Identification Of Candida Albicans Research Articles

Identification of Candida albicans and non-MRSA Staphylococcus aureus in free-living amoebae isolated from the hospital wards; an alarm for distribution of nosocomial infections via FLA

ABSTRACT Free-living amoebae (FLA) are isolated from the hospital environments and known as Trojan horses for medical essential microorganisms. This study aimed to investigate the prevalence and the presence of FLA and two critical agents of nosocomial infections, in the hospital wards. Sixty samples were collected from four communities and cultured onto non-nutrient agar (NNA). After total DNA extraction, FLA were characterized using PCR and sequencing. The presence of Candida albicans and Staphylococcus aureus was evaluated using real-time and conventional PCR, respectively. Acanthamoeba sp. was characterized in 30 (50%) samples. Two (6.6%) and one (3.3%) samples were positive for Vahlkampfiidae and Vermamoeba vermiformis, respectively . S. aureus was detected in 13 (43.3%) of samples, while none of them were positive for methicillin-resistant gene. C. albicans DNA was detected in one (3.3%) FLA-positive sample. The isolation of FLA from hospital suggests an essential role these eukaryotes in the inter-ward circulation of nosocomial infections.

Effect of denture base acrylic resin containing silver nanoparticles on Candida Albicans adhesion and its release in artificial saliva

Background Candida albicans was considered a main reason of precipitate formations and decomposition of acrylic denture base; so many trials were objected to resist this microbial action and prolong the shelf life of the formulated fitting base. Aim of the work The present study aimed to adopt a new mixture of the silver nanoparticles with the PMMA denture base to get a prolonged antimicrobial protection for the formed base against Candida albicans. Statement of problem Accumulation of Candida Albicans on fitting surface of poly methyl meth-acrylate (PMMA) denture base. Purpose To evaluate the effect of denture base acrylic resin containing silver Nanoparticles (Ag NP) on Candida Albicans adhesion and its release in artificial saliva. Materials and methods Sixty round disks with dimensions of 15 mm diameter and 3 mm thickness specimens were prepared for this research. Control group A: 10 specimens were prepared from pure PMMA. Experimental group B: 50 specimens were prepared from PMMA containing 5% of Ag NP. Isolation and identification of Candida Albicans were taken from oral cavity of 10 patients by swabbing. The Specimens were immersed in artificial saliva for 3, 6, and 9 months. Microbiological test was done for specimens of each group to detect Candida Albicans accumulation at the same interval period by measuring the inhibition zone created around the disks. Specimens were taken from the artificial saliva to evaluate silver release in it by using UV-Vis Spectrophotometer Instrument ‘SHIMADZO UV-310 PC. For Spectrophotometer 1.0 cm and/or 0.2 cm matched silica cells. The amount of accumulated silver released was calculated to detect its cytotoxic effect1. Results For control group A there was no inhibition zone for Candida growth around the specimens. While for group B with Ag NP the greatest antimicrobial effect was found at zero time then was decreased gradually with increasing the time till reaching zero effect after 9 months resembling the control group. The amount of Nano silver in artificial saliva after 3 months was found to be little then it was increased gradually with increasing time. Conclusion Adding Ag NP to PMMA denture base has antimicrobial effect against Candida Albicans for only 9 months; then there was no effect as silver was released in saliva. The amount of released silver was found to be with no cytotoxic effect.

Effect of antimicrobial photodynamic therapy using toluidine blue on dual-species biofilms of Candida albicans and Candida krusei

