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1.
The main purpose of this study has been to determine the in vitro antifungal susceptibility of clinical isolates from HIV-infected or AIDS patients, depending on the presence of oral candidosis. The oral cavity of 307 HIV-infected or AIDS patients was examined and an oral swab was cultured on Sabouraud glucose agar and studied by conventional mycological methods. In vitro antifungal susceptibility to amphotericin B, nystatin, fluconazole, itraconazole and ketoconazole was tested by disk diffusion with Neo-Sensitabs tablets (Rosco Diagnostica, Dinamarca). One hundred and thirty five Candida albicans isolates (91 serotype A, 38 serotype B, three C. albicans variety stellatoidea and three untyped isolates), three Candida krusei and two Candida glabrata were obtained. All the isolates were susceptible to nystatin and amphotericin B. However, 7.9% isolates were resistant to fluconazole and 2.9% isolates were resistant to ketoconazole or itraconazole. Nearly all C. krusei and C. glabrata isolates, 31% patients with candidosis and 20% Candida-colonized patients showed decreased susceptibility to azoles. This study shows that polyenes had a great in vitro efficacy against clinical isolates from HIV-infected patients and that in vitro resistance to azoles is not as high as observed in other countries.  相似文献   

2.
We have conducted a longitudinal study over a 3-year period to address the point prevalence, microbiological characteristics and antifungal susceptibility patterns of yeast isolates colonizing or infecting the oral cavities of 111 HIV-infected (51 adults, 60 children) and 201 non HIV-infected (109 adults, 92 children) Mexican persons. Regarding the epidemiology of oral candidiasis, Candida albicans was the most frequent species isolated. Seventy-one out of 85 isolates from colonized persons were C. albicans (83.5%), 27 isolates of them were from HIV-infected children and 44 from non HIV-infected patients. Sixty-two isolates belonged to serotype A which was the most prevalent serotype of C. albicans. Non-albicans species (Candida glabrata, Candida tropicalis and Candida parapsilosis, and Saccharomyces cerevisiae) were isolated from 16.5% of colonized patients and from 38.5% patients with candidiasis or Candida-related lesions. There were nine episodes of infection or colonization by at least 2 different yeast species. In the case of HIV/AIDS patients, it was determined that yeast carriage was not associated with the number of CD4+ cells or the viral load, but HAART reduced the prevalence of oral candidiasis. Overall, most patients harbored strains in vitro susceptible to fluconazole, however 10.8% of the yeasts were resistant to one or more azole antifungal agents and 29% were intermediate susceptible to them. On the contrary, 5-fluorocytosine was very active against all isolates tested, and amphotericin B was active against 97.9% of them.  相似文献   

3.
Oropharyngeal candidiasis continues to be considered the most common opportunistic disease in Aids patients. This study was designed to investigate species distribution, serotype and antifungal susceptibility profile among Candida spp. isolated from the oral cavity of Aids patients recruited from six Brazilian university centers. Oral swabs from 130 Aids patients were plated onto CHROMagar Candida medium and 142 isolates were recovered. Yeast isolates were identified by classical methods and serotyped using the Candida Check or target system-Iatron. Antifungal susceptibility testing was performed according to the NCCLS microbroth assay. C. albicans was the most frequently isolated species (91%), and 70% of the isolates belonged to serotype A. We detected 12 episodes of co-infection (9%), including co-infection with both serotypes of C. albicans. Non-albicans species were isolated from 12 episodes, 50% of them exhibited DDS or resistance to azoles. Otherwise, only 8 out 130 isolates of C. albicans exhibited DDS or resistance to azoles. Brazilian Aids patients are infected mainly by C. albicans serotype A, most of them susceptible to all antifungal drugs.  相似文献   

