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Dermatophytoses are inflammatory cutaneous mycoses caused by dermatophyte fungi of the genera Trichophyton, Microsporum, and Epidermophyton that affect both immunocompetent and immunocompromised individuals. With therapeutic failure, dermatophytoses can become chronic and recurrent. This is partly due to their ability to develop biofilms, microbial communities involved in a polymeric matrix attached to biotic or abiotic surfaces, contributing to fungal resistance. This review presents evidence accumulated in recent years on antidermatophyte biofilm activity. The following databases were used: Web of Science, Medline/PubMed (via the National Library of Medicine), Embase, and Scopus. Original articles published between 2011 and 2020, emphasizing the antifungal activity of conventional and new drugs against dermatophyte biofilms were eligible. A total of 11 articles met the inclusion criteria and were reviewed – the studies used in vitro and ex vivo (fragments of nails and hair) experimental models. The articles focused on reports of antibiofilm activity for conventional antifungals, natural drugs, and new therapeutic tools. The strains reported on were T. mentagrophytes, T. rubrum, T. tonsurans, M. canis, and M. gypseum. Between the studies, the wide variability of experimental conditions in vitro and ex vivo was observed. The data suggest the need for methodological standardization (at some minimum). This review systematically presents current studies involving agents that present antibiofilm activity against dermatophytes; and an overview of the ideal in vitro and ex vivo experimental conditions to guarantee biofilm formation that may assist future research. Lay abstract This review presents the current studies on the antibiofilm activities of drugs against dermatophytes and ideal experimental conditions, which might guarantee in vitro and ex vivo biofilm formation. It can be useful to examine the efficacy of new antimicrobial drugs against dermatophytes.

Made available in DSpace on 2018-11-26T16:05:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-08-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) 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 Glade 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. Univ Estadual Sao Paulo, Inst Biociencias, Dept Microbiol & Imunol, Sao Paulo, Brazil Univ Fed Rio Grande do Norte, Inst Med Trop RN, Natal, RN, Brazil CAPES: 12481-13-0 CNPq: 306590/2015-8

International audience; In this critical literature review, we summarize the epidemiological trends of dermatophytoses reported in Africa. Our findings clearly emphasize the heavy burden of dermatophytosis in Africa. Tinea capitis is the primary clinical presentation of dermatophytosis in African children throughout the entire African continent. The disease affects more than 20% of school-age children in West Africa, while the prevalence ranges from 10% to more than 70% in other regions of Africa. In African adults, the presence of tinea corporis is the most frequent indicator of dermatophytosis. However, epidemiological studies have been primarily conducted on particular patient groups that are not representative of the general population. We examined dermatophyte species distribution patterns. We observed a predominance of anthropophilic dermatophytes, mainly T. violaceum, in the North and East of Africa and both T. soudanense and M. audouinii in the Western and Central regions of the continent. Interestingly, the zoophilic species, M. canis, has recently emerged in North and East Africa. Optimization of both mycology diagnosis capacities and epidemiological methodology would provide insight into the role that climate and other global aspects of the human environment play in dermatophyte epidemiology. We advocate that using a multisectoral and collaborative strategy would strengthen such future studies.

Dermatophytosis is currently a disease of global importance and a public health burden. It is caused by dermatophytes, which attack and grow on dead animal keratin. Dermatophytes belong to three genera, namely, Epidermophyton, Microsporum, and Trichophyton. The predominant clinical forms and causative agents vary from one region of the world to another. Poor socioeconomic status, high population densities, and poor sanitary conditions are some of the factors responsible for the high prevalence of dermatophytosis in many developing countries, which include countries in southern and eastern Africa, the focus of this review. To the best of our knowledge, there is currently no review article on published findings on dermatophytosis in the eastern and southern parts of Africa. This information will be of interest to the medical and research community since the world has become a global village. This review covers published research findings in eastern and southern regions of Africa until this date. The countries covered in the current review include Kenya, Ethiopia, Tanzania, South Africa, Mozambique, Madagascar, Malawi, Rwanda, Burundi, Uganda, Zambia, Zimbabwe, and Botswana. T. violaceum is the most common human etiological agent in all the countries under review with prevalence ranging from 56.7% to 95%, except for Madagascar (M. langeronii, reclassified as M. audouinii), Uganda (M. gypseum) and Malawi (M. audouinii). Tinea capitis was the most clinical type, followed by tinea corporis. Etiological agents of animal dermatophytoses were variable in the countries where they were reported. Major risk factors for dermatophytoses are age, climatic, and socioeconomic factors.

