1
|
Fang Y, Nie L, Wang S, Liu S, Li H, Yu R. A universal fluorescence biosensor based on rolling circle amplification and locking probe for DNA detection. Mikrochim Acta 2024; 191:437. [PMID: 38951284 DOI: 10.1007/s00604-024-06501-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 06/11/2024] [Indexed: 07/03/2024]
Abstract
A stable DNA signal amplification sensor was developed on account of rolling circle amplification (RCA). This sensor includes target DNA-controlled rolling circle amplification technology and locking probe DNA replacement technology, which can be used to detect DNA fragments with genetic information, thus constructing a biosensor for universal detection of DNA. This study takes the homologous DNA of human immunodeficiency virus (HIV) and let-7a as examples to describe this biosensor. The padlock probe is first cyclized by T4 DNA ligase in response to the target's reaction with it. Then, rolling cycle amplification is initiated by Phi29 DNA polymerase, resulting in the formation of a lengthy chain with several triggers. These triggers can open the locked probe LP1 with the fluorescence signal turned off, so that it can continue to react with H2 to form a stable H1-H2 double strand. This regulates the distance between B-DNA modified by the quenching group and H1 modified by fluorescent group, and the fluorescence signal is recovered.
Collapse
Affiliation(s)
- Ying Fang
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, P.R. China
| | - Lanxin Nie
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, P.R. China
| | - Suqin Wang
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, P.R. China
| | - Shiwen Liu
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, P.R. China.
- Jiangxi Provincial Center for Disease Control and Prevention, Nanchang, 330029, P. R. China.
| | - Hongbo Li
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, P.R. China.
| | - Ruqin Yu
- State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, P.R. China
| |
Collapse
|
2
|
Mendoza-Reyes DF, Gómez-Gaviria M, Mora-Montes HM. Candida lusitaniae: Biology, Pathogenicity, Virulence Factors, Diagnosis, and Treatment. Infect Drug Resist 2022; 15:5121-5135. [PMID: 36068831 PMCID: PMC9441179 DOI: 10.2147/idr.s383785] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/25/2022] [Indexed: 12/30/2022] Open
Abstract
The incidence of fungal infections is increasing at an alarming rate and has posed a great challenge for science in recent years. The rise in these infections has been related to the increase in immunocompromised patients and the resistance of different species to antifungal drugs. Infections caused by the different Candida species, especially Candida albicans, are one of the most common mycoses in humans, and the etiological agents are considered opportunistic pathogens associated with high mortality rates when disseminated infections occur. Candida lusitaniae is considered an emerging opportunistic pathogen that most frequently affects immunocompromised patients with some comorbidity. Although it is a low-frequency pathogen, and the mortality rate of C. lusitaniae-caused candidemia does not exceed 5%, some isolates are known to be resistant to antifungals such as amphotericin B, 5-fluorocytosine, and fluconazole. In this paper, a detailed review of the current literature on this organism and its different aspects, such as its biology, possible virulence factors, pathogen-host interaction, diagnosis, and treatment of infection, is provided. Of particular interest, through Blastp analysis we predicted possible virulence factors in this species.
Collapse
Affiliation(s)
- Diana F Mendoza-Reyes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
| | - Manuela Gómez-Gaviria
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
- Correspondence: Manuela Gómez-Gaviria; Héctor M Mora-Montes, Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, Guanajuato, Gto, C.P. 36050, México, Tel +52 473-7320006 Ext. 8193, Fax +52 473-7320006 Ext. 8153, Email ;
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
| |
Collapse
|
3
|
Maranhão FCDA, Mendonça NM, Teixeira TC, Lages GADCS, de Melo JA, Porciuncula CGG, da Silva Filho EA, Silva DMW. Molecular Identification of Candida Species in the Oral Microbiota of Individuals with Down Syndrome: A Case-Control Study. Mycopathologia 2020; 185:537-543. [PMID: 32458314 DOI: 10.1007/s11046-020-00457-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 05/14/2020] [Indexed: 01/25/2023]
Abstract
Candida species are common in the human oral microbiota and may cause oral candidiasis (OC) when the microbiota equilibrium is disturbed. Immunosuppressed individuals are susceptible to oral infections as individuals with Down syndrome (IDS) due to particularities of their mouth morphoanatomy, saliva and comorbidities. This study aimed to analyze the molecular epidemiology of Candida spp. from the oral cavity of IDS and their relatives. A case-control study with 80 IDS and 80 non-syndromic (non-DS) was evaluated by oral swab collection for culture on Sabouraud dextrose agar, selection of yeast colonies to Gram staining and culturing on chromogenic media. DNA extraction was performed with the phenol/chloroform method for screening of 6 Candida species medically important in PCR, applying SPSS for statistics. We confirmed four species in 46 IDS without use of antimicrobials (57.54%), with a high prevalence of C. albicans/Ca (93.48%/43) and 3 C. glabrata/Cg (6.52%), being 25 of these IDS (31.25%) colonized by species other than C. albicans: Ca + Cg (16), Ca + C. tropicalis/Ct (7) and Ca + C. krusei/Ck (2). Only 10 non-DS were colonized by one species (11.25%): 6 C. albicans, 2 C. glabrata, 1 C. tropicalis and 1 C. krusei. Previous OC was reported by 39 IDS (48.75%), being 33 positives for Candida spp. (84.61%) and 17 with active OC (21.25%). Five non-DS reported OC previously and had no active lesions. Behavioral changes and buccal health programs directed to IDS may help prevent OC and its recurrence, providing information on oral hygiene for self-care.
Collapse
Affiliation(s)
- Fernanda Cristina de Albuquerque Maranhão
- Department of Microbiology, Universidade Federal de Alagoas, Maceió, AL, Brazil. .,Laboratory of Clinical Microbiology, Institute of Biological and Health Sciences, Universidade Federal de Alagoas, Maceió, AL, 57022-222, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
4
|
Abstract
Vaginal complaints are one of the most common reasons women seek the advice of a health care provider. Uncomplicated infections such as vulvovaginal candidiasis, bacterial vaginosis, or trichomoniasis are easy to diagnose and treat. However, about 8% of patients will have a more complicated course with failure to respond to treatment or rapid recurrence of symptoms. Understanding the need for a methodical, diagnostic approach to help these women with recurrent or refractory cases of vaginal symptoms will aid the clinician achieve successful patient outcomes.
Collapse
Affiliation(s)
- Benjie Brown Mills
- Department of Obstetrics & Gynecology, Greenville Health System, University of South Carolina School of Medicine-Greenville, 890 West Faris Road, Suite 470, Greenville, SC 29605, USA.
| |
Collapse
|
5
|
Jafari Z, Motamedi M, Jalalizand N, Shokoohi GR, Charsizadeh A, Mirhendi H. Comparison of CHROMagar, polymerase chain reaction-restriction fragment length polymorphism, and polymerase chain reaction-fragment size for the identification of Candida species. Curr Med Mycol 2017; 3:10-15. [PMID: 29707668 PMCID: PMC5914921 DOI: 10.29252/cmm.3.3.10] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 12/05/2017] [Accepted: 12/25/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE The epidemiological alteration in the distribution of Candida species, as well as the significantly increasing trend of either intrinsic or acquired resistance of some of these fungi highlights the need for a reliable method for the identification of the species. Polymerase chain reaction (PCR) is one of the methods facilitating the quick and precise identification of Candida species. The aim of this study was to compare the efficiency of CHROMagar, PCR-restriction fragment length polymorphism (PCR-RFLP), and PCR-fragment size polymorphism (PCR-FSP) assays in the identification of Candida species to determine the benefits and limitations of these methods. MATERIALS AND METHODS This study was conducted on 107 Candida strains, including 20 standard strains and 87 clinical isolates. The identification of the isolates was accomplished by using CHROMagar as a conventional method. The PCR-RFLP assay was performed on the entire internal transcribed spacer (ITS) region of ribosomal DNA (rDNA), and the consequent enzymatic digestion was compared with PCR-FSP results in which ITS1 and ITS2 regions were separately PCR amplified. In both molecular assays, yeast identification was carried out through the specific electrophoretic profiles of the PCR products. RESULTS According to the results, the utilization of CHROMagar resulted in the identification of 29 (33.3%) Candida isolates, while the PCR-RFLP and PCR-FSP facilitated the identification of 83 (95.4%) and 80 (91.9%) clinical isolates, respectively. The obtained concordances between CHROMagar and PCR-RFLP, between CHROMagar and PCR-FSP, as well as between PCR-RFLP and PCR-FSP were 0.23, 0.20, and 0.77, respectively. CONCLUSION The recognition of the benefits and limitations of PCR methods allows for the selection of the most efficient technique for a fast and correct differentiation. The PCR-RFLP and PCR-FSP assays had satisfactory concordance. The PCR-FSP provides a rapid, technically simple, and cost-effective method for the identification of Candida species. Nevertheless, to accurately differentiate among the taxonomically related species, PCR-RFLP should be implemented.