4.
Twelve Spanish laboratories collected 325 yeast clinical isolates during a 30 day's period, among them 224 Candida albicans, 30 Candida glabrata, and 27 Candida parapsilosis. In vitro antifungal susceptibility to amphotericin B, ketoconazole, fluconazole and itraconazole was determined by an agar diffusion test (Neo-Sensitabs, Rosco, Denmark). All the isolates tested were susceptible in vitroto amphotericin B and nearly all (97.2%) to itraconazole. In vitrosusceptibility to fluconazole and ketoconazole was high (90.2% and 91.4% of isolates, respectively) but showed variations depending on the species tested. Resistance to fluconazole and ketoconazole was low in C. albicans (4% and 3%, respectively), but 30% of Candida guilliermondii and 36% of C. glabrata isolates were resistant to fluconazole. Ketoconazole resistance was observed in 40% of C. glabrata, and 17% of Candida tropicalis. Resistance to antifungal drugs is very low in Spain and it is related to non-C. albicans isolates.  相似文献   

5.
The aim of this study was to evaluate the use of one of the molecular typing methods such as PCR (polymerase chain reaction) following by RFLP (restriction fragment length polymorphism) analysis in the identification of Candida species and then to differentiate the identified azole susceptible and resistant Candida albicans strains by using AP-PCR (arbitrarily primed-polymerase chain reaction). The identification of Candida species by PCR and RFLP analysis was based on the size and primary structural variation of rDNA intergenic spacer regions (ITS). Forty-four clinical Candida isolates comprising 5 species were included to the study. The amplification products were digested individually with 3 different restriction enzymes: HaeIII, DdeI, and BfaI. All the isolates tested yielded the expected band patterns by PCR and RFLP analysis. The results obtained from this study demonstrate that Candida species can be differentiated as C. albicans and non-C. albicans strains only by using HaeIII restriction enzyme and BfaI maintains the differentiation of these non-C. albicans species. After identification Candida species with RFLP analysis, C. albicans strains were included to the AP-PCR test. By using AP-PCR, fluconazole susceptible and resistant strains were differentiated. Nine fluconazole susceptible and 24 fluconazole resistant C. albicans were included to the study. Fluconazole resistant strains had more bands when evaluating with the agarose gel electrophoresis but there were no specific discriminatory band patterns to warrant the differentiation of the resistance. The identification of Candida species with the amplification of intergenic spacer region and RFLP analysis is a practical, short, and a reliable method when comparing to the conventional time-consuming Candida species identification methods. The fluconazole susceptibility testing with AP-PCR seems to be a promising method but further studies must be performed for more specific results.  相似文献   

6.
Abstract Genetic diversity of 160 Candida albicans isolates from the oral cavity of 16 HIV-infected adults prior to antifungal treatment was assessed using multilocus enzyme electrophoresis (10 C. albicans colonies were randomly chosen from each specimen culture). 20 electrophoretic types were distinguished from the analysis of 21 enzyme loci (10 were polymorphic). Five patients (31%) were found to be colonized by 2 or 3 genetically distinct strains. Nevertheless, in these five cases, one strain predominated (from 7 to 9 of the 10 colonies). Some HIV + patients with oral candidiasis appear to be simultaneously infected with several genetically different C. albicans strains before antifungal treatment.  相似文献   

7.
目的调查分析临床致病口腔念珠菌菌种分布及对氟康唑、伊曲康唑、制霉菌素、5-氟胞嘧啶和酮康唑的药物敏感性,以提供临床用药依据。方法收集口腔真菌感染患者标本,常规涂片镜检、培养,对酵母样生长菌落用生物梅里埃公司API20AUX进行菌种鉴定。对其中的念珠菌进行药敏分析。结果共收集141例临床口腔真菌病标本,其中118株念珠菌中,白念珠菌87株(73.7%),热带念珠菌15株(12.7%),高里念珠菌6株(5.1%),光滑念珠菌4株,其他念珠菌6株。口腔念珠菌对氟康唑、伊曲康唑、制霉菌素、5-氟胞嘧啶和酮康唑的耐药率分别为5.1%、1.7%、0%、3.4%、5.1%。结论解放军324医院口腔真菌感染主要为长期应用抗生素的老年患者。口腔念珠菌病仍以白念珠菌为主,对常用抗真菌药物呈不同程度的耐药,应进行真菌常规菌种鉴定及药敏试验。  相似文献   

