective cohort study in a mixed adult ICU. Patient demographics, reason for ICU admission, ICU risk scores and organ support therapies were analyzed. Outcome parameters included ICU and hospital stay, 30-day mortality and 1-year mortality.

RESULTS

Empiric echinocandin therapy was given to 367 patients (ANI; 73 patients, CASPO; 84 patients, and MICA; 210 patients) with a median duration of 3 days in an ICU. Patient median age was 60.7 years. As a first-line therapy, 52% of patients received fluconazole. Positive Candida cultures were found in the following samples: blood, 16 (4.4%); central line, 27 (7.4%); deep site, 92 (25.1%). Median ICU stay (ANI 6.4 days, CASPO 5.3 days, MICA 8.1 days), hospital stay (ANI 33 days, CASPO 30 days, MICA 30 days), 30-day mortality (ANI 27%, CASPO 32%, MICA 32%), and 1-year mortality (ANI 33%, CASPO 44%, MICA 45%) did not differ between the groups . The cost of antifungal therapy during the ICU period was similar in the three echinocandin groups (ANI; €1 872, CASPO; €1 799, and MICA; €1783).

CONCLUSION

Our results show that ICU, hospital stay, and mortality (hospital, 30-day and 1-year) did not differ among patients with empiric anidulafungin, caspofungin, or micafungin treatment in a mixed adult ICU.

Update on Candida krusei, a potential multidrug-resistant pathogen

Although Candida albicans remains the main cause of candidiasis, in recent years a significant number of infections has been attributed to non-albicans Candida (NAC) species, including Candida krusei. This epidemiological change can be partly explained by the increased resistance of NAC species to antifungal drugs. C. krusei is a diploid, dimorphic ascomycetous yeast that inhabits the mucosal membrane of healthy individuals. However, this yeast can cause life-threatening infections in immunocompromised patients, with hematologic malignancy patients and those using prolonged azole prophylaxis being at higher risk. Fungal infections are usually treated with five major classes of antifungal agents which include azoles, echinocandins, polyenes, allylamines, and nucleoside analogues. Fluconazole, an azole, is the most commonly used antifungal drug due to its low host toxicity, high water solubility, and high bioavailability. However, C. krusei possesses intrinsic resistance to this drug while also rapidly developing acquired resistance to other antifungal drugs. The mechanisms of antifungal resistance of this yeast involve the alteration and overexpression of drug target, reduction in intracellular drug concentration and development of a bypass pathway. Antifungal resistance menace coupled with the paucity of the antifungal arsenal as well as challenges involved in antifungal drug development, partly due to the eukaryotic nature of both fungi and humans, have left researchers to exploit alternative therapies. Here we briefly review our current knowledge of the biology, pathophysiology and epidemiology of a potential multidrug-resistant fungal pathogen, C. krusei, while also discussing the mechanisms of drug resistance of Candida species and alternative therapeutic approaches.

Biomarkers for the diagnosis of invasive candidiasis in immunocompetent and immunocompromised patients

Blood culture methods show low sensitivity, so reliable non-culture diagnostic tests are needed to help clinicians with the introduction, de-escalation, and discontinuation of antifungal therapy in patients with suspected invasive candidiasis (IC). We evaluated different biomarkers for the diagnosis of IC in immunocompetent and immunocompromised patients at risk for developing invasive fungal diseases. The specificity of Candida albicans germ-tube antibodies (CAGTA) detection was high (89%-100%), but sensitivity did not exceed 61% even after raising the cut-off from 1/160 to 1/80. We developed enzyme-linked immunoassays detecting antibodies against C. albicans proteins (Als3-N, Hwp1-N, or Met6) that resulted more sensitive (66%-92%) but less specific than CAGTA assay. The combination of 1,3-beta-D-glucan (BDG) detection and CAGTA results provided the highest diagnostic usefulness in immunocompetent patients. However, in immunocompromised patients, anti-Met6 antibodies was the best biomarker, both, alone or in combination with BDG.

Dynamics and Predictors of Mortality Due to Candidemia Caused by Different Candida Species: Comparison of Intensive Care Unit-Associated Candidemia (ICUAC) and Non-ICUAC

We investigated mortality and predictors of mortality due to intensive care unit-associated candidemia (ICUAC) versus non-ICUAC by Candida species. This study included all candidemia cases in 11 hospitals from 2017 to 2018 in South Korea. The all-cause mortality rates in all 370 patients with ICUAC were approximately twofold higher than those in all 437 patients with non-ICUAC at 7 days (2.3-fold, 31.1%/13.3%), 30 days (1.9-fold, 49.5%/25.4%), and 90 days (1.9-fold, 57.8%/30.9%). Significant species-specific associations with 7- and 30-day ICUAC-associated mortality were not observed. Multivariate analysis revealed that ICU admission was an independent predictor of Candida glabrata (OR, 2.07–2.48) and Candida parapsilosis-associated mortality (OR, 6.06–11.54). Fluconazole resistance was a predictor of C. glabrata-associated mortality (OR, 2.80–5.14). Lack (less than 3 days) of antifungal therapy was the strongest predictor of 7-day mortality due to ICUAC caused by Candida albicans (OR, 18.33), Candida tropicalis (OR, 10.52), and C. glabrata (OR, 21.30) compared with 30- and 90-day mortality (OR, 2.72–6.90). C. glabrata ICUAC had a stronger association with lack of antifungal therapy (55.2%) than ICUAC caused by other species (30.6–36.7%, all p < 0.05). Most predictors of mortality associated with ICUAC were distinct from those associated with non-ICUAC and were mediated by Candida species.