Collapse
Affiliation(s)
- Zahra Jafari
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Marjan Motamedi
- Department of Medical Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Nilufar Jalalizand
- Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Gholam. R Shokoohi
- Department of Medical Parasitology and Mycology, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran
| | - Arezu Charsizadeh
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Mirhendi
- Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
6
|
Molecular Epidemiology and In Vitro Antifungal Susceptibility of Candida Isolates from Women with Vulvovaginal Candidiasis in Northern Cities of Khuzestan Province, Iran. Jundishapur J Microbiol 2017. [DOI: 10.5812/jjm.12804] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
7
|
Sobel JD. Recurrent vulvovaginal candidiasis. Am J Obstet Gynecol 2016; 214:15-21. [PMID: 26164695 DOI: 10.1016/j.ajog.2015.06.067] [Citation(s) in RCA: 271] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/29/2015] [Accepted: 06/30/2015] [Indexed: 02/02/2023]
Abstract
Recurrent vulvovaginal candidiasis (RVVC) is a common cause of significant morbidity in women in all strata of society affecting millions of women worldwide. Previously, RVVC occurrence was limited by onset of menopause but the widespread use of hormone replacement therapy has extended the at-risk period. Candida albicans remains the dominant species responsible for RVVC, however optimal management of RVVC requires species determination and effective treatment measures are best if species-specific. Considerable progress has been made in understanding risk factors that determine susceptibility to RVVC, particularly genetic factors, as well as new insights into normal vaginal defense immune mechanisms and their aberrations in RVVC. While effective control of RVVC is achievable with the use of fluconazole maintenance suppressive therapy, cure of RVVC remains elusive especially in this era of fluconazole drug resistance. Vaccine development remains a critical challenge and need.
Collapse
|
8
|
He Y, Geng W, Wang P, Xi L, Wang Z, Wu G, Wang C. Simultaneous detection of four common oral Candida species from blood samples by the fluorescence polarization assay. Cell Biochem Biophys 2015; 71:919-24. [PMID: 25308858 DOI: 10.1007/s12013-014-0284-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The genus Candida is both the commensal microbe and the opportunistic pathogen, containing approximately 200 species inhabiting in oral cavity of 53 % of the general population. Candida species can cause the diseases from local mucosal infections to systemic mycoses, even life-threatening infections in immunocompromised individuals. The timely differentiation of Candida species is important for the guidance of clinical medication. Four common Candida species in Chinese population (Candida albicans, Candida tropicalis, Candida glabrata, Candida krusei) were chosen as the targets to develop the rapid screening method in this work. Combined with amplification by asymmetric PCR, this parallel fluorescence polarization (FP) immunoassay is carried out in homogeneous solution phase. The limit of detection of the assay was shown to be 50 copies/mL in blood samples. The evaluation in multicenter manner showed excellent reproducibility and stability. The comparison between DNA sequencing and the FP immunoassay indicated that there was no significant difference between these methods. This molecular strategy-based method is simple, rapid, and feasible for identifying common Candida species and thereby holding great potential in the application of clinical laboratories.
Collapse
Affiliation(s)
- Yuhong He
- Department of Orthodontics, College of Stomatology, Shandong University, Jinan, 250012, China
| | | | | | | | | | | | | |
Collapse
|
9
|
Sobel JD, Akins RA. The Role of PCR in the Diagnosis of Candida Vulvovaginitis-a New Gold Standard? Curr Infect Dis Rep 2015; 17:488. [PMID: 26003471 DOI: 10.1007/s11908-015-0488-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PCR is recognized as a reliable technique for detection of all types of microorganisms. Being highly objective and reproducible also sensitive and specific, PCR is now widely used for sexually transmitted infection (STI) diagnosis. Potential, however, exists for detecting non-pathogens, and not identifying a pathogenic state decreases specificity or clinical significance. PCR Candida tests of vaginal specimens are now widely available and frequently used offering a modest to moderate increase in sensitivity and are likely to replace traditional culture and DNA homology testing. Nevertheless, there remain considerable gaps in our knowledge regarding the usefulness and applications of these expensive tests.
Collapse
Affiliation(s)
- J D Sobel
- Division of Infectious Diseases, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA,
| | | |
Collapse
|
10
|
Multi-probe real-time PCR identification of four common Candida species in blood culture broth. Mycopathologia 2014; 177:251-61. [PMID: 24740169 DOI: 10.1007/s11046-014-9743-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 03/29/2014] [Indexed: 10/25/2022]
Abstract
We developed a single-tube real-time polymerase chain reaction (PCR) assay with multiple hybridization probes for detecting Candida albicans, C. tropicalis, C. glabrata, and C. parapsilosis. Primers were designed to amplify 18S rRNA gene of the genus Candida, and DNA probes were designed to hybridize two areas of the amplicons. The amplification curves and specific melting peaks of the probes hybridized with PCR product were used for definite species identifications. The reaction specificity was 100 % when evaluating the assay using DNA samples from 21 isolates of fungal and bacterial species. The assay was further evaluated in 129 fungal blood culture broth samples which were culture positive for fungus. Of the 129 samples, 119 were positively identified as: C. albicans (39), C. tropicalis (30), C. parapsilosis (23), C. glabrata (20), Candida spp. (5), and two samples containing mixed C. glabrata/C. albicans and C. glabrata/C. tropicalis. The five Candida spp. were identified by sequencing analysis as C. krusei, C. dubliniensis, C. aquaetextoris, and two isolates of C. athensensis. Of the ten samples which showed negative PCR results, six were Cryptococcus neoformans, and the others were Trichosporon sp., Rhodotorula sp., Fusarium sp., and Penicillium marneffei. Our findings show that the assay was highly effective in identifying the four medically important Candida species. The results can be available within 3 h after positivity of a blood culture broth sample.
Collapse
|
11
|
Hohnadel M, Felden L, Fijuljanin D, Jouette S, Chollet R. A new ultrasonic high-throughput instrument for rapid DNA release from microorganisms. J Microbiol Methods 2014; 99:71-80. [DOI: 10.1016/j.mimet.2014.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 02/04/2014] [Accepted: 02/06/2014] [Indexed: 11/25/2022]
|
12
|
Candida identification: a journey from conventional to molecular methods in medical mycology. World J Microbiol Biotechnol 2014; 30:1437-51. [PMID: 24379160 DOI: 10.1007/s11274-013-1574-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 12/02/2013] [Indexed: 12/17/2022]
Abstract
The incidence of Candida infections have increased substantially in recent years due to aggressive use of immunosuppressants among patients. Use of broad-spectrum antibiotics and intravascular catheters in the intensive care unit have also attributed with high risks of candidiasis among immunocompromised patients. Among Candida species, C. albicans accounts for the majority of superficial and systemic infections, usually associated with high morbidity and mortality often caused due to increase in antimicrobial resistance and restricted number of antifungal drugs. Therefore, early detection of candidemia and correct identification of Candida species are indispensable pre-requisites for appropriate therapeutic intervention. Since blood culture based methods lack sensitivity, and species-specific identification by conventional method is time-consuming and often leads to misdiagnosis within closely related species, hence, molecular methods may provide alternative for accurate and rapid identification of Candida species. Although, several molecular approaches have been developed for accurate identification of Candida species but the internal transcribed spacer 1 and 2 (ITS1 and ITS2) regions of the rRNA gene are being used extensively in a variety of formats. Of note, ITS sequencing and PCR-RFLP analysis of ITS region seems to be promising as a rapid, easy, and cost-effective method for identification of Candida species. Here, we review a number of existing techniques ranging from conventional to molecular approaches currently in use for the identification of Candida species. Further, advantages and limitations of these methods are also discussed with respect to their discriminatory power, reproducibility, and ease of performance.
