scholarly journals Virulence Factors Contributing to Pathogenicity ofCandida tropicalisand Its Antifungal Susceptibility Profile

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Sachin C. Deorukhkar ◽  
Santosh Saini ◽  
Stephen Mathew
Keyword(s):  
Virulence Factors ◽  
Biofilm Formation ◽  
Antifungal Susceptibility ◽  
Common Species ◽  
Blood Cultures ◽  
Haemolytic Activity ◽  
Phospholipase Activity ◽  
Fluconazole Resistance ◽  
Activity Maximum ◽  
The Past

The incidence of invasive candidiasis has increased over the past few decades. AlthoughCandida albicansremains by far the most common species encountered, in recent years shift towards non-albicans Candidaspecies likeCandida tropicalisis noted. Here in this study we determined the virulence factors and antifungal susceptibility profile of 125C. tropicalisisolated from various clinical specimens. Biofilm formation was seen in 53 (42.4%) isolates. Coagulase production was noted in 18 (14.4%) isolates. Phospholipase enzyme was the major virulent factor produced byC. tropicalisisolates. A total of 39 biofilm forming isolates showed phospholipase activity. Proteinase activity was demonstrated by 65 (52%) isolates. A total of 38 (30.4%) isolates showed haemolytic activity. Maximum isolates demonstrated resistance to fluconazole. Fluconazole resistance was more common inC. tropicalisisolated from blood cultures. Antifungal resistance was more in isolates possessing the ability to produce phospholipase and biofilm.C. tropicalisexhibit a great degree of variation not only in their pathogenicity but also in their antifungal susceptibility profile. The identification of virulence attributes specific for each species and their correlation with each other will aid in the understanding of the pathogenesis of infection.

scholarly journals Virulence Factors and Azole-Resistant Mechanism of Candida Tropicalis Isolated From Candidemia

2021 ◽  
Author(s):  
Elahe Sasani ◽  
Sadegh Khodavaisy ◽  
Sassan Rezaie ◽  
Mohammadreza Salehi ◽  
Muhammad Getso ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Candida Tropicalis ◽  
Biofilm Formation ◽  
Molecular Mechanisms ◽  
Antifungal Susceptibility ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Azole Resistance ◽  
Virulence Determinants ◽  
Fluconazole Resistant

Abstract Background Virulence factors intensify the pathogenicity of Candida species in candidemia. Limited knowledge exists regarding the azole-resistant mechanism and virulence factors of Candida tropicalis. Consequently, we aimed to evaluate the virulence factors and the molecular mechanisms of azole resistance among C. tropicalis isolated from bloodstream infection. Materials and methods Forty-five C. tropicalis isolates recovered from candidemia patients were evaluated for virulence factors, including extracellular enzymatic activities, cell surface hydrophobicity (CHS), and biofilm formation. Antifungal susceptibility pattern and expression level of ERG11, UPC2, MDR1, and CDR1 genes of eight azole resistance C. tropicalis isolates were assessed. Results The isolates expressed different frequencies of virulence determinants as follows: coagulase 4 (8.9%), phospholipase 4 (8.9 %), proteinase 31 (68.9 %), CSH 43 (95.6 %), esterase 43 (95.6 %), hemolysin 44 (97.8%), and biofilm formation 45 (100%). All the isolates were susceptible to amphotericin B and showed the highest resistance to voriconazole. The high expression of ERG11 and UPC2 genes in fluconazole-resistant C. tropicalis isolates were observed. Conclusion C. tropicalis isolated from candidemia patients extensively displayed capacities for biofilm formation, hemolysis, esterase activity, and hydrophobicity. In addition, the overexpression of ERG11 and UPC2 genes can be considered as one of the possible mechanisms of azole resistance.

scholarly journals Virulence Factors and Antifungal Susceptibility Profile of C. tropicalis Isolated from Various Clinical Specimens in Alexandria, Egypt

2021 ◽  
Vol 7 (5) ◽  
pp. 351
Author(s):  
Mohammed A. El-Kholy ◽  
Ghada F. Helaly ◽  
Ebtisam F. El Ghazzawi ◽  
Gamal El-Sawaf ◽  
Sherine M. Shawky
Keyword(s):  
Virulence Factors ◽  
Biofilm Formation ◽  
Antifungal Susceptibility ◽  
Accurate Identification ◽  
Icu Patients ◽  
Clinical Specimens ◽  
High Incidence ◽  
Invasive Infections ◽  
Vitek 2 ◽  
Urinary Isolates

