Glabrata Infection Research Articles

Ophthalmologic Examination and Echocardiography Should be the Essential Components of Candidemia Bundle.

Candidemia is the most common form of invasive candidiasis, and it is associated with end-organ involvement, prolonged hospitalization, increased mortality, and higher healthcare costs. Candidemia can lead to metastatic heart and ocular infections. This study aimed to define the incidence, characteristics, and mortality of candidemia episodes and compare the data with our center's previous results. In this single-center retrospective observational study, we enrolled 250 patients over 18 years diagnosed with candidemia between January 2015 and December 2020. We obtained patients' demographic, clinical, laboratory, and therapeutic data from medical records. An ophthalmologic examination and screening with echocardiography were carried out within the first week after candidemia diagnosis. There were 275 candidemia episodes from 250 patients. The incidence of candidemia was 2.8/1000 admissions and 5.68/ 10,000 inpatient days, higher than our previous results (1.23/1000 and 3.29/10,000). The median age was 65 (interquartile range [IQR]=52-75) years. Malignancies were the most frequent comorbidity (50%). The most common type was Candida albicans (n=115, 41.8%). Candida glabrata (n=61, 22.2%) was common, particularly in surgical patients, patients with malignancy, and critically ill patients. There was Infectious disease consultation in 93.3% (257) episodes.The ophthalmoscopic examination was made in 145 episodes (52.7%), and ophthalmitis was detected in 16 (11.0%). Echocardiography was performed in 139 (50.5%) episodes; one case had an endocarditis diagnosis. The 30-day mortality was 44.7% (n=123). Mortality rates in C. glabrata and Candida krusei infections were higher (54.1% and 66.7). The factors related to mortality were intensive care unit requirement (p=0.0001), chronic liver disease (p=0.005), corticosteroid usage (p=0.0001), previous antibiotic usage (p=0.013), multiple antibiotic usage ( p=0.020), and CVC related candidemia (p=0.010). Because of the life-threatening complications such as endocarditis, increased mortality rates, and higher healthcare costs, systematic and comprehensive candidemia bundle applications would be effective strategies for providing an effective antifungal stewardship program.

Limosilactobacillus fermentum Limits Candida glabrata Growth by Ergosterol Depletion.

Candida glabrata is a human-associated opportunistic fungal pathogen. It shares its niche with Lactobacillus spp. in the gastrointestinal and vaginal tract. In fact, Lactobacillus species are thought to competitively prevent Candida overgrowth. We investigated the molecular aspects of this antifungal effect by analyzing the interaction of C. glabrata strains with Limosilactobacillus fermentum. From a collection of clinical C. glabrata isolates, we identified strains with different sensitivities to L. fermentum in coculture. We analyzed the variation of their expression pattern to isolate the specific response to L. fermentum. C. glabrata-L. fermentum coculture induced genes associated with ergosterol biosynthesis, weak acid stress, and drug/chemical stress. L. fermentum coculture depleted C. glabrata ergosterol. The reduction of ergosterol was dependent on the Lactobacillus species, even in coculture with different Candida species. We found a similar ergosterol-depleting effect with other lactobacillus strains (Lactobacillus crispatus and Lactobacillus rhamosus) on Candida albicans, Candida tropicalis, and Candida krusei. The addition of ergosterol improved C. glabrata growth in the coculture. Blocking ergosterol synthesis with fluconazole increased the susceptibility against L. fermentum, which was again mitigated by the addition of ergosterol. In accordance, a C. glabrata Δerg11 mutant, defective in ergosterol biosynthesis, was highly sensitive to L. fermentum. In conclusion, our analysis indicates an unexpected direct function of ergosterol for C. glabrata proliferation in coculture with L. fermentum. IMPORTANCE The yeast Candida glabrata, an opportunistic fungal pathogen, and the bacterium Limosilactobacillus fermentum both inhabit the human gastrointestinal and vaginal tract. Lactobacillus species, belonging to the healthy human microbiome, are thought to prevent C. glabrata infections. We investigated the antifungal effect of Limosilactobacillus fermentum on C. glabrata strains quantitively in vitro. The interaction between C. glabrata and L. fermentum evokes an upregulation of genes required for the synthesis of ergosterol, a sterol constituent of the fungal plasma membrane. We found a dramatic reduction of ergosterol in C. glabrata when it was exposed to L. fermentum. This effect extended to other Candida species and other Lactobacillus species. Furthermore, fungal growth was efficiently suppressed by a combination of L. fermentum and fluconazole, an antifungal drug which inhibits ergosterol synthesis. Thus, fungal ergosterol is a key metabolite for the suppression of C. glabrata by L. fermentum.

