A large-scale North American study of fungal isolates from nails: The frequency of onychomycosis, fungal distribution, and antifungal susceptibility patterns

M. A. Ghannoum, R. A. Hajjeh, R. Scher, N. Konnikov, A. K. Gupta, R. Summerbell, S. Sullivan, R. Daniel, P. Krusinski, P. Fleckman, P. Rich, R. Odom, R. Aly, D. Pariser, M. Zaiac, G. Rebell, Jack L Lesher, B. Gerlach, G. F. Ponce-de-Leon, A. GhannoumJ. Warner, N. Isham, B. Elewski

Research output: Contribution to journalArticle

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Background: Onychomycosis, a fungal infection of the nail bed, is responsible for up to 50% of nail disorders. Although several surveys have been conducted in different parts of the world, there have been no multicenter epidemiologic surveys of onychomycosis in North Ameriea. Objective: A 12-center study was undertaken to (1) determine the frequency of onychomycosis, (2) identify organisms recovered from the nails, and (3) determine the antifungal susceptibility of isolates. Methods: A total of 1832 subjects participated in this study and completed a comprehensive questionnaire, and nail clippings were collected for potassium hydroxide examination and culturing. Results: The frequency of onychomycosis, as defined by the presence of septate hyphae on direct microscopy and/or the recovery of a dermatophyte, was found to be 13.8%. In general, the dermatophyte isolates were susceptible to the antifungals tested. Conclusion: Because of the limited number of large-scale studies, the baseline incidence is not firmly established. However, the higher frequency of onychomycosis in this study may confirm the suspected increase in incidence of disease in North America.

Original languageEnglish (US)
Pages (from-to)641-648
Number of pages8
JournalJournal of the American Academy of Dermatology
Issue number4
Publication statusPublished - Jan 1 2000


ASJC Scopus subject areas

  • Dermatology

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