Candidemia in a Brazilian hospital: the importance of Candida parapsilosis

Clinical Characteristics of Candidemia Due to Candida parapsilosis with Serial Episodes: Insights from 5-Year Data Collection at a Tertiary Hospital in Korea

Candida parapsilosis is a common cause of non-albicans Candida species causing candidemia, particularly invasive candidiasis. This study aimed to characterize candidemia due to the C. parapsilosis complex with serial episodes, including clinical and mycological features.

METHODS

Blood isolates of the C. parapsilosis complex were collected from February 2019 to January 2023 at a tertiary Korean hospital. Species identification was performed using Vitek 2 or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antifungal susceptibility testing was performed using the Sensititre YeastOne® system. Clinical information was collected, and characteristics were analyzed according to single or serial isolates.

RESULTS

A total of 586 blood isolates of the C. parapsilosis complex were recovered from 68 candidemia patients during the study period. Of them, only the first isolate per patient was investigated. The only two isolates were resistant to fluconazole and no isolate was resistant to echinocandins, amphotericin B, or 5-FC. A single episode of candidemia occurred in 35 patients, while serial episodes occurred in 33 patients. Underlying liver diseases, use of vasopressors, ICU admission, severe sepsis, and CVC use were more frequent in patients with serial episodes. There was no significant difference in the median MIC values of antifungal agents or the use of azoles or amphotericin B between single and serial episodes. However, patients with serial episodes more frequently received echinocandin therapy. Overall, there was no significant difference in the 30-day mortality rate between patients with single and serial episodes.

CONCLUSION

Our data indicate that several factors related to the underlying conditions of the patients are associated with C. parapsilosis candidemia with serial episodes, rather than the characteristics of Candida itself.

Clinical, Epidemiological and Laboratory Features of Invasive Candida parapsilosis Complex Infections in a Brazilian Pediatric Reference Hospital during the COVID-19 Pandemic

The present study aimed to describe the clinical, epidemiological and laboratory characteristics of invasive candidiasis by C. parapsilosis complex (CPC) in a Brazilian tertiary pediatric hospital during the COVID-19 pandemic. Clinical samples were processed in the BACT/ALERT® 3D system or on agar plates. Definitive identification was achieved by MALDI-TOF MS. Antifungal susceptibility was initially analyzed by the VITEK 2 system (AST-YS08 card) and confirmed by the CLSI protocol. Patient data were collected from the medical records using a structured questionnaire. CPC was recovered from 124 patients over an 18-month period, as follows: C. parapsilosis (83.87%), C. orthopsilosis (13.71%) and C. metapsilosis (2.42%). Antifungal resistance was not detected. The age of the patients with invasive CPC infections ranged from <1 to 18 years, and most of them came from oncology-related sectors, as these patients were more affected by C. parapsilosis. C. orthopsilosis infections were significantly more prevalent in patients from critical care units. Invasive infections caused by different pathogens occurred in 75 patients up to 30 days after the recovery of CPC isolates. Overall, 23 (18.55%) patients died within 30 days of CPC diagnosis. Catheter removal and antifungal therapy were important measures to prevent mortality. COVID-19 coinfection was only detected in one patient.

Anti-inflammatory and anti-Candida Effects of Brazilian Organic Propolis, a Promising Source of Bioactive Molecules and Functional Food

Brazilian organic propolis (BOP) is an unexplored Brazilian propolis that is produced organically and certified according to international legislation. Our results showed that BOP has strong anti-inflammatory effects and acts by reducing nuclear factor κB activation, tumor necrosis factor α release, and neutrophil migration. In addition, BOP6 exhibited antifungal activity on planktonic and biofilm cultures of Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, and Candida parapsisolis and reduced in vitro yeast cell adhesion to human keratinocytes at sub-inhibitory concentrations. BOP demonstrated significantly low toxicity in Galleria melonella larvae at antifungal doses. Lastly, a chemical analysis revealed the presence of caffeoyltartaric acid, 3,4-dicaffeoylquinic acid, quercetin, and gibberellins A7, A9, and A20, which may be responsible for the biological properties observed. Thus, our data indicate that BOP is a promising source of anti-inflammatory and antifungal molecules that may be used as a functional food.

Molecular Docking and Quantum Studies of Lawsone Dimers Derivatives: New Investigation of Antioxidant Behavior and Antifungal Activity

BACKGROUND

In general, fungal species are characterized by their opportunistic character and can trigger various infections in immunocompromised hosts. The emergence of infections associated with high mortality rates is due to the resistance mechanisms that these species develop.

METHODS

This phenomenon of resistance denotes the need for the development of new and effective therapeutic approaches. In this paper, we report the investigation of the antioxidant and antifungal behavior of dimeric naphthoquinones derived from lawsone whose antimicrobial and antioxidant potential has been reported in the literature.

RESULTS

Seven fungal strains were tested, and the antioxidant potential was tested using the combination of the methodologies: reducing power, total antioxidant capacity and cyclic voltammetry. Molecular docking studies (PDB ID 5V5Z and 1EA1) were conducted which allowed the derivation of structureactivity relationships (SAR). Compound 1-i, derived from 3-methylfuran-2-carbaldehyde showed the highest antifungal potential with an emphasis on the inhibition of Candida albicans species (MIC = 0.5 µg/mL) and the highest antioxidant potential.

CONCLUSION

A combination of molecular modeling data and in vitro assays can help to find new solutions to this major public health problem.

Candidemia in a public hospital in Northeastern Brazil: Epidemiological features and risk factors in critically ill patients

BACKGROUND

Candidemia is a life-threatening fungal infection characterized by the presence of Candida in the blood.

