• 1

    Evans EGV: Causative pathogens in onychomycosis and the possibility of treatment resistance: a review. J Am Acad Dermatol 38: S32, 1998.

  • 2

    Gupta AK, Jain HC, Lynde C, et al: Prevalence and epidemiology of onychomycosis in patients visiting physicians' offices: a multicenter Canadian survey of 15000 patients. J Am Acad Dermatol 43: 244, 2000.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3

    Welsh O, Vera-Cabrera L, Welsh E: Onychomycosis. Clin Dermatol 28: 151, 2010.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 4

    Vander Straten MR, Balkis MM, Ghannoum MA: The role of nondermatophyte molds in onychomycosis: diagnosis and treatment. Dermatol Ther 15: 89, 2002.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5

    Moreno G, Arenas R: Other fungi causing onychomycosis. Clin Dermatol 28: 160, 2010.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 6

    Summerbell RC: Epidemiology and ecology of onychomycosis. Dermatology 194 (Suppl 1): 32, 1997.

  • 7

    Evans EG: Causative pathogens in onychomycosis and the possibility of treatment resistance: a review. J Am Acad Dermatol 38: S32, 1998.

  • 8

    Bontems O, Hauser PM, Monod M: Evaluation of a polymerase chain reaction-restriction fragment length polymorphism assay for dermatophyte and nondermatophyte identification in onychomycosis. Br J Dermatol 161: 791, 2009.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 9

    Ebihara M, Makimura K, Sato K, et al: Molecular detection of dermatophytes and nondermatophytes in onychomycosis by nested polymerase chain reaction based on 28S ribosomal RNA gene sequence Br J Dermatol 161: 1038, 2009.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 10

    Gupta AK, Zaman M, Singh J: Fast and sensitive detection of Trichophyton rubrum DNA from the nail samples of patients with onychomycosis by a double-round polymerase chain reaction-based assay. Br J Dermatol 157: 698, 2007.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 11

    Arabatzis M, Bruijnesteijn van Coppenraet LE, Kuijper EJ, et al: Diagnosis of common dermatophyte infections by a novel multiplex real-time polymerase chain reaction detection/identification scheme. Br J Dermatol 157: 681, 2007.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 12

    Monod M, Bontems O, Zaugg C, et al: Fast and reliable PCR/sequencing/RFLP assay for identification of fungi in onychomycosis. J Med Microbiol 55: 1211, 2006.

  • 13

    Kardjeva V, Summerbell R, Kantardjiev T, et al: Forty-eight-hour diagnosis of onychomycosis with subtyping of Trichophyton rubrum strains. J Clin Microbiol 4: 1419, 2006.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14

    Machouart-Dubach M, Lacroix C, Feuilhade De Chauvin M, et al: Rapid discrimination among dermatophytes, Scytalidium spp., and other fungi with a PCR-restriction fragment length polymorphism ribotyping method. J Clin Microbiol 39: 685, 2001.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15

    Jackson CJ, Barton RC, Evans EG: Species identification and strain differentiation of dermatophyte fungi by analysis of ribosomal-DNA intergenic spacer regions. J Clin Microbiol 37: 931, 1999.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 16

    Menotti J, Machouart M, Benderdouche C, et al: Polymerase chain reaction for diagnosis of dermatophyte and Scytalidium spp. onychomycosis. Br J Dermatol 151: 518, 2004.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17

    Verrier J, Pronina M, Peter C, et al: Identification of infectious agents in onychomycoses by PCR-terminal restriction fragment length polymorphism. J Clin Microbiol 50: 553, 2012.

    • Crossref
    • PubMed
    • Web of Science
    • Search Google Scholar
    • Export Citation
  • 18

    Gupta AK, Drummond-Main C, Cooper EA, et al: Systematic review of nondermatophyte mold onychomycosis: diagnosis, clinical types, epidemiology, and treatment. J Am Acad Dermatol 66: 494, 2012.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 19

    Gupta AK, Jain HC, Lynde CW, et al: Prevalence and epidemiology of unsuspected onychomycosis in patients visiting dermatologists' offices in Ontario, Canada: a multicenter survey of 2001 patients. Int J Dermatol 36: 783, 1997.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20

    Gupta AK, Ryder JE, Baran R, et al: Non-dermatophyte onychomycosis. Dermatol Clin 21: 257, 2003.

  • 21

    Ninet B, Jan I, Bontems O, et al: Molecular identification of Fusarium species in onychomycoses. Dermatology 210: 21, 2005.

Molecular Determination of Mixed Infections of Dermatophytes and Nondermatophyte Molds in Individuals with Onychomycosis

Aditya K. Gupta MD, PhD, FRCP(C)1,2 and Kerry-Ann Nakrieko PhD2
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  • 1 Division of Dermatology, Department of Medicine, University of Toronto, Toronto, ON, Canada.
  • | 2 Mycology and Molecular Biology Sections, Mediprobe Research Inc, London, ON, Canada.
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Background

Reports of mixed infections with nondermatophyte molds (NDMs) and dermatophytes in onychomycosis are rare, possibly owing to the inhibition of NDM growth during traditional culture. We sought to determine the prevalence of mixed infections in onychomycosis using molecular identification.

Methods

Molecular analyses were used to identify infecting organisms directly from at least two serial great toenail samples from each of the 44 patients.

Results

Mixed infections were present in 41% of the patients (18 of 44). A single coinfecting NDM was the most common mixed infection and was detected in 34% of patients with onychomycosis (15 of 44), with Fusarium oxysporum present in 14% (6 of 44), Scopulariopsis brevicaulis in 9% (4 of 44), Acremonium spp in 2% (1 of 44), Aspergillus spp in 4.5% (2 of 44), and Scytalidium spp in 4.5% (2 of 44). Mixed infections with two NDMs were found in 7% of patients (3 of 44).

Conclusions

Mixed onychomycosis infections may be more prevalent than previously reported.

Corresponding author: Aditya K. Gupta, Mediprobe Research Inc, 645 Windermere Rd, London, ON Canada, N5X 2P1. (E-mail: agupta@mediproberesearch.com)