BackgroundAlthough Candida albicans is the most frequent etiological agent of candidiasis, it has been reported a sizable number of infections related to the non-albicans Candida (NAC) species, Candida krusei. In addition, dual biofilms (biofilms composed by two species) may easily occur in vivo, becoming even more challenging the treatment of an infection. The fungicide effect of Photodynamic Therapy (PDT), using toluidine blue O (TBO) on both C. albicans and C. krusei development has been demonstrated. Thus, the objective of this study was to investigate the effects of PDT on dual-species biofilms of Candida albicans and Candida krusei. MethodsThe effect of PDT was observed on the metabolic activity of mature dual-species biofilms of Candida albicans and Candida krusei by a metabolic assay based on the reduction of XTT (2,3-bis(2‑methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide sodium salt) assay and the identification of Candida albicans and Candida krusei was performed on CHROMagar Candida medium. Resultsit was observed a reduction of ∼30% in the metabolic activity of a mature biofilm treated with PDT, using 0.05 mg·mL−1 TBO and during biofilm formation a predominance of C. albicans on C. krusei was observed. The inhibition observed was related to reduction in the number of Colony Forming Units (CFU) of Candida albicans from 31.33 ± 3.7 to 17.0 ± 1.5. The number of CFU of C. krusei was not significantly modified. ConclusionsThese results demonstrated the efficiency of PDT in inhibiting the dual-species biofilms of Candida albicans and Candida krusei by reducing C. albicans development.

Isolation and identification of Candida albicans from clinical specimens received at tertiary care centre

Background &Method: The aim of this study is to study Isolation and identification of Candida albicans and non candida albicans species in all clinical specimens received at Tertiary Care Centre.A detail history was taken with demographic details. Patient’s hospital records were used to know the use of any antifungal agents and past medical conditions. Result: 23.3% of the patients of age group < 1 year, followed by (16.6%) 41-50 years of age group and 6.6% of patients are 61-70 years of age group. 56.6% were male patients and 43.3% were female.53.4 % were Candida albicans and 46.6% were non-albicans Candida spp. By using unpaired t test, P value- 0.041, which is less than 0.05, hence it is statistically significant. Conclusion: C. albicans remains the main species but increasing incidence of non albicans Candida spp. has also been reported, and their antifungal drug susceptibility among patients visiting our tertiary care hospital. An increase in the predisposing conditions in recent years has resulted in an increasing incidence of Candida infections. Among 3000 of total samples processed during the study period, 30 isolates were positive for Candida infection. So prevalence rate was 0.81%.

Diagnostic yield of calcofluor white in the identification of Candida albicans in oral squamous cell carcinoma.

Although oral cancer is multifactorial in origin only few had evaluated the diagnostic parameters for candidal infection in oral squamous cell carcinoma (OSCC). To compare and assess the accuracy of Calcofluor White (CFW) to that of conventional staining methods to identify the presence of candidal infection in OSCC. Archival collections of 43 OSCC were retrieved for this investigation. Standard staining protocol was followed for the index test (CFW) and reference standard (Periodic Acid Schiff). Two examiners were blinded for either one of the staining techniques. Diagnostic test evaluation and Kappa statistic was calculated using MedCalc software. The study comprised 37 males, six females, and their mean age at the time of presentation was 51 (range 23 to 75 years). The sensitivity and specificity of CFW was 75.8% (CI 57.7 to 88.9%) and 10.0% (CI 0.2 to 44.5%). While the positive predictive and negative predictive values were 63.1% (CI - 50.6-74.0%) and 67.0% (CI - 49.2-81.0%). Our results show minimal agreement with PAS with a Kappa score of 0.148 (95% CI = 0.39 to 0.09). Overall detection rate was similar for both the index test and reference standard although there was considerable number of intermediate test results. Sensitivity of CFW was comparable to that of earlier studies but specificity was low and the degree of concordance was 60.4%. Although CFW staining can come with high false positive they are a useful test for ruling out candida infection when the test result is negative.

