Classification of dermatophytes, infections caused by some 10 species of them isolated in the past and change of dermatophytoses since 1924 in Korea were briefly reviewed. Because, especially in recent years, infections due to zoophilic organisms have been noted to increase in frequency, a role of animals in human ringworm should be clarified. In addition, taking account of ever increasing international exchange of men and animals, care must be taken to detect and cope with an inflow of foreign species of fungi into our country.
Animals ; Arthrodermataceae ; Classification ; Fungi ; Humans ; Korea* ; Male ; Tinea*

BACKGROUND: Onychomycosis is one of the most common nail disorders, but dermatologists have experienced poor efficacy ol therapy because of incorrect diagnosis. It has been reported that histopathologic evaluation of the nail plate by nail clipping might be a useful supportive method for identification of causative fungi showing higher detection rates. OBJECTIVE: This study was aimed to determine whether histopathologic examination support for identification of causative fungi and whether it increased. The diagnostic sensitivity of onychomycosis even in cases that those fungus culture fail to identify the causative fungi, and to clarify the relative frequency of causative fungi in onychomycosis. METHODS: Histopathologic findings of 218 onychomycotic nail samples, proven by KOH smear, were analyzed and compared with the results of fungus culture. RESULTS: The results were as follows; 1. Histopathologic examination showed higher positive rate (73.9%) than that of fungus culture (35.8%) in identifying the etiologic fungi. 2. The 3 groups of causative fungi confirmed by fungus culture showed morphologically distinguishable characteristics in histopathologic examination: Dermatophytes showed septated long, thin and regular hyphae with or without arthrospores, while Candida sp. showed blastospores, grape-like clusters of regular spores and pseudohyphae. Mold exhibited irregular hyphae with variable width and aggregates of irregular spores. Mixed infections showed the characteristic findings of the corresponding groups at the different sites of the nail samples. 3. Frequency of the causative fungi by fungus culture was 88.5% of dermatophytes, 5.1% of Candida sp. and 6.4% of mold. In histopathologic examination, the frequency was considered as 80.7% of dermatophytes,8.1% of Candida sp.,6.2% of mold and 1.9% of mixed infection. 4. In 42 of 59 samples of T. rubrum and 3 of 10 samples of T. mentagrophytes, hyphae were observed on the ventral and dorsal layer of the nail plate, respectively. In histopathologic sections, 88 of 130 samples of dermatophytes showed fungal element on the ventral layer of the nail plate and all 13 samples of Candida sp. on the subungal keratin layer and ventral layer of the nail plate. CONCLUSION: Histopathologic examination in onychomycosis is considered to be simple, useful supportive method in studying the classification and distribution of causative fungi of onychomycosis and might be included in the routine laboratory tests for making the presumptive diagnosis of causative fungi of onychomycosis. Moreover, we can determine the site of involvement of the fungi in the nail, so we can get useful informations about mixed infections or contaminations
Arthrodermataceae ; Candida ; Classification ; Coinfection ; Diagnosis ; Fungi* ; Hyphae ; Onychomycosis* ; Spores

To establish a simple, sensitive and effective technique for the identification of six common dermatophytes, polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) targeting Topoisomerase II gene were used. The DNA of 6 common dermatophytes was amplified by primer dPsD1 and then primers dPsD2. The products generated by dPsD2 were digested with restriction enzyme Hinc II and Hinf I separately. A DNA fragment of about 3390 bp was amplified by using primer dPsD1 from the genomic DNA of each dermatophyte species. The product of dPsD2 was 2380 bp and the restriction profiles of Hinc II and Hinf I were between 58-1670 bp. By using PCR-RFLP, all of the 6 dermatophytoses were diagnosed to species level and no obvious difference identification between Hinc II and Hinf I. It is concluded that the PCR-RFLP identification of dermatophytes by Hinc II or Hinf I is efficient and rapid in clinical practice.
Arthrodermataceae/*classification ; Arthrodermataceae/genetics ; Arthrodermataceae/*isolation & purification ; DNA Topoisomerases, Type II/genetics ; DNA, Fungal/analysis ; DNA, Fungal/genetics ; Dermatomycoses/*microbiology ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length