AIMS

To describe the clinical-epidemiological features and main risk factors among patients with candidemia admitted to Intensive Care Unit.

METHODS

A cross-sectional, retrospective and observational study was performed between January 2015 and July 2016. Laboratory reports and medical records from ICU patients admitted to a public hospital in northeastern Brazil were analyzed.

RESULTS

There were 1573 admissions and 67 of them were positive for candidemia. The majority of patients were male (53.3%) and remained at the hospital for more than seven days (86.6%). Non-C. albicansCandida infections (60%) were predominant. Broad-spectrum antibiotic therapy was prescribed in 98.4% of the cases. The most frequent underlying diseases were sepsis (73.3%), presence of solid tumors (15%), respiratory condition (60%), urinary tract disease (56.6%) and gastrointestinal tract diseases (23.3%). Surgeries were carried out on 43% of the patients, consisting of 23.3% abdominal surgeries, with a mortality rate of 92.8%. Risk factors were venous central access (93.3%), mechanical ventilation (81.6%), nasoenteral tube (83.3%), nasogastric tube (25%), indwelling bladder catheter (88.3%), diabetes mellitus (55%) and tracheostomy (36.6%). Statistical analysis correlated the use of indwelling bladder catheter with a higher mortality rate (r=0.07412, p=0.0353).

CONCLUSIONS

The current study reveals the high case fatality rates among critically ill patients suffering from candidemia admitted to ICU. Herein, we highlight the importance of identifying non-C. albicansCandida species and reinforce the idea of carrying out epidemiological surveillances and antifungal susceptibility tests.

In vitro synergy of echinocandins with triazoles against fluconazole-resistant Candida parapsilosis complex isolates

INTRODUCTION

Candida parapsilosis (C. parapsilosis) is a common non-albicans Candida species ranked as the second common cause of bloodstream infections. Azole resistance and elevated echinocandin MICs have been reported for these fungi. This study was conducted to determine the interactions between azoles and echinocandins against C. parapsilosis species complex.

MATERIALS AND METHODS

Fifteen fluconazole-resistant clinical isolates of C. parapsilosis complex were included: C. parapsilosis sensu stricto (n = 7), C. orthopsilosis (n = 5) and C. metapsilosis (n = 3). The activity of azoles (fluconazole, itraconazole) and echinocandins (anidulafungin, micafungin) alone and in combination was determined using checkerboard broth microdilution. The results were determined based on the fractional inhibitory concentration index (FICI).

RESULTS

In vitro combination of fluconazole with anidulafungin was found to be synergistic (FICI 0.07-0.37) and decreased the MIC range from 4-64 μg/mL to 0.5-16 μg/mL for fluconazole and from 2-8 μg/mL to 0.125-1 μg/mL for anidulafungin. Similarly, interactions of fluconazole with micafungin (FICI 0.25-0.5), itraconazole with anidulafungin (FICI 0.15-0.37) and itraconazole with micafungin (FICI 0.09-0.37) were synergistic.

CONCLUSION

The combination of fluconazole and itraconazole with either anidulafungin or micafungin demonstrated synergistic interactions against C. parapsilosis species complex, especially against isolates with elevated MIC values. However, the use of these combinations in clinical practice and the clinical relevance of in vitro combination results remain unclear.

Impact of manganese on biofilm formation and cell morphology of Candida parapsilosis clinical isolates with different biofilm forming abilities

The commensal species Candida parapsilosis is an emerging human pathogen that has the ability to form biofilms. In this study, we explored the impact of the divalent cations cobalt (Co²⁺), copper (Cu²⁺), iron (Fe³⁺), manganese (Mn²⁺), nickel (Ni²⁺) and zinc (Zn²⁺) on biofilm formation of clinical isolates of C. parapsilosis with no, low and high biofilm forming abilities at 30 and 37°C. All strains besides one isolate showed a concentration-dependent enhancement of biofilm formation at 30°C in the presence of Mn²⁺ with a maximum at 2 mM. The biofilm forming ability of no and low biofilm forming isolates was >2-fold enhanced in the presence of 2 mM Mn²⁺, while the effect in high biofilm forming isolate was significantly less pronounced. Of note, cells in the biofilms of no and low biofilm forming strains differentiated into yeast and pseudohyphal cells similar in morphology to high biofilm formers. The biofilm transcriptional activator BCR1 has a dual developmental role in the absence and presence of 2 mM Mn²⁺ as it promoted biofilm formation of no biofilm forming strains, and, surprisingly, suppressed cells of no biofilm forming strains to develop into pseudohyphae and/or hyphae. Thus, environmental conditions can significantly affect the amount of biofilm formation and cell morphology of C. parapsilosis with Mn²⁺ to overcome developmental blocks to trigger biofilm formation and to partially relieve BCR1 suppressed cell differentiation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Salivary pH and colonization by oral Candida in children and adolescents submitted to haemodialysis

BACKGROUND

Fungal infections are a serious problem among haemodialysis patients.

AIM

The aims of this study were to estimate the frequency of oral Candida species among children and adolescents undergoing haemodialysis (HD), to identify the isolated species, and to study the relationship between haemodialysis duration, amounts of colony-forming units, and salivary pH.

DESIGN

A matched sample of 52 patients undergoing HD and 52 healthy individuals were selected. The samples were obtained from the dorsum of the tongue, and the colonies were identified through a substrate assimilation test. Stimulated whole saliva was collected from each patient for evaluation of salivary pH.

RESULTS

The frequency of oral Candida species was 34.6% (18/52) and 46.20% (24/52) in the HD and control groups (P = 0.23), respectively. Candida parapsilosis complex was the most frequently isolated fungi species in the HD group (P = 0.03). A HD therapy duration of more than 1 year was statistically correlated with a higher number of colony-forming units (P = 0.03) but was not statistically related to salivary pH.

