Study of molecular epidemiology of candidiasis in portugal by PCR fingerprinting of Candida clinical isolates.
Ontology highlight
ABSTRACT:
SUBMITTER: Correia A
PROVIDER: S-EPMC535247 | biostudies-literature | 2004 Dec
REPOSITORIES: biostudies-literature
Publications
Study of molecular epidemiology of candidiasis in portugal by PCR fingerprinting of Candida clinical isolates.
Correia Alexandra A Sampaio Paula P Almeida Judite J Pais Célia C
Journal of clinical microbiology 20041201 12
PCR fingerprinting was used to type 177 yeast isolates obtained from two medical institutions. Candida albicans was the predominant species found, followed by C. tropicalis, C. glabrata, C. parapsilosis, C. guilliermondii, and C. krusei, which accounted for over 20% of the strains isolated. This survey represents the first study of molecular epidemiology of candidiasis in Portugal. ...[more]
Similar Datasets
Project description:Oligonucleotide DNA microarrays were used as a platform to compare C. jejuni isolates from feedlot cattle and human clinical cases from Alberta. Comparative genomic hybridization (CGH) analysis was performed on 87 isolates (46 bovine, 41 human) obtained within the same geographical regions and time frame. In addition, We also performed gene association analysis to determine if any genes may be differentially distributed between human and cattle sources or between clusters dominated by either human or cattle isolates (“human enriched” vs “cattle enriched”). Keywords: Comparative Genomic Hybridization; Genomic epidemiology; Gene-association study
2008-10-17 | GSE13228 | GEO
Project description:A repetitive sequence-based PCR (rep-PCR) technique was developed to characterize the genotypic relatedness among Candida rugosa isolates. Two repetitive sequences, viz., Care-2 and Com29 from Candida albicans, were used to design primers Ca-21, Ca-22, and Com-21, respectively. When used alone or in combination, these primers generated discriminatory fingerprints by amplifying the adjacent variable regions of the genome. Twenty-three isolates from burn patients, eight from other human sources, and four C. rugosa isolates pathogenic in animals were placed into nine fingerprinting groups. Different primers placed these isolates into identical groups, indicating that rep-PCR is a specific and reproducible technique for molecular characterization of C. rugosa. Moreover, these primers unequivocally discriminated among other important Candida species such as C. albicans, C. glabrata, C. tropicalis, C. krusei, C. parapsilosis, C. kefyr, and C. lusitaniae. These data confirm the conservation of repetitive sequences in Candida species. Because of its ease and sensitivity, rep-PCR offers a relatively rapid and discriminatory method for molecular typing of C. rugosa in outbreaks.
| S-EPMC229093 | biostudies-other
Project description:Candida glabrata readily develops resistance to echinocandins. Identification, antifungal susceptibility testing (AST) and resistance mechanism to echinocandins among C. glabrata was determined in Kuwait. C. glabrata isolates (n = 75) were tested by Vitek2, multiplex PCR and/or PCR-sequencing of rDNA. AST to fluconazole, caspofungin, micafungin and amphotericin B was determined by Etest and to micafungin by broth microdilution (BMD). Mutations in hotspot-1/hotspot-2 of FKS1/FKS2 and ERG11 were detected by PCR-sequencing. All isolates were identified as C. glabrata sensu stricto. Seventy isolates were susceptible and five were resistant to micafungin by Etest and BMD (essential agreement, 93%; categorical agreement, 100%). Three micafungin-resistant isolates were resistant and two were susceptible dose-dependent to caspofungin. Four and one micafungin-resistant isolate contained S663P and ∆659 F mutation, respectively, in hotspot-1 of FKS2. Micafungin-resistant isolates were genotypically distinct strains. Only one of 36 fluconazole-resistant isolate contained nonsynonymous ERG11 mutations. Thirty-four of 36 fluconazole-resistant isolates were genotypically distinct strains. Our data show that micafungin susceptibility reliably identifies echinocandin-resistant isolates and may serve as a surrogate marker for predicting susceptibility/resistance of C. glabrata to caspofungin. All micafungin-resistant isolates also harbored a nonsynonymous/deletion mutation in hotspot-1 of FKS2. Fingerprinting data showed that echinocandin/fluconazole resistance development in C. glabrata is not clonal.