Tinea refers to superficial infection with one of three fungal genera—Microsporum, Epidermophyton, or Trichophyton—that are collectively known as dermatophytes. These infections are among the most common diseases worldwide and cause chronic morbidity. They are usually diagnosed by direct microscopy and fungal culture, which are burdensome to perform in the clinical setting. To supplement conventional methods, we developed a new method that employs an immunochromatography test for detection of dermatophyte infections. First, anti-Trichophyton monoclonal antibodies (mAb) were produced in mice using a Trichophyton allergen solution as an immunogen. The mAb specificity was assessed by immunostaining alcohol fixed slide cultures and formalin fixed paraffin-embedded microbial samples. Both alcohol- and formalin-fixed samples of all seven species of Trichophyton tested displayed positive immunostaining. Immunochromatography test strips were created using the anti-Trichophyton mAb. The efficiency of the test strip was assessed in patients diagnosed with tinea unguium and in healthy volunteers. Of the 20 patient nails tested, 19 tested positive and one tested negative, whereas of the 17 volunteer nails, only one tested positive. However, KOH microscopic examination of the volunteer nail that tested positive revealed the existence of Trichophyton hyphae. Although the number of nails assayed was small, since the assay had a sensitivity of 95.0% (19/20) and a specificity of 94.1% (16/17), the obtained results were considered to be promising. Thus, while further investigation with a greater number of samples is necessary, this method could potentially be employed as a new diagnostic tool for Trichophyton in the future.

Treatment of dermatophytoses with currently available antimycotic agents is often tedious and sometimes unsatisfactory. A search for better therapeutic methods-ideally with an immediate fungicidal effect-has, among others, lead to photodynamic procedures as a promising alternative, and recently curcumin was found to be a suitable agent for this application. In this study the effect of photodynamic treatment with curcumin on dermatophytes was tested in vitro. Wells of microtiter plates were filled with conidia of Trichophyton rubrum, Trichophyton interdigitale, Trichophyton terrestre, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum in buffer. Then curcumin was added to the conidia and after 20 min the assays were irradiated one time only with visible light (peak wave length 367 nm, 5 J/cm2). Thereafter the wells were filled up with Sabouraud's glucose broth and in the following fungal growth was measured photometrically. The results showed that all dermatophytes were markedly inhibited depending on the concentration of curcumin. With 5.4 mg/l curcumin plus irradiation fungal growth was significantly suppressed over a period of 96 h (P < .001). Even after 96 h inhibition of T. rubrum was still complete and marked for all other species as well. M. gypseum was least susceptible. Our results are very encouraging to pursue the development of a photodynamic therapy of tinea with curcumin. The outstanding tolerance of curcumin and the innocuousness of the required light are favorable preconditions for this task.

We analysed 15,101 biological samples from patients presenting with superficial mycoses who attended outpatient services over a 10-year period. Scale samples were processed for direct microscopic examination with 15% KOH and cultured on Sabouraud glucose agar plus chloramphenicol and cycloheximide. Laboratory examination confirmed 4,709 cases of superficial mycosis (31.18%), of which 2,084 (44.26%) were dermatophytoses. The species most frequently encountered was Trichophyton rubrum (71.2%), followed by T. tonsurans (6.9%), T. mentagrophytes (5.5%), Microsporum canis (4.5%) and Epidermophyton floccosum (1.3%). The most frequent clinical form of dermatophytosis was tinea unguium (59.9%), followed by tinea pedis (24.5%). We demonstrate that the number of cases of T. rubrum is increasing in Mexico.