CONCLUSIONS

Candida parapsilosis complex was the most frequently isolated fungal species in the young HD patients, and the duration therapy was associated with higher oral colonization.

Echinocandins for management of invasive candidiasis in patients with liver disease and liver transplantation

Candida species remains one of the most important causes of opportunistic infections worldwide. Invasive candidiasis (IC) is associated with considerable morbidity and mortality in liver disease (LD) patients if not treated promptly. Echinocandins are often recommended as a first-line empirical treatment for managing IC and can especially play a critical role in managing IC in LD patients. However, advanced LD patients are often immunocompromised and critically ill. Hence altered pharmacokinetics, drug interactions as well as tolerance issues of antifungal treatments are a concern in these patients. This comprehensive review examines the epidemiology, risk factors and diagnosis of IC in patients with LD and evaluates differences between three available echinocandins for treating this group of patients.

Yeast isolation and identification in water used in a Brazilian hemodialysis unit by classic microbiological techniques and Raman spectroscopy

The use of poorly treated water in hemodialysis centers may lead to fungal contamination, which poses a serious threat to immunologically debilitated hemodialysis patients. This study aimed to isolate and identify yeast species in the water of a Brazilian hemodialysis center by using classic microbiological techniques and Raman spectroscopy. For 12 months, a total of 288 water samples were collected from different points of the hemodialysis treatment distribution center. One hundred and forty-six yeast species were isolated and identified in the samples that tested positive for the presence of yeasts such as Candida parapsilosis (100 isolates, or 68.50%), C. guilliermondii (17 isolates, or 11.65%), Rhodotorula mucilaginosa (23 isolates, or 15.75%), R. glutinis (three isolates, or 2.05%), and Trichosporon inkin (three isolates, or 2.05%). Yeast susceptibility to the antifungal fluconazole was also assayed. Only two C. guilliermondii isolates were resistant to fluconazole: the minimal inhibitory concentrations were higher than 64 μg/mL. The different yeast species present in the water of a Brazilian hemodialysis center call for more effective water disinfection procedures in this unit. Raman spectroscopy is an excellent tool to identify yeast species and is potentially applicable in routine water monitoring in hemodialysis units.

Regulation of ERG3, ERG6, and ERG11 Genes in Antifungal-Resistant isolates of Candida parapsilosis

Background

Candida parapsilosis is one of the five common strains of yeasts involved in invasive candidiasis. The expression analysis of sterol biosynthesis pathway genes, which are associated with resistance, can assist the better understanding of antifungal resistance mechanisms.

Method

The antifungal susceptibility of 120 clinical C. parapsilosis isolates was examined. The changes in the gene expression related to resistance were analyzed.

Results

Eight strains were resistant to fluconazole (FLC), itraconazole (ITC), and amphotericin B (AMB). The regulation variations included increased mRNA levels of ERG3, ERG6, and ERG11 and decreased mRNA levels of ERG3 and ERG6 in response to FLC. ERG11 mRNA level increases in response to ITC and AMB.

Conclusion

The mechanism of resistance to azoles in C. parapsilosis is very similar to C. Albicans. This feature may help to design new treatment strategy for candidiasis.

Revisiting Species Distribution and Antifungal Susceptibility of Candida Bloodstream Isolates from Latin American Medical Centers

The epidemiology of candidemia varies geographically, and there is still scarce data on the epidemiology of candidemia in Latin America (LA). After extensive revision of medical literature, we found reliable and robust information on the microbiological aspects of candidemia in patients from 11 out of 21 medical centers from LA countries and 1 out of 20 from Caribbean countries/territories. Based on 40 papers attending our search strategy, we noted that C. albicans remains the most common species causing candidemia in our region, followed by C. parapsilosis and C. tropicalis. In Argentina, Brazil, and Colombia, a trend towards an increase in frequency of C. glabrata candidemia was observed. Although resistance rates to fluconazole is under 3%, there was a slight increase in the resistance rates to C. albicans, C. parapsilosis and C. tropicalis isolates. Echinocandin resistance has been reported in a few surveys, but no single study confirmed the resistant phenotype reported by using molecular methods. We highlight the importance of conducting continuous surveillance studies to identify new trends in terms of species distribution of Candida and antifungal resistance related to episodes of candidemia in LA. This information is critical for helping clinicians to prevent and control Candida bloodstream infections in their medical centers.

Outcome of Candida Parapsilosis Complex Infections Treated with Caspofungin in Children

BACKGROUND

We aimed to evaluate the correlation of caspofungin E-tests with the prognosis and response to caspofungin therapy of Candida parapsilosis complex bloodstream infections in children hospitalized in a pediatric intensive care unit.

METHODS

All children who had C. parapsilosis complex bloodstream infections and who were treated with caspofungin were included in this retrospective study. For each patient, the following parameters, including all consecutive blood and central venous catheter (CVC) cultures, the duration between diagnosis and CVC removal, mortality rate, relapses of the C. parapsilosis complex infections as well as the demographic features, were recorded.

RESULTS

The central venous catheter survival rate was 33.3% under caspofungin treatment. In 92.4 % of the patients, the negative culture was achieved within a median duration of 12.5 days. The rate of relapses was 18.9%. The overall mortality rate was 37.7% (20 of 53 patients), and the 30-days mortality rate was 7.5% (4 of 53 patients). There was no statistically significant difference between the groups with MIC<2 mg/l and MIC =2 mg/l using CVC survival rate; rate and duration of achieving negative blood culture for C. parapsilosis complex; duration of hospital stay; rate and duration of relapses; overall mortality and 30-days mortality.