| S-EPMC7148369 | biostudies-literature
Project description:Candida dubliniensis is a newly identified species of Candida that is phenotypically similar to but genetically distinct from C. albicans. This organism has been recovered with increasing frequency from the oral cavities of human immunodeficiency virus (HIV)-infected and AIDS patients and has been implicated as a causative agent of oral candidiasis and systemic disease. In the present study we characterized the molecular mechanisms of resistance to fluconazole (FLC) in C. dubliniensis clinical isolates from two different HIV-infected patients with oropharyngeal candidiasis. Isolates were identified to the species level by phenotypic and genotypic tests. DNA-typing techniques were used to assess strain identity. Antifungal susceptibility testing was performed by NCCLS techniques. Northern blotting analysis was used to monitor the expression of genes encoding lanosterol demethylase (ERG11) and efflux transporters (CDR and MDR1) in matched sets of C. dubliniensis-susceptible and -resistant isolates by using probes generated from their homologous C. albicans sequences. In addition, ERG11 genes were amplified by PCR, and their nucleotide sequences were determined in order to detect point mutations with a possible effect in the affinity for azoles. Decreasing susceptibilities to FLC were detected in C. dubliniensis isolates recovered from both patients during the course of treatment. FLC-resistant C. dubliniensis isolates from one patient demonstrated combined upregulation of the MDR1, CDR1, and ERG11 genes. Among the isolates from the second patient, all isolates showing decreased susceptibility to FLC demonstrated upregulation of MDR1, whereas the levels of mRNA for the ERG11 genes remained constant and the expression of CDR genes was negligible. Fourteen point mutations were found in the ERG11 genes of the isolates with decreased susceptibility to FLC. These data demonstrate that the development of azole resistance in C. dublinensis clinical isolates from HIV-infected patients treated with FLC is mediated by multiple molecular mechanisms of resistance, similar to the observations found in the case of C. albicans.
| S-EPMC127221 | biostudies-literature
Project description:Chronic mucocutaneous candidiasis (CMC) is a primary immunodeficiency disorder characterised by susceptibility to chronic Candida and fungal dermatophyte infections of the skin, nails and mucous membranes. Molecular epidemiology studies of CMC infection are limited in number and scope and it is not clear whether single or multiple strains inducing CMC persist stably or are exchanged and replaced. We subjected 42 C. albicans individual single colony isolates from 6 unrelated CMC patients to multilocus sequence typing (MLST). Multiple colonies were typed from swabs taken from multiple body sites across multiple time points over a 17-month period. Among isolates from each individual patient, our data show clonal and persistent diploid sequence types (DSTs) that were stable over time, identical between multiple infection sites and exhibit azole resistant phenotypes. No shared origin or common source of infection was identified among isolates from these patients. Additionally, we performed C. albicans MLST SNP genotype frequency analysis to identify signatures of past loss of heterozygosity (LOH) events among persistent and azole resistant isolates retrieved from patients with autoimmune disorders including CMC.
| S-EPMC4743940 | biostudies-literature
Project description:A total of 244 Candida albicans isolates recovered from vulvovaginal candidiasis (VVC) patients in Suzhou, Eastern China, were investigated. According to CLSI documents M27-A4 and M59-3ed/M60-2ed, the MIC geometric means of nine antifungals in increasing order were micafungin (0.048 mg/L), anidulafungin (0.132 mg/L), caspofungin (0.19 mg/L), itraconazole (0.23 mg/L), posaconazole (0.25 mg/L), voriconazole (0.28 mg/L), 5-flucytosine (0.44 mg/L), amphotericin B (0.49 mg/L) and fluconazole (2.01 mg/L) respectively. Of note, 6.5% (16/244) C. albicans isolates showed resistance mainly to anidulafungin (mono-echinocandin resistance), while voriconazole had the lowest susceptibility rate of 34.8% (85/244), followed by fluconazole 59.4% (145/244), respectively. All isolates were genotyped by allelic combination of 3 microsatellite markers (CEF3, CAIII and LOC4). A total of 129 different allelic genotypes were identified, in which seven different clades were recognized with a discriminatory power of 0.96. Genotypes A-D were present in 35% of the isolates. In conclusion, decrease in antifungal drug susceptibility to C. albicans isolates from VVC is alarming. Our findings revealed the genetic diversity of C. albicans isolates among VVC patients and provided insights into the molecular epidemiology of Candida infections in China.
| S-EPMC9124162 | biostudies-literature
Project description:Oligonucleotide DNA microarrays were used as a platform to compare C. jejuni isolates from feedlot cattle and human clinical cases from Alberta. Comparative genomic hybridization (CGH) analysis was performed on 87 isolates (46 bovine, 41 human) obtained within the same geographical regions and time frame. In addition, We also performed gene association analysis to determine if any genes may be differentially distributed between human and cattle sources or between clusters dominated by either human or cattle isolates (âhuman enrichedâ vs âcattle enrichedâ). Keywords: Comparative Genomic Hybridization; Genomic epidemiology; Gene-association study Data from 119 microarrays is included in the dataset, representing the 89 bacterial strains analyzed (87 field isolates, 2 control laboratory strains). Replicate arrays for 20 of the 87 field isolates were included in the dataset, as well as 5 replicates for each of the 2 laboratory controls. An array representing 1546 ORFs from strain NCTC 11168 was used in CGH experiments. CGH was performed by comparing signal from each Tester field isolate analyzed vs. signal from the Control strain NCTC 11168. Values represent mean of triplicate spots.