Collapse
|
13
|
Frickmann H, Lakner A, Essig A, Poppert S. Rapid identification of yeast by fluorescencein situhybridisation from broth and blood cultures. Mycoses 2012; 55:521-31. [DOI: 10.1111/j.1439-0507.2012.02214.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
14
|
Amir LH, Cullinane M, Garland SM, Tabrizi SN, Donath SM, Bennett CM, Cooklin AR, Fisher JRW, Payne MS. The role of micro-organisms (Staphylococcus aureus and Candida albicans) in the pathogenesis of breast pain and infection in lactating women: study protocol. BMC Pregnancy Childbirth 2011; 11:54. [PMID: 21777483 PMCID: PMC3151214 DOI: 10.1186/1471-2393-11-54] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 07/22/2011] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The CASTLE (Candida and Staphylococcus Transmission: Longitudinal Evaluation) study will investigate the micro-organisms involved in the development of mastitis and "breast thrush" among breastfeeding women. To date, the organism(s) associated with the development of breast thrush have not been identified. The CASTLE study will also investigate the impact of physical health problems and breastfeeding problems on maternal psychological health in the early postpartum period. METHODS/DESIGN The CASTLE study is a longitudinal descriptive study designed to investigate the role of Staphylococcus spp (species) and Candida spp in breast pain and infection among lactating women, and to describe the transmission dynamics of S. aureus and Candida spp between mother and infant. The relationship between breastfeeding and postpartum health problems as well as maternal psychological well-being is also being investigated. A prospective cohort of four hundred nulliparous women who are at least thirty six weeks gestation pregnant are being recruited from two hospitals in Melbourne, Australia (November 2009 to June 2011). At recruitment, nasal, nipple (both breasts) and vaginal swabs are taken and participants complete a questionnaire asking about previous known staphylococcal and candidal infections. Following the birth, participants are followed-up six times: in hospital and then at home weekly until four weeks postpartum. Participants complete a questionnaire at each time points to collect information about breastfeeding problems and postpartum health problems. Nasal and nipple swabs and breast milk samples are collected from the mother. Oral and nasal swabs are collected from the baby. A telephone interview is conducted at eight weeks postpartum to collect information about postpartum health problems and breastfeeding problems, such as mastitis and nipple and breast pain. DISCUSSION This study is the first longitudinal study of the role of both staphylococcal and candidal colonisation in breast infections and will help to resolve the current controversy about which is the primary organism in the condition known as breast thrush. This study will also document transmission dynamics of S. aureus and Candida spp between mother and infant. In addition, CASTLE will investigate the impact of common maternal physical health symptoms and the effect of breastfeeding problems on maternal psychological well-being.
Collapse
Affiliation(s)
- Lisa H Amir
- Mother & Child Health Research, La Trobe University, Melbourne, VIC 3000, Australia
| | - Meabh Cullinane
- Mother & Child Health Research, La Trobe University, Melbourne, VIC 3000, Australia
| | - Suzanne M Garland
- Women's Centre for Infectious Diseases, Bio 21 Institute, Parkville, VIC 3052, Australia
- University of Melbourne Department of Obstetrics and Gynaecology, The Royal Women's Hospital, Parkville, VIC 3052, Australia
- Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC 3052, Australia
| | - Sepehr N Tabrizi
- Women's Centre for Infectious Diseases, Bio 21 Institute, Parkville, VIC 3052, Australia
- University of Melbourne Department of Obstetrics and Gynaecology, The Royal Women's Hospital, Parkville, VIC 3052, Australia
- Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC 3052, Australia
| | - Susan M Donath
- Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC 3052, Australia
- University of Melbourne Department of Paediatrics, The Royal Children's Hospital, Parkville, VIC 3052, Australia
| | | | | | - Jane RW Fisher
- Jean Hailes Research Unit, Monash University, Clayton, VIC 3168, Australia
- Centre for Women's Health, Gender and Society, University of Melbourne, Carlton, VIC 3053, Australia
| | - Matthew S Payne
- Mother & Child Health Research, La Trobe University, Melbourne, VIC 3000, Australia
- Women's Centre for Infectious Diseases, Bio 21 Institute, Parkville, VIC 3052, Australia
| |
Collapse
|
15
|
Performance and cost analysis of matrix-assisted laser desorption ionization-time of flight mass spectrometry for routine identification of yeast. J Clin Microbiol 2011; 49:1614-6. [PMID: 21270234 DOI: 10.1128/jcm.02381-10] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry was compared to phenotypic testing for yeast identification. MALDI-TOF mass spectrometry yielded 96.3% and 84.5% accurate species level identifications (spectral scores, ≥ 1.8) for 138 common and 103 archived strains of yeast. MALDI-TOF mass spectrometry is accurate, rapid (5.1 min of hands-on time/identification), and cost-effective ($0.50/sample) for yeast identification in the clinical laboratory.
Collapse
|
16
|
Susceptibility of Candida spp. clinical isolates to antimycotics and disinfectants. Open Life Sci 2010. [DOI: 10.2478/s11535-010-0068-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe incidence of candidiasis among immunocompromised patients and emergence of antimycotics resistant strains has increased significantly. The aims of this study were: to examine the in vitro activity of antimycotics and biocides against Candida clinical isolates; to detect cross-resistance of fungi to these preparations and to estimate whether disinfectants applied in hospital areas are active against clinical Candida isolates. In vitro susceptibility of 102 Candida isolates to eight antimycotics was examined by Etest and ATB Fungus. Sensitivity of these strains to four disinfectants and an antiseptic agent was tested according to EN 1275:2005. Amphotericin B, caspofungin and 5-fluorocytosine were the most effective antimycotics against all Candida isolates. Resistance to itraconazole and fluconazole was observed among C. krusei and C. glabrata. The MICs (Minimal Inhibitory Concentrations) for ketoconazole, voriconazole and posaconazole against Candida albicans ranged: 0.003 - >32 μg/ml and one strain was resistant to three agents tested. All analysed Candida strains were sensitive to biocides containing either chlorine, aldehyde, alcohol mixtures, glucoprotamin or chlorhexidine gluconate with isopropanol. Sensitivity to these agents was observed at concentrations lower than those concentrations recommended by manufacturers to achieve proper biocidal activity to those preparations. Our data suggest that these disinfectants can be effectively applied in clinical wards to prevent nosocomial Candida infections.
Collapse
|
17
|
Guo R, Chen Z, Chen N, Chen Y. Quantitative Real-Time PCR Analysis of Intestinal Regular Fungal Species in Fecal Samples From Patients With Chronic Hepatitis B Virus Infection. Lab Med 2010. [DOI: 10.1309/lmmc0wvzxd13pujg] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
|
18
|
Alves IA, Camargo FPD, Goulart LS. Identificação por PCR e sensibilidade a antifúngicos de isolados clínicos vaginais de Candida sp. Rev Soc Bras Med Trop 2010; 43:575-9. [DOI: 10.1590/s0037-86822010000500021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2009] [Accepted: 05/14/2010] [Indexed: 11/21/2022] Open
Abstract
INTRODUÇÃO: A candidíase vaginal é uma condição que afeta um grande número de mulheres em idade fértil. Candida albicans é a espécie mais frequentemente isolada de secreção vaginal, entretanto, outras espécies mais resistentes às drogas antifúngicas podem ser isoladas de amostras clínicas vaginais. MÉTODOS: Foram identificadas as espécies de 30 isolados vaginais de Candida sp por PCR utilizando o primer universal ITS4 e primers espécie-específicos para C. albicans, C. glabrata, C. tropicalis e C. krusei. A sensibilidade destes isolados frente à anfotericina B, fluconazol e voriconazol foi determinada pelo método de macrodiluição M27-A2 do CLSI. RESULTADOS: Através dos ensaios de PCR, 28 isolados foram caracterizados como C. albicans e 2 isolados apresentaram amplificação para os primers específicos de C. albicans e C. glabrata. A concentração inibitória mínima para anfotericina B variou de 0,03µg/mL a 0,25µg/mL, para o fluconazol de 0,125µg/mL a 16µg/mL e para o voriconazol de 0,03µg/mL a 0,25µg/mL. CONCLUSÕES: A identificação de Candida ao nível de espécie através de ensaios de PCR deve ser relevante para o gerenciamento clínico destas infecções.
Collapse
|
19
|
Deak E, Etienne KA, Lockhart SR, Gade L, Chiller T, Balajee SA. Utility of a Luminex-based assay for multiplexed, rapid species identification of Candida isolates from an ongoing candidemia surveillance. Can J Microbiol 2010; 56:348-51. [PMID: 20453902 DOI: 10.1139/w10-003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A Candida-specific Luminex-based assay with 11 probes was employed for multiplexed, rapid identification of 1182 Candida sp. isolates that were received as part of an ongoing population-based surveillance. All the Candida isolates were previously identified by a combination of methods, including phenotype and sequence analysis. Results showed that the Luminex assay was an attractive alternative to reference methods, as it is rapid, yields correct species identification, and is user friendly.
