title: A sensitive and a rapid multiplex polymerase chain reaction for the identification of Candida species in concentrated oral rinse specimens in patients with diabetes.
abstract: OBJECTIVE
  Oral candidiasis is being frequently recognized in patients with diabetes, and is associated with multiple pathogens including Candida albicans, Candida parapsilosis, Candida glabrata and Candida tropicalis. The aim of this study was to evaluate a usefulness of a Multiplex Polymerase Chain Reaction as a rapid diagnostic tool for identification of four oral Candida pathogens in patients with diabetes.
  
  
  METHODS
  A multiplex PCR was optimized to identify four Candida species in concentrated oral rinse samples. Common reverse primer, ITS4 and four species-specific forward primers targeting ITS1 and ITS2 regions of yeast genome were used. Species-specific single amplicon were detected by agarose gel electrophoresis. Performance efficacy of multiplex PCR was compared with phenotypic identification.
  
  
  RESULTS
  Out of 100 oral rinse samples, 72 were culture positive and of these 43 were at risk of oral Candida infection (>600cfu/ml). Multiple Candida species including C. albicans, C. parapsilosis and C. tropicalis were identified in 22 samples which had risk of oral Candida infection. In total, 85 patients were positive for Candida by multiplex PCR and of them 49 had multiple Candida species. All 43 colonized specimens were also positive by multiplex PCR. C. albicans was the most predominant organism (75/85) followed by C. parapsilosis (47/85), C. tropicalis (17/85) and C. glabrata (6/85). In specimens with multiple species, the two most common organisms were C. albicans and C. parapsilosis. Multiplex PCR yielded a sensitivity of 10 Candida cells/ml of oral rinse sample.
  
  
  CONCLUSIONS
  Multiplex PCR is found to be rapid, sensitive and specific than phenotypic identification methods in discriminating multiple Candida species in oral rinse specimens.
authors.affiliation: a Department of Microbiology, Faculty of Medical Sciences , University of Sri Jayewardenepura , Nugegoda , Sri Lanka.
authors.forename: Asanga
authors.initials: A
authors.lastname: Sampath
authors.affiliation: a Department of Microbiology, Faculty of Medical Sciences , University of Sri Jayewardenepura , Nugegoda , Sri Lanka.
authors.forename: Manjula
authors.initials: M
authors.lastname: Weerasekera
authors.affiliation: a Department of Microbiology, Faculty of Medical Sciences , University of Sri Jayewardenepura , Nugegoda , Sri Lanka.
authors.forename: Chinthika
authors.initials: C
authors.lastname: Gunasekara
authors.affiliation: a Department of Microbiology, Faculty of Medical Sciences , University of Sri Jayewardenepura , Nugegoda , Sri Lanka.
authors.forename: Ayomi
authors.initials: A
authors.lastname: Dilhari
authors.affiliation: b Diabetes and Endocrinology Unit , Colombo South Teaching Hospital , Dehiwala , Sri Lanka.
authors.forename: Uditha
authors.initials: U
authors.lastname: Bulugahapitiya
authors.affiliation: a Department of Microbiology, Faculty of Medical Sciences , University of Sri Jayewardenepura , Nugegoda , Sri Lanka.
authors.forename: Neluka
authors.initials: N
authors.lastname: Fernando
mesh_terms: D002175:Candida / Q000302:isolation & purification*; D002176:Candida albicans / Q000302:isolation & purification; D041221:Candida glabrata / Q000302:isolation & purification; D041022:Candida tropicalis / Q000302:isolation & purification; D002180:Candidiasis, Oral / Q000382:microbiology*; D015169:Colony Count, Microbial; D004271:DNA, Fungal; D003924:Diabetes Mellitus, Type 2 / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D009067:Mouthwashes; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D004271:DNA, Fungal; D009067:Mouthwashes
keywords: Multiplex PCR; Sri Lanka; concentrated oral rinse; oral candidiasis