8.
Oropharyngeal candidiasis (OPC) remains a common opportunistic infection in HIV-infected patients. Candida albicans is the most frequent causative agent of OPC. However, non-albicans spp. are being increasingly isolated. Candidal cell wall proteins and mannoproteins play important roles in the biology and patogenesis of candidiasis. In the present study, we have analyzed the proteinaceous components associated with cell wall extracts from C. albicans, Candida tropicalis, Candida pseudotropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, Candida guilliermondii and Candida rugosa obtained from HIV-infected patients with recurrent OPC. Cell wall proteinaceous components were extracted with beta-mercaptoethanol and analyzed using electrophoresis, immunoblotting (with antisera generated against C. albicans cell wall components, and with serum samples and oral saline rinses from patients with OPC), and lectin-blotting (concanavalin A) techniques. Numerous molecular species were solubilized from the various isolates. Major qualitative and quantitative differences in the polypeptidic and antigenic profiles associated with the cell wall extracts from the different Candida spp. were discernible. Some of the antibody preparations generated against C. albicans cell wall components were able to recognize homologous materials present in the extracts from non-albicans spp. Information on cell wall antigens of Candida species may be important in the therapy and prevention of HIV-related OPC.  相似文献   

9.
A clinical survey was carried out in seven cities in the southern part of Nigeria to determine the relative distribution of genitourinary Candida species in symptomatic patients reporting for diagnosis and treatment. Seven Candida species were identified using the CHROMagar Candida method and the API 20C System. Candida species were represented by Candida glabrata (33.7%), Candida albicans (20.1%), Candida tropicalis (18%), Candida guilliermondii (17.8%) Candida pseudotropicalis (5%), Candida parapsilosis (5%), and C. albicans var.stellatoidea (1.2%). The distribution of these species among the various age groups (15-20, 21-25, 26-30, 31-35, 36-40 and 41 plus years) was statistically insignificant. Out of the 517 positive samples, 182 (35%) were found in the age group 26-30 years, while age 41 plus had the lowest frequency (1.2%). The results presented show that C. albicans, usually reported to be the most frequently isolated species, is not the main species in the cities studied. With C. glabrata in preponderance, the finding supports recent studies reporting that several pathogenic non-C. albicans species are now being frequently isolated. The level of social activities, such as drug abuse and sexual promiscuity, may be important in the distribution frequency of Candida species in different age groups and locations.  相似文献   

10.
We investigated the presence of Candida dubliniensis among isolates previously identified as Candida albicans and maintained in a yeast stock collection from 1994 to 2000. All isolates were serotyped and further evaluated for antifungal susceptibility profile. After doing a screening test for C. dubliniensis isolates based on the capability of colonies to grow at 42 C, its final identification was obtained by randomly amplified polymorphic DNA (RAPD) analysis using three different primers. A total of 46 out of 548 screened isolates did not exhibit growth at 42 C and were further genotyped by RAPD. Eleven isolates were identified as C. dubliniensis with RAPD analysis. Regarding serotypes, 81.5% of C. albicans and all C. dubliniensis isolates belonged to serotype A. Of note, 9 out of 11 C. dubliniensis isolates were obtained from patients with acquired immunodeficiency syndrome (Aids) and all of them were susceptible to azoles and amphotericin B. We found 17 (3%) C. albicans isolates that were dose-dependent susceptibility or resistant to azoles. In conclusion, we found a low rate of C. dubliniensis isolates among stock cultures of yeasts previously identified as C. albicans. Most of these isolates were recovered from oral samples of Aids patients and exhibited high susceptibility to amphotericin B and azoles. C. albicans serotype A susceptible to all antifungal drugs is the major phenotype found in our stock culture.  相似文献   