Background: The incidence of candidiasis caused by non-albicans Candida (NAC) species is increasing. Candida tropicalis has emerged as one of the most important NAC species. This study aims to examine the antifungal susceptibility profile and some virulence factors of C. tropicalis isolated from various clinical specimens. Methods: A total of 71 C. tropicalis isolates from various clinical specimens (69.01%, 18.31%, 9.86%, and 2.82% of isolates were collected from urine, respiratory samples, blood, and skin and soft tissue infections, respectively) from ICU patients in Alexandria, Egypt. The isolates were identified at species level by CHROMagar Candida and VITEK 2 compact system. Furthermore, the antifungal susceptibility was determined using the VITEK 2 system AST-YS07 card containing different antifungals. Hemolysin, phospholipase, and proteinase activity and biofilm formation were also tested as virulence factors. Results: Only 30 isolates (42.25%) were non-susceptible (MIC ≥ 4 µg/mL) to fluconazole, of which 28 isolates showed non-susceptibility (MIC ≥ 0.25 µg/mL) to voriconazole. All isolates showed both hemolysin and proteinase activities, while only 9 isolates (12.68%) showed phospholipase production and 70 isolates (98.59%) demonstrated biofilm formation. Strong biofilm production was observed among the blood culture isolates (85.71%), followed by the respiratory and urinary isolates (61.54% and 46.94%, respectively). Conclusions: This study sought to provide useful data on the antifungal susceptibility of C. tropicalis isolates from ICU patients suffering from invasive infections with an increased trend towards elevated MICs levels of both fluconazole and voriconazole. Due to the high incidence of systemic candidiasis and antifungal resistance, C. tropicalis is emerging as a serious root of infections. Therefore, early and accurate identification of Candida species along with susceptibility testing is of utmost importance.

scholarly journals Non-albicans CandidaInfection: An Emerging Threat

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Sachin C. Deorukhkar ◽  
Santosh Saini ◽  
Stephen Mathew
Keyword(s):  
Candida Albicans ◽  
Virulence Factors ◽  
High Resistance ◽  
Fungal Pathogens ◽  
Antifungal Agents ◽  
Antifungal Susceptibility ◽  
Clinical Specimen ◽  
Antifungal Drugs ◽  
Clinical Specimens ◽  
The Past

The very nature of infectious diseases has undergone profound changes in the past few decades. Fungi once considered as nonpathogenic or less virulent are now recognized as a primary cause of morbidity and mortality in immunocompromised and severely ill patients.Candidaspp. are among the most common fungal pathogens.Candida albicanswas the predominant cause of candidiasis. However, a shift toward non-albicans Candidaspecies has been recently observed. These non-albicans Candidaspecies demonstrate reduced susceptibility to commonly used antifungal drugs. In the present study, we investigated the prevalence of non-albicans Candidaspp. amongCandidaisolates from various clinical specimens and analysed their virulence factors and antifungal susceptibility profile. A total of 523Candidaspp. were isolated from various clinical specimens. Non-albicans Candidaspecies were the predominant pathogens isolated. Non-albicans Candidaspecies also demonstrated the production of virulence factors once attributed toCandida albicans. Non-albicans Candidademonstrated high resistance to azole group of antifungal agents. Therefore, it can be concluded that non-albicans Candidaspecies have emerged as an important cause of infections. Their isolation from clinical specimen can no longer be ignored as a nonpathogenic isolate nor can it be dismissed as a contaminant.

scholarly journals Investigation of the relationship between virulence factors and genotype of Candida spp. isolated from blood cultures

2015 ◽  
Vol 9 (08) ◽  
pp. 857-864 ◽  
Author(s):  
Fatma Mutlu Sariguzel ◽  
Elife Berk ◽  
Ayse Nedret Koc ◽  
Hafize Sav ◽  
Gonca Demir
Keyword(s):  
Virulence Factors ◽  
Biofilm Formation ◽  
Blood Cultures ◽  
Chain Reaction ◽  
Candida Spp ◽  
Predominant Genotype ◽  
Microbiological Methods ◽  
Polymerase Chain ◽  
Esterase Production ◽  
The Relationship

