Assessment of a Pan-Dermatophyte nested-PCR Compared With Conventional Methods for Direct Detection and Identification of Dermatophytosis Agents in Animals

Mycoses. 2018 Nov;61(11):837-844. doi: 10.1111/myc.12821. Epub 2018 Jul 11.

Abstract

Conventional direct microscopy with potassium hydroxide (KOH) and culture were found to lack the ability to establish a fast and specific diagnosis of dermatophytosis. A pan-dermatophyte nested-PCR assay was developed using a novel primer pair targeting the translation elongation factor 1-α (Tef-1α) sequences for direct detection and identification of most veterinary relevant dermatophytes in animal samples suspected to dermatophytosis. A total of 140 animal skin and hair samples were subjected to direct microscopy, culture, and ITS-RFLP/ITS-sequencing of culture isolates for the detection and identification of dermatophytosis agents. Nested-PCR sequencing was performed on all the extracted DNAs using a commercial kit after dissolving the specimens by mechanical beating. Nested-PCR was positive in 90% of samples, followed by direct microscopy (85.7%) and culture (75%). The degree of agreement between nested-PCR and direct microscopy (94.4%) was higher than with culture (83.3%). In 105 culture-positive cases, the measures of agreement for the identification of dermatophytosis agents were as follows: 100% between nested-PCR sequencing and ITS-RFLP/ITS-sequencing and 63.8% between nested-PCR sequencing and culture. The developed nested-PCR was faster as well as more sensitive and specific than conventional methods for detection and identification of dermatophytes in clinical samples, which was particularly suitable for epidemiological studies.

Keywords: Tef-1α; animal; dermatophytosis; nested-PCR.

Publication types

  • Comparative Study

MeSH terms

  • Animal Diseases / diagnosis
  • Animal Diseases / microbiology*
  • Animals
  • Arthrodermataceae / classification
  • Arthrodermataceae / genetics
  • Arthrodermataceae / isolation & purification*
  • Cats
  • Cattle
  • DNA, Fungal / genetics
  • Dogs
  • Goats
  • Horses
  • Microscopy / methods*
  • Microscopy / veterinary
  • Polymerase Chain Reaction / methods*
  • Polymerase Chain Reaction / veterinary
  • Sensitivity and Specificity
  • Sheep
  • Tinea / diagnosis
  • Tinea / microbiology
  • Tinea / veterinary*

Substances

  • DNA, Fungal

Associated data

  • GENBANK/JN134120
  • GENBANK/KM678151
  • GENBANK/JN134125
  • GENBANK/KM678052
  • GENBANK/JN134140
  • GENBANK/KM678208
  • GENBANK/KT155781
  • GENBANK/KM678170
  • GENBANK/JN134133
  • GENBANK/KM678196
  • GENBANK/JN134130
  • GENBANK/KM678161
  • GENBANK/JN134144
  • GENBANK/KM678207
  • GENBANK/JN134095
  • GENBANK/KM678199
  • GENBANK/DQ860795
  • GENBANK/KM678084
  • GENBANK/KM678049
  • GENBANK/Z98002
  • GENBANK/JN133985
  • GENBANK/KM678178
  • GENBANK/JN133989
  • GENBANK/KM678180
  • GENBANK/JN134101
  • GENBANK/KT155643
  • GENBANK/KM678075
  • GENBANK/EF043279
  • GENBANK/JN134108
  • GENBANK/KM678061
  • GENBANK/JN134093
  • GENBANK/KM678198
  • GENBANK/KT155934
  • GENBANK/KM678104
  • GENBANK/KT155890
  • GENBANK/KM678090
  • GENBANK/KT155779
  • GENBANK/JN134092
  • GENBANK/KM678197