Surface-enhanced infrared absorption spectroscopy for microorganisms discrimination on silver nanoparticle substrates

Extracting molecular level label-free information from complex biological processes for a range of purposes including disease diagnosis and microbial identification and discrimination is always a challenging task. This is mostly due to lack of a technique providing rich molecular information with a high spatial and temporal resolution properties. Two surface-enhanced vibrational spectroscopic (SEVS) techniques, surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption spectroscopy (SEIRAS), are recently attracting considerable attention to study biosystems at an interface since they can satisfy these requirements to a certain level by providing rich intrinsic molecular information from molecules and molecular systems in a close proximity of nanostructured noble metal surfaces. In this study, these two surface-enhanced vibrational spectroscopic techniques are comparatively evaluated for the discrimination and identification of Candida albicans (C. albicans), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by paying attention to the source of the observed spectral pattern. The citrate-reduced colloidal silver nanoparticles (AgNPs) were used as substrates. The results show that the SEIRAS provides very rich molecular information about the biomolecular species adsorbed onto AgNPs similar to the case of SERS. The discrimination power of SEIRAS is much improved compared to FTIR demonstrated by PCA analysis. This study suggests that SEIRAS can be a potential technique for microbial analysis.

Identification of Candida albicans using different culture media and its association in leukoplakia and oral squamous cell carcinoma.

Context:Candida, leukoplakia and oral squamous cell carcinoma.Aims:The aim of the present study has assessed the association of Candida albicans with normal control group, leukoplakia and oral squamous cell carcinoma lesions of the oral cavity by using cornmeal broth +5% milk and milk serum liquid culture media.Settings and Design:Thepresent study comprised of total 80 patients, which included, 30 patients of Leukoplakia, 30 patients of oral squamous cell carcinoma and normal control group comprised of 20 healthy individuals who were not having any relevant medical, dental and habit history.Subjects and Methods:Saliva and Biopsy was taken from clinically suspected leukoplakia and oral squamous cell carcinoma lesions for the confirmation of histopathological diagnosis. Saliva samples were inoculated for fungal growth in Sabouraud Dextrose Agar, and culture-positive samples had undergone for the germ tube test. Germ tube-positive samples were further taken for chlamydospore production in milk serum and cornmeal broth +5% milk media separately at 8 and 16 h.Statistical Analysis Used:Chi-square test, Fischer extract test.Results:In the normal control group, no fungus growth was found; however, leukoplakia and oral squamous cell carcinoma showed fungus growth with positive germ tube test and chlamydospore formation; the result also showed rapid and quantitatively more chlamydospore formation in cornmeal broth +5% milk in comparison to serum milk culture media. There was no growth of Candida in mild and moderate form of leukoplakia. Whereas in a severe form of leukoplakia, there was more quantitative chlamydospore growth in cornmeal broth +5% milk liquid media.Conclusions:In this study, we have tried to compare the efficacy of cornmeal broth +5% milk and milk serum for the identification of C. albicans. Both the culture media were able to promote the growth of chlamydospore in C. albicans. Among different grades of leukoplakia, the growth of C. albicans was seen in severe dysplastic patient only while mild and moderate dysplasia showed no Candidal growth.

Susceptibility of Fungi Infect Animals to Antimycotics in Alexandria City

The aim of the present study was the isolation and phenotypic identification of dermatophytes isolated from cats, dogs, and cattle, followed by an evaluation of their antifungal susceptibility to azole antifungal agents in addition to isolation and phenotypic identification of Candida albicans from canine otitis, Aspergillus fumigatus from feline otitis and evaluation of their antifungal susceptibility. Specimens from pet animals were collected from veterinary clinics and from rural areas for the specimens from cattle in Alexandria city, Egypt. One hundred and ninety-five clinical samples were collected from pet animals and cattle (from cats; 80 ear swabs, 20 hair and skin scraping, from dogs; 50 ear swabs,15 hair and skin scraping and from cattle 30 hair and skin scraping) for mycological examination and antimycotic sensitivity test by disk diffusion method. The results of this study revealed that most dermatophytes isolated from pet animals are Microsporum canis, Microsporum gypsum, Trichophyton mentagrophytes, and Trichophyton rubrum, while from cattle M.gypseum, T.mentagrophytes and T.rubrum. Antifungal sensitivity test on the isolated dermatophytes was nearly similar and showed high resistance to fluconazole. In canine otitis, C.albicans was resistance to fluconazole, ketoconazole and clotrimazole and susceptible to itraconazole and voriconazole. A.fumigatus was susceptible only to itraconazole ,voriconazole and clotrimazole and resistance to other azole agents . This study shows the importance of knowing the main causative agent in canine and feline otitis and dermatophytosis in domestic animals and performing antifungal sensitivity to help in assaying the most susceptible antifungal agents.