The introduction of systemic antifungal drugs which act upon different targets is the main issue of the in vivo antifungal resistance control. Different factors, such as growth curve phase, quality of the specimen, quantity of the inoculum, temperature, pH, culture medium composition, incubation duration and solvent, are believed important factors affecting minimum inhibitory concentration (MIC) value to most of the antifungal agents. We assayed an in vitro susceptibility test with 40 isolates of dermatophytes: Microsporum canis, Trichophyton rubrum, Trichophyton mentagrophytes and Epidermophyton floccosum against griseofulvin, fluconazole, itraconazole and terbinafine, using the guidelines of the M38-P document approved by the NCCLS. We determined the growth curves, to estimate the specific growth rate (mu max) and the generation time (G) of each dermatophyte, using dry weight and spectrophotometry methods. We demonstrate that, at 192 h, all fungi tested had a constant growth curve and we considered this as the optimal time for MIC determination. Terbinafine, griseofulvin and itraconazole possessed the highest antifungal activity against the four groups of dermatophytes studied. Fluconazole demonstrated no efficacy. Our MIC results differ from other authors and this difference is due to the timing of the MIC determination based on the growth curve of each fungi tested.

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.

Previous studies have described some antibacterial effects of antimicrobial peptides (AMPs) expressed in human skin, but little is known about their possible activity against dermatophytes. Therefore we have tested the effects of human β-defensin 2 (hBD-2), ribonuclease 7 (RNase 7) and psoriasin on the in vitro growth of four dermatophyte species. Germinating conidia of Trichophyton rubrum, T. mentagrophytes, Microsporum canis and Epidermophyton floccosum were exposed in vitro to hBD-2, RNase 7, psoriasin and fluconazole. Subsequent fungal growth was measured photometrically over 168 hours. All AMPs significantly inhibited fungal growth, with the degree of inhibition dependent on the dermatophyte species and the specific AMP. E. floccosum was found to be the most susceptible species in that it was markedly suppressed by all AMPs, whereas M. canis was inhibited only by psoriasin. Overall, psoriasin was the most effective AMP and had even stronger inhibitory effects on some dermatophytes than fluconazole. Our findings show that AMPs expressed in human skin can, in principal, inhibit the growth of dermatophytes in vitro. Therefore the question whether AMPs are relevant for human protection against tineas is justified and should be addressed by investigating their role in vivo.

Dermatophytic infections are common worldwide but the distribution of dermatophyte species varies among geographical areas and changes over time. The aim of this study was to determine the epidemiologic profile of dermatophytosis in Stockholm, Sweden. Laboratory records comprising direct microscopy and culture results of 37,503 specimens from skin, hair and nail scrapings collected from January 2005 through December 2009 were retrospectively analyzed in the mycology laboratory at Karolinska University Hospital. Onychomycosis had, over time, the highest overall prevalence of 14.1%, followed by tinea pedis (4.4%). Trichophyton rubrum was the predominant pathogen isolated from these cases (83.2%), followed by T. mentagrophytes (7.4 %). In contrast, T. violaceum and T. soudanense accounted for 81.6% of the isolates from patients with tinea capitis.

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.

The use of the agar diffusion Neo-Sensitabs method to determine antifungal susceptibility of 59 isolates of dermatophytes, namely Epidermophyton floccosum, Microsporum canis, M. gypseum, Trichophyton mentagrophytes, T. rubrum and T. tonsurans to Clotrimazole (CLZ), Itraconazole (ITZ) and Terbinafine (TBF) is described. Results obtained are compared to the minimum inhibitory concentrations (MIC) determined by an adaptation of the NCCLS-M38-A procedure. Using the diffusion method, all strains showed a broad zone of inhibition at the first available reading time (3 or 7 days). Using the broth microdilution method, the geometric mean MIC (microg/ml) with regard to all isolates was < or = 0.03 for TBF, < or = 0.069 for CLZ and < or = 0.919 for ITZ. In both methods, TBF was the most active antifungal agent against all isolates tested. The two methods evaluated were able to detect the resistance of the quality control strains of Aspergillus fumigatus to ITZ. Even though a reference method for testing dermatophytes still has not been developed, our data suggest that the Neo-Sensitabs diffusion method could provide a simple procedure for the antifungal susceptibility testing of dermatophytes in the routine clinical laboratory.