Epidemiology, management and outcome of candidaemia in patients with diabetes.

Candidaemia is the commonest fungal bloodstream infection in hospitalised patients. Diabetes is one of the risk factors for mortality from candidaemia. We compared the epidemiology, clinical characteristics and management of candidaemia in patients with and without diabetes. Over a 10-year period, 200 episodes of Candida bloodstream infection were documented. Patients with diabetes were younger (58.7 vs 65.5 years), less likely to be suffering from cancer (21.8% vs 36%), and had significantly lower 30-day and 90-day crude mortality (17.2% vs 35.6% and 28.4% vs 48.6%, respectively). Candida glabrata was more common in patients with diabetes (39.3% vs 29.7%). Based on European Confederation of Medical Mycology (ECMM) quality indicators, the management of patients with and without diabetes was similar. Our study highlights the importance of epidemiological data in relation to candidaemia in patients with diabetes and the growing threat of invasive C. glabrata infection in this subset of patients.

Recombinant polymerase amplification combined with lateral flow strips for the detection of deep-seated Candida krusei infections

The incidence of Candida infections in intensive care units (ICU) has significantly increased in recent years, and these infections have become one of the most serious complications threatening the lives of ICU patients. The proportion of non-Candida albicans infections, such as Candida krusei and Candida glabrata infections, which are resistant to fluconazole, is increasing each year. Early identification of the strains causing Candida infections is important for the timely implementation of targeted treatments to save patients’ lives. However, the current methods of direct microscopy, culture, and histopathology, as well as other diagnostic methods, have many shortcomings, such as their low sensitivity and long assay times; therefore, they cannot meet the needs for early clinical diagnosis. Recombinant polymerase amplification (RPA) is a promising isothermal amplification technique that can be performed without sophisticated instruments and equipment, and is suitable for use in resource-poor areas. RPA combined with lateral flow strips (LFS) can be used to rapidly amplify and visualize target genes within 20 min. In this study, RPA-LFS was used to amplify the internal transcribed spacer 2 (ITS2) region of C. krusei. The primer-probe design was optimized by introduction of base mismatches (probe modification of five bases) to obtain a specific and sensitive primer-probe combination for the detection of clinical specimens. Thirty-five common clinical pathogens were tested with RPA-LFS to determine the specificity of the detection system. The RPA-LFS system specifically detected C. krusei without cross-reaction with other fungi or bacteria. A gradient dilution of the template was tested to explore the lower limit of detection and sensitivity of the assay. The sensitivity was 10 CFU/50 µL per reaction, without interference from genomic DNA of other species. The RPA-LFS and qPCR assays were performed on 189 clinical specimens to evaluate the detection performance of the RPA-LFS system. Seventy-six specimens were identified as C. krusei, indicating a detection rate of 40.2%. The results were consistent with those of qPCR and conventional culture methods. The RPA-LFS system established in our study provides a reliable molecular diagnostic method for the detection of C. krusei, thus meeting the urgent need for rapid, specific, sensitive, and portable clinical field testing.

Establishment of a rapid diagnosis method for Candida glabrata based on the ITS2 gene using recombinase polymerase amplification combined with lateral flow strips.

Candida glabrata is the second or third most common Candida-associated species isolated from hospital-acquired infections, surpassing even C. albicans in some hospitals. With the rapid progression of the disease course of C. glabrata infections, there is an urgent need for a rapid and sensitive on-site assay for clinical diagnosis. Isothermal amplification is a recently developed method for rapid nucleic acid detection that is being increasingly used for on-site detection, especially recombinase polymerase amplification (RPA). RPA combined with lateral flow strips (LFS) can rapidly amplify and visually detect the target gene within 20 min. The whole detection process can be controlled within 30–60 min by rapid sample pre-treatment. In this study, RPA-LFS was used to amplify the internal transcribed spacer region 2 gene of C. glabrata. The primer–probe design was optimized by introducing base mismatches (probe modification of one base) to obtain a highly specific and sensitive primer–probe combination for clinical sample detection. RPA-LFS was performed on 23 common clinical pathogens to determine the specificity of the assay system. The RPA-LFS system specifically detected C. glabrata without cross-reaction with other fungi or bacteria. Gradient dilutions of the template were tested to explore the lower limit of detection of this detection system and to determine the sensitivity of the assay. The sensitivity was 10 CFU/µL, without interference from genomic DNA of other species. The RPA-LFS and qPCR assays were performed on 227 clinical samples to evaluate the detection performance of the RPA-LFS system. Eighty-five samples were identified as C. glabrata, representing a detection rate of 37.5%. The results were consistent with qPCR and conventional culture methods. The collective findings indicate a reliable molecular diagnostic method for the detection of C. glabrata, and to meet the urgent need for rapid, specific, sensitive, and portable clinical field-testing.