Identification of Candida albicans and Candida dubliniensis Species Isolated from Bronchoalveolar Lavage Samples Using Genotypic and Phenotypic Methods.

Background:Candida dubliniensis is a newly diagnosed species very similar to Candida albicans phenotypically and first discovered in the mouth of people with AIDS in 1995. Among the different phenotypic and genotypic methods, a cost-effective method should be selected which makes it possible to differentiate these similar species.Materials and Methods:Polymerase chain reaction (PCR)-restriction fragment length polymorphism with MspI enzyme and the Duplex-PCR method were done by DNA extraction using boiling. The sequencing of the amplified ribosomal region was used to confirm the C. dubliniensis species. Direct examination and colony count of the yeasts were applied for bronchoalveolar lavage (BAL) samples and the growth rate of the yeasts were studied at 45°C. To understand the ability formation of chlamydoconidia in yeast isolates, they were separately cultured on the sunflower seed agar, wheat flour agar, and corn meal agar media.Results:Fifty-nine (49.2%) yeast colonies were identified from the total of 120 BAL specimens. Twenty-nine isolated yeasts; including 17 (58.6%) of C. albicans/dubliniensis complex and 12 (41.4%) of nonalbicans isolates produced pseudohypha or blastoconidia in direct smear with a mean colony count of 42000 CFU/mL. C. albicans with the frequency of 15 (42.9%) were the most common isolated yeasts, whereas C. dubliniensis was identified in two nonHIV patients.Conclusion:Sequencing of the replicated gene fragment is the best method for identifying the yeasts, but the determination of the species by phenotypic methods such as the creation of chlamydoconidia in sunflower seeds agar and wheat flour agar media can be cost-effective, have sensitivity and acceptable quality.

Comparative study for identification of Candida albicans with germ tube test in human serum and plasma

Comparative study for identification of Candida albicans with germ tube test in human serum and plasma

EFFECT OF TISSUE CONDITIONER COMBINED WITH NYSTATIN ON GROWTH OF CANDIDA ALBICANS IN COMPLETE DENTURE WEARERS

Aim: this study aimed to evaluate the effect of incorporation of Nystatin antifungal with tissue conditioner applied to the maxillary complete denture on growth of Candida Albicans. Materials and methods: Fifteen completely edentulous patients were selected and conventional complete dentures were fabricated for each patient. Viscogel tissue conditioner was applied at denture delivery. Isolation and identification of Candida albicans were done using Agar core inhibition assay after two months from wearing the denture. Then, a new application of viscogel mixed with Nystatin antifungal was applied replacing the first one and after additional two months from wearing the denture, Isolation and identification of Candida albicans was done. Results: there was no significant difference was observed before and after application of Nystatin antifungal. Conclusion: tissue conditioner when mixed with Nystatin antifungal showed no marked effect on inhibition of Candida Albicans.

Evaluation of HiCrome differential agar for speciation of candida

Background: In recent years, non-albicans Candida (NAC) are being increasingly reported in many laboratories. There is a need to diagnose them early as some of the species are resistant to antifungals. We evaluated the utility of HiCrome agar for speciation of Candida in comparison to conventional methods. Materials and Methods: Ninety-six isolates of Candida were speciated by morphology on corn meal agar (CMA), sugar assimilation tests (SAT), and HiCrome agar. Sensitivity, specificity, and positive predictive and negative predictive values were obtained. Results: Sensitivity of HiCrome agar in identification of Candida albicans was 97.05%, C. tropicalis was 83.33%, C. glabrata 100%, and C. krusei 87.5%; and specificity was 98.07, 91.93, 92, and 92.30%, respectively. Conclusion: The present Candida differential agar is useful in identifying a few of the species. With further modifications this media may replace the need for conventional methods. The rapid availability of results and identification of species in mixed cultures is significant.