Duration of therapy is an important factor determining patients' compliance in dermatomycosis clinical practice. We undertook a prospective, randomised, double-blind, parallel group study to investigate the efficacy and tolerability of once daily treatment with terbinafine 1% cream for 1 week, compared to its vehicle, in adult patients with interdigital tinea pedis. Efficacy was assessed in terms of mycological cure, total clinical signs and symptoms scores, and clinical response, 1 day and 1, 5 and 7 weeks after end of treatment. Terbinafine 1% cream was significantly more effective than its vehicle in achieving and maintaining mycological cure for 7 weeks: 91.4% vs. 37.1%, P0.001. Terbinafine was also significantly more effective than its vehicle in reducing total clinical signs and symptoms scores, and in achieving clinical response. We conclude that terbinafine 1% cream, applied once daily for 7 days, is an effective and well-tolerated treatment for interdigital tinea pedis in nonimmunocompromised patients. The short duration of treatment needed to achieve mycological cure has important implications for patient compliance and for control of infection within the community.

During a period of 1 year, out of 202 clinically suspected cases of tinea unguium, 53 (26%) were confirmed by mycological cultures for dermatophytes. Trichophyton rubrum was the most common fungus isolated in 46 (87%) patients, followed by T. violaceum in four (7%), T. interdigitale in two (4%) and Epidermophyton floccosum in one (2%). The disease was more common in adult males and fingernails were found to be affected more often than toenails. The distal and lateral variety was seen in 41 (77%) patients, total secondary dystrophic type in 11 (21%) and proximal subungual type in one (2%). Clinical diagnosis alone is not reliable and mycological confirmation is mandatory for this potentially curable disease.

Dermatophyte species are common keratinophilic fungi responsible for superficial infections called dermatophytosis or ringworm and composed of three anamorphic genera, Trichophyton, Microsporum and Epidermophyton. Through the use of several complementary molecular methods, dermatophytes have been shown to constitute an homogeneous group of species with very low genetic diversity contrasting with high phenotypic heterogeneity. For diagnostic applications, distinction among isolates to the species level was easily performed using polymerase chain reaction-based assays, which could be useful tools in the mycology laboratory, particularly for atypical isolates. In contrast, in all but a few cases distinction between dermatophyte strains has failed, which has hindered the development of molecular-based epidemiological investigations.

The taxonomy of the dermatophyte Trichophyton megninii has been the subject of much discussion since it was first isolated by Sabouraud in 1893. Initially he named it Trichophyton a culture rose and later T. rosaceum. It has been confused with the Microsporum (Epidermophyton) gallinae described by Megnin.Nowadays most mycologists consider T. rosaceum to be a synonym of the T. megninii, although some French authors still use Sabouraud's denomination.It is an exclusively anthropophilic dermatophyte with a broad geographic distribution, but in general a low incidence in most countries, except in Portugal, Corsica and Sardinia where it causes infections of both hairy and glabrous skin zones and nails in humans.T. megninii is an uncommon cause of ringworm in Spain and is mainly restricted to Galicia, and even there the incidence is low; it has been isolated only five times in our clinical practice with two more cases described previously in the literature, and predominantly affects females. Case reports show t...