Introduction: The aim of study was to investigate the virulence factors of phospholipase, proteinase, esterase production and biofilm formation in Candida species isolated from patients with candidemia, and to assess their relationship with Candida genotypes derived after repetitive sequence-based polymerase chain reaction (rep-PCR) fingerprinting. Methodology: Fifty-two strains were identified to species level according to conventional methods and sequencing. The DiversiLab system was used for the genotyping. Enzyme activities and biofilm formation were evaluated using microbiological methods. Results: The 52 strains were identified as follows: 29 C. parapsilosis, 19 C. albicans, 2 C. glabrata, and 2 C. tropicalis. Phospholipase and proteinase activities were observed to have statistically significant differences between C. albicans and non-albicans Candida (NAC) strains (p < 0.05), with C. albicans strains showing higher virulence. Rep-PCR revealed eight major genotypes (A-H).The 19 C. albicans and the 33 non-albicans Candida isolates yielded seven (A-G) and four (A, B, C, H) genotypes, respectively. C. albicans strains were not shown to have a predominant genotype and showed higher phospholipase and proteinase activitiy than did NAC, regardless of genotype. Genotype H (52%) was the predominant genotype for the NAC including 27 C. parapsilosis strains, but the majority of strains showed low virulence. Conclusions: NAC species were the most common causative agent for candidemia. Genotyping showed low transmission of C. albicans strains, but transmission of C. parapsilosis was high. In candidemia, several Candida virulence factors may be responsible at the same time. However, different genotypes of Candida strains showed different virulence activity.

Virulence Factors Associated with Quinolone Resistance in Proteus Species Isolated from Patients with Urinary Tract Infection

2021 ◽  
Vol 30 (1) ◽  
pp. 115-123
Author(s):  
Samah S. El-Kazzaz ◽  
Noha M. Mahmoud
Keyword(s):  
Urinary Tract ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Biofilm Formation ◽  
Quinolone Resistance ◽  
Protease Production ◽  
Causative Organism ◽  
Haemolytic Activity ◽  
Antibiotic Resistant ◽  
Tract Infections

Background: Proteus is an important causative organism of urinary system infections. The invasive nature of Proteus is supported by expression of multiple virulence factors; the infection outcome gets worse when those virulent isolates acquire antibiotic resistant determinants. Objectives: The present study was aiming at isolation of Proteus from urine of patients with urinary tract infections (UTIs) and to assess the relation between virulence factors expression and presence of quinolones resistance genes in those isolates. Methodology: Quinolone resistant Proteus isolates were chosen for detection of quinolone resistance genes, also they were tested for presence of different virulence factors. Results: Sixty eight quinolone resistant Proteus isolates were determined. aac(6′)- Ib-cr was the most frequently detected quinolone resistance gene. Haemagglutination, haemolytic activity, protease production and biofilm formation were documented in 79.4%, 76.5%, 70.6% and 83.8% of the isolates respectively. Conclusion: Proteus isolated from urine displayed many virulence factors and harbored a variety of quinolone resistance genes.

scholarly journals Virulence factors and ability of staphylococci from bovine milk and the cowshed environment to biofilm formation

2013 ◽  
Vol 16 (4) ◽  
pp. 639-645 ◽  
Author(s):  
B. Kot ◽  
T. Binek ◽  
M. Piechota ◽  
K.M. Wolska ◽  
E. Zdunek ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Significant Relationship ◽  
Biofilm Formation ◽  
Bovine Milk ◽  
Haemolytic Activity ◽  
The Difference