11.
Candida species are a normal commensal present in a large percentage of healthy individuals. Denture wearers are predisposed to the development of candidosis and to the presence of Candida spp. The presence of the yeast, even in healthy subjects, should be considered more carefully. We investigated the prevalence of Candida spp. in 112 denture wearers and 103 individuals with natural teeth, patients from the clinic of total prosthesis of the Dental School of the Federal University of Minas Gerais, Brazil, and from the School of Pharmacy and Dentistry of Alfenas, Brazil. Factors like gender, age over 60 years, low education, and xerostomia were directly associated with the presence of Candida yeasts at a significance level of 5% (p > 0.05). However, the major predisposing factor for the carrier state was wearing dentures (p = 0.001). Candida isolates were identified using morphological and biochemical profiles. Seventy-one isolates were identified as C. albicans (65.1%), 15 as C. glabrata (13.7%), 8 as C. parapsilosis (7.3%), 3 as C. krusei (2.7%), and 12 as C. tropicalis (11.0%). Susceptibility testing to fluconazole and itraconazole was also performed with the strains obtained. Both drugs showed a strong inhibition against most oral isolates.  相似文献   

12.
The aim of this study was to assess species distribution, antifungal susceptibility and clonal relationships among Candida strains isolated from a group of pediatric/neonatal intensive care (PICU/NICU) patients that had a very high mortality rate (76%). The cases of 21 patients (19 with candidemia, 2 with Candida meningitides) treated over a 1-year period in a Turkish hospital PICU and NICU were retrospectively analyzed. Twenty-eight Candida isolates were detected from blood (20), cerebrospinal fluid (CSF) (2) and other specimens (6). Candida species were identified using the API ID 32C System. Susceptibility testing was done (all 28 isolates) for amphotericin B, fluconazole and itraconazole using the broth microdilution method. Arbitrarily primed polymerase chain reaction (AP-PCR) was used for molecular typing of the 3 most common ones; C. albicans (15), C. parapsilosis (6), and C. pelliculosa (4). Electrophoretic karyotyping (EK) was done to check clonal identity obtained by AP-PCR. Of the 20 blood isolates, 8 (40%) were C. albicans, 12 (60%) were non-albicans Candida, and one of the 2 CSF isolates was C. albicans. The overall species distribution was as follows: 15 C. albicans isolates, 6 C. parapsilosis isolates, 4 C. pelliculosa isolates, 2 C. famata isolates and 1 C tropicalis isolate. Amphotericin B had the best antifungal activity with a MIC90 of 0.125 microg/ml, and the rates of susceptibility to fluconazole and itraconazole were 93% and 82%, respectively. AP-PCR revealed 11 genotypes (4 were identical pairs, 7 were distinct) among the 15 C. albicans isolates, 2 genotypes (5 were classified in the same type) among the 6 C. parapsilosis isolates, and 4 separate genotypes for the 4 C. pelliculosa isolates. Karyotyping results correlated well with the AP-PCR findings. As indicated in the previous research, our results confirmed that non-albicans Candida species have become more frequently causative agents for invasive fungal infections in the ICU. Transmission of C. albicans and C. pelliculosa was relatively low, but transmission of C. parapsilosis was high, suggesting that more effective control and very strict treatment protocols are needed for patients having high mortality and invasive fungal infection in ICU.  相似文献   

13.
Ng  K. P. 《Mycopathologia》1998,144(3):135-140
The distribution of Candida species was examined using 1114 yeasts isolated from various clinical specimens. The isolates were identified by germ tube test, hyphal/pseudohyphae and chlamydoconidia production and carbohydrate assimilation test using ten carbohydrates (glucose, sucrose, trehalose, cellobiose, arabinose, galactose, mannitol, raffinose, lactose and maltose). Among the 1114 isolates studied, 9 species of Candida were identified and the relative frequency of isolation was C. albicans (44.2%), C. parapsilosis (26.0%), C. tropicalis (17.7%), C. glabrata (9.6%), C. krusei (1.2%), C. rugosa (0.6%), C. guilliermondii (0.2%), C. lusitaniae (0.08%) and C. kefyr (0.08%). Non- C. albicans was the most common Candida species isolated from blood, respiratory system, urine and skin. The isolate from vaginal swabs was predominantly C. albicans. 82.2% of C. glabrata and 64.2% of C. krusei isolated in this study were from vaginal swabs. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