CONCLUSIONS

The beneficial effects of Caspofungin on biofilms has been shown in vivo, while its impact in children for maintenance of CVC was limited in our study but should not be underestimated in children who strongly need the presence of CVCs. The clinicians should weigh their priority for their patients and choose the optimal antifungal therapy for C. parapsilosis complex infections in children.

Study of strains of Candida spp. Isolated from catheters in UHC of Oran (Algeria): Identification and antifungal susceptibility

OBJECTIVES

The increasing incidence of Candida spp., and the vital prognosis often compromise for patients with Candida species make urgent the exact knowledge of their distribution worldwide and exhaust action antifungals currently used in clinical. That why we carry out an epidemiological study of Candida species and testing their susceptibility against two antifungals: amphotericin B and caspofungin.

MATERIALS AND METHODS

Samplings of peripheral venous catheters (PVC) were carried out from during 8months on the services of Internal medicine, Surgery A and Neonatology of Oran's University Hospital Center (UHC). The study of the susceptibility of Candida species to antifungal agents was performed according to the Clinical Laboratory Standards Institute (CLSI 2008).

RESULTS

From 300 samples, 25 yeasts were isolated. The rate of colonization PVC was 8.33% by Candida spp. The most isolated strains were Candida parapsilosis with 64% of cases, followed by Candida albicans (12%) then 8% for Candida glabrata and Candida krusei. However, only 4% of isolates were Candida famata or Candida lusitaniae. Furthermore all isolated strains were susceptible to amphotericin B with Minimum Inhibitory Concentrations (MIC) ranging from 0.25 to 1μg/mL. MIC obtained with caspofungin vary from 0.0625 to 2μg/mL for all strains. Moreover, one strain of C. krusei is resistant to caspofungin with a MIC superior to 8μg/mL.

CONCLUSION

All though caspofungin is at least as effective as amphotericin B, it is better tolerated for the treatment of invasive fungal infections.

Application of MALDI-TOF MS for requalification of a Candida clinical isolates culture collection

Microbial culture collections underpin biotechnology applications and are important resources for clinical microbiology by supplying reference strains and/or performing microbial identifications as a service. Proteomic profiles by MALDI-TOF MS have been used for Candida spp. identification in clinical laboratories and demonstrated to be a fast and reliable technique for the routine identification of pathogenic yeasts. The main aim of this study was to apply MALDI-TOF MS combined with classical phenotypic and molecular approaches to identify Candida clinical isolates preserved from 1 up to 52 years in a Brazilian culture collection and assess its value for the identification of yeasts preserved in this type of collections. Forty Candida spp. clinical isolates were identified by morphological and biochemical analyses. Identifications were also performed by the new proteomic approach based on MALDI-TOF MS. Results demonstrated 15% discordance when compared with morphological and biochemical analyses. Discordant isolates were analysed by ITS sequencing, which confirmed the MALDI-TOF MS identifications and these strains were renamed in the culture collection catalogue. In conclusion, proteomic profiles by MALDI-TOF MS represents a rapid and reliable method for identifying clinical Candida species preserved in culture collections and may present clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals.

The calcineurin inhibitor cyclosporin A exhibits synergism with antifungals against Candida parapsilosis species complex

Candida parapsilosis complex comprises three closely related species, C. parapsilosis sensu stricto, Candida metapsilosis and Candida orthopsilosis. In the last decade, antifungal resistance to azoles and caspofungin among C. parapsilosis sensu lato strains has been considered a matter of concern worldwide. In the present study, we evaluated the synergistic potential of antifungals and the calcineurin inhibitor cyclosporin A (Cys) against planktonic and biofilms of C. parapsilosis complex from clinical sources. Susceptibility assays with amphotericin, fluconazole, voriconazole, caspofungin and Cys were performed by microdilution in accordance with Clinical and Laboratory Standards Institute guidelines. Synergy testing against planktonic cells of C. parapsilosis sensu lato strains was assessed by the chequerboard method. Combinations formed by antifungals with Cys were evaluated against mature biofilms in microtitre plates. No differences in the antifungal susceptibility pattern among species were observed, but C. parapsilosis sensu stricto strains were more susceptible to Cys than C. orthopsilosis and C. metapsilosis. Synergism between antifungals and Cys was observed in C. parapsilosis sensu lato strains. Combinations formed by antifungals and Cys were able to prevent biofilm formation and showed an inhibitory effect against mature biofilms of C. parapsilosis sensu stricto, C. metapsilosis and C. orthopsilosis. These results strengthen the potential of calcineurin inhibition as a promising approach to enhance the efficiency of antifungal drugs.

Systemic Infection Due to Candida parapsilosis in a Domestic Ferret (Mustela putorius furo)

An 18-month-old castrated male ferret (Mustela putorius furo) was presented to the veterinary hospital for acute collapse but died despite initiation of emergency treatment. The body was submitted for a complete postmortem examination. The pathologist determined the ferret was suffering from severe necrotizing encephalitis, necrogranulomatous mediastinal lymphadenitis, and ulcerative dermatitis attributable to systemic Candida parapsilosis. This is the first report of systemic Candida parapsilosis in a ferret.