AbstractThe aim of this study was to examine virulence factors and the ability of S. aureus and CNS species isolated from milk of cows with mastitis to form biofilm, and to compare them with virulence factors of staphylococci from milk of cows without mastitis and cowshed environment. Most of S. aureus strains from cows with mastitis showed haemolytic activity (93.9%), among them 72.7% and 21.2% produced α- and β-haemolysin, respectively. S. aureus from cows with mastitis symptoms produced proteases (above 48%) and esterase (42.4%). The highly significant relationship between the number of S. xylosus strains producing haemolysins (62%) and the origin of these strains from milk of cows with mastitis was observed. The ability to produce proteases was significantly associated with S. sciuri from milk of cows with mastitis. The ability of biofilm formation by staphylococcal strains from milk of cows with mastitis was greater than in strains from milk of cows without mastitis and the difference was significant (p≤0.05). The highest percentage of strains from milk of cows with mastitis were weak biofilm formers (48.6%), while 40% and 11.4% of strains were moderate and strong biofilm producers, respectively. S. xylosus showed the highest ability to form biofilm, while the lowest ability to form biofilm was observed in S. aureus and S. epidermidis.In conclusion, production of exotoxins and enzymes, and ability of biofilm formation shown by many CNS isolated from milk of cows with mastitis symptoms indicates that these features are important in pathogenesis of this disease.

Distribution and Antifungal Susceptibility of Candida Species Causing Candidemia in China: An Update From the CHIF-NET Study

2020 ◽  
Vol 221 (Supplement_2) ◽  
pp. S139-S147 ◽  
Author(s):  
Meng Xiao ◽  
Sharon C-A Chen ◽  
Fanrong Kong ◽  
Xiu-Li Xu ◽  
Li Yan ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Candida Species ◽  
Antifungal Agents ◽  
Antifungal Susceptibility ◽  
Common Species ◽  
Sensu Stricto ◽  
Resistance Rate ◽  
Fluconazole Resistance ◽  
Microdilution Method ◽  
Broth Microdilution Method

Abstract Background Candidemia is the most common, serious fungal infection and Candida antifungal resistance is a challenge. We report recent surveillance of candidemia in China. Methods The study encompassed 77 Chinese hospitals over 3 years. Identification of Candida species was by mass spectrometry and DNA sequencing. Antifungal susceptibility was determined using the Clinical and Laboratory Standards Institute broth microdilution method. Results In total, 4010 isolates were collected from candidemia patients. Although C. albicans was the most common species, non-albicans Candida species accounted for over two-thirds of isolates, predominated C. parapsilosis complex (27.1%), C. tropicalis (18.7%), and C. glabrata complex (12.0%). Most C. albicans and C. parapsilosis complex isolates were susceptible to all antifungal agents (resistance rate &lt;5%). However, there was a decrease in voriconazole susceptibility to C. glabrata sensu stricto over the 3 years and fluconazole resistance rate in C. tropicalis tripled. Amongst less common Candida species, over one-third of C. pelliculosa isolates were coresistant to fluconazole and 5-flucytocine, and &gt;56% of C. haemulonii isolates were multidrug resistance. Conclusions Non-albicans Candida species are the predominant cause of candidemia in China. Azole resistance is notable amongst C. tropicalis and C. glabrata. Coresistance and multidrug resistance has emerged in less common Candida species.

scholarly journals Effects of changes in culture conditions on the virulence and antifungal susceptibility of dairy cow mastitis fungal isolates

2020 ◽  
Author(s):  
Yuan Yue ◽  
Shengyan Ma ◽  
Xiaoyu Wang ◽  
Xuezhang Zhou
Keyword(s):  
Virulence Factors ◽  
Dairy Cow ◽  
Antibacterial Agents ◽  
Antifungal Susceptibility ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Phospholipase Activity ◽  
Candida Spp ◽  
In Vitro Susceptibility

Abstract Background: In recent years, the number of incidences of dairy cow mastitis caused by non-albicans Candida (NAC) have increased owing to the virulence factors, including cell surface hydrophobicity (CSH) and phospholipase activity, of the causative agents, namely, Candida krusei and Candida parasitica. Temperature and pH changes in the cow's udder after fungal infection and unreasonable medication can affect the antifungal susceptibility of Candida spp. and their expression of virulence factors. Methods: In this study, the effects of different temperatures and pH on the virulence of NAC strains were tested, and the in vitro susceptibility of the fungal strains to Cu2+ and antibacterial agents were examined. Besides, the changes in the virulence factors of Candida spp., including biphasicity, hemolytic activity, CSH, and phospholipase activity under these test conditions were investigated, and the internal relationship between these factors was analyzed. Results: The results showed that the virulence factors and antifungal susceptibility of Candida spp. could be altered through changes in various physiological conditions. Both temperature and pH were noted to be important factors affecting Candida growth, antifungal susceptibility, and expression of virulence factors. Cu2+ inhibited the growth and virulence factors expression of Candida spp., whereas antibacterial agents directly promoted the growth of Candida spp., making them resistant, which is one of the reasons for breast inflammation symptoms in cows. Conclusions: These results on virulence factors, antifungal susceptibility, and physiological characteristics of NAC provide a theoretical basis for understanding and treating dairy cow mastitis caused by NAC.

