Dermatophytosis caused by <Emphasis Type="Italic">Microsporum canis</Emphasis> in Eastern cottontail (<Emphasis Type="Italic">Sylvilagus floridanus</Emphasis>)

Eastern cottontail (Sylvilagus floridanus, fam. Leporidae) has previously been shown to be a potential healthy carrier of dermatophyte fungi both geophilic (Microsporum gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes). In this communication, the first case, to the best of our knowledge, of a symptomatic dermatophyte infection in S. floridanus is described.     

Dermatophytes isolated from patients in University Hospital,Kuala Lumpur,Malaysia

A total of 576 dermatophytes were isolated from patients with a variety of skin infections from January 1993 to May 2000. Ten species of dermatophytes were identified: Epidermophyton floccosum (0.7%), Microsporum audouinii (1.1%), M. canis (3.1%), M. gypseum (0.3%), Trichophyton concentricum(3.5%), T. equinum (0.2%), T. mentagrophytes (36.%), T . rubrum (53.8%), T. verrucosum (0.2) and T. violaceum (1.0%). The body sites most frequently affected by dermatophytes were the buttocks, nails and trunk. Anthropophilic dermatophytes made up 60.1% of the isolates; the most common species was T. rubrum, T. mentagrophytes and M. canis were the two main zoophilic dermatophytes. T. mentagrophytes was isolated from all body sites except the scalp. M. canis was found to be associated with domestic dogs and wasnot isolated from ethnic Malays. The only geophilic dermatophyte was M. gypseum