Six-year trend analysis of nosocomial candidemia and risk factors in two intensive care hospitals in Mato Grosso, midwest region of Brazil

We conducted this cross-sectional retrospective study using clinical and laboratory data from two tertiary hospitals in Cuiabá, Mato Grosso, Brazil, in order to explore the risk factors and estimate mortality, prevalence and lethality of candidemia between 2006 and 2011. A total of 130 episodes of candidemia were identified. The prevalence of candidemia was 1.8 per 1,000 admissions, the mortality rate was 0.9 per 1,000 admissions, and the lethality was 49.2 %. The main agent in this population was Candida parapsilosis (n = 50), followed by C. albicans (n = 45). Comparison between the numbers of episodes in the two triennia revealed that the non-albicans group grew by 48.2 %. The distribution of yeast species of Candida per hospital unit revealed that C. albicans was more prevalent than C. parapsilosis in the adult ICU and C. parapsilosis was more prevalent than C. albicans in the neonatal ICU. Patients remained hospitalized for an average of 53.5 days. Central venous catheters, parenteral nutrition and age were the variables that proved to be independent in the multivariate analysis and that maintained a statistically significant association with the incidence of death in patients with candidemia. The annual prevalence of candidemia showed a significant increase in the second triennium (2009-2011) compared with the first (2006-2008) probably due to increased exposure to risk factors: central venous catheter, H2 blockers, nutrition parenteral corticosteroids and mean hospital duration.

Species of Candida as a component of the nasal microbiota of healthy horses

Respiratory infections are a common problem among equines and occur with variable rates of morbidity and mortality. Although some fungal species are considered primary agents of respiratory tract infections in several mammals, their relevance in respiratory diseases of equines is frequently neglected. In the present study, we performed an active search for Candida spp. in the nasal cavity of horses. The presence of Candida spp. was investigated through the use of nasal swabs that were streaked on culture media. These yeasts were identified through physiological testing and their in vitro antifungal susceptibility were also characterized. The analysis of the material from the nasal cavity of 97 randomly chosen horses resulted in the isolation of Candida spp. from 35 animals (36.08%), out of which 18 (32.14%) were C. famata, 14 (25%) C. parapsilosis, 12 (21.42%) Meyerozyma guilliermondii (C. guilliermondii), 11 (19.64%) C. tropicalis and 1 (1.78%) Wickerhamomyces anomalus (C. pelliculosa). The minimum inhibitory concentration (MIC) values ranged from 0.03125-1 μg/ml for amphotericin B; and from 0.03125-> 16 μg/ml and 0.125 to > 64 μg/ml for itraconazole and fluconazole, respectively. Resistance to fluconazole and itraconazole was observed among C. tropicalis (n = 3) and C. guilliermondii (n = 1). The data show a predominance of non-C. albicans Candida species in the nasal microbiota of healthy equines, including antifungal resistant isolates, reiterating the importance of monitoring fungal pathogens in these animals.

Candida parapsilosis is a significant neonatal pathogen: a systematic review and meta-analysis

BACKGROUND

Candida is the third most common cause of late-onset neonatal sepsis in infants born at <1500 g. Candida parapsilosis infections are increasingly reported in preterm neonates in association with indwelling catheters.

METHODS

We systematically reviewed neonatal literature and synthesized data pertaining to percentage of C. parapsilosis infections and mortality by meta-analyses. We also reviewed risk factors, virulence determinants, antimicrobial susceptibility patterns and outlined clinical management strategies.

RESULTS

C. parapsilosis infections comprised 33.47% (95% confidence interval [CI]: 30.02, 37.31) of all neonatal Candida infections. C. parapsilosis rates were similar in studies performed before the year 2000, 33.53% (95% CI: 30.06, 37.40) (28 studies), to those after 2000, 27.00% (95% CI: 8.25, 88.37) (8 studies). The mortality due to neonatal C. parapsilosis infections was 10.02% (95% CI: 7.66, 13.12). Geographical variations in C. parapsilosis infections included a low incidence in Europe and higher incidence in North America and Australia. Biofilm formation was a significant virulence determinant and predominant risk factors for C. parapsilosis infections were prematurity, prior colonization and catheterization. Amphotericin B remains the antifungal drug of choice and combination therapy with caspofungin or other echinocandins may be considered in resistant cases.

CONCLUSION

C. parapsilosis is a significant neonatal pathogen, comprises a third of all Candida infections and is associated with 10% mortality. Availability of tools for genetic manipulation of this organism will identify virulence determinants and organism characteristics that may explain predilection for preterm neonates. Strategies to prevent horizontal transmission in the neonatal unit are paramount in decreasing infection rates.

Effectiveness of disinfectants used in hemodialysis against both Candida orthopsilosis and C. parapsilosis sensu stricto biofilms

Biofilms have been observed in the fluid pathways of hemodialysis machines. The impacts of four biocides used for the disinfection of hemodialysis systems were tested against Candida parapsilosis sensu stricto and Candida orthopsilosis biofilms generated by isolates obtained from a hydraulic circuit that were collected in a hemodialysis unit. Acetic acid was shown to be the most effective agent against Candida biofilms. Strategies for effective disinfection procedures used for hemodialysis systems should also seek to kill and inhibit biofilms.

Candida spp. isolated from inpatients, the environment, and health practitioners in the Pediatric Unit at the Universitary Hospital of the Jundiaí Medical College, State of São Paulo, Brazil

INTRODUCTION

This study aimed to isolate and identify Candida spp. from the environment, health practitioners, and patients with the presumptive diagnosis of candidiasis in the Pediatric Unit at the Universitary Hospital of the Jundiaí Medical College, to verify the production of enzymes regarded as virulence factors, and to determine how susceptible the isolated samples from patients with candidiasis are to antifungal agents.

METHODS

Between March and November of 2008 a total of 283 samples were taken randomly from the environment and from the hands of health staff, and samples of all the suspected cases of Candida spp. hospital-acquired infection were collected and selected by the Infection Control Committee. The material was processed and the yeast genus Candida was isolated and identified by physiological, microscopic, and macroscopic attributes.

