Species distribution of the main aetiologic agents causing skin dermatophytosis in Colombian patients: A 23-year experience at a Mycological Reference Center.

BACKGROUND: Dermatophytosis is one of the most frequent superficial mycoses in the world. MAIN AIM: To describe the cases of skin dermatophytosis and its main aetiologic agents in patients referred to a Mycological Reference Laboratory in Medellín, Colombia. METHODS: A retrospective study was carried out with records of patients referred between 1994 and 2016 to the Corporación para Investigaciones Biológicas (CIB), Medellín-Colombia, because of clinical suspicion of skin dermatophytosis. RESULTS: Of a total of 5628 clinical records of patients with suspicion of skin dermatophytosis analysed, 2780 (49.4%) had a proven or probable dermatophytosis diagnosis, 2774 cultures were performed, and aetiologic agents were isolated in 2576 samples (92.9%). The most frequently isolated aetiologic agents were Trichophyton rubrum (44.3%), followed by Trichophyton mentagrophytes complex (33.3%), Epidermophyton floccosum (12.4%), Nannizzia gypseum complex (5.7%, formerly Microsporum gypseum), Microsporum canis (3.5%) and Trichophyton tonsurans (0.8%). The most frequent clinical forms were tinea pedis (72.7%) and tinea corporis (12.7%). In addition, a group of patients (0.9%) developed mixed infections by two dermatophyte agents and another (4.1%) developed infections in more than one anatomical site. CONCLUSIONS: The results of the present study are coherent with previous reports where T rubrum and T mentagrophytes complex were the main causative agents of dermatophytosis. However, the increased incidence of N gypsea complex over M canis is worth highlighting.

Updating the Taxonomy of Dermatophytes of the BCCM/IHEM Collection According to the New Standard: A Phylogenetic Approach.

Recent taxonomical revisions based on multilocus gene sequencing have provided some clarifications to dermatophyte (Arthrodermataceae) family tree. These changes promoted us to investigate the impact of the changed nomenclature of the dermatophyte strains in the BCCM/IHEM fungal collection, which contains strains of all dermatophyte genera except for Ctenomyces. For 688 strains from this collection, both internal transcribed spacer region (ITS) and partial ß-tubulin (BT) sequences were aligned and a multilocus phylogenetic tree was constructed. The ITS + BT phylogentic tree was able to distinguish the genera Arthroderma, Lophophyton, Microsporum, Paraphyton, Nannizzia and Trichophyton with high certainty. Epidermophyton, which is widely considered as a well-defined genus with E. floccosum as the only representative, fell within the Nannizzia clade, whereas the phylogenetic analysis, based on the ITS region alone, differentiates Epidermophyton from Nannizzia as a separate genus. Re-identification and reclassification of many strains in the collection have had a profound impact on the composition of the BCCM/IHEM dermatophyte collection. The biggest change is the decline of prevalence of Arthroderma strains; starting with 103 strains, only 22 strains remain in the genus after reassessment. Most Arthroderma strains were reclassified into Trichophyton, with A. benhamiae and A. vanbreuseghemii leaving the genus. The amount of Microsporum strains also dropped significantly with most of these strains being reclassified into the genera Paraphyton and Nannizzia.

Molecular and Phenotypic Characterization of Nannizzia (Arthrodermataceae).

Phylogenetic studies of the family Arthrodermataceae have revealed seven monophyletic dermatophyte clades representing the genera Trichophyton, Epidermophyton, Nannizzia, Lophophyton, Paraphyton, Microsporum, and Arthroderma. Members of the genus Nannizzia are geo- or zoophiles that occasionally infect humans. With the newly proposed taxonomy, the genus Nannizzia comprises thirteen species, i.e., Nannizzia aenigmatica, N. corniculata, N. duboisii, N. fulva, N. graeserae, N. gypsea, N. nana, N. incurvata, N. perplicata, N. persicolor, N. praecox, and two novel species. Nannizzia polymorpha sp. nov. was isolated from a skin lesion of a patient from French Guiana. For the strain originally described as Microsporum racemosum by Borelli in 1965, we proposed Nannizzia lorica nom. nov. The species are fully characterized with five sequenced loci (ITS, LSU, TUB2, RP 60S L1 and TEF3), combined with morphology of the asexual form and physiological features. A key to the species based on phenotypic and physiological characters is provided.