The effect of some chemical materials against virulence factors of Candida ssp isolated from UTI patients

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Fatima Abdul Hussein Mejbel
Keyword(s):  
Urinary Tract Infection ◽  
Urinary Tract ◽  
Tract Infection ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Germ Tube ◽  
Laboratory Culture ◽  
Candida Spp ◽  
Other Substances ◽  
Chemical Materials

 During the period from September 2016 to December 2017,135 urine samples were collected from urinary tract infection patients attending to AL-Zahraa Hospital in AL-Najaf Governorate. The present study was conducted to isolate and identify Candida spp. isolated from urinary tract infection patients by different methods including direct examination, laboratory culture, biochemical test and by modern techniques (Api Candida kit) and determine the virulence factors phenotypic to Candida spp which involved (biofilm formation,phospholipase and germ tube). The percentage of females to males was as following, female (84) 62.2 % (21) infected and male (51) 37.8% (1) infected with all age categories. The results in this study are explain that is some Candida spp. such as C. albicans, have high susceptible to eugenole follow by phenol and umbellulone. The efficiency of some chemical substances such as (eugenole,umbellulone, and phenol) was evaluated to inhibit the growth of Candida ssp as well as some virulence factors such as biofilm formation,germ tube and phospholipase,which were studied in this research. Statistically analysis results have been significance difference between the results of the substance concentrations and the concentrations of the different other substances.

Epidemiology and Antifungal Susceptibility in Patients with Candidemia in a University Hospital, Thailand

2020 ◽  
Vol 103 (10) ◽  
pp. 1048-1056
Keyword(s):  
Antifungal Susceptibility ◽  
Underlying Disease ◽  
Outcome Data ◽  
Adult Patients ◽  
Antifungal Treatment ◽  
University Hospital ◽  
Fluconazole Resistance ◽  
Fluconazole Therapy ◽  
Fluconazole Resistant ◽  
High Level

Background: Candidemia is the most common nosocomial invasive fungal infection that causes high mortality. Emergence of drug-resistant Candida is reported worldwide but there are few studies in Thailand. Objective: To determine the epidemiology, antifungal susceptibility of Candida, and outcomes among adult patients with candidemia. Materials and Methods: A prospective, observational study in adult patients with candidemia was conducted in 2015 at a university hospital. Demographic, microbiological, and outcome data were recorded. Results: Fifty-two patients with candidemia were identified, of whom 76.9% had an underlying disease and 69.2% had risks for candidemia. Sixty-four percent of candidemia patients contracted non-albicans Candida and 36% had Candida albicans. C. tropicalis was the most common non-albicans Candida species isolated (35%), followed by C. parapsilosis (19%), and C. glabrata (10%). Fluconazole resistance was found in 12.5% of C. albicans and in 11.1% of C. parapsilosis isolates. Reduced fluconazole susceptibility or high-level fluconazole resistance was found in 68.7% of C. tropicalis isolates. All except C. parapsilosis had excellent susceptibility to echinocandins. Seventy-three percent (38/52) of patients received antifungal treatment, of whom, 78.9% received empiric fluconazole therapy, and 89.7% were started on antifungal treatment 24 hours after the isolation of Candida. The overall mortality rate was 51.9%. Conclusion: Fluconazole-resistant Candida became more prevalent particularly in C. tropicalis, which was the predominant species among non-albicans Candida causing candidemia. Empiric treatment with either amphotericin B or echinocandins would be appropriate in high-risk patients with suspected candidemia. Trial registration: Thai Clinical Trials Registry, TCTR20150605001 Keywords: Candida, Fluconazole, Resistant, Thailand

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