BACKGROUND: Onychomycosis is one of the most common nail disorders, and it is necessary of mycologic confirmation to treat correctly. It has been reported that histopathologic evaluation and polymerase chain reaction (PCR) of the nail plate by nail clipping might be a useful supportive method for identification of causative fungi showing higher detection rates. Objective: This study was designed to compare diagnostic efficacy of KOH preparation, fungal culture, histopathologic examination and PCR in onychomycosis. METHODS: Using 60 nail samples from 60 patients with clinically suspected onychomycosis, KOH preparation and fungal culture with nail and subungual tissue was performed. And histopathologic examination with PAS staining and PCR with DNA extracted from paraffin block was performed. RESULTS: The results are summarized as follows: 1. The positive rates of conventional KOH preparation, fungal culture, histopathologic examination and PCR were 87.5%, 8.9%, 87.5% and 83.9%. 2. In histopathologic examination, fungi were distinguished as 3 groups based on Kim and Cho's classification (1997): dermatophytes, Candida sp. and non-dermatophytic mold (NDM). Fifteen of 49 samples are dermatophytes, 1 is Candida sp., and 7 are NDM, 8 are dermatophytes and Candida sp. mixed infections, 18 are dermatophytes and NDM mixed infections. 3. In PCR, 1 of 47 samples is Trichophyton rubrum, 4 are Candida sp. and 39 samples are NDM. CONCLUSION: Histopathologic examination in onychomycosis is considered to be an useful supportive method in diagnosis and identification of causative fungi in onychomycosis.
Arthrodermataceae ; Candida ; Classification ; Coinfection ; Diagnosis* ; DNA ; Fungi ; Humans ; Onychomycosis* ; Paraffin ; Polymerase Chain Reaction* ; Trichophyton

BACKGROUND: The species of dermatophytes have been identified and classified by morphological and biochemical characterization as well as by mating experiments. But these techniques are either time consuming or lacking specificity. Recently molecular analysis has been introduced to the field of medical mycology. OBJECTIVE: We investigated the phylogeny and taxonomy of the dermatophytes using sequence analysis of the ribosomal internal transcribed spacer 1 (ITS1) region. METHODS: 15 species of dermatophytes (6 strains of T. rubrum, 4 strains of T. mentagrophytes subtypes, M. canis, M. gypseum, E. floccosum, T. verrucosum, and T. tonsurans) were cultured on Sabouraud dextrose broth and their DNA was extracted by bead-beating method. Cloning and sequencing of PCR product was done. RESULTS: The size of specific bands among dermatophytes was 340 bp in ITS1 region. Phylogenetic analysis of sequences revealed that 6 strains of T. rubrum showed genetically identical patterns in intraspecies, but subtypes of T. mentagrophytes were different. The other dermatophytes showed different patterns in interspecies. The following taxonomy were so closely related: granular form of T. mentagrophytes and T. tonsurans; powdery form, persicolor form and downy form of T. mentagrophytes; and M. gypseum and E. floccosum. CONCLUSION: The phylogenetic analysis of ITS1 region provided useful information for classification and understanding the evolution of dermatophytes species.
Arthrodermataceae* ; Classification* ; Clone Cells ; Cloning, Organism ; DNA ; Glucose ; Mycology ; Phylogeny* ; Polymerase Chain Reaction ; Sensitivity and Specificity ; Sequence Analysis*

BACKGROUND: The species of dermatophytes have been identified and classified by morphological and biochemical characterization as well as by mating experiments. But these techniques are either time consuming or lacking specificity. Recently molecular analysis has been introduced to the field of medical mycology. OBJECTIVE: We investigated the phylogeny and taxomomy of the dermatophytes using sequence analysis of the chitin synthase 1 (CHS1) gene. METHODS: 15 species of dermatophytes (6 strains of T.rubrum, 4 strains of T. mentagrophytes subtypes, M. canis, M. gypseum, E. floccosum, T. verrucosum, and T. tonsurans) were cultured on Sabouraud dextrose broth and their DNA were extracted by bead-beating method. Cloning and sequencing of PCR product were done. RESULTS: The size of specific bands among dermatophytes was 615 bp in CHS1 gene. Phylogenetic analysis of sequences revealed that 6 strains of T. rubrum showed genetically identical pattern in intraspecies, but subtypes of T. mentagrophytes were different. The other dermatophytes showed different pattern in interspecies. CONCLUSION: The phylogenetic analysis of CHS1 gene provided useful information for classification and understanding the evolution of dermatophytes species.
Arthrodermataceae* ; Chitin Synthase* ; Chitin* ; Classification* ; Clone Cells ; Cloning, Organism ; DNA ; Glucose ; Mycology ; Phylogeny* ; Polymerase Chain Reaction ; Sensitivity and Specificity ; Sequence Analysis*