The antifungal activity of a new topical imidazole, bifonazole (BAY h 4502, Bayer AG Institute for Chemotherapy), was compared in vitro with that of clotrimazole (BAY b 5097, Schering Corporation) in tests with 67 pathogenic and commensal yeasts, 45 dermatophytes and 14 miscellaneous pathogenic fungi by an agar dilution method. Three media, Kimmig's agar, Sabouraud's agar, and casein-yeast extract-glucose agar were used. Bifonazole was inhibitory for nearly all the yeasts tested including Candida albicans, C. parapsilosis, and Torulopsis glabrata with geometric mean minimal inhibitory concentrations (G-MIC) averaging 5 micrograms ml-1 on all three media. Clotrimazole was the more active drug against these same species with G-MIC's ranging from 0 . 25 to 2 . 10 micrograms ml-1. Results with bifonazole were affected by choice of medium with Kimmig's agar generally giving the lowest MIC's; results with clotrimazole were also affected by choice of medium but to a lesser degree. In nearly all instances, both bifonazole and clotrimazole were inhibitory for the dermatophytic fungi at concentrations of 0 . 50 micrograms ml-1 or less and clotrimazole was the more active drug. Choice of medium was, in general, not a factor with these latter fungi which included Epidermophyton, Trichophyton, and Microsporum species. Both drugs were active against species of Aspergillus (G-MIC's of 3 . 18 micrograms ml-1), Fusarium (G-MIC's ranging from 1 . 59 to 12 . 70 micrograms ml-1) and Scopulariopsis (G-MIC's of 1 . 78 micrograms ml-1); clotrimazole was the more active drug by factors of 2- to 4-fold on all three media. Bifonazole MICs were shown to vary with pH (maximal activity at pH 6 . 5) with selected yeasts when tested on Kimmig's agar. Differences in results obtained with varying inoculum sizes for these same yeasts generally were unremarkable. With selected species of yeasts and dermatophytes, it was determined that the ratio of minimal fungicidal to inhibitory concentrations (MFC/MIC) was much lower for bifonazole than for clotrimazole.

Antigens were prepared from young mycelial growth of 20 species of dermatophytes, and tested by double diffusion against homologous and heterologous antisera raised in rabbits. 48 distinct antigens were recognised by the procedures used. Although there were a considerable number of common reactions, there were significant differences between species and groups. Species of Microsporum, with the exception of M. gypseum and M. persicolor, form a coherent group distinct from Epidermophyton and Trichophyton. All Trichophyton species investigated with the exception of T. ajelloi, were serologically closely related. M. gypseum, T. ajelloi and M. persicolor showed affinities with both Microsporum and Trichophyton, and possibly form an intermediate group. The system used does not permit differentiation of species by serological means, but gives a new dimension to the inter-relationships of these fungi.

One hundred and forty-seven isolates distributed among 22 species of dermatophytes were tested for ability to assimilate 23 carbon sources and 4 nitrogen sources, and to hydrolyse casein, tyrosine, gelatine, starch and urea. Differences were found among species in the rate of growth on 11 of the carbon sources, 2 of the nitrogen sources and the time taken to hydrolyse urea. Based on these findings, a practical scheme allowing differentiation of the 22 species investigated is presented. Since the differences in assimilation pattern did not correlate with morphological divisions, this scheme may prove useful in situations where conventional morphological techniques fail to provide an adequate identification of an unknown isolate.

The cellular fatty acids (C11-C20) from 18 species and strains within the genera Microsporum, Trichophyton, and Epidermophyton were determined by gas liquid chromatography. In addition, the effects of incubation time and temperature on fatty acid composition were investigated in selected species. The dermatophytes investigated represented anthropophilic, geophilic, and zoophilic species. Linoleic (18:2), oleic (18:1), and palmitic acid (16:0), accounted for 83.6-94.5% of the fatty acids of dermatophytes. Fatty acid composition and degree of unsaturation did not show any correlations with taxonomic status or ecological group. Incubation time influenced fatty acid composition slightly, but tendencies towards unsaturation and chain elongation were not observed. Elevated incubation temperature (37 degrees C) tended to increase the degree of total fatty acid unsaturation.

