Comparative Study for Methods for Diagnosing Onychomycosis

Background : Onychomycosis is very common nail problem, so an in xpensive, quick and sensitive test is essential for screening nail specimens. Recently, there is a report of new method for diagnosing onychomycosis u.;ing KOH treated nail clippings which vri then crushed and finally stained with periodic acid-Schifft(PAS) stain (KONCPA). Objective : We evaluate the susefulness of the new methods using KOH treated nail clippings and nail debris which were then crushed and finally stained with FS (KONPA) or chlorazol black E(KONBE), for the diagriosis of onychomycosis. Methods : We compare different methods for diagnosing onychonycisis such as KOH stains, fungal cultures, histologic evaluat.ion, SEM, KONCPA, KONBE, and KOHJPA. Results : KONPA was proved to be more effective indentifying uiigal hyphae in comparison with conventional KOH nail scraping preparation, fungal culture, and FONBE. The positive rates of each method were 74%, 46%, 43%, and 63%, respectively. Also, KENPA proved to be more rapid and easy to perform in cotnparison to the histologic evaluation of tiail clippings and SEM. Conclusion : KONPA is a sensitive, quick, and readily available teled for use in clinical settings in cases that are highy siispected to be onychomycosis clinicaly, but show negative results using conventional methodsprohibitio