Nickel N‐heterocyclic carbene complexes based on xanthines: Synthesis and antifungal activity on Candida sp.

Invasive fungal diseases affect more than two million people worldwide. The increasing incidence of invasive fungal infections is the result of many factors, including an increase in the resistance to current drugs. As such, there is an urgent need to obtain new drugs that are efficient, selective, and able to overcome existing resistance mechanisms. Candida yeasts are responsible for more than 70% of all nosocomial invasive fungal diseases. In this work, we describe the synthesis of nickel (II)(NHC) complexes based on xanthines, by direct metalation of xanthinium salts with nickelocene NiCp2to yield [NiCpI(NHC)] complexes. For methyl caffeine, a biscarbene complex [NiCp(NHC)2]+is also formed, resulting from carbene dissociation from the corresponding monocarbene. [NiCpI(NHC)] complexes are active as antifungals for Candida yeasts and show toxicity for human cells (HeLa) that is dependent on the substitution of N7 of the xanthine moiety. The biscarbene complex 5[NiCp(NHC)2]+is highly selective for Candida glabrata and shows very low toxicity for human cells, being a promising candidate for selective treatment of C. glabrata infections.

Ent-hardwickiic acid from C. pubiflora and its microbial metabolites are more potent than fluconazole in vitro against Candida glabrata.

The incidence of Candida glabrata infections has rapidly grown and this species is among those responsible for causing invasive candidiasis with a high mortality rate. The diterpene ent-hardwickiic acid is a major constituent in Copaifera pubiflora oleoresin and the ethnopharmacological uses of this oleoresin by people from Brazilian Amazonian region point to a potential use of this major constituent as an antimicrobial. Therefore, the goal of this study was to evaluate the antifungal activity of ent-hardwickiic acid against Candida species and to produce derivatives of this diterpene by using microbial models for simulating the mammalian metabolism. The microbial transformations of ent-hardwickiic acid were carried out by Aspergillus brasiliensis and Cunninghamella elegans and hydroxylated metabolites were isolated and their chemical structures were determined. The antifungal activity of ent-hardwickiic acid and its metabolites was assessed by using the microdilution broth method in 96-well microplates and compared with that of fluconazole. All the diterpenes showed fungistatic effects (ranging from 19·7 to 75·2 µmol l-1 ) against C. glabrata at lower concentrations than fluconazole (163·2 µmol l-1 ) and were more potent fungicides (ranging from 39·5 to 150·4 µmol l-1 ) than fluconazole, which showed fungicidal effect at the concentration of 326·5 µmol l-1 .

Automated characterisation of neutrophil activation phenotypes in ex vivo human Candida blood infections

Rapid identification of pathogens is required for early diagnosis and treatment of life-threatening bloodstream infections in humans. This requirement is driving the current developments of molecular diagnostic tools identifying pathogens from human whole blood after successful isolation and cultivation. An alternative approach is to determine pathogen-specific signatures from human host immune cells that have been exposed to pathogens. We hypothesise that activated immune cells, such as neutrophils, may exhibit a characteristic behaviour — for instance in terms of their speed, dynamic cell morphology — that allows (i) identifying the type of pathogen indirectly and (ii) providing information on therapeutic efficacy. In this feasibility study, we propose a method for the quantitative assessment of static and morphodynamic features of neutrophils based on label-free time-lapse imaging data. We investigate neutrophil activation phenotypes after confrontation with fungal pathogens and isolation from a human whole-blood assay. In particular, we applied a machine learning supported approach to time-lapse microscopy data from different infection scenarios and were able to distinguish between Candida albicans and C. glabrata infection scenarios with test accuracies well above 75%, and to identify pathogen-free samples with accuracy reaching 100%. These results significantly exceed the test accuracies achieved using state-of-the-art deep neural networks to classify neutrophils by their morphodynamics.