From 1972 to 1977 the authors examined 1,311 patients in Rome affected by ringworm of the scalp, beard and body, comparing their findings with a study made in Milan between 1969 to 1973 and with earlier Italian studies from 1900 to date. It appears that at the beginning of the century scalp ringworm was usually caused by Trichophyton violaceum and T. tonsurans, whereas Microsporum canis was rarely found. Today the Trichophyton species are rarely isolated, whereas Microsporum species, particularly M. canis (88.9% of the cases in Rome, 74.6% in Milan), predominate in the etiology of scalp ringworm. Ringworm of the beard in Rome is mainly caused by T. mentagrophytes (50% of the cases) and T. verrucosum (25%). In Milan the frequency of T. verrucosum is 51.2% and of T. mentagrophytes 38.5%. Ringworm of the body today is mainly due to M. canis (47.8% of the cases in Rome and 65.7% of those in Milan). These ringworms in Rome and Milan are caused mostly by the zoophilic dermatophytes that have supplanted the anthropophilic dermatophytes, which were the main cause of dermatomycoses in the early years of this century. This change, particularly evident after World War II, appears to result from improved socio-economic and hygienic conditions, with resulting decrease of infections through interhuman contacts, and from increased numbers of pet animals and consequent increase of stray cats and dogs, which result in increase of infections of animal origin.

An epidemiologic study of the dermatophytoses in Salamanca (Spain) from 1973 to 1976 was performed. Dermatophyte species were identified in 224 patients with clinical tinea infections; 31 bovines, 18 rodents and 70 soil samples. The prevalence of Trichophyton verrucosum and Epidermophyton floccosum was strikingly high in relation to other statistics. The most common clinical forms were tinea corporis and tinea cruris. Tinea capitis by anthropophilic species was uncommon.

5100 isolates belonging to 14 spp. of dermatophytes were obtained from 10 011 samples of hair, skin, nail and beard in Portugal over the years 1962–71.The relationship between the species and the site of the disease; the sex, age, occupation of the patients and the origin of the samples was investigated. The biology of the fungi and the epidemiology of the disease were studied. Dermatophytes were found on skin and nails of symptomless individuals and on objects in contact with patients. The fungi were viable for 47 months. Their lipolytic and alkalinisation ability on medium were studied. Cutaneous sensitivity tests, immunofluorescence and immunodiffusion were used to determine host reaction in experimental human infections.

Six hundred and two cases of dermatophytosis were analyzed according to age, anatomical distribution, ethnic group and sex. 91"5% of the children were Negroid whereas 70.3% of the adults were Caucasoids. 92.9% of all cases were caused by the anthropophilic dermatophytes. Microsporum audouinii caused 53. 1% of the infections in children and Trichophyton rubrum was the causative organism in 78.5% of the adult cases.The following statistically significant differences were found in Negroid children: tinea capitis was more frequent in boys than in girls; tinea corporis occurred more frequently in girls than in boys; and M. audouinii and T. tonsurans var. sulfureurm infections were more frequent in boys than in girls.Lymphadenopathy was observed in 57.1% of the Negroid girls and 36.4% of the boys. Kerion formation was equally distributed between girls and boys and occurred in 17% of the scalp infections. Dermatophytids were found in 4.1% of the Negroid children.The following significant differences were found i...

Allergenic glycopeptides have been extracted from cultures of Trichophyton mentagrophytes, T. rubrum, T. schoenleinii, Microsporum canis, Keratinomyces ajelloi and Epidermophyton floccosum. These have very similar chemical structures and all give rise to both immediate and delayed hypersensitivity reactions in sensitised guinea pigs. A range of polysaccharides from other sources was tested in guinea pigs sensitised to dermatophytes. None gave delayed reactions, but some with structural features in common with those isolated from dermatophytes gave immediate reactions.

The growth of 9 species of keratinophilic fungi belonging to the genera Keratinomyces, Microsporum, Trichophyton and Epidermophyton was studied in vitro on hair, hedgehog spine, nail and callus. On hair digestion is carried out primarily by means of flat fronds of eroding mycelium which first life the cuticular scales and then erode the cortex. The well-known perforating organs arise from these fronds and in their turn may prouce further eroding mycelium which grows longitudinally through the cortex of the hair. The mechanism of penetration by perforating organs is discussed and a special study of T. rubrum showed that its method of attack on hair does not differ fundamentally from that of other keratinophilic fungi.It is also by means of fronds of eroding mycelium growing between the layers of keratinised cells that these fungi digest nail and hedgehog spine. Perforating organs are produced on both substrates by certain species. Eroding mycelium is uncommon in the softer keratin of callus.As frond-like m...