Comparative Evaluation of Oral Candida albicans Carriage in Children with and without Dental Caries: A Microbiological in vivo Study.

ABSTRACTAim: The aim of this study was to examine the presence of Candida albicans in extensive carious lesions before and after treatment of the carious lesions and to evaluate the carriage of Candida albicans in children with and without caries.Materials and methods: The study was conducted on 60 childrens who were divided into two groups: Experimental group (group 1) and controlled group (group 2). Each group was further divided into 3 subgroups according to the dentition as: Group A (Deciduous), group B (Mixed) and group C (Permanent). Swab samples for mycological studies were collected from the dorsum of the tongue, vestibular sulcus and peak of the palatal vault. All samples were cultured directly on SDA plate (Sabouraud's dextrose agar). Number of Candida colonies was determined by counting colony forming unit on SDA plates. Further identification of Candida albicans was done by germ-tube test and corn-meal agar.Result: Overall prevalence of Candida albicans carriage was significantly higher and mean value of Candida albicans CFU (colony forming unit) was remarkably higher in group 1 (experimental group) as compare to group 2 (control group). Significant reduction in the frequency and mean value of Candida albicans CFU/plate was seen in children after treatment of carious lesions.Conclusion: This study supports the active role of Candida species in dental caries. Hence, Candida albicans may play an important role as a risk factor for dental caries. It was also seen that the oral environment stabilization procedures were able to reduce Candida albicans counts. Thus, these procedures can be considered efficient in the reduction of caries risk.How to cite this article: Srivastava B, Bhatia HP, Chaudhary V, Aggarwal A, Singh AK, Gupta N. Comparative Evaluation of Oral Candida albicans Carriage in Children with and without Dental Caries: A Microbiological in vivo Study. Int J Clin Pediatr Dent 2012;5(2):108-112.

Prevalence of Candidiasis in the Women with Leucorrhoea Attended to Health Centers in Hamadan , 1996

Background: Genital tract infections are one of the most common causes of referring to obstetrics clinics. The most common agents of genitalia infection are yeast ( Candida ) and parasite ( Trichomonas ). Establishment of fungal and parasitic infections needs many factors such as social, cultural and hormonal factors. Methods: In order to determine candidial infection in the patients with leucorrhoea, this study carried out in Hamadan in the private clinics and public health centers in 1996. A total of 248 patients with abnormal vaginal discharge, genitalia pruritus, disuria and disparonia examined by vaginal cotton soab sampling and examination of specimens by direct wet smear for Candida and Trichomanos , and culture was done in Saburoud dextrose agar for yeast. The smears stained by Gram staining for identification of organism and grown samples examined by germ tube formation test for identification of Candida albicans . Data about some individual variables of subjects were collected using a questionnaire. Results: This study indicated, 76(30.6%) of patients had candidial infection by wet smear method, however, 116 (46.8%) were positive by culture in Saburoud medium. With germ tube formation test, 33(13.4%) had C. albicans . Anyone had not trichomonal infection by direct wet smear. This study suggested that, candidial infection is very high in this region, and this is the most common cause of attending patients with leucorrhoea in the obstetrics clinics. Also, there was not any relationship between candidial infection and pregnancy status, main compliance and other compliances. Conclusion: We suggested, culture method is more sensitive than direct wet smear in the diagnosis of vulvo-vaginal infections, particularly in candidiasis. Regarding to role of personal hygiene measures in preventing of candidiasis, health education for women in the reproductive age is recommended.