Case Report: Echinocandin-Resistance Candida glabrata FKS Mutants From Patient Following Radical Cystoprostatectomy Due to Muscle-Invasive Bladder Cancer

Invasive Candida glabrata infections are not common complications after radical cystoprostatectomy. Furthermore, resistance to echinocandins arising during the course of a patient’s treatment is rarely recognised. We described a case of development of echinocandin resistance in a patient with muscle-invasive bladder cancer (pT2b N0 M0, high grade) diagnosis, subjected to radical cystoprostatectomy and exposed to echinocandins. A male patient with a previous surgical history after a traffic accident, who was operated on due to bladder cancer, underwent an episode of candidemia and mixed postoperative wound and urinary tract infection caused by C. glabrata and extended spectrum β-lactamase (ESBL)-producing Escherichia coli during hospital treatment. The patient was started on caspofungin. Repeat blood cultures showed clearance of the bloodstream infection; however, infection persisted at the surgical site. Resistance to echinocandins developed within 2 months from the day of initiation of therapy with caspofungin in the C. glabrata strain obtained from the surgical site. The isolates sequentially obtained during the patient’s treatment demonstrated resistance to echinocandins due to the mutation in hotspot 1 FKS2. Although resistance to echinocandins is relatively rare, it should be considered in oncological patients with increased complexity of treatment and intestinal surgery.

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.

Characterization of Awp14, A Novel Cluster III Adhesin Identified in a High Biofilm-Forming Candida glabrata Isolate.

Candida glabrata is among the most prevalent causes of candidiasis. Unlike Candida albicans, it is not capable of changing morphology between yeast and hyphal forms but instead has developed other virulence factors. An important feature is its unprecedented large repertoire of predicted cell wall adhesins, which are thought to enable adherence to a variety of surfaces under different conditions. Here, we analyzed the wall proteome of PEU1221, a high biofilm-forming clinical strain isolated from an infected central venous catheter, under biofilm-forming conditions. This isolate shows increased incorporation of putative adhesins, including eight proteins that were not detected in walls of reference strain ATCC 2001, and of which Epa22, Awp14, and Awp2e were identified for the first time. The proteomics data suggest that cluster III adhesin Awp14 is relatively abundant in PEU1221. Phenotypic studies with awp14Δ deletion mutants showed that Awp14 is not responsible for the high biofilm formation of PEU1221 onto polystyrene. However, awp14Δ mutant cells in PEU1221 background showed a slightly diminished binding to chitin and seemed to sediment slightly slower than the parental strain suggesting implication in fungal cell-cell interactions. By structural modeling, we further demonstrate similarity between the ligand-binding domains of cluster III adhesin Awp14 and those of cluster V and VI adhesins. In conclusion, our work confirms the increased incorporation of putative adhesins, such as Awp14, in high biofilm-forming isolates, and contributes to decipher the precise role of these proteins in the establishment of C. glabrata infections.

Pancreatic Pseudocyst with Candida glabrata Infection

The incidence of infection in pancreatic pseudocysts is estimated to be about 8.5%, commonly being bacterial. Fungal infection may occur and is usually secondary to intervention. We report here the case of a 51-year-old male with pancreatitis – not previously subjected to endoscopic, radiological, or surgical intervention – who presented with fever and mass and was found to have a pancreatic pseudocyst with Candida glabrata infection.

Micafungin Is an Efficient Treatment of Multi Drug-Resistant Candida glabrata Urosepsis: A Case Report

Candiduria is a common nosocomial infection in hospitalized patients, which may progress into life-threatening candidemia. Successful treatment of urosepsis requires early and effective antifungal therapy, while the available agents within three pharmacological classes each have characteristic pharmacokinetics and side effect profiles. Moreover, treatment of Candida spp. infections is becoming challenging due to increasing multi drug-resistance. Here, we present a case of candidemia resulting from a multi drug-resistant C. glabrata infection of the urinary tract. Due to resistance to fluconazole and a contraindication for amphotericin B, micafungin was used in the treatment, regardless of its unfavorable pharmacokinetic properties. Our study showed that despite the expected low levels in the urinary tract, micafungin was successful in the eradication of C. glabrata allowing full recovery of the patient. Thus, micafungin should be considered in the management of urosepsis caused by sensitive Candida spp.

Silver nanoparticles, a promising treatment against clinically important fluconazole-resistant Candida glabrata.

Resistance to azole antifungal agents is a challenging limitation in Candida glabrata treatment. It is associated with decreased intracellular concentrations of antifungal agents as a result of overexpression of efflux pumps on the cellular plasma membranes. This work evaluates the potential of silver nanoparticles (AgNPs) to reverse the resistance of fungal cells to fluconazole. Silver nanoparticles were prepared using wet chemical method and characterised by UV-Vis spectrophotometry, dynamic light scattering, and zeta potential. Broth microdilution and pour plates methods were used to study the anticandidal activity using two C. glabrata fluconazole-resistant strains (DSY565 and CBS138) known to overexpress active efflux pumps, and a standard fluconazole sensitive strain ATCC 22553. Silver nanoparticles-fluconazole combinations decreased concentrations of fluconazole substantially without compromising the activity. These findings suggest that AgNPs enhance the efficacy of fluconazole and offer a promising application in therapy of C. glabrata infections.