Epidermophyton floccosum: nucleotide sequence analysis and antifungal susceptibility testing of 40 clinical isolates.

Purpose. Epidermophyton floccosum is an anthropophilic dermatophyte species, which is one of the common causative agents of dermatophytosis in different parts of the world. The aim of the present investigation was to evaluate the genetic diversity of E. floccosum strains isolated from different parts of Iran and to define the in vitro susceptibility profiles of seven antifungal drugs against these clinical isolates.Methodology. Forty clinical strains of E. floccosum isolated from 40 patients with dermatophytosis were subjected to DNA extraction and PCR amplification of the ITS rDNA region using universal primers ITS1 and ITS4. The in vitro activities of griseofulvin, itraconazole, voriconazole, posaconazole, caspofungin, ketoconazole and terbinafine were determined using a broth microdilution method according to the CLSI-M-38A2 protocol.Results. A mean genetic similarity of 99.5 % was found between E. floccosum strains, with intraspecies differences ranging from 0 to 3 nt. The geometric mean (GM) MICs and minimum effective concentrations (MECs) across all isolates were, in increasing order, as follows: terbinafine (GM=0.018 mg l-1), posaconazole (GM=0.022 mg l-1), itraconazole (GM=0.034 mg l-1) and voriconazole (GM=0.045 mg l-1), which had low MICs against all tested strains, whereas caspofungin (GM=0.22 mg l-1), ketoconazole (GM=0.41 mg l-1) and griseofulvin (GM=0.62 mg l-1) demonstrated higher MICs.Conclusion. Our study showed low intraspecies variation within strains of E. floccosum. Furthermore, terbinafine, posaconazole, itraconazole and voriconazole were shown to be the most potent antifungal drugs against E. floccosum strains.

Genus-level identification of dermatophytes by MALDI-TOF MS after 2 days of colony growth.

Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) is becoming a popular technology in clinical microbiology. It is a fast and highly specific method for the routine identification of micro-organisms. In this study, we evaluated the suitability of dermatophyte identification after only 2 days of colony growth using MALDI-TOF MS. Two protein extraction protocols were also evaluated consisting of either formic acid alone or of ethanol-formic acid-acetonitrile to achieve a complete protein extraction. Morphology-based techniques were used as the diagnostic standard methods and MALDI-TOF MS results were obtained using the manufacturer's spectral library. Using the formic acid protein extraction protocol after 2 days of colony growth, 70 and 46% of dermatophytes were properly identified at the genus and species-level respectively. The addition of ethanol-formic acid-acetonitrile extraction protocol increased the identification to 90 and 62%. Based on our observations, we propose a two-step workflow for the fast and reliable identification of dermatophytes after only 2 days of colony growth. This flow chart consists of a first direct deposition procedure with the addition of formic acid, followed by a complete protein extraction when dermatophyte identification is not successful. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, a two-step workflow for the identification of clinical dermatophytes using MALDI-TOF analysis and commercially available spectral library was developed. The workflow consists of an initial direct deposition of the sample on the MALDI plate and formic acid protein extraction at 2 days of growth culture; if dermatophyte identification is not successful, a complete protein extraction using ethanol-formic acid-acetonitrile is subsequently performed. Using this workflow, the correct isolate identifications increase up to 90%; of these, 27% are identified at the genus-level, providing sufficient information to start an antifungal treatment. The method here proposed represents a fast and useful approach to differentiate dermatophytes grown in culture.

PRP8 intein in dermatophytes: Evolution and species identification.

