title: Rapid real-time diagnostic PCR for Trichophyton rubrum and Trichophyton mentagrophytes in patients with tinea unguium and tinea pedis using specific fluorescent probes.
abstract: BACKGROUND
  Trichophyton rubrum and Trichophyton mentagrophytes human-type (synonym, Trichophyton interdigitale (anthropophilic)) are major causative pathogens of tinea unguium. For suitable diagnosis and treatment, rapid and accurate identification of etiologic agents in clinical samples using reliable molecular based method is required.
  
  
  OBJECTIVE
  For identification of organisms causing tinea unguium, we developed a new real-time polymerase chain reaction (PCR) with a pan-fungal primer set and probe, as well as specific primer sets and probes for T. rubrum and T. mentagrophytes human-type.
  
  
  METHODS
  We designed two sets of primers from the internal transcribed spacer 1 (ITS1) region of fungal ribosomal DNA (rDNA) and three quadruple fluorescent probes, one for detection wide range pathogenic fungi and two for classification of T. rubrum and T. mentagrophytes by specific binding to different sites in the ITS1 region. We investigated the specificity of these primer sets and probes using fungal genomic DNA, and also examined 42 clinical specimens with our real-time PCR.
  
  
  RESULTS
  The primers and probes specifically detected T. rubrum, T. mentagrophytes, and a wide range of pathogenic fungi. The causative pathogens were identified in 42 nail and skin samples from 32 patients. The total time required for identification of fungal species in each clinical specimen was about 3h. The copy number of each fungal DNA in the clinical specimens was estimated from the intensity of fluorescence simultaneously.
  
  
  CONCLUSIONS
  This PCR system is one of the most rapid and sensitive methods available for diagnosing dermatophytosis, including tinea unguium and tinea pedis.
authors.affiliation: Teikyo University Institute of Medical Mycology and Genome Research Center, Tokyo, Japan.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Miyajima
authors.forename: Kazuo
authors.initials: K
authors.lastname: Satoh
authors.forename: Takao
authors.initials: T
authors.lastname: Uchida
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamada
authors.forename: Michiko
authors.initials: M
authors.lastname: Abe
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Watanabe
authors.forename: Miho
authors.initials: M
authors.lastname: Makimura
authors.forename: Koichi
authors.initials: K
authors.lastname: Makimura
mesh_terms: D004271:DNA, Fungal / Q000032:analysis; D021903:DNA, Ribosomal Spacer / Q000032:analysis; D005456:Fluorescent Dyes / Q000494:pharmacology*; D018628:Gene Dosage; D006801:Humans; D009262:Nails / Q000382:microbiology; D014009:Onychomycosis / Q000175:diagnosis* / Q000382:microbiology; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D012867:Skin / Q000382:microbiology; D014008:Tinea Pedis / Q000175:diagnosis* / Q000382:microbiology; D014249:Trichophyton / Q000302:isolation & purification*
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D005456:Fluorescent Dyes