Candida glabrata Infection: A Rare Complication of Chest Trauma

Candida species are fungi, which are ubiquitous organisms. It is a normal flora of the oral cavity, genitourinary and gastrointestinal tract. An increasing incidence of fungal infections with Candida species has been noted in immunocompromised patients such as intensive care, postsurgical, and neutropenic patients. Candida species are detected in approximately 31 to 55% of healthy individuals. They are more common in immunocompromised individuals. Colonization rates increase with severity of illness and duration of hospitalization. We present a 32-year-old male who presented at our institution with a thoracoabdominal penetrating injury following assault. He had injury to the stomach and left hemi diaphragm, with moderate hemothorax. He had surgery done with repair of the stomach and diaphragm. He however developed chest infection with empyma thoracis thereafter. Culture of the pleural effluent revealed growth of Canddida glabrata which was sensitive to Ketoconazole. He was treated for two weeks and subsequently discharged from the ward and followed up in the clinic. Though C. glabrata infection of the chest is rare, it is however useful to exclude fungal infection in patients with empyema thoracic, as early diagnosis and treatment provides good outcome.

Research progress on Chinese and western medicine treatment for Candida glabrata infection

Research progress on Chinese and western medicine treatment for Candida glabrata infection

Candida Extracellular Nucleotide Metabolism Promotes Neutrophils Extracellular Traps Escape.

Host innate immunity is fundamental to the resistance against Candida albicans and Candida glabrata infection, two of the most important agents contributing to human fungal infections. Phagocytic cells, such as neutrophils, constitute the first line of host defense mechanisms, and the release of neutrophil extracellular traps (NETs) represent an important strategy to immobilize and to kill invading microorganisms, arresting the establishment of infection. The purinergic system operates an important role in the homeostasis of immunity and inflammation, and ectophosphatase and ectonucleotidase activities are recognized as essential for survival strategies and infectious potential of several pathogens. The expression and unique activity of a 3′-nucleotidase/nuclease (3′NT/NU), able to hydrolyze not only AMP but also nucleic acids, has been considered as part of a possible mechanism of microbes to escape from NETs. The aim of the present study was to evaluate if yeasts escape from the NET-mediated killing through their 3′NT/NU enzymatic activity contributing to NET-hydrolysis. After demonstrating the presence of 3′NT/NU activity in C. albicans, C. glabrata, and Saccharomyces cerevisiae, we show that, during neutrophils-Candida interaction, when NETs formation and release are triggered, NETs digestion occurs and this process of NETs disruption promoted by yeast cells was prevented by ammonium tetrathiomolybdate (TTM), a 3′NT/NU inhibitor. In conclusion, although the exact nature and specificity of yeasts ectonucleotidases are not completely unraveled, we highlight the importance of these enzymes in the context of infection, helping yeasts to overcome host defenses, whereby C. albicans and C. glabrata can escape NET-mediate killing through their 3′NT/NU activity.

Etoposide and Camptothecin Reduce Growth, Viability, the Generation of Petite Mutants, and Recognize the Active Site of DNA Topoisomerase I and II Enzymes in Candida glabrata.

The online version contains supplementary material available at 10.1007/s12088-021-00942-6.

Washed microbiota transplantation for the treatment of recurrent fungal infection in a patient with ulcerative colitis.

Washed microbiota transplantation for the treatment of recurrent fungal infection in a patient with ulcerative colitis.

Nasopharyngeal histoplasmosis– A rare case report

Histoplasmosis is a dimorphic fungus which is widely distributed among western countries like America and in some parts of the tropical region. It is acquired by inhaling microconidia. Depending on the immune status patient may develop acute or chronic pulmonary diseases or disseminated infection. The disseminated form of nasopharyngeal region can present as ulceration, rhino sinusitis, nasal obstruction, dyspnoea, hoarseness of voice and clinically it can mimic carcinoma. Microscopically, the differential diagnosis of histoplasmosis includes Leishmaniasis, Cryptococci neoformans, Candida glabrata, Pneumocystis jiroveci and Penicillium marneffei infections. The diagnosis of histoplasma is dependent on histopathological examination and demonstration by special stains, where the latter serves the gold standard in demonstrating organism on light microscopy. Keywords: Fungal infection, Histoplasmosis, Nasopharyngeal lesion, Paediatric age.