Mentagrophytes - Çukurova Üniversitesi

ABSTRACT
COMPARISION OF IDENTIFICATION METHODS FOR THE
DIFFERENTIATION OF TRICHOPHYTON RUBRUM FROM TRICHOPHYTON
MENTAGROPHYTES
Nowadays a rapid and striking change is observed in the taxonomy of
dermatophytes. They are either re-grouped or re-named, in addition some
varieties remain out of nomenclature giving origin to new species.
The gold standard in laboratory diagnosis is sequencing analysis. But
dermatophyte species are identified at the level of species according to colony
characteristics, microscopic morphologies, growth requirements, physiological and
biochemical characteristics due to infer-structural needs and high cost of
molecular based researches. As changes are observed for a single dermatophyte
species both for its morphology (colony pattern, pigments and growth rate) or
physiology (in vitro hair perforation) and for its genotype (rRNA and mating
patterns); the reliability of the method is questioned.
Many micro-organisms belonging to Trichophyton rubrum complex are
renamed i.e., T. fischeri, T. kanei, T. raubitschekii and similar are identified.
Trichophyton interdigitale, and other micro-organisms pertaining to Trichophyton
mentagrophytes sensu lato are re-classified by sequencing analysis. But one of the
principal problems observed in mycology laboratory is the differentiation of T.
rubrum from T. mentagrophytes using classical diagnostic methods. This study
aimed to discuss the efficacy of morphological, physiological and biochemical
diagnostic tests used in the laboratory identification of micro-organisms pertaining
to both complexes before the current classification, in addition to interrogate their
reliability in routine laboratory practice.
In the study, T. fischeri CBS 100081, T. fluvimunionse CBS 592.68, T. kanei
CBS 289.86, T. kuryangei CBS 422.67, T. kuryangei CBS 517.63, T. kuryangei CBS
518.63, T. pervesii CBS 303.38, T. raubitschekii CBS 202.88, T. raubitschekii CBS
287.86, T. raubitschekii CBS 100084, T. raubitschekii CBS 102856, T. rodhainii CBS
376.49, T. rubrum CBS 302.60, T. rubrum CBS 363.53, T. rubrum CBS 363.62, T.
rubrum CBS 392.58, T. rubrum var. nigricans CBS 100237, T. megninii CBS 389.58,
T. asteroides CBS 424.63, T. langeronii CBS 764.84, T. mentagrophytes CBS 318.56,
T. mentagrophytes var. mentagrophytes CBS 110.65, T. mentagrophytes var.
mentagrophytes CBS 160.66, T. papillosum CBS 347.55, T. quinckeanum CBS
572.75, Arthroderma benhamiae (MT-) CBS 807.72, A. benhamiae (MT+) CBS
808.72, A. simii (MT-) CBS 417.65, A. simii (MT+) CBS 448.65, A. vanbreuseghemii
CBS 428.63 and A. vanbreuseghemii CBS 558.66 obtained from Centraalbureau
voor Schimmelcultures (CBS), Utrecht, the Netherlans were used.
Urease reaction (in broth, in tube-agar and Petri agar), in vitro hair
perforation test (blond child hair, sheep and goat hair), growth in corn-meal agar
and bromcresol purple-milk solids-glucose agar (BCPMSG), Tween opacity test,
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