Collapse
Affiliation(s)
- Eszter Deak
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | | | | | | | | | | |
Collapse
|
20
|
Lu W, Gu D, Chen X, Xiong R, Liu P, Yang N, Zhou Y. Application of an oligonucleotide microarray-based nano-amplification technique for the detection of fungal pathogens. Clin Chem Lab Med 2010; 48:1507-14. [PMID: 20618094 DOI: 10.1515/cclm.2010.284] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The traditional techniques for diagnosis of invasive fungal infections in the clinical microbiology laboratory need improvement. These techniques are prone to delay results due to their time-consuming process, or result in misidentification of the fungus due to low sensitivity or low specificity. The aim of this study was to develop a method for the rapid detection and identification of fungal pathogens. METHODS The internal transcribed spacer two fragments of fungal ribosomal DNA were amplified using a polymerase chain reaction for all samples. Next, the products were hybridized with the probes immobilized on the surface of a microarray. These species-specific probes were designed to detect nine different clinical pathogenic fungi including Candida albicans, Candida tropocalis, Candida glabrata, Candida parapsilosis, Candida krusei, Candida lusitaniae, Candida guilliermondii, Candida keyfr, and Cryptococcus neoformans. The hybridizing signals were enhanced with gold nanoparticles and silver deposition, and detected using a flatbed scanner or visually. RESULTS Fifty-nine strains of fungal pathogens, including standard and clinically isolated strains, were correctly identified by this method. The sensitivity of the assay for Candida albicans was 10 cells/mL. Ten cultures from clinical specimens and 12 clinical samples spiked with fungi were also identified correctly. CONCLUSIONS This technique offers a reliable alternative to conventional methods for the detection and identification of fungal pathogens. It has higher efficiency, specificity and sensitivity compared with other methods commonly used in the clinical laboratory.
Collapse
Affiliation(s)
- Weiping Lu
- Department of Clinical Laboratory, Third Affiliated Hospital of Third Military Medical University, Chongqing, PR China
| | | | | | | | | | | | | |
Collapse
|
21
|
Jegier B, Jaszewski R, Kurnatowski P, Kuba K, Lelonek M. Mycotic DNA in non-atherosclerotic aortic wall of coronary patients is associated with sICAM-1 expression. Circ J 2010; 74:749-53. [PMID: 20173302 DOI: 10.1253/circj.cj-09-0632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Atherosclerosis is currently being investigated as a chronic inflammatory process and the role of infectious agents is unclear. The presence of mycotic DNA in the wall of the non-atherosclerotic aorta of patients with coronary artery disease (CAD) and its association with levels of soluble intercellular adhesion molecule (sICAM)-1 expression was examined in the present study. METHODS AND RESULTS In 40 patients with CAD and a comparative group of 20 patients with aortic valve stenosis (AS) without CAD, specimens of the aortic wall were obtained during cardiac surgery. Mycotic DNA was analyzed by polymerase chain reaction (PCR) using a fungus-specific universal primer pair, ITS3 and ITS4, to amplify a portion of the 5.8S rDNA region, the entire ITS2 region and a portion of the 28S rDNA region, and using a species-specific primer pair, CALB1 and CALB2, to specifically amplify Candida (C.) albicans. The nested PCR method was performed to amplify the intergenic transcribed spacer regions of the rRNAs of Candida species. Before surgery the serum level of sICAM-1 was estimated. Mycotic DNA was detected in 48% of the CAD patients and in 40% of the AS patients, with C. albicans DNA in 58% and 100%, respectively (P>0.05). In CAD patients with a high level of sICAM-1, C. albicans DNA was found more frequently than in patients without elevated levels of sICAM-1 (P<0.05). CONCLUSIONS Mycotic DNA was found in the non-atherosclerotic aortic wall of CAD patients as well as in patients with AS. In the CAD patients C. albicans DNA was related to sICAM-1 expression.
Collapse
Affiliation(s)
- Bogdan Jegier
- Department of Cardiac Surgery, Medical University of Lodz, Lodz, Poland.
| | | | | | | | | |
Collapse
|
22
|
Abstract
PURPOSE OF REVIEW Antifungal drug resistance is a confounding factor that negatively impacts clinical outcome for patients with serious mycoses. Early detection of fungi in blood or other specimens with a rapid assessment of drug susceptibility could improve the survival of patients with invasive disease by accelerating the initiation of appropriate antifungal treatment. Recent years have seen the growth of molecular technology that is ideally suited for fungal identification and assessment of drug resistance mechanisms. RECENT FINDINGS Elucidation of the genetic mechanisms responsible for triazole and echinocandin resistance in prominent Candida spp. and Aspergillus spp. provides an opportunity to develop molecular diagnostic platforms suitable for rapid detection of primary and secondary drug resistance. Several highly dynamic and robust amplification/detection methodologies are now available that can provide simultaneous species identification and high fidelity discrimination of resistance alleles. SUMMARY Molecular diagnostic platforms are ideal for rapid detection of fungal pathogens and they provide an opportunity to develop in parallel molecular assays that can evaluate antifungal drug resistance.
Collapse
|
23
|
Lau A, Chen S, Sleiman S, Sorrell T. Current status and future perspectives on molecular and serological methods in diagnostic mycology. Future Microbiol 2009; 4:1185-222. [DOI: 10.2217/fmb.09.70] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Invasive fungal infections are an important cause of infectious morbidity. Nonculture-based methods are increasingly used for rapid, accurate diagnosis to improve patient outcomes. New and existing DNA amplification platforms have high sensitivity and specificity for direct detection and identification of fungi in clinical specimens. Since laboratories are increasingly reliant on DNA sequencing for fungal identification, measures to improve sequence interpretation should support validation of reference isolates and quality control in public gene repositories. Novel technologies (e.g., isothermal and PNA FISH methods), platforms enabling high-throughput analyses (e.g., DNA microarrays and Luminex® xMAP™) and/or commercial PCR assays warrant further evaluation for routine diagnostic use. Notwithstanding the advantages of molecular tests, serological assays remain clinically useful for patient management. The serum Aspergillus galactomannan test has been incorporated into diagnostic algorithms of invasive aspergillosis. Both the galactomannan and the serum β-D-glucan test have value for diagnosing infection and monitoring therapeutic response.
Collapse
Affiliation(s)
- Anna Lau
- Centre for Infectious Diseases & Microbiology, University of Sydney, Sydney, Australia
| | - Sharon Chen
- Centre for Infectious Diseases & Microbiology, University of Sydney, Sydney, Australia and Centre for Infectious Diseases & Microbiology Laboratory Services, Institute of Clinical Pathology & Medical Research, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Sue Sleiman
- Centre for Infectious Diseases & Microbiology Laboratory Services, Institute of Clinical Pathology & Medical Research, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Tania Sorrell
- Centre for Infectious Diseases & Microbiology, Westmead Hospital, Darcy and Hawkesbury Roads, Westmead, NSW 2145, Australia
| |
Collapse
|
24
|
Martínez JMG, Gómez EV, Pemán J, Cantón E, García MG, del Castillo Agudo L. Identification of pathogenic yeast species by polymerase chain reaction amplification of the RPS0 gene intron fragment. J Appl Microbiol 2009; 108:1917-27. [PMID: 19968730 DOI: 10.1111/j.1365-2672.2009.04595.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
AIMS This work focuses on the development of a method for the identification of pathogenic yeast. With this aim, we target the nucleotide sequence of the RPS0 gene of pathogenic yeast species with specific PCR primers. PCR analysis was performed with both the genomic DNA, whole cells of clinical isolates of Candida species and clinical samples. METHODS AND RESULTS A single pairs of primers, deduced from the nucleotide sequence of the RPS0 gene from pathogenic yeast, were used in PCR analysis performed with both the genomic DNA and whole cells of clinical isolates of Candida species and clinical samples. The primers designed are highly specific for their respective species and produce amplicons of the expected sizes and fail to amplify any DNA fragment from the other species tested. The set of primers was tested successfully for the identification of yeast from colonies, blood cultures and clinical samples. These results indicate that genes containing intron sequences may be useful for designing species-specific primers for the identification of fungal strains by PCR. The sensitivity of the method with genomic DNA was evaluated with decreasing DNA concentrations (200 ng to 1 pg) and different cell amounts (10(7)-10(5) cells). CONCLUSION The results obtained show that the amplification of RPS0 sequences may be suitable for the identification of pathogenic and other yeast species. SIGNIFICANCE AND IMPACT OF THE STUDY Identification of Candida species using molecular approaches with high discriminatory power is important in determining adequate measures for the interruption of transmission of this yeast. The approach described in this work is based on standard technology, and it is specific, sensitive and does not involve complex and expensive equipment. Furthermore, the method developed in this work not only can be used in eight yeast species, but also provides the basis to design primers for other fungi species of clinical, industrial or environmental interest.