14.
This study evaluated the phenotypic tests used to differentiate Candida albicans from Candida dubliniensis. A total of 55 isolates from vaginal secretions, oral cavity and hemoculture were studied. They were originally identified as C. albicans, based on their morphological and physiological characteristics. These isolates were tested for colony color development on CHROMagar Candida medium, growth at 45 degrees C on Sabouraud Dextrose agar, lipolytic activity on Tween 80 Agar medium and colony morphology and chlamydoconidia formation on Staib agar medium. Of the 55 isolates studied, seven yielded one or more phenotypic characteristics suggestive of Candida dubliniensis. These isolates were tested by PCR with specific primers for Candida dubliniensis and API ID 32. The seven isolates were confirmed as Candida albicans. All of these finding indicate that DNA based tests should be used for definitive identification of Candida dubliniensis.  相似文献   

15.
Candida species were detected and identified in samples from the buccal mucosa, dorsal surface of the tongue and supragingival plaque of subjects with oral lichen planus (OLP). The Candida in the samples were cultured on selection agars, and identified by sequence analyses of 18S, 5.8S and 25/28S rRNA. The isolation frequency of Candida was higher in subjects with OLP than in those with healthy oral mucosa. Non-C. albicans were only isolated from people with OLP. These results support the notion that subjects with OLP are more likely to have oral colonization with Candida, and that non-C. albicans are specifically present in subjects with this condition.  相似文献   

16.
A total of eighty-seven Candida albicans isolates from a group of Thai AIDS patients were characterized for phenotypic and genotypic profiles and antifungal susceptibility to ketoconazole. Phenotyping of the isolates was carried out by a biotyping method based on the enzyme profiles, carbohydrate assimilation patterns and boric acid resistance of the yeasts. Genotyping was performed through randomly amplified polymorphic DNA (RAPD) analysis. Antifungal susceptibility of ketoconazole was performed using the NCCLS broth microdilution method. Combination of the biotypic tests revealed a total of 49 different biotypes. The most predominant was A1S (31%), the remaining biotypes represented only few isolates in each. RAPD profiles identified 14 clusters of genotype among the 87 isolates. Almost every individual harboured his/her own specific isolate and in 25 of 26 (96.2%) harboured more than one clonal type. The heterogeneity of both phenotypic and genotypic profiles of C. albicans isolates in this study was similar to previous reports from other oral sources in different geographic areas. All isolates were susceptible to ketoconazole. The findings may be useful as baseline information of oral C. albicans colonization in Thai population living in the south of Thailand.  相似文献   

17.
The incidence of infections caused by Candida species (candidosis) has increased considerably over the past three decades, mainly due to the rise of the AIDS epidemic, an increasingly aged population, higher numbers of immunocompromised patients and the more widespread use of indwelling medical devices. Candida albicans is the main cause of candidosis; however, non-C. albicans Candida (NCAC) species such as Candida glabrata, Candida tropicalis and Candida parapsilosis are now frequently identified as human pathogens. The apparent increased emergence of these species as human pathogens can be attributed to improved identification methods and also associated with the degree of diseases of the patients, the interventions that they were subjected and the drugs used. Candida pathogenicity is facilitated by a number of virulence factors, most importantly adherence to host surfaces including medical devices, biofilm formation and secretion of hydrolytic enzymes (e.g. proteases, phospholipases and haemolysins). Furthermore, despite extensive research to identify pathogenic factors in fungi, particularly in C. albicans, relatively little is known about NCAC species. This review provides information on the current state of knowledge on the biology, identification, epidemiology, pathogenicity and antifungal resistance of C. glabrata, C. parapsilosis and C. tropicalis.  相似文献   