Identification of Candida albicans by using different culture medias and its association in potentially malignant and malignant lesions

Background and Objective:The present study evaluates the association of Candida albicans with normal control group, potentially malignant and malignant lesions of oral cavity by using two different liquid culture media.Materials and Methods:Saliva was collected and biopsy was taken only from those clinically suspected potentially malignant and malignant lesions for histopathological diagnosis. Saliva samples were inoculated for fungal growth in Sabouraud's dextrose agar and culture-positive samples had undergone for Germ tube test. Germ tube-positive samples were further taken for quantification of chlamydospore production in liquid media at 8 and 16 hours.Results:In normal control groups no fungus growth was found; however, potentially malignant and malignant cases showed fungus growth, positive germ tube test and chlamydospore formation. The result also showed rapid and quantitatively more chlamydospore formation in corn meal broth + 5% milk in comparison to serum milk culture media.Conclusion:The oral mucosa is compromised in potentially malignant lesions, it can be argued that this species may be involved in carcinogenesis by elaborating the nitrosamine compounds which either act directly on oral mucosa or interact with other chemical carcinogens to activate specific proto-oncogenes and thereby initiate oral neoplasia.

Performance of Chromogenic Candida Agar and CHROMagar Candida in recovery and presumptive identification of monofungal and polyfungal vaginal isolates

Chromogenic Candida agar (OCCA) is a novel medium facilitating isolation and identification of Candida albicans, C. tropicalis, and C. krusei, as well as indicating polyfungal population in clinical samples. We compare the performance of OCCA, to CHROMagar Candida (CAC) and Sabouraud chloramphenicol agar (SCA). Vaginal swab samples from 392 women were simultaneously inoculated onto three study media. A total of 161 (41.1%) were found to be positive for fungi of which 140 (87%) were monofungal, and 21 (13%) polyfungal. One-hundred and fifty-seven samples (97.5%) were positive on CAC, 156 (96.9%) on OCCA, 148 (91.9%) on SCA and 144 (89.4%) samples were positive on all three media. The yeasts were identified by conventional methods including germ tube test, microscopic morphology on cornmeal-Tween 80 agar, and the commercial API 20C AUX. The 182 isolates were C. albicans (n = 104), C. glabrata (n = 51), C. krusei (n = 7), C. tropicalis (n = 5), C. famata (n = 3), C. kefyr (n = 3), C. zeylanoides (n = 3), C. colliculosa (n = 2), and other species of Candida (n = 4). Among the 21 polyfungal populations, 20 (95.2%) were detected in OCCA, 14 (66.7%) in CAC, and 13 (61.9%) in CAC and OCCA (P <0.05). Most polyfungal populations (47.6%) yielded C. albicans + C. glabrata. The efficiency of both chromogenic media for C. albicans was >or=92.9% at 72 h. OCCA is more efficient and reliable for rapidly identifying C. albicans and polyfungal populations than CAC. However, CAC is more efficient for identifying C. krusei and C. tropicalis. A chromogenic agar with a higher isolation rate of yeasts and better detection of polyfungal populations than SCA, is suggested as a medium of first choice when available.

Culture and Identification of Candida Albicans from Vaginal Ulcer and Separation of Enolase on SDS-PAGE