Collapse
Affiliation(s)
- J M García Martínez
- Departamento de Microbiología y Ecología, Facultad de Farmacia, Universidad de Valencia, Valencia, Spain
| | | | | | | | | | | |
Collapse
|
25
|
Ruan SY, Kuo YW, Huang CT, Hsiue HC, Hsueh PR. Infections due to Candida haemulonii: species identification, antifungal susceptibility and outcomes. Int J Antimicrob Agents 2009; 35:85-8. [PMID: 19786341 DOI: 10.1016/j.ijantimicag.2009.08.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 08/13/2009] [Accepted: 08/14/2009] [Indexed: 11/25/2022]
Abstract
Here we report the clinical features and treatment outcomes of three patients with Candida haemulonii infection. Candida haemulonii was confirmed by sequence analysis of the internal transcribed spacer (ITS) regions of the rRNA genes and the 18S rRNA genes. Two of the three isolates were associated with fungaemia and reduced susceptibility to fluconazole [minimum inhibitory concentrations (MICs) of 16 mg/L] and amphotericin B (MICs of 2 mg/L). However, one of these two patients responded to fluconazole therapy. Echinocandins, voriconazole and posaconazole demonstrated excellent in vitro potency against the isolates.
Collapse
Affiliation(s)
- Sheng-Yuan Ruan
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan
| | | | | | | | | |
Collapse
|
26
|
Haas B, Nathens AB. Future diagnostic and therapeutic approaches in surgical infections. Surg Clin North Am 2009; 89:539-54, xi. [PMID: 19281899 DOI: 10.1016/j.suc.2008.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Despite ongoing efforts to standardize therapy and improve management, the morbidity and mortality associated with surgical infections remain high. Continued innovation is required to improve outcomes further, particularly in the face of the increasing prevalence of multidrug resistant organisms. Although they remain in the experimental stages, a number of recent advances have the potential to have significant impact on the management and outcomes of surgical infections. These include novel diagnostic strategies, antimicrobials targeting microbial virulence factors, novel vaccines, and risk stratification based on genetic profiling.
Collapse
Affiliation(s)
- Barbara Haas
- Department of Surgery, University of Toronto, Toronto, Ontario, M5G 1L5, Canada.
| | | |
Collapse
|
27
|
Identification of fungal species by fragment length analysis of the internally transcribed spacer 2 region. Eur J Clin Microbiol Infect Dis 2008; 28:613-22. [DOI: 10.1007/s10096-008-0683-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 11/29/2008] [Indexed: 11/26/2022]
|
28
|
Arancia S, Sandini S, Cassone A, De Bernardis F. Use of 65-kDa mannoprotein gene primers for real-time identification of Candida albicans. CURRENT FUNGAL INFECTION REPORTS 2008. [DOI: 10.1007/s12281-008-0031-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
29
|
Panjaitan M, Amir LH, Costa AM, Rudland E, Tabrizi S. Polymerase chain reaction in detection of Candida albicans for confirmation of clinical diagnosis of nipple thrush. Breastfeed Med 2008; 3:185-7. [PMID: 18778216 DOI: 10.1089/bfm.2008.0106] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Mariana Panjaitan
- Key Centre for Women's Health in Society, School of Population Health, University of Melbourne, Victoria, Australia
| | - Lisa H. Amir
- Key Centre for Women's Health in Society, School of Population Health, University of Melbourne, Victoria, Australia
- Mother & Child Health Research, La Trobe University, Victoria, Australia
| | - Anna-Maria Costa
- Molecular Microbiology Laboratory, The Royal Women's Hospital, Melbourne, Victoria, Australia
| | - Elice Rudland
- Molecular Microbiology Laboratory, The Royal Women's Hospital, Melbourne, Victoria, Australia
| | - Sepehr Tabrizi
- Molecular Microbiology Laboratory, The Royal Women's Hospital, Melbourne, Victoria, Australia
- Department of Obstetrics and Gynaecology, University of Melbourne, Victoria, Australia
| |
Collapse
|
30
|
Abaci Ö, Halki-Uztan A, Ates M. Specific identification ofCandida albicans andCandida dubliniensis by PCR using species-specific primers. ANN MICROBIOL 2008. [DOI: 10.1007/bf03175338] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
31
|
Boyanton BL, Luna RA, Fasciano LR, Menne KG, Versalovic J. DNA pyrosequencing-based identification of pathogenic Candida species by using the internal transcribed spacer 2 region. Arch Pathol Lab Med 2008; 132:667-74. [PMID: 18384218 DOI: 10.5858/2008-132-667-dpiopc] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2007] [Indexed: 11/06/2022]
Abstract
CONTEXT The incidence of infections due to diverse Candida species is increasing, with correspondingly different antifungal susceptibility patterns. Routine yeast identification methods cause significant delays in appropriate patient management. OBJECTIVE A DNA pyrosequencing strategy was evaluated for identification of pathogenic Candida species associated with human infections. DESIGN Clinical (n = 51) and commercial (n = 9) Candida isolates were identified in a blinded, parallel study consisting of routine fungal cultures and biochemical analyses in comparison with DNA pyrosequencing. RESULTS DNA pyrosequencing yielded species-level identification of all 60 Candida isolates, and sequencing interpretations agreed in all cases with results of biochemical and morphologic testing. Different Candida species were identified, such as C. albicans, C. dubliniensis, C. glabrata, C. guilliermondii, C. krusei, C. lusitaniae, C. parapsilosis, and C. tropicalis. Automated and manual approaches to DNA sequence interpretation, each coupled with the Identifire identification software, demonstrated 100% agreement with respect to Candida species identification. Twenty-one isolates yielded intraspecies DNA sequence differences (90%-98% nucleic acid sequence identity) by automated interpretation. Sequence differences resulted from single-nucleotide polymorphisms or single-base additions/deletions, in addition to interpretative challenges in homopolymeric tracts. CONCLUSION DNA pyrosequencing coupled with automated DNA sequence alignment provides a practical approach for accurate and timely identification of Candida pathogens. Relatively rapid and facile genotypic studies by DNA pyrosequencing matched the effectiveness of extensive biochemical/morphologic studies for yeast identification.
Collapse
Affiliation(s)
- Bobby L Boyanton
- Department of Pathology, Baylor College of Medicine, Houston, USA.
| | | | | | | | | |
Collapse
|
32
|
Rapid differentiation of phenotypically similar yeast species by single-strand conformation polymorphism analysis of ribosomal DNA. Appl Environ Microbiol 2008; 74:2604-11. [PMID: 18344345 DOI: 10.1128/aem.02223-07] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Single-strand conformation polymorphism (SSCP) analysis of ribosomal DNA (rDNA) was investigated for rapid differentiation of phenotypically similar yeast species. Sensitive tests indicated that some yeast strains with one, most strains with two, and all strains with three or more nucleotide differences in the internal transcribed spacer 1 (ITS1) or ITS2 region could be distinguished by PCR SSCP analysis. The discriminative power of SSCP in yeast species differentiation was demonstrated by comparative studies of representative groups of yeast species from ascomycetes and basidiomycetes, including Saccharomyces species, medically important Candida species, and phylloplane basidiomycetous yeast species. Though the species within each group selected are closely related and have relatively similar rDNA sequences, they were clearly differentiated by PCR-SSCP analysis of the ITS1 region, given the amplified fragments were less than 350 bp in sizes. By using SSCP analysis for rapid screening of yeast strains with different rDNA sequences, species diversity existing in a large collection of yeast strains from natural sources was effectively and thoroughly investigated with substantially reduced time and cost in subsequent DNA sequencing.