A survey has been made of the strains of Trichophyton rubrum occurring in a mycological diagnostic service during the 9 years of its existence. The great majority of the 265 isolates investigated could be assigned to the type Trichophyton (Epidermophyton) rubrum (Castellani, 1910) but 3 other described strains were also found, together with 2 hitherto underscribed. In addition, 1 strain intermediate between T. rubrum and T. mentagrophytes (interdigitale type) is discussed.

Dermatophytoses were investigated among white and Bantu patients at Dermatology Clinics in Bloemfontein between October 1970 and March 1973. Tinea capitis occurred predominantly in Bantu children and tinea corporis was found most often in white children. Trichophyton violaceum and Microsporum canis were the most frequent causes of these conditions. Tinea pedis and cruris were found almost exclusively in white adults and were more common in males than in females. Trichophyton interdigitale, Epidermophyton floccosum and Trichophyton rubrum, in that order of frequency, were the causative agents of these conditions. Favus due to Trichophyton schoenleinii occurred but was found only in Bantu children. Infections caused by Trichophyton mentagrophytes, Microsporum audouinii and Microsporum gypseum were very rare.

Human isolates of Microsporum gypseum, M. canis, Trichophyton mentagrophytes, T. tonsurans, T. rubrum and Epidermophyton floccosum were cultured in Sabouraud's medium and Kuehn's medium. The nondialyzable proteins of the culture filtrates and the mycelial mats were fractionated by disc electrophoresis. Characteristic electrophoretic patterns with 8 to 15 distinct protein fractions were obtained from each preparation. Comparisons among the species were made using the findings of each preparation from each medium. In each of the 4 comparisons a high number of homologous fractions was present in M. gypseum and M. canis and in T. mentagrophytes and T. tonsurans, and a high number of specific fractions was exclusively present in E. floccosum. These data are consistent with conventional taxonomic classification of the dermatophytes. Electrophoretic analysis of the dermatophytes may provide a new group of taxonomic characteristics complementing classical taxonomy.

Between July 1964 and March 1966 522 superficial fungal pathogens have been isolated from man, animals and soil in rural areas around Vellore, Madras State. Most of the isolates have been recovered from man: tinea corporis (334) tinea capitis (149), tinea unguium (27), interdigital clefts (7). The following species have been found: T. rubrum (163), T. violaceum (153), T. mentagrophytes (56), T. tonsurans (48), C. albicans (46), E. floccosum (44).The only zoophilic species found in man were T. mentagrophytes var. mentagrophytes (3) and T. simii (4). Three of the latter were typed as strains of Arthroderma simii. T. verrucosum (3) has been isolated from cattle and M. gypseum (2) from soil.The results indicate that tinea capitis is more frequent in India than hitherto supposed and that zoophilic fungi are less commonly found in man in rural areas than has been previously suggested.

Over a 5 year period (1975-1979) 746 dermatophytes were isolated from 4,234 patients examined in the Wellington area of New Zealand. Trichophyton rubrum was the predominant isolate, although the Microsporum canis isolation rate was also high, especially in children.

Thirty-two cases of dermatophyte infection in the external auditory meatus are reported. All the patients complained of slight itching or accumulation of cerumen; however, they had no other serious complaints. Otoscopy revealed lesions in the outer third of the ear canal. The skin of the meatus externus osseus and the surface of the tympanic membrane were all intact. In all cases, mycelial elements were demonstrated in KOH mounts of scrapings, and Trichophyton rubrum (29 cases), Microsporum canis (2 cases), and Epidermophyton floccosum (1 case) were isolated. All patients had ringworm of the pinna at the time of examination or in the past.