RESULTS

The incidence of Candida spp. in the environment and employees was 19.2%. The most frequent species were C. parapsilosis and C. tropicalis among the workers, C. guilliermondii and C. tropicalis in the air, C. lusitanae on the contact surfaces, and C. tropicalis and C. guilliermondii in the climate control equipment. The college hospital had 320 admissions, of which 13 (4%) presented Candida spp. infections; three of them died, two being victims of a C. tropicalis infection and the remaining one of C. albicans. All the Candida spp. in the isolates evidenced sensitivity to amphotericin B, nystatin, and fluconazole.

CONCLUSIONS

The increase in the rate of hospital-acquired infections caused by Candida spp. indicates the need to take larger measures regarding recurrent control of the environment.

Candida parapsilosis complex water isolates from a haemodialysis unit: biofilm production and in vitro evaluation of the use of clinical antifungals

Candida parapsilosis, currently divided into three distinct species, proliferates in glucose-rich solutions and has been associated with infections resulting from the use of medical devices made of plastic, an environment common in dialysis centres. The aims of this study were (i) to screen for Candida orthopsilosis and Candida metapsilosis (100 environmental isolates previously identified as C. parapsilosis), (ii) to test the ability of these isolates to form biofilm and (iii) to investigate the in vitro susceptibility of Candida spp biofilms to the antifungal agents, fluconazole (FLC) and amphotericin B (AMB). Isolates were obtained from a hydraulic circuit collected from a haemodialysis unit. Based on molecular criteria, 47 strains were re-identified as C. orthopsilosis and 53 as C. parapsilosis. Analyses using a formazan salt reduction assay and total viable count, together with microscopy studies, revealed that 72 strains were able to form biofilm that was structurally similar, but with minor differences in morphology. A microtitre-based colorimetric assay used to test the susceptibility of fungal biofilms to AMB and FLC demonstrated that the C. parapsilosis complex displayed an increased resistance to these antifungal agents. The results from these analyses may provide a basis for implementing quality controls and monitoring to ensure the microbiological purity of dialysis water, including the presence of yeast.

Species distribution and in vitro fluconazole susceptibility of clinical Candida isolates in a Brazilian tertiary-care hospital over a 3-year period

INTRODUCTION

In this study, we aimed at identifying Candida isolates obtained from blood, urine, tracheal secretion, and nail/skin lesions from cases attended at the Hospital Universitário de Londrina over a 3-year period and at evaluating fluconazole susceptibilities of the isolates.

METHODS

Candida isolates were identified by polymerase chain reaction (PCR) using species-specific forward primers. The in vitro fluconazole susceptibility test was performed according to EUCAST-AFST reference procedure.

RESULTS

Isolates were obtained from urine (53.4%), blood cultures (19.2%), tracheal secretion (17.8%), and nail/skin lesions (9.6%). When urine samples were considered, prevalence was similar in women (45.5%) and in men (54.5%) and was high in the age group >61 years than that in younger ones. For blood samples, prevalence was high in neonates (35%) and advanced ages (22.5%). For nail and skin samples, prevalence was higher in women (71.4%) than in men (28.6%). Candida albicans was the most frequently isolated in the hospital, but Candida species other than C. albicans accounted for 64% of isolates, including predominantly Candida tropicalis (33.2%) and Candida parapsilosis (19.2%). The trend for non-albicans Candida as the predominant species was noted from all clinical specimens, except from urine samples. All Candida isolates were considered susceptible in vitro to fluconazole with the exception of isolates belonging to the intrinsically less-susceptible species C. glabrata.

CONCLUSIONS

Non-albicans Candida species were more frequently isolated in the hospital. Fluconazole resistance was a rare finding in our study.

Candida parapsilosis candidaemia in a neonatal unit over 7 years: a case series study

OBJECTIVE

To evaluate Candida parapsilosis candidaemia in a neonatal unit over 7 years.

DESIGN

Case series study.

SETTING

A 2000-bed tertiary-care university hospital at São Paulo, Brazil.

PARTICIPANTS

Neonates hospitalised in a 63-bed neonatal unit.

PRIMARY AND SECONDARY OUTCOME MEASURES

We evaluated the incidence of C parapsilosis fungemia in a neonatal unit from 2002 through 2008 and the main microbiological, clinical and epidemiological aspects of this disease in neonates. During the study period an outbreak occurred, an infection control programme was implemented, and isolates from blood and hand healthcare workers (HCWs) were submitted to molecular typing.

RESULTS

During 7 years, there were 36 cases of C parapsilosis fungaemia and annual incidence varied from 0 to 19.7 per 1000 admissions. Evaluating 31 neonates with fungemia, the mean age at diagnosis was 19 days. All children except for one were premature; all had received total parenteral nutrition and all but one had used central venous catheter. Three neonates had received antifungal treatment previously to the diagnosis. Thirty-day mortality was 45%. Only lower birthweight was associated with mortality. C parapsilosis species complex was isolated from hand cultures in eight (11%) of the HCWs (one isolate was identified as C orthopsilosis). By molecular typing no HCW isolate was similar to any of the blood isolates.

CONCLUSIONS

The incidence of C parapsilosis fungemia in a neonatal unit varied widely over 7 years. We observed in our series a higher death rate than that reported in European countries and the USA.

Effect of usnic acid on Candida orthopsilosis and C. parapsilosis

The activity of usnic acid against Candida orthopsilosis and Candida parapsilosis on planktonic and biofilm conditions was investigated by using a broth microdilution and microplate methods. Potent in vitro activities against different Candida species were obtained. The metabolic activity of sessile cells of C. parapsilosis complex was reduced by 80% at four times the 80% inhibitory concentration. The in vitro studies support further efforts to determine whether usnic acid can be used clinically to cure patients with Candida infections.