Collapse
|
33
|
Carvalho A, Costa-De-Oliveira S, Martins ML, Pina-Vaz C, Rodrigues AG, Ludovico P, Rodrigues F. Multiplex PCR identification of eight clinically relevant Candida species. Med Mycol 2008; 45:619-27. [PMID: 17885953 DOI: 10.1080/13693780701501787] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Invasive fungal infections, specifically candidemia, constitute major public health problems with high mortality rates. Therefore, in the last few years, the development of novel diagnostic methods has been considered a critical issue. Herein we describe a multiplex PCR strategy allowing the identification of 8 clinically relevant yeasts of the Candida genus, namely C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, C. guilliermondii, C. lusitaniae and C. dubliniensis. This method is based on the amplification of two fragments from the ITS1 and ITS2 regions by the combination of 2 yeast-specific and 8 species-specific primers in a single PCR reaction. Results from the identification of 231 clinical isolates are presented pointing to the high specificity of this procedure. Furthermore, several Candida isolates were identified directly from clinical specimens which also attests to the method's direct laboratory application. The results from the multiplex reactions with other microorganisms that usually co-infect patients also confirmed its high specificity in the identification of Candida species. Moreover, this method is simple and presents a sensitivity of approximately 2 cells per ml within 5 hours. Furthermore, it allows discrimination of individual Candida species within polyfungal samples. This novel method may therefore provide a clinical diagnostic procedure with direct applicability.
Collapse
Affiliation(s)
- A Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal
| | | | | | | | | | | | | |
Collapse
|
34
|
Barada G, Basma R, Khalaf RA. Microsatellite DNA Identification and Genotyping of Candida albicans from Lebanese Clinical Isolates. Mycopathologia 2008; 165:115-25. [DOI: 10.1007/s11046-008-9089-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Accepted: 01/07/2008] [Indexed: 11/30/2022]
|
35
|
Bašková L, Landlinger C, Preuner S, Lion T. The Pan-AC assay: a single-reaction real-time PCR test for quantitative detection of a broad range of Aspergillus and Candida species. J Med Microbiol 2007; 56:1167-1173. [PMID: 17761478 DOI: 10.1099/jmm.0.47212-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In view of the growing incidence and the high mortality of invasive aspergillosis and candidiasis, adequate diagnostic techniques permitting timely onset of treatment are of paramount importance. More than 90 % of all invasive fungal infections in immunocompromised individuals can be attributed to Candida and Aspergillus species. To date, standardized techniques permitting rapid, sensitive and, no less importantly, economic screening for the clinically most relevant fungi are lacking. In the present report, a real-time quantitative PCR assay, developed for the detection of the most common pathogenic Candida and Aspergillus species, is described. The single-reaction PCR assay targets a judiciously selected region of the 28S subunit of the fungal rDNA gene. The unique design of the universal primer/probe system, including a pan-Aspergillus and pan-Candida (Pan-AC) hydrolysis probe, facilitates the detection of numerous Aspergillus species (e.g. Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus versicolor and Aspergillus nidulans) and Candida species (e.g. Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Candida kefyr, Candida guilliermondii, Candida lusitaniae and Candida dubliniensis). The assay permits highly reproducible detection of 10 fg fungal DNA, which corresponds to a fraction of a fungal genome, and facilitates accurate quantification of fungal load across a range of at least five logs. Upon standardization of the technique using cultured fungal strains, the applicability in the clinical setting was assessed by investigating a series of clinical specimens from patients with documented fungal infections (n=17). The Pan-AC assay provides an attractive and economic approach to the screening and monitoring of invasive aspergillosis and candidiasis, which is readily applicable to routine clinical diagnosis.
Collapse
Affiliation(s)
- Lenka Bašková
- Division of Molecular Microbiology and Development of Genetic Diagnostics, Children's Cancer Research Institute, A-1090 Vienna, Austria
| | - Christine Landlinger
- Division of Molecular Microbiology and Development of Genetic Diagnostics, Children's Cancer Research Institute, A-1090 Vienna, Austria
| | - Sandra Preuner
- Division of Molecular Microbiology and Development of Genetic Diagnostics, Children's Cancer Research Institute, A-1090 Vienna, Austria
| | - Thomas Lion
- Division of Molecular Microbiology and Development of Genetic Diagnostics, Children's Cancer Research Institute, A-1090 Vienna, Austria
| |
Collapse
|
36
|
Abstract
The focus of this review is the evolution of biochemical phenotypic yeast identification methods with emphasis on conventional approaches, rapid screening tests, chromogenic agars, comprehensive commercial methods, and the eventual migration to genotypic methods. As systemic yeast infections can be devastating and resistance is common in certain species, accurate identification to the species level is paramount for successful therapy and appropriate patient care.
Collapse
Affiliation(s)
- D H Pincus
- bioMérieux, Inc., Hazelwood, Missouri 63042, USA.
| | | | | |
Collapse
|
37
|
Zeng X, Kong F, Halliday C, Chen S, Lau A, Playford G, Sorrell TC. Reverse line blot hybridization assay for identification of medically important fungi from culture and clinical specimens. J Clin Microbiol 2007; 45:2872-80. [PMID: 17634313 PMCID: PMC2045312 DOI: 10.1128/jcm.00687-07] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We evaluated a combined panfungal PCR-reverse line blot (RLB) hybridization assay based on internal transcribed spacer 1 (ITS1) and ITS2 region polymorphisms to identify 159 Candida, Cryptococcus neoformans, and Aspergillus isolates (22 species). Its utility to identify fungal pathogens directly from 27 clinical specimens was also determined. ITS sequence analysis was performed to resolve discrepant identifications or where no RLB result was obtained. Species-specific ITS2- and ITS1-based probes correctly identified 155 of 159 isolates (98%) and 149 (93.7%) isolates, respectively. All strains were unambiguously differentiated with the exception of cross-reactivity between the Candida norvegensis probe and Candida haemulonii DNA product. Species identification of the pathogen was made for all 21 specimens (sensitivity of 100%) where species-specific probes were included in the RLB; however, there was no ITS2 probe-based hybridization signal for two specimens. Results were concordant with the culture results for 18 (85.7%) specimens. The assay was able to provide species identification in the absence of a culture result (two specimens) and to detect mixed infection (one specimen). The results indicate that the RLB assay is capable of reliably detecting yeasts and Aspergillus spp. in clinical specimens and that the incorporation of both ITS1- and ITS2-targeted probes is required for optimal sensitivity. The test has potential utility in the early diagnosis of invasive fungal infection, since "fungal" DNA was detected in all 27 specimens. Prior to incorporation of probes to detect other fungal species, ITS sequencing may be performed to achieve species identification.
Collapse
Affiliation(s)
- Xianyu Zeng
- Centre for Infectious Diseases and Microbiology-Public Health (CIDM-PH), Institute of Clinical Pathology and Medical Research, Westmead Hospital, Westmead, Australia
| | | | | | | | | | | | | |
Collapse
|
38
|
Metwally L, Hogg G, Coyle PV, Hay RJ, Hedderwick S, McCloskey B, O'Neill HJ, Ong GM, Thompson G, Webb CH, McMullan R. Rapid differentiation between fluconazole-sensitive and -resistant species of Candida directly from positive blood-culture bottles by real-time PCR. J Med Microbiol 2007; 56:964-970. [PMID: 17577063 DOI: 10.1099/jmm.0.47149-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In view of both the delay in obtaining identification by conventional methods following blood-culture positivity in patients with candidaemia and the close relationship between species and fluconazole (FLC) susceptibility, early speciation of positive blood cultures has the potential to influence therapeutic decisions. The aim was to develop a rapid test to differentiate FLC-resistant from FLC-sensitive Candida species. Three TaqMan-based real-time PCR assays were developed to identify up to six Candida species directly from BacT/Alert blood-culture bottles that showed yeast cells on Gram staining at the time of initial positivity. Target sequences in the rRNA gene complex were amplified, using a consensus two-step PCR protocol, to identify Candida albicans, Candida parapsilosis, Candida tropicalis, Candida
dubliniensis, Candida
glabrata and Candida krusei; these are the most commonly encountered Candida species in blood cultures. The first four of these (the characteristically FLC-sensitive group) were identified in a single reaction tube using one fluorescent TaqMan probe targeting 18S rRNA sequences conserved in the four species. The FLC-resistant species C. krusei and C. glabrata were detected in two further reactions, each with species-specific probes. This method was validated with clinical specimens (blood cultures) positive for yeast (n=33 sets) and the results were 100 % concordant with those of phenotypic identification carried out concomitantly. The reported assay significantly reduces the time required to identify the presence of C. glabrata and C. krusei in comparison with a conventional phenotypic method, from ∼72 to <3 h, and consequently allows optimization of the antifungal regimen at an earlier stage.