To find a fast and efficient way of identifying seven common dermatophytes in clinical practice, we used the techniques of polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) targeting Topoisomerase II gene. The DNA of 7 dermatophytes, along with Candida albicans, Aspergillus terreus and Aspergillus flavus were amplified by consensus primer dPsD1. They were then subjected to a second PCR with primers dPsD2 and species-specific primers PsT and PsME separately. 6 of the products generated by dPsD2 were digested with restriction enzyme Hinc II. DNA fragments of 3390 bp and 2380 bp was amplified by using consensus primer dPsD1 and dPsD2 from the genomic DNA of each dermatophyte species separately. By combining the results of the two species-specific primer sets (PsT and PsME), all species of dermatophyte yielded unique sizes-set of PCR products expect for T. mentagrophytes and T. tonsurans. From the restriction profiles of Hinc II, 6 of the 7 dermatophytoses were diagnosed to species level including T. mentagrophytes and T. tonsurans. By combining the results of the PCR and PCR-RFLP, the 7 common dermatophytes can be identified to species level. It is conclude that the multiplex PCR and PCR-RFLP identification targeting the DNA topoisomerase II gene is rapid and efficient.
Arthrodermataceae/classification ; Arthrodermataceae/*isolation & purification ; Aspergillus/*isolation & purification ; Candida albicans/isolation & purification ; DNA Topoisomerases, Type II/genetics ; Dermatomycoses/microbiology ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Trichophyton/*isolation & purification

BACKGROUND: Dermatophytoses are infections of keratinized tissues, that is, the epidermis, hair and nails, caused by a group of specialized fungi, the dermatophytes. Laboratory diagnoses of dermatophytes such as Tricophyton, Microsporum and Epidermophyton are made by microscopic examination and in vitro culture but they are either time consuming of lacking specificity. OBJECTIVE: In order to develop and apply more rapid and precise diagnostic tests for fungal pathogens to facilitate the improved identification of dermatophytes, we investigated random amplified polymorphism DNA for classification and identification of dermatophytes. METHODS: Amplification reactions were performed in volumes of 5011 containing 10mM Tris-HCl(pH 8.3), 50mM KCl, 1.5mM MgCl2, 0.01% (w/v), gelatin, 200mM dNTP mixture, 50pM primer, Taq polymerase (0.025 units/ microliter), DNA 0.001 microgram/microliter. The optimal condition to. PCR was 2 cycles (denaturing 94 degrees C 2min, annealing 33 degrees C 2min, extension 72 degrees C 4min), 40 cycles, and extension (72 degrees C 10min). RESULTS: RAPD showed interspecies polymorphism in but it had identical patterns in intraspecies. CONCLUSION: It was confirmed that RAPD PCR analysis with optimal conditions is a fast, economical and reproducible method for identification and classification of dermatophytes isolates.
Arthrodermataceae* ; Classification* ; Clinical Laboratory Techniques ; Diagnostic Tests, Routine ; DNA* ; Epidermis ; Epidermophyton ; Fungi ; Gelatin ; Hair ; Magnesium Chloride ; Microsporum ; Polymerase Chain Reaction ; Sensitivity and Specificity ; Taq Polymerase ; Tinea

To find a fast and efficient way of identifying seven common dermatophytes in clinical practice, we used the techniques of polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) targeting Topoisomerase II gene. The DNA of 7 dermatophytes, along with Candida albicans, Aspergillus terreus and Aspergillus flavus were amplified by consensus primer dPsD1. They were then subjected to a second PCR with primers dPsD2 and species-specific primers PsT and PsME separately. 6 of the products generated by dPsD2 were digested with restriction enzyme Hinc II. DNA fragments of 3390 bp and 2380 bp was amplified by using consensus primer dPsD1 and dPsD2 from the genomic DNA of each dermatophyte species separately. By combining the results of the two species-specific primer sets (PsT and PsME), all species of dermatophyte yielded unique sizes-set of PCR products expect for T. mentagrophytes and T. tonsurans. From the restriction profiles of Hinc II, 6 of the 7 dermatophytoses were diagnosed to species level including T. mentagrophytes and T. tonsurans. By combining the results of the PCR and PCR-RFLP, the 7 common dermatophytes can be identified to species level. It is conclude that the multiplex PCR and PCR-RFLP identification targeting the DNA topoisomerase II gene is rapid and efficient.
Arthrodermataceae ; classification ; isolation & purification ; Aspergillus ; isolation & purification ; Candida albicans ; isolation & purification ; DNA Topoisomerases, Type II ; genetics ; Dermatomycoses ; microbiology ; Humans ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Trichophyton ; isolation & purification