Candida albicans were isolated from patients with clinical symptoms of vaginal ulcer. Culture test for vaginal swab andscrapings were conducted on Sabouraud’s dextrose broth and Sabouraud’s dextrose agar plate respectively. Hichromecandida agar culture was used for differential identification of Candida. Smears from vaginal scrapings were preparedfor gram staining. The suspected strain of Candida was inoculated on corn meal agar medium for chlamydosporeformation. The suspected strain of Candida was inoculated in human serum for germ tube formation. Carbohydrateassimilation and fermentation tests were also conducted. The selected Candida colony was inoculated in YEPD mediumfor subculture and the cultured organism was harvested. The organisms were homogenized, centrifuged and thesupernatant was filtered. The filtrate was extracted in chloroform. The extract was centrifuged and the aqueous phasewas dialyzed. The dialyzed crude enolase was subjected to SDS-PAGE. The Sabouraud’s dextrose broth inoculatedwith vaginal swab showed turbid growth. The scraping from vagina showed typical smooth creamy white colonies witha characteristic yeast odour on Sabouraud’s dextrose agar plate. On Hichrome candida agar the Candida growthappeared as glistening green colored. Gram stained smears from vaginal scraps showed appearance of fungus as yeast budding. On corn meal agar the suspected Candida growth showed the formation of large, highly refractive, thickwalled terminal chlamydospores. Germ tubes were seen as long tube like projections extending from the yeast cells onhuman serum inoculated with suspected strain of Candida. The carbohydrate assimilation tests were positive fordextrose, maltose, sucrose, galactose, xylose and trehalose, and negative for lactose, melibiose, ellobiose, inositol,reffinose and dulcitol. The carbohydrate fermentation tests showed positive for dextrose, maltose, galactose andtrehalose, and negative for sucrose and lactose. SDS-PAGE for enolase from C. albicans showed a single polypeptideband of around 46 – 48 kDa.

Specific identification ofCandida albicans andCandida dubliniensis by PCR using species-specific primers

The aim of our study was to evaluate the effectiveness of phenotyping and genotyping methods for the identification ofCandida albicans andCandida dubliniensis. Phenotyping methods used are colony colour on CHROMagar Candida medium, growth at 45°C, TTC (2,3,5-triphenyl-tetrazolium chloride) reduction, germ tube and chlamydospores formation, and API 20C AUX. We also usedC. albicans andC. dubliniensis specific primers for identification performed with genotyping methods. DNAs ofC. albicans reference strains, differentCandida species,Cryptococcus neoformans, mycelial fungi, bacterial strains and human DNA were used as a template in order to evaluate the specificity of the primers. These primers yielded a 175-base-pair product only whenC. albicans DNA exists; however when other DNAs (except two isolates that are phenotypically identified asC. dubliniensis andC. tropicalis) exist no product appeared. In another PCR assay conducted by usingC. albicans DNA andC. dubliniensis specific primers, no product was observed.Candida albicans andC. dubliniensis specific primers were designed by Mannarelli and Kurtzman. Detection limit ofC. albicans primers was found to be 19 pg chromosomal DNA. In order to verify phenotypical definition with PCR amplification,C. albicans andC. dubliniensis specific primers were exposed to PCR by using DNAs that belong to 25 phenotypically defined oralCandida isolates.

Rapid and Accurate Identification of Candida albicans Isolates by Use of PNA FISH Flow

We developed the simple, rapid (1 h), and accurate PNA FISH(Flow) method for the identification of Candida albicans. The method exploits unique in solution in situ hybridization conditions under which the cells are simultaneously fixed and hybridized. This method facilitates the accurate identification of clinical yeast isolates using two scoring techniques: flow cytometry and fluorescence microscopy.

Efficacy of Chromogenic Candida Agar for isolation and presumptive identification of pathogenic yeast species

Chromogenic Candida Agar is a novel differential culture medium that is claimed to facilitate isolation and identification of Candida albicans, Candida tropicalis and Candida krusei. The performance of this medium was evaluated for presumptive identification of 521 yeast strains, representing 23 different species, for detection of specimens containing yeast mixtures, and for direct isolation of yeast from blood cultures. All yeasts grew well on the medium following a 48-h incubation period at 37 degrees C, and distinctive colonies were produced by C. albicans, C. tropicalis, C. krusei, Candida guilliermondii, Saccharomyces cerevisiae, Trichosporon mucoides and Geotrichum capitatum. The sensitivity and specificity of the medium exceeded 99.4% for each of these species. The medium provided some indication of the presence of Candida dubliniensis and Candida pulcherrima, and allowed the identification of polyfungal samples in 89.4% of the yeast mixtures. Finally, direct isolation on the medium from blood cultures that were positive for yeast according to Gram's stain (n = 42) showed that the expected colour and morphology of each species were not altered in the presence of blood.