Dermatophytes are keratinophilic fungi belonging to the family Arthrodermataceae. Despite having a monophyletic origin, its systematics has always been complex and controversial. Sequencing of nuclear ribosomal ITS and D1/D2 rDNA has been proposed as an efficient tool for identifying species in this group of fungi, while multilocus analyses have been used for phylogenetic species recognition. However, the search for new markers, with sequence and size variation, which enable species identification in only one polymerase chain reaction (PCR) step, is very attractive. Inteins seems to fulfill these characteristics. They are self-splicing genetic elements present within housekeeping coding genes, such as PRP8, that codify the most important protein of the spliceosome. The PRP8 intein has been described for Microsporum canis in databases but has not been studied in dermatophytes in any other published work. Thus, our aim was to determine the potential of this intervening element for establishing phylogenetic relationships among dermatophytes and for identifying species. It was found that all studied species have a full-length PRP8 intein with a Homing Endonuclease belonging to the family LAGLIDADG. Phylogenetic analyses were consistent with other previous phylogenies, confirming Epidermophyton floccosum in the same clade of the Arthroderma gypseum complex, Microsporum audouinii close to M. canis, differentiating A. gypseum from Arthroderma incurvatum, and in addition, better defining the Trichophyton interdigitale and Trichophyton rubrum species grouping. Length polymorphism in the HE region enables identification of the most relevant Microsporum species by a simple PCR-electrophoresis assay. Intein PRP8 within dermatophytes is a powerful additional tool for identifying and systematizing dermatophytes.

Toward a Novel Multilocus Phylogenetic Taxonomy for the Dermatophytes.

Type and reference strains of members of the onygenalean family Arthrodermataceae have been sequenced for rDNA ITS and partial LSU, the ribosomal 60S protein, and fragments of ß-tubulin and translation elongation factor 3. The resulting phylogenetic trees showed a large degree of correspondence, and topologies matched those of earlier published phylogenies demonstrating that the phylogenetic representation of dermatophytes and dermatophyte-like fungi has reached an acceptable level of stability. All trees showed Trichophyton to be polyphyletic. In the present paper, Trichophyton is restricted to mainly the derived clade, resulting in classification of nearly all anthropophilic dermatophytes in Trichophyton and Epidermophyton, along with some zoophilic species that regularly infect humans. Microsporum is restricted to some species around M. canis, while the geophilic species and zoophilic species that are more remote from the human sphere are divided over Arthroderma, Lophophyton and Nannizzia. A new genus Guarromyces is proposed for Keratinomyces ceretanicus. Thirteen new combinations are proposed; in an overview of all described species it is noted that the largest number of novelties was introduced during the decades 1920-1940, when morphological characters were used in addition to clinical features. Species are neo- or epi-typified where necessary, which was the case in Arthroderma curreyi, Epidermophyton floccosum, Lophophyton gallinae, Trichophyton equinum, T. mentagrophytes, T. quinckeanum, T. schoenleinii, T. soudanense, and T. verrucosum. In the newly proposed taxonomy, Trichophyton contains 16 species, Epidermophyton one species, Nannizzia 9 species, Microsporum 3 species, Lophophyton 1 species, Arthroderma 21 species and Ctenomyces 1 species, but more detailed studies remain needed to establish species borderlines. Each species now has a single valid name. Two new genera are introduced: Guarromyces and Paraphyton. The number of genera has increased, but species that are relevant to routine diagnostics now belong to smaller groups, which enhances their identification.

Molecular epidemiology, phylogeny and evolution of dermatophytes.

Dermatophytes are fungi that invade and propagate in the keratinized skin of mammals, including humans, often causing contagious infections. The species of medical concern belong to the genera Microsporum, Trichophyton, Epidermophyton (in their anamorphic state) and Arthroderma (in their telomorphic state), which were traditionally identified based on their morphology and biochemical characters. Nonetheless, limitations linked to the differentiation of closely related agents at species and strains level have been recently overcome by molecular studies. Indeed, an accurate identification of dermatophytes is pivotal for the establishment of effective control and prevention programs as well as for determining the most appropriate and effective antifungal therapies to be applied. This article reviews the DNA techniques and the molecular markers used to identify and to characterize dermatophyte species, as well as aspects of their phylogeny and evolution. The applications of typing molecular strain to both basic and applied research (e.g., taxonomy, ecology, typing of infection, antifungal susceptibility) have also been discussed.