2010-05-18 | E-GEOD-13228 | biostudies-arrayexpress
Project description:ObjectiveInvasive candidiasis is a leading cause of infection-related morbidity and mortality in extremely low birth weight (<1000-g) infants. We quantified risk factors that predict infection in premature infants at high risk and compared clinical judgment with a prediction model of invasive candidiasis.MethodsThe study involved a prospective observational cohort of infants≤1000 g birth weight at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. At each sepsis evaluation, clinical information was recorded, cultures were obtained, and clinicians prospectively recorded their estimate of the probability of invasive candidiasis. Two models were generated with invasive candidiasis as their outcome: (1) potentially modifiable risk factors; and (2) a clinical model at time of blood culture to predict candidiasis.ResultsInvasive candidiasis occurred in 137 of 1515 (9.0%) infants and was documented by positive culture from ≥1 of these sources: blood (n=96); cerebrospinal fluid (n=9); urine obtained by catheterization (n=52); or other sterile body fluid (n=10). Mortality rate was not different for infants who had positive blood culture compared with those with isolated positive urine culture. Incidence of candida varied from 2% to 28% at the 13 centers that enrolled≥50 infants. Potentially modifiable risk factors included central catheter, broad-spectrum antibiotics (eg, third-generation cephalosporins), intravenous lipid emulsion, endotracheal tube, and antenatal antibiotics. The clinical prediction model had an area under the receiver operating characteristic curve of 0.79 and was superior to clinician judgment (0.70) in predicting subsequent invasive candidiasis.ConclusionPrevious antibiotics, presence of a central catheter or endotracheal tube, and center were strongly associated with invasive candidiasis. Modeling was more accurate in predicting invasive candidiasis than clinical judgment.
| S-EPMC3045840 | biostudies-literature
Project description:Molecular typing of Candida albicans is important for studying the population structure and epidemiology of this opportunistic yeast, such as population dynamics, nosocomial infections, multiple infections and microevolution. The genetic diversity of C. albicans has been rarely studied in China. In the present study, multilocus sequence typing (MLST) was used to characterize the genetic diversity and population structure of 62 C. albicans isolates collected from 40 patients from Huashan Hospital in Shanghai, China. A total of 50 diploid sequence types (DSTs) were identified in the 62 C. albicans isolates, with 41 newly identified DSTs. Based on cluster analysis, the 62 isolates were classified into nine existing clades and two new clades (namely clades New 1 and New 2). The majority of the isolates were clustered into three clades, clade 6 (37.5%), clade 1 (15.0%) and clade 17 (15.0%). Isolates of clade New 2 were specifically identified in East Asia. We identified three cases of potential nosocomial transmission based on association analysis between patients' clinical data and the genotypes of corresponding isolates. Finally, by analyzing the genotypes of serial isolates we further demonstrated that the microevolution of C. albicans was due to loss of heterozygosity. Our study represents the first molecular typing of C. albicans in eastern China, and we confirmed that MLST is a useful tool for studying the epidemiology and evolution of C. albicans.
| S-EPMC4412568 | biostudies-literature
Project description:Clonal expansion of fluconazole resistant (FLZ-R) Candida parapsilosis isolates is increasingly being identified in many countries, while there is no study exploring the antifungal susceptibility pattern, genetic diversity, and clinical information for Iranian C. parapsilosis blood isolates. Candida parapsilosis species complex blood isolates (n = 98) were recovered from nine hospitals located in three major cities, identified by MALDI-TOF MS, and their genetic relatedness was examined by AFLP fingerprinting. Antifungal susceptibility testing followed CLSI-M27-A3 and ERG11, MRR1 and hotspots 1/2 (HS1/2) of FKS1 were sequenced to assess the azole and echinocandin resistance mechanisms, respectively. Ninety-four C. parapsilosis and four Candida orthopsilosis isolates were identified from 90 patients. Only 43 patients received systemic antifungal drugs with fluconazole as the main antifungal used. The overall mortality rate was 46.6% (42/90) and death mostly occurred for those receiving systemic antifungals (25/43) relative to those not treated (17/47). Although, antifungal-resistance was rare, one isolate was multidrug-resistant (FLZ = 16 μg/ml and micafungin = 8 μg/ml) and the infected patient showed therapeutic failure to FLZ prophylaxis. Mutations causing azole and echinocandin resistance were not found in the genes studied. AFLP revealed five genotypes (G) and G1 was the main one (59/94; 62.7%). Clinical outcome was significantly associated with city (P = 0.02, α <0.05) and Mashhad was significantly associated with mortality (P = 0.03, α <0.05). Overall, we found a low level of antifungal resistance for Iranian C. parapsilosis blood isolates, but the noted MDR strain can potentially become the source of future infections and challenge the antifungal therapy in antifungal-naïve patients. AFLP typing results warrants confirmation using other resolutive typing methods.
| S-EPMC7253641 | biostudies-literature