Anticandidal efficacy of cinnamon oil against planktonic and biofilm cultures of Candida parapsilosis and Candida orthopsilosis

Candida parapsilosis is yeast capable of forming biofilms on medical devices. Novel approaches for the prevention and eradication of the biofilms are desired. This study investigated the anticandidal activity of sixteen essential oils on planktonic and biofilm cultures of C. parapsilosis complex. We used molecular tools, enumeration of colony-forming units, the colourimetric MTT assay, scanning electron microscopy (SEM) and a chequerboard assay coupled with software analyses to evaluate the growth kinetics, architecture, inhibition and reduction in biofilms formed from environmental isolates of the Candida parapsilosis complex; further, we also evaluated whether essential oils would interact synergistically with amphotericin B to increase their anticandidal activities. Of the environmental C. parapsilosis isolates examined, C. parapsilosis and C. orthopsilosis were identified. Biofilm growth on polystyrene substrates peaked within 48 h, after which growth remained relatively stable up to 72 h, when it began to decline. Details of the architectural analysis assessed by SEM showed that C. parapsilosis complex formed less complex biofilms compared with C. albicans biofilms. The most active essential oil was cinnamon oil (CO), which showed anticandidal activity against C. orthopsilosis and C. parapsilosis in both suspension (minimum inhibitory concentration-MIC-250 and 500 μg/ml) and biofilm (minimum biofilm reduction concentration-MBRC-1,000 and 2,000 μg/ml) cultures. CO also inhibited biofilm formation (MBIC) at concentrations above 250 μg/ml for both species tested. However, synergism with amphotericin B was not observed. Thus, CO is a natural anticandidal agent that can be effectively utilised for the control of the yeasts tested.

Species distribution and susceptibility profile of Candida species in a Brazilian public tertiary hospital

Background

Species identification and antifungal susceptibility tests were carried out on 212 Candida isolates obtained from bloodstream infections, urinary tract infections and dialysis-associated peritonitis, from cases attended at a Brazilian public tertiary hospital from January 1998 to January 2005.

Findings

Candida albicans represented 33% of the isolates, Candida parapsilosis 31.1%, Candida tropicalis 17.9%,Candida glabrata 11.8%, and others species 6.2%. In blood culture, C. parapsilosis was the most frequently encountered species (48%). The resistance levels to the antifungal azoles were relatively low for the several species, except for C. tropicalis and C. glabrata. Amphotericin B resistance was observed in 1 isolate of C. parapsilosis.

Conclusions

The species distribution and antifungal susceptibility herein observed presented several epidemiological features common to other tertiary hospitals in Latin American countries. It also exhibited some peculiarity, such as a very high frequency of C. parapsilosis both in bloodstream infections and dialysis-associated peritonitis. C. albicans also occurred in an important number of case infections, in all evaluated clinical sources. C. glabrata presented a high proportion of resistant isolates. The data emphasize the necessity to carry out the correct species identification accompanied by the susceptibility tests in all tertiary hospitals.

Candida bloodstream infection: data from a teaching hospital in Mato Grosso do Sul, Brazil

The incidence of Candida bloodstream infection has increased over the past years. In the Center-West region of Brazil, data on candidemia are scarce. This paper reports a retrospective analysis of 96 cases of Candida bloodstream infection at a Brazilian tertiary-care teaching hospital in the state of Mato Grosso do Sul, from January 1998 to December 2006. Demographic, clinical and laboratory data were collected from medical records and from the hospital's laboratory database. Patients' ages ranged from three days to 92 years, with 53 (55.2%) adults and 43 (44.8%) children. Of the latter, 25 (58.1%) were newborns. The risk conditions most often found were: long period of hospitalization, utilization of venous central catheter, and previous use of antibiotics. Fifty-eight (60.4%) patients died during the hospitalization period and eight (13.7%) of them died 30 days after the diagnosis of candidemia. Candida albicans (45.8%) was the most prevalent species, followed by C. parapsilosis (34.4%), C. tropicalis (14.6%) and C. glabrata (5.2%). This is the first report of Candida bloodstream infection in the state of Mato Grosso do Sul and it highlights the importance of considering the possibility of invasive Candida infection in patients exposed to risk factors, particularly among neonates and the elderly.

The anatomical distribution and antimicrobial susceptibility of yeast species isolated from healthy dogs

The aim of this work was to identify the predominant yeast species present at different anatomical sites in healthy dogs and to determine their in vitro antimicrobial susceptibility using a broth microdilution assay. Samples were collected from the preputial, vaginal, oral and perianal mucosae and the isolates cultured were identified according to their morphological characteristics and biochemical profile. Malassezia pachydermatis was the most commonly isolated yeast, followed by Candida parapsilosis, Candida tropicalis, Candida albicans, Saccharomyces cerevisiae and Rhodotorula spp. Minimum inhibitory concentrations of the azole derivatives ketoconazole, itraconazole and fluconazole against Candida spp. were 0.03-16 microg/mL, 0.06 to >16 microg/mL and 0.5-64 microg/mL, respectively and Candida isolates were sensitive to caspofungin and amphotericin B. Although all isolates of M. pachydermatis were sensitive to itraconazole, fluconazole, ketoconazole and amphotericin B, they were found to be resistant to caspofungin. The study has highlighted that Candida spp., M. pachydermatis, S. cerevisiae and Rhodotorula spp. are part of the normal canine surface microbiota and some of these organisms exhibit in vitro resistance to commonly used antimicrobials.