[Influence of the ecological group on the in vitro antifungal susceptibility of dermatophytic fungi]. / Influencia del grupo ecológico sobre la sensibilidad in vitro de los hongos dermatofitos a los antifúngicos.

BACKGROUND: Dermatophytes can be divided into geophilic (soil), zoophilic (animals) and anthropophilic (humans) strains, depending on the source of the keratin that they use for nutritional purposes. AIMS: The in vitro susceptibility of clinical isolates of dermatophyte fungi has been studied in the 3 ecological groups with several antifungal agents for the topical management of dermatophytoses in order to determine their relationship with the ecological group. METHODS: A standardised dilution micromethod in a liquid medium was used for the determination of the in vitro antifungal activity of 9 topical antifungal drugs: amorolfine (AMR), bifonazole (BFZ), clotrimazole, econazole, ketoconazole, miconazole, oxiconazole, terbinafine (TRB) and tioconazole. The in vitro activity was obtained against 124 clinical isolates of dermatophyte moulds from the anthropophilic, zoophilic and geophilic ecological groups. RESULTS: The in vitro antifungal activity was different depending on the ecological group, although a species-dependent profile was also observed. CONCLUSIONS: Azole derivatives showed a similar antifungal profile, being more active against anthropophilic dermatophytes > zoophilic > geophilic. Activity of TRB and AMR was different from that of azole derivatives (zoophilic > anthropophilic > geophilic). A higher in vitro antifungal activity against the 3 ecological groups was observed with TRB and AMR, whilst BFZ was the less active drug.

Molecular epidemiology of dermatophytosis in Tehran, Iran, a clinical and microbial survey.

In the framework of a survey on dermatophytoses, 14,619 clinical specimens taken from outpatients with symptoms suggestive of tinea and referred to a Medical Mycology laboratory in Tehran, Iran, were analyzed by direct microscopy and culture. In total, 777 dermatophyte strains recovered in culture were randomly identified by a formerly established RFLP analysis method based on the rDNA ITS regions. For confirmation of species identification, 160 isolates representing the likely entire species spectrum were subjected to ITS-sequencing. Infection was confirmed in 5,175 collected samples (35.4%) by direct microscopy and/or culture. Tinea pedis was the most prevalent type of infection (43.4%), followed by tinea unguium (21.3%), tinea cruris (20.7%), tinea corporis (9.4%), tinea manuum (4.2%), tinea capitis (0.8%) and tinea faciei (0.2%). Trichophyton interdigitale was the most common isolate (40.5%) followed by T. rubrum (34.75%), Epidermophyton floccosum (15.6%), Microsporum canis (3.9%), T. tonsurans (3.5 %) and M. gypseum (0.5%). Other species included M. ferrugineum, T. erinacei, T. violaceum, T. schoenleinii, and a very rare species T. eriotrephon (each one 0.25%). The two strains of T. eriotrephon isolated from tinea manuum and tinea faciei are the second and third reported cases worldwide. Application of DNA-based methods is an important aid in monitoring trends in dermatophytosis in the community.

Molecular typing of Epidermophyton floccosum isolated from patients with dermatophytosis by RAPD-PCR.

We evaluated the ability of randomly amplified polymorphic DNA (RAPD) to type Epidermophyton floccosum isolates recovered from patients with dermatophytosis originating from different regions of Iran. A total of 13 clinical isolates of E. floccosum obtained from Iranian patients were analyzed by RAPD with 7 arbitrary primers (OPN16, OPD18' OPU15, OPX19, R28, OPA04 and OPAA17). Among the applied primers, OPN16 produced banding patterns from all the isolates. In addition, some of the isolates had very close relation. The phenon line which represented the mean similarities was at the value of 73%. At this level, 4 groups were characterized. Two isolates of a patient had different molecular patterns, suggesting infection transmission from different sources in the case of a single patient. RAPD-PCR provided a rapid and practical tool for identification of E. floccosum isolates, which was independent of morphological characteristics, and enhanced laboratory diagnosis of dermatophytosis.