Collapse
Affiliation(s)
- L Metwally
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - G Hogg
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - P V Coyle
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - R J Hay
- Queen's University of Belfast, School of Medicine and Dentistry, Belfast, Northern Ireland
| | - S Hedderwick
- Department of Infectious Diseases, Royal Victoria Hospital, Belfast, Northern Ireland
| | - B McCloskey
- Regional Intensive Care Unit, Royal Victoria Hospital, Belfast, Northern Ireland
| | - H J O'Neill
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - G M Ong
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - G Thompson
- Regional Intensive Care Unit, Royal Victoria Hospital, Belfast, Northern Ireland
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - C H Webb
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| | - R McMullan
- Department of Medical Microbiology, Royal Victoria Hospital, Belfast, Northern Ireland
| |
Collapse
|
39
|
Anane S, Khalfallah F. Diagnostic biologique des candidoses systémiques : difficultés et perspectives. ACTA ACUST UNITED AC 2007; 55:262-72. [PMID: 16698196 DOI: 10.1016/j.patbio.2006.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Accepted: 03/22/2006] [Indexed: 11/18/2022]
Abstract
The diagnosis of systemic Candidiasis is difficult to establish and biologic diagnosis raises problems. Blood culture which is the gold standard for the diagnosis of systemic Candidiasis lacks sensitivity and usually takes several days to become positive. Early diagnostic approach is imperative to avoid delays in the initiation for treatment. Therefore, nonculture methods like test for Candida antigen detection, metabolite detection or Candida DNA detection by PCR are being developed for the laboratory diagnosis. Candida derived metabolites and antigens detection lacks sensitivity. A new strategy consisting of the combined detection of mannanemia and an antibody response was developed. The combined detection has a high specificity and sensitivity in the diagnosis of invasive candidiasis. The results of tests for the detection of yeast DNA by PCR obtained recently are promising in terms of sensitivity, specificity and identification of species of Candida.
Collapse
Affiliation(s)
- S Anane
- Département de parasitologie, faculté de médecine de Tunis, 15, rue Djebel-Lakhdar, 1007 La-Rabta, Tunisie.
| | | |
Collapse
|
40
|
Xiang H, Xiong L, Liu X, Tu Z. Rapid simultaneous detection and identification of six species Candida using polymerase chain reaction and reverse line hybridization assay. J Microbiol Methods 2007; 69:282-7. [PMID: 17337309 DOI: 10.1016/j.mimet.2007.01.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 01/18/2007] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
The aim of this study was to develop and evaluate PCR based reverse line blot (RLB) hybridization assay for rapid detection of the most common Candida isolates from clinical specimens. A pair of universal primers targeting the ITS2 region of the gene from 28S rRNA to 5.8S rRNA was designed for PCR amplification of DNA from 6 Candida species (C. albicans, C. tropicalis, C. krusei, C. glabrata, C. parapsilosis, C. dubliniensis), the reverse primer was biotin labeled. PCR products, which were 302-441 bp length, were hybridized with 6 specific oligonucleotides probes immobilized on a nylon membrane. These 6 probes proved specific (they hybridized with only their target molecules). The assay was shown to be sensitive in detecting yeast to a concentration of 10 CFU/ml. This method was used to test 100 isolates and 200 vaginal swabs. The results agreed with those of culture for all but 3 of 100 isolates. Sequencing was performed on these 3 samples and confirmed that the culture results were inaccurate. Our results show the PCR-RLB positive rate (49%) is higher than culture (39%) and smear microscopic screening (27%) (P<0.05). In conclusion, the PCR/RLB developed in this study is specific and offers increased sensitivity compared to culture for the detection of Candida species in swab specimens. Moreover, the improved detection of cases of polycandidal candidiasis is advantageous.
Collapse
Affiliation(s)
- Huaguo Xiang
- Institute of Molecular Biology, Center for Preventive and Control of Sexually Transmitted Disease, Shenzhen Chronic Disease Hospital, 2021 Buxin Road, Shenzhen City, Guangdong Province, 518020 People's Republic of China
| | | | | | | |
Collapse
|
41
|
Medeiros EAS, Lott TJ, Colombo AL, Godoy P, Coutinho AP, Braga MS, Nucci M, Brandt ME. Evidence for a pseudo-outbreak of Candida guilliermondii fungemia in a university hospital in Brazil. J Clin Microbiol 2007; 45:942-7. [PMID: 17229862 PMCID: PMC1829142 DOI: 10.1128/jcm.01878-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fungal infections due to Candida species represent an important cause of nosocomial bloodstream infections. We report a large pseudo-outbreak of Candida guilliermondii fungemia that occurred in a university hospital in Brazil. C. guilliermondii was identified in 64 (43%) of the 149 blood samples drawn between June 2003 and July 2004. The samples were from patients in different wards of the hospital but concentrated in pediatric units. None of the patients had clinical signs of fungemia, and observational analysis revealed errors in the collection of blood samples. During the investigation of the pseudo-outbreak, C. guilliermondii was isolated from environmental surfaces and from the skin and nails of members of the nursing team. Through a subtyping analysis it was found that some of the nonpatient isolates were highly related to the patient isolates, and all the patient isolates were highly related. This is consistent with the hypothesis that the pseudo-outbreak was from a limited number of common sources. The adoption of intervention measures was effective in resolving the outbreak, supporting the hypothesis that the outbreak was due to poor techniques of drawing blood samples for culture.
Collapse
Affiliation(s)
- Eduardo Alexandrino Servolo Medeiros
- Hospital Infection Program, Division of Infectious Diseases, Federal University of São Paulo, Rua Napoleao de Barros, 690, Segundo Andar, São Paulo, Brazil 04024002.
| | | | | | | | | | | | | | | |
Collapse
|
42
|
|
43
|
Galán A, Veses V, Murgui A, Casanova M, Martínez JP. Rapid PCR-based test for identifying Candida albicans by using primers derived from the pH-regulated KER1 gene. FEMS Yeast Res 2006; 6:1094-100. [PMID: 17042759 DOI: 10.1111/j.1567-1364.2006.00114.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A PCR-based method in combination with a simple, reliable and inexpensive DNA extraction procedure for rapid detection of Candida albicans clinical isolates is described here. The extraction protocol is based on a combination of chemical (NaOH and detergents) and physical (boiling) treatments, thus avoiding many of the problems inherent in the currently available DNA extraction protocols (basically the use of expensive and/or toxic chemical reagents), and may be useful for daily clinical routine. The PCR-based system described here uses a single pair of primers (SC1F and SC1R) deduced from the C. albicans-specific KER1 gene sequence. These primers amplify a 670-bp fragment of the KER1 gene. All the clinical C. albicans isolates generated the expected 670-bp amplicon. Other non-albicans Candida species, including the azole-resistant C. krusei and C. glabrata, and the very closely related C. dubliniensis, failed to amplify any DNA fragment. The PCR results reported here suggest that amplification with SC1F and SC1R primers is species specific and, consequently, may be useful for specifically identifying C. albicans strains.
Collapse
Affiliation(s)
- Amparo Galán
- Banco de líneas celulares, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | | | | | | |
Collapse
|
44
|
Mirhendi H, Makimura K, Khoramizadeh M, Yamaguchi H. A one-enzyme PCR-RFLP assay for identification of six medically important Candida species. ACTA ACUST UNITED AC 2006; 47:225-9. [PMID: 16940958 DOI: 10.3314/jjmm.47.225] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Early identification of Candida isolates to the species level is necessary for effective antifungal therapy, and can also facilitate control of hospital infections. Phenotype-based methods for identifying Candida species are often difficult and time-consuming. Molecular biological techniques provide a useful alternative approach. In the present study, the ITS1-5.8S-ITS2 regions of fungal rRNA genes were amplified with universal primers in 20 standard strains. Digestion of the PCR products with one restriction enzyme, MspI, allowed discrimination of medically important Candida species, including C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, and C. guilliermondii. Using this method, we successfully identified 137 clinical isolates of Candida. Among them, C. albicans was identified as the most common species, followed by C. parapsilosis, C. tropicalis, C. glabrata, C. krusei, and C. guilliermondii. This method is a simple, rapid, and cost-effective method for differentiation between species that is applicable in clinical laboratories.
