Classification and Typing of Trichophyton mentagrophytes Isolated from a Korean Population / 대한의진균학회지

BACKGROUND: Trichophyton mentagrophytes complex is a heterogeneous group. A new classification, based on molecular biology, has replaced the one based on morphology, physiology, and mating behavior. OBJECTIVE: T. mentagrophytes isolates from Korean patients were classified using the new method and compared with the classic classification. METHODS: During 2010-2011, fungal isolates were collected at the Catholic skin clinic from 562 patients infected with T. mentagrophytes; clinical characteristics were reviewed. Patients were divided into four groups based on the morphological characteristics of the isolates. Thirty-four strains of T. mentagrophytes were randomly selected from the four groups for mycological and molecular biology analyses, including analyses of morphological characteristics, ribosomal DNA (rDNA) internal transcribed spacer (ITS) sequence, and rDNA nontranscribed spacer (NTS) typing. RESULTS: Among the 562 isolates, persicolor (41.6%) was the most common strain type, followed by the powdery (38.4%), downy (11.2%), and granular (8.7%) types. The granular type differed from the other three with respect to the isolation site, patient's age, seasonal variation, and microscopic characteristics. Among the selected 34 strains, the microscopic characteristics varied for each strain. The powdery, persicolor, and downy types had ITS sequences identical to those of the anthropophilic T. interdigitale/A. vanbreuseghemii. The ITS sequence of granular type was similar to that of zoophilic T. interdigitale/A. vanbreuseghemii. The granular type had different NTS types than the other types did. CONCLUSION: The T. mentagrophytes strains isolated were classified as T. interdigitale/A. vanbreuseghemii; the majority (91.7%) was anthropophilic and 8.3% were zoophilic and granular type.

Nucleotide Sequence of Internal Transcribed Spacer 1 of Trichophyton mentagrophytes Isolated from Human and Animals / 대한피부과학회지

BACKGROUND: Trichophyton mentagrophytes is a complex species and 3 perfect states, Arthroderma benhamiae, A. vanbreuseghemii, and A. simii have been described. In Korea and Japan, all of the isolates of T. mentagrophytes of which the perfect states determined were known as A. vanbreuseghemii till recently. However, in Japan, one isolate from a monkey was reported as A. simii and several strains from rabbits or patients were A. benhamiae. Therefore, it is necessary to confirm the existence of A. simii or A. benhamiae in Korea. OBJECTIVES: We performed this study to determine the teleomorphs of 19 strains of T. mentagrophytes isolated from Korean patients infected from pets and 4 from the skin lesions of rabbits. METHODS: DNA sequences of internal transcribed spacer 1 (ITS1) area of the 23 isolates and 3 reference strains were determined and matched with the data registered in GenBank nucleotide sequence database. RESULTS: The sequencing data of 22 isolates were very similar to those of A. vanbreuseghemii and 1 to T. mentagrophytes var. interdigitale respectively. CONCLUSION: Although all of the clinical isolates were related with A. vanbreuseghemii in this study, the possibility of the existence of A. simii and A. benhamiae in Korea is still high and further study is needed.