Candida parapsilosis, an emerging fungal pathogen

SUMMARY

Candida parapsilosis is an emerging major human pathogen that has dramatically increased in significance and prevalence over the past 2 decades, such that C. parapsilosis is now one of the leading causes of invasive candidal disease. Individuals at the highest risk for severe infection include neonates and patients in intensive care units. C. parapsilosis infections are especially associated with hyperalimentation solutions, prosthetic devices, and indwelling catheters, as well as the nosocomial spread of disease through the hands of health care workers. Factors involved in disease pathogenesis include the secretion of hydrolytic enzymes, adhesion to prosthetics, and biofilm formation. New molecular genetic tools are providing additional and much-needed information regarding C. parapsilosis virulence. The emerging information will provide a deeper understanding of C. parapsilosis pathogenesis and facilitate the development of new therapeutic approaches for treating C. parapsilosis infections.

Geographic and temporal trends in isolation and antifungal susceptibility of Candida parapsilosis: a global assessment from the ARTEMIS DISK Antifungal Surveillance Program, 2001 to 2005

We examined data from the ARTEMIS DISK Antifungal Surveillance Program to describe geographic and temporal trends in the isolation of Candida parapsilosis from clinical specimens and the in vitro susceptibilities of 9,371 isolates to fluconazole and voriconazole. We also report the in vitro susceptibility of bloodstream infection (BSI) isolates of C. parapsilosis to the echinocandins, anidulafungin, caspofungin, and micafungin. C. parapsilosis represented 6.6% of the 141,383 isolates of Candida collected from 2001 to 2005 and was most common among isolates from North America (14.3%) and Latin America (9.9%). High levels of susceptibility to both fluconazole (90.8 to 95.8%) and voriconazole (95.3 to 98.1%) were observed in all geographic regions with the exception of the Africa and Middle East region (79.3 and 85.8% susceptible to fluconazole and voriconazole, respectively). C. parapsilosis was most often isolated from blood and skin and/or soft tissue specimens and from patients hospitalized in the medical, surgical, intensive care unit (ICU) and dermatology services. Notably, isolates from the surgical ICU were the least susceptible to fluconazole (86.3%). There was no evidence of increasing azole resistance over time among C. parapsilosis isolates tested from 2001 to 2005. Of BSI isolates tested against the three echinocandins, 92, 99, and 100% were inhibited by concentrations of < or = 2 microg/ml of anidulafungin (621 isolates tested), caspofungin (1,447 isolates tested), and micafungin (539 isolates tested), respectively. C. parapsilosis is a ubiquitous pathogen that remains susceptible to the azoles and echinocandins; however, both the frequency of isolation and the resistance of C. parapsilosis to fluconazole and voriconazole may vary by geographic region and clinical service.

Epidemiology of candidemia in a tertiary care centre of north India: 5-year study

BACKGROUND

To determine the distribution of species of Candida and the risk factors associated with candidemia in Indian population for which we conducted a retrospective study for 5 years in a tertiary care centre of North India.

MATERIALS AND METHODS

Blood samples from 7,297 patients aged from 3 days to 85 years, suspected with candidemia, were collected and tested for Candida. The susceptibility patterns toward fluconazole for the year 2005 isolates were tested by micro-dilution assay as described in the CLSI (M27A-2 method).

RESULTS

Most of the episodes have been caused by species other than C. albicans. Non-albicans candidemia was 79%-80% in both female and male populations. The most frequent species isolated from 275 patients in 5 years (January 2001-December 2005) was C. tropicalis (35.3%), followed by C. albicans (21.5%), C. parapsilosis (20%), C. glabrata (17.5%), C. krusei (3.3%), C. haemulonii (1.5%), and C. guilliermondii (1%). C. parapsilosis was the predominant in the fifth year of the study (2004-2005). Dose-dependent susceptibility to fluconazole was observed in 5% (n = 3) of the strains. Antifungal resistance was found in 11.7% (n = 7), which includes only C. glabrata.

CONCLUSION

These results were comparable to those derived from other regions of India. C. tropicalis has been reported as the predominant species involved in the cases of candidemia. But in 2005 it has moved toward C. parapsilosis. No true antifungal resistance is reported. Further epidemiological surveillance is needed.

Species distribution and antifungal susceptibility patterns of Candida spp. bloodstream isolates from a Brazilian tertiary care hospital

In this work, we collect data from surveys of bloodstream Candida isolates performed in Brazil from 1996 to 2004. Besides, we analyzed the species distribution of bloodstream Candida isolates together with potential risk factors for candidemia and the susceptibility profile of these isolates in patients from Hospital das Clínicas in Goiânia city, Brazil. Blood samples were collected in the admission day and on every 7 days, in the intensive care unit (ICU) of a tertiary hospital. Candida isolates were identified by standard protocols that included germ tube formation, chlamydoconidia production on cornmeal agar and sugar fermentation and assimilation tests. Data of patients were recorded and analyzed according to age at the time of diagnosis, gender and presence of potential risk factors. Statistical analysis was used to determine if the time of hospital permanence increased Candida colonization in ICU patients' blood. The antifungal susceptibility testing was performed by broth microdilution method according to document NCCLS/CLSI M27-A2. Among the 345 blood samples cultured, candidemia was recovered in 33 patients, which were isolated 51.5% of Candida non-albicans. Fungemia was associated with long-term hospitalization. Fluconazole, itraconzole, voriconazole and amphotericin B exhibited a potent activity against all isolates of Candida. Voriconazole MICs were much low for all isolates tested. This work confirms data of increase of Candida non-albicans species in bloodstream in ICU and shows that voriconazole in vitro activity was higher than those of itraconazole, fluconazole and amphotericin B.