18.
The aim of this study was to determine the prevalence of primary resistance to 5-fluorocytosine (5FC) among clinical isolates of yeasts in Spain where this drug is not currently available for therapy. We have tested the in vitro activity of 5FC against 1,021 recent yeast clinical isolates, including 522 Candida albicans, 140 Candida parapsilosis, 68 Candida glabrata, 41 Candida dubliniensis, 50 Candida guilliermondii, 34 Candida tropicalis, 28 Candida krusei, 20 Candida famata, 11 Cryptococcus neoformans, 5 Cryptococcus albidus, 43 Rhodotorula spp., 24 Trichosporon spp., 5 Saccharomyces cerevisiae, 9 Pichia spp., and 21 isolates from other 11 yeast species. The MICs were determined by the ATB Fungus agar microdilution test (bioMerieux, France) and the following interpretive breakpoints were used: susceptible, > 4 microg/ml; intermediate, 8 to 16 microg/ml; resistant, > 32 microg/ml. 5FC was very active against Candida spp. and other medically important yeasts as 852 (83.4%) of the studied isolates were susceptible (MIC < 4 microg/ml). The species most susceptible to 5FC were C. dubliniensis (100%of isolates; MIC90, 0.25 microg/ml), C. famata (100% of isolates; MIC90, 0.25 microg/ml), C. guilliermondii (98%of isolates; MIC90, 0.25 microg/ml), C. glabrata (95.5% of isolates; MIC90, 0.25 microg/ml), and C. neoformans (90.9% of isolates; MIC90, 2 microg/ml). Primary resistance to 5FC was very uncommon, and a MIC > 32 microg/ml, indicator of in vitro resistance, was observed in 106 isolates (10.4%): 77 C. albicans (16.5% of isolates; MIC90, > 128 microg/ml), 9 C. parapsilosis (6.4% of isolates; MIC90, 8 microg/ml), 4 C. albidus (80% of isolates, MIC50, > 128 microg/ml), 3 C. glabrata (4.4% of isolates; MIC90, 0.25 microg/ml), 3 C. tropicalis (8.8% of isolates; MIC90, 4 microg/ml), 2 C. krusei (7.1% of isolates; MIC90, 8 microg/ml), 2 Rhodotorula spp. (4.6% of isolates, MIC90, 1 microg/ml), 8 Trichosporon spp. (33.3% of isolates; MIC90, 64 microg/ml), and 1 C. lipolytica (50% of isolates). Interestingly, most C. albicans (67 out of 77 isolates) resistant to 5FC were serotype B isolates.  相似文献   

19.
The opportunistic Candida species existing as part of commensal microbiota in humans are usually the etiological agents causing infections. We investigated whether isolates collected from different age groups, hospital units, and sources have distinct characteristics. A total of 913 isolates comprising 395 Candida albicans, 230 Candida tropicalis, 202 Candida glabrata, 62 Candida parapsilosis, 13 Candida krusei, and 11 of other six species were analyzed. Urine was the most common source (41.2%), followed by sputum (16.3%), blood (15.2%), and others (27.3%). Candida albicans and C. parapsilosis were more prevalent in the working group [from 19 to 65 years], whereas C. tropicalis and C. glabrata were more prevalent in the elder one (≥ 66 years). We found that the age of patients and the source of isolates affect the distribution of species. On the other hand, the drug susceptibility of isolates was associated with fungal species and whether patients were hospitalized.  相似文献   

20.
The purpose of this work was to evaluate biochemical and serological methods to characterize and identify Candida species from the oral cavity. The strains used were five Candida species previously identified: C. albicans, C. guilliermondii, C. parapsilosis, C. krusei, C. tropicalis, and Kluyveromyces marxianus, as a negative control. The analyses were conducted through the SDS-PAGE associated with statistical analysis using software, chromogenic medium, and CHROMagar Candida (CA), as a differential medium for the isolation and presumptive identification of clinically important yeasts and an enzyme-linked immunoabsorbent assay (ELISA), using antisera produced against antigens from two C. albicans strains. This method enabled the screening of the three Candida species: C. albicans, C. tropicalis, and C. krusei, with 100% of specificity. The ELISA using purified immunoglobulin G showed a high level of cross-reaction against protein extracts of Candida species. The SDS-PAGE method allowed the clustering of species-specific isolates using the Simple Matching coefficient, S(SM) = 1.0. The protein profile analysis by SDS-PAGE increases what is known about the taxonomic relationships among oral yeasts. This methodology showed good reproducibility and allows collection of useful information for numerical analysis on information relevant to clinical application, and epidemiological and systematical studies.  相似文献   

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