Recent dermatophyte divergence revealed by comparative and phylogenetic analysis of mitochondrial genomes.

BACKGROUND: Dermatophytes are fungi that cause superficial infections of the skin, hair, and nails. They are the most common agents of fungal infections worldwide. Dermatophytic fungi constitute three genera, Trichophyton, Epidermophyton, and Microsporum, and the evolutionary relationships between these genera are epidemiologically important. Mitochondria are considered to be of monophyletic origin and mitochondrial sequences offer many advantages for phylogenetic studies. However, only one complete dermatophyte mitochondrial genome (E. floccosum) has previously been determined. RESULTS: The complete mitochondrial DNA sequences of five dermatophyte species, T. rubrum (26,985 bp), T. mentagrophytes (24,297 bp), T. ajelloi (28,530 bp), M. canis (23,943 bp) and M. nanum (24,105 bp) were determined. These were compared to the E. floccosum sequence. Mitochondrial genomes of all 6 species were found to harbor the same set of genes arranged identical order indicating that these dermatophytes are closely related. Genome size differences were largely due to variable lengths of non-coding intergenic regions and the presence/absence of introns. Phylogenetic analyses based on complete mitochondrial genomes reveals that the divergence of the dermatophyte clade was later than of other groups of pathogenic fungi. CONCLUSION: This is the first systematic comparative genomic study on dermatophytes, a highly conserved and recently-diverged lineage of ascomycota fungi. The data reported here provide a basis for further exploration of interrelationships between dermatophytes and will contribute to the study of mitochondrial evolution in higher fungi.

Single-step PCR using (GACA)4 primer: utility for rapid identification of dermatophyte species and strains.

Dermatophytes are fungi that belong to three genera: Epidermophyton, Microsporum, and Trichophyton. Identification of dermatophyte species is essential for appropriate diagnosis and treatment of dermatophytosis. Routine identification depends on macroscopic and microscopic morphology, which is time-consuming and does not identify dermatophyte strains. In this study, two PCR-based methods were compared for their abilities to identify 21 dermatophyte isolates obtained from Egyptian patients to the species and strain levels. The first method employed a two-step method: PCR amplification, using ITS1 and ITS4 as primers, followed by restriction enzyme digestion using the endonuclease MvaI. The second method employed a one-step approach employing the repetitive oligonucleotide (GACA)(4) as a primer. Dermatophyte strains were also identified using a conventional culture method. Our results showed that the conventional culture method identified four species: Microsporum canis, Trichophyton mentagrophytes, Trichophyton rubrum, and Trichophyton violaceum. Moreover, both PCR methods agreed with the diagnosis made using the conventional approach. Furthermore, ITS1/ITS4-based PCR provided no strain differentiation, while (GACA)(4)-based PCR identified different varieties among the T. mentagrophytes isolates. Taken together, our results suggest that (GACA)(4)-based PCR has utility as a simple and rapid method for identification of dermatophyte species as well as utility for differentiation of T. mentagrophytes variants.

[Investigation of the agents and risk factors of dermatophytosis: a hospital-based study]. / Dermatofitozlarda etkenlerin ve risk faktörlerinin arastirilmasi: hastane bazli bir Calisma.