Collapse
Affiliation(s)
- Hossein Mirhendi
- Department of Medical Parasitology and Mycology, School of Public Health and Institute of Public Health Researches (Esfahan Center), Tehran University of Medical Sciences, Tehran, Iran
| | | | | | | |
Collapse
|
45
|
Leaw SN, Chang HC, Sun HF, Barton R, Bouchara JP, Chang TC. Identification of medically important yeast species by sequence analysis of the internal transcribed spacer regions. J Clin Microbiol 2006; 44:693-9. [PMID: 16517841 PMCID: PMC1393093 DOI: 10.1128/jcm.44.3.693-699.2006] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infections caused by yeasts have increased in previous decades due primarily to the increasing population of immunocompromised patients. In addition, infections caused by less common species such as Pichia, Rhodotorula, Trichosporon, and Saccharomyces spp. have been widely reported. This study extensively evaluated the feasibility of sequence analysis of the rRNA gene internal transcribed spacer (ITS) regions for the identification of yeasts of clinical relevance. Both the ITS1 and ITS2 regions of 373 strains (86 species), including 299 reference strains and 74 clinical isolates, were amplified by PCR and sequenced. The sequences were compared to reference data available at the GenBank database by using BLAST (basic local alignment search tool) to determine if species identification was possible by ITS sequencing. Since the GenBank database currently lacks ITS sequence entries for some yeasts, the ITS sequences of type (or reference) strains of 15 species were submitted to GenBank to facilitate identification of these species. Strains producing discrepant identifications between the conventional methods and ITS sequence analysis were further analyzed by sequencing of the D1-D2 domain of the large-subunit rRNA gene for species clarification. The rates of correct identification by ITS1 and ITS2 sequence analysis were 96.8% (361/373) and 99.7% (372/373), respectively. Of the 373 strains tested, only 1 strain (Rhodotorula glutinis BCRC 20576) could not be identified by ITS2 sequence analysis. In conclusion, identification of medically important yeasts by ITS sequencing, especially using the ITS2 region, is reliable and can be used as an accurate alternative to conventional identification methods.
Collapse
Affiliation(s)
- Shiang Ning Leaw
- Institute of Biomedical Engineering, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan, Republic of China
| | | | | | | | | | | |
Collapse
|
46
|
Playford EG, Kong F, Sun Y, Wang H, Halliday C, Sorrell TC. Simultaneous detection and identification of Candida, Aspergillus, and Cryptococcus species by reverse line blot hybridization. J Clin Microbiol 2006; 44:876-80. [PMID: 16517870 PMCID: PMC1393088 DOI: 10.1128/jcm.44.3.876-880.2006] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report on a reverse line blot (RLB) assay, utilizing fungal species-specific oligonucleotide probes to hybridize with internal transcribed spacer 2 region sequences amplified using a nested panfungal PCR. Reference and clinical strains of 16 Candida species (116 strains), Cryptococcus neoformans (five strains of Cryptococcus neoformans var. neoformans, five strains of Cryptococcus neoformans var. grubii, and six strains of Cryptococcus gatti), and five Aspergillus species (68 strains) were all correctly identified by the RLB assay. Additional fungal species (16 species and 26 strains) not represented on the assay did not exhibit cross-hybridization with the oligonucleotide probes. In simulated clinical specimens, the sensitivity of the assay for Candida spp. and Aspergillus spp. was 10(0.5) cells/ml and 10(2) conidia/ml, respectively. This assay allows sensitive and specific simultaneous detection and identification of a broad range of fungal pathogens.
Collapse
Affiliation(s)
- E Geoffrey Playford
- Centre for Infectious Diseases and Microbiology, Institute of Clinical Pathology and Medical Research, Westmead Hospital, New South Wales, Australia.
| | | | | | | | | | | |
Collapse
|
47
|
Neppelenbroek KH, Campanha NH, Spolidorio DMP, Spolidorio LC, Seó RS, Pavarina AC. Molecular fingerprinting methods for the discrimination between C. albicans and C. dubliniensis. Oral Dis 2006; 12:242-53. [PMID: 16700733 DOI: 10.1111/j.1601-0825.2005.01189.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Opportunistic fungal pathogens are becoming increasingly important causes of both community-acquired and nosocomial infections. The most important fungal pathogens are yeast species belonging to the genus Candida. These species show differences in levels of resistance to antifungal agents and mortality. Consequently, it is important to correctly identify the causative organism to the species level. Identification of Candida dubliniensis in particular remains problematic because of the high degree of phenotypic similarity between this species and Candida albicans. However, as the differences between both are most pronounced at the genetic level, several studies have been conducted in order to provide a specific and rapid identification fingerprinting molecular test. In most candidal infectious, no single DNA fingerprinting technique has evolved as a dominant method, and each method has its advantages, disadvantages and limitations. Moreover, the current challenge of these techniques is to compile standardized patterns in a database for interlaboratory use and future reference. This review provides an overview of most common molecular fingerprinting techniques currently available for discrimination of C. albicans and C. dubliniensis.
Collapse
Affiliation(s)
- K H Neppelenbroek
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, São Paulo State University, São Paulo, Brazil
| | | | | | | | | | | |
Collapse
|
48
|
Marot-Leblond A, Beucher B, David S, Nail-Billaud S, Robert R. Development and evaluation of a rapid latex agglutination test using a monoclonal antibody to identify Candida dubliniensis colonies. J Clin Microbiol 2006; 44:138-42. [PMID: 16390961 PMCID: PMC1351948 DOI: 10.1128/jcm.44.1.138-142.2006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cell components of the dimorphic pathogenic fungus Candida dubliniensis were used to prepare monoclonal antibodies (MAbs). One MAb, designated 12F7-F2, was shown by indirect immunofluorescence to be specific for a surface antigen of Candida dubliniensis yeast cells. No reactivity was observed with other fungal genera or with other Candida species, including Candida albicans, that share many phenotypic features with C. dubliniensis. The use of different chemical and physical treatments for cell component extraction suggested that the specific epitope probably resides on a protein moiety absent from C. albicans. However, we failed to identify the target protein by Western blotting, owing to its sensitivity to heat and sodium dodecyl sulfate. MAb 12F7-F2 was further used to develop a commercial latex agglutination test to identify C. dubliniensis colonies (Bichro-dubli Fumouze test; Fumouze Diagnostics). The test was validated on yeast strains previously identified by PCR and on fresh clinical isolates; these included 46 C. dubliniensis isolates, 45 C. albicans isolates, and other yeast species. The test had 100% sensitivity and specificity for C. dubliniensis isolated on Sabouraud dextrose, CHROMagar Candida, and CandiSelect media and 97.8% sensitivity for C. dubliniensis grown on Candida ID medium. The test is rapid (5 min) and easy to use and may be recommended for routine use in clinical microbiology laboratories and for epidemiological investigations.
Collapse
Affiliation(s)
- Agnes Marot-Leblond
- Groupe d'Etude des Interactions Hôte-Parasite, UPRES EA 3142, UFR des Sciences Pharmaceutiques et d'Ingénierie de la Santé, Angers, France.
| | | | | | | | | |
Collapse
|
49
|
De Vos MM, Cuenca-Estrella M, Boekhout T, Theelen B, Matthijs N, Bauters T, Nailis H, Dhont MA, Rodriguez-Tudela JL, Nelis HJ. Vulvovaginal candidiasis in a Flemish patient population. Clin Microbiol Infect 2006; 11:1005-11. [PMID: 16307555 DOI: 10.1111/j.1469-0691.2005.01281.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Increased resistance to fluconazole has been reported in oral, oesophageal and urinary Candida isolates, but this has not been observed commonly in genital tract isolates. The rate of isolation of Candida spp. and their susceptibility to amphotericin B, flucytosine and azoles were determined in a number of clinical practices in the city of Ghent, Belgium. Patients with symptomatic vulvovaginal candidiasis (VVC) were treated with fluconazole, and the mycological and clinical outcomes were evaluated. Isolates were identified as Candida albicans (78.6%), Candida guilliermondii (17.3%), Candida glabrata (2.6%) and Candida dubliniensis (1.3%). The rates of mycological and clinical cures were 79.5% and 100%, respectively. Women with recurrent VVC were infected more frequently by non-albicans Candida spp., but no association was found between the use of antifungal agents and the presence of non-albicans spp. In-vitro resistance to fluconazole was not detected, even among subsequent Candida isolates from nine patients for whom mycological cure was not achieved.
Collapse
Affiliation(s)
- M M De Vos
- Laboratory for Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Beh AL, Fleet GH, Prakitchaiwattana C, Heard GM. Evaluation of molecular methods for the analysis of yeasts in foods and beverages. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2006; 571:69-106. [PMID: 16408594 DOI: 10.1007/0-387-28391-9_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Affiliation(s)
- Ai Lin Beh
- Food Science and Technology, School of Chemical Engineering and Industrial Chemistry, University of New South Wales, Sydney, Australia
| | | | | | | |
Collapse
|