Analysis of tests used to differentiate Trichophyton rubrum from Trichophyton mentagrophytes

Abstract

Differential identification of Trichophyton rubrum and Trichophyton mentagrophytes was evaluated by using the standard in vitro hair perforation test as a criterion for identification and comparing its effectiveness with that of nine other tests used to differentiate these two taxa. Correlation and multiple regression analysis showed that no single test or combination of these tests was able to make the differentiation as effectively as the standard in vitro hair perforation test. Using relative error analysis, we suggest an identification scheme based upon selective utilization of potato-carrot agar for sporulation and the standard in vitro hair perforation test. Using potato-carrot agar for development of typical microconidia on each of the nonsporulating primary isolates and subsequently performing the standard in vitro hair perforation test only on those isolates that failed to produce spores on potato-carrot medium, we showed that this combination scheme provides more expedient results, without any sacrifice in reliability, than

Tiefe Trichophytie bei Tinea corporis

“…Anschließend werden einige Tropfen einer wässrigen Hefeextrakt-Lösung hinzugegeben und schließlich Myzel aus einer Reinkultur des zu untersuchenden Dermatophyten. Nach 2-4 Wochen bilden sich bei positivem Nachweis zapfen-oder keilförmige Hohlräume, die Haarperforationsorgane, welche lichtmikroskopisch nachweisbar sind [3].…”

Differentiation between Trichophyton mentagrophytes and T. rubrum by sorbitol assimilation

“…All T. mentagrophytes strains were positive and all T. (23,31). The advantage of using the API 20C system as a complement to studies of morphology is that the assimilation results are available in 7 days, in contrast to the 28 days needed by T. rubrum for a negative hair perforation test.…”