The aims of this study were the detection of distribution of dermatophyte species isolated from the clinical samples of patients with dermatophytosis and the evaluation of risk factors for the development of dermatophytosis. A total of 441 skin, nail and scalp/hair specimens obtained from 301 patients (151 were male; age range 2 months-80 years, median 42 years) and 884 foot and hand skin and nail specimens obtained from 221 control subjects (110 were male; age range 5-75 years, median 36 years) were included to the study between the period of January to December 2005. All the samples have been evaluated by direct microscopic (DM) examination and by culture. A total of 121 (40.2%) patients yielded positivity for dermatophytes, of them 63 were positive by both DM and culture methods, seven were only culture positive, and 51 were only DM positive. Nine (9.8%) of 92 culture positive samples from 70 patients were found negative in DM, while 85 (50.6%) of 168 DM positive samples from 114 patients were negative in culture. 23.5% (12/51) of DM positive but culture negative patients were given antifungal therapy previously. The most prominent species isolated from the cultures were Trichophyton rubrum with a rate of 68.4% (63/92), followed by T. mentagrophytes (18.4%); T. violaceum (3.3%); T. verrucosum, T. tonsurans and Epidermophyton floccosum (2.2% for each); T. schoenleini, Microsporum canis and Trichophyton sp. (1.1% for each). Of the patient samples whose cultures were positive, 45% were from the foot skin. The presence rate of dermatophytes in controls was found as 3.2% (7/221); T. rubrum was isolated from the foot skin of five and T. mentagrophytes was isolated in toenail of two control subjects. About 42% of the samples belonged to the patients who admitted to hospital between December to February period. The evaluation of the risk factors revealed that presence of trauma, pet contact, ritual cleansing and diabetes mellitus had no effect on the development of dermatophytoses, however the presence of fungal infection in the family, male gender, some professions (being farmer, worker and retired), and the use of immunosupressive drugs have been found to increase the risk of dermatophytosis. The number of cases with dermatophytoses started to increase beginning from the age of 20 and peaked in the ages between 40-59 years old. As a result T. rubrum was determined as the most frequently isolated dermatophyte and tinea pedis was the most frequently observed clinical form in our hospital, emphasizing the importance of early diagnosis and effective treatment in superficial fungal infections which have high morbidity.

Dermatophytoses in outpatients attending the Dermatology Center of Avicenna Hospital in Qazvin, Iran.

Dermatophytosis is still being considered as one of the major public health problems in many parts of the world. To identify the prevalence and etiological agents of dermatophytoses, a study was carried out between 2004 and 2006. Out of 1023 subjects suspected to have cutaneous mycoses, 348 (34%) patients were affected with dermatophytoses. The causative agents were identified macroscopically and microscopically after the clinical samples were subjected to potassium hydroxide examination and culture isolation. Epidermophyton floccosum was the most frequently isolated species representing 32.8% of isolates, followed by T. rubrum (18.1%), T. verrucosum (17.2%), T. mentagrophytes var. interdigitale (15.8%), T. mentagrophytes var. mentagrophytes (6.6%) and T. violaceum, T. schoenleinii and Microsporum canis (0.9%). The most common type of infection was tinea cruris (31.9%) affecting in particular male patients. Some other most prevalent tinea types were tinea corporis (20.7%), tinea pedis (19%), and tinea unguium (11.2%). To the best of our knowledge, this is the first report on dermatophytoses in Qazvin and the first study that shows tinea cruris as a major type of superficial fungal infection in Iran. The frequency of tinea was higher in males and tinea cruris showed a remarkably increasing tendency and was an important public health issue in Qazvin.

Analysis of the dermatophyte species isolated in the British Isles between 1980 and 2005 and review of worldwide dermatophyte trends over the last three decades.

Infections of the skin, hair and nails by dermatophyte fungi are common in developed and developing countries alike. However, the species involved and the resulting clinical entities vary both geographically and with time. We have surveyed 15,333 dermatophytes obtained from primary isolations at the Mycology Reference Laboratory, Bristol, UK from 1980 through 2005. Several striking trends in dermatophyte prevalence were apparent over this period. The relative frequencies of isolations of Microsporum canis (cat and dog ringworm), Trichophyton verrucosum (cattle ringworm), T. mentagrophytes var. mentagrophytes (rodent ringworm) and Epidermophyton floccosum (a cause of human groin and foot infections) all decreased by 90%. Conversely, the contributions of T. tonsurans and T. violaceum (two anthropophilic scalp-infecting species) to total dermatophyte isolations increased by 1000% over the same period. Finally, T. rubrum and T. mentagrophytes var. interdigitale, the two common causes of foot infection comprised 80% of all dermatophytes isolated in 1980 and 90% of isolations in 2005. Similar trends in dermatophyte prevalence were evidenced throughout the British Isles, based on the voluntary reporting of isolations from a large number of British laboratories at 5-yearly intervals over the same period. The implications of these changing patterns of dermatophyte species, and the clinical entities they produce are discussed in the context of a review of worldwide dermatophyte isolations over the last three decades, with emphasis on the causal agents of tinea capitis.

Species distribution and antifungal susceptibilities of dermatophytes during a one year period at a university hospital in Turkey.

Dermatophyte infections have been considered to be a major public health problem in many parts of the world. The aim of this study was to determine the causative agents of dermatophytoses and their antifungal susceptibilities in a Turkish University Hospital, west of Turkey. A total of 926 patients suspected to have dermatophytic lesions were examined over a period of 1 year (2001-2002). Samples collected from skin, hair and nails were submitted to direct microscopical examination using KOH and Calcofluor white stain, cultured on Sabouraud dextrose agar and Mycosel agar. The prevalence of dermatophytoses was 7.34% (68/926). Trichophyton rubrum was the most frequent dermatophyte isolated (56%) followed by T. mentagrophytes (38%), T. violaceum (1.5%), T. verrucosum (1.5%), Microsporum canis (1.5%) and Epidermophyton floccosum (1.5%). Tinea pedis (47%) was the most common type of infection, followed by tinea unguium (29%), tinea inguinalis (15%), tinea corporis (7.4%) and tinea capitis (1.6%). Secondary, we have tested 68 strains of dermatophytes against four antifungal agents following mainly the National Committee for Clinical Laboratory Standards M38-P standard for filamentous fungi. In general, all antifungals were shown to be highly effective and itraconazole and naftifine appeared more active than ketoconazole and oxiconazole.

The complete DNA sequence of the mitochondrial genome of the dermatophyte fungus Epidermophyton floccosum.

We report here the complete nucleotide sequence of the 30.9-kb mitochondrial genome of the dermatophyte fungus Epidermophyton floccosum. All genes are encoded on the same DNA strand and include seven subunits of the reduced nicotinamide adenine dinucleotide ubiquinone oxireductase (nad1, nad2, nad3, nad4, nad4L, nad5, and nad6), three subunits of cytochrome oxidase (cox1, cox2, and cox3), apocytochrome b (cob), three subunits of ATP synthase (atp6, atp8, and atp9), the small and large ribosomal RNAs (rns and rnl), and 25 tRNAs. A ribosomal protein gene (rps5) is present as an intronic ORF in the large ribosomal subunit. The genes coding for cob and cox1 carry one intron and nad5 carries two introns with ORFs. The mtDNA of E. floccosum has the same gene order as Trichophyton rubrum mtDNA, with the exception of some tRNA genes. Maximum likelihood phylogenetic analysis confirms T. rubrum as a close relative of E. floccosum. This is the first complete mitochondrial sequence of a species of the order Onygenales. This sequence is available under GenBank accession number AY916130.

Tinea cruris in female prostitutes.

Tinea cruris is a dermatophytosis that mainly affects males. Infections in females are rare, and there are no known data on the frequency of tinea cruris in female prostitutes. We describe seven female prostitutes with tinea cruris with on age range of between 19-34 years (mean 25.3). Each prostitute had a mean of 50 sexual partners per month. Four Trichophyton mentagrophytes (57.1%), 2 T rubrum (28.6%), and 1 Epidermophyton floccosum (14.3%) isolates were cultered. Tinea cruris transmission is mainly indirect, but direct contact may serve to transmit the disease in some cases, and the spread of active lesions in prostitutes through multiple contacts among with their clients is possible.

Application of PCR to distinguish common species of dermatophytes.

This report describes the application of PCR fingerprinting for the identification of species and varieties of common dermatophytes and related fungi utilizing as a single primer the simple repetitive oligonucleotide (GACA)(4). The primer was able to amplify all the strains, producing species-specific profiles for Microsporum canis, Microsporum gypseum, Trichophyton rubrum, Trichophyton ajelloi, and Epidermophyton floccosum. Intraspecific variability was not observed for these species. Instead, three different profiles were observed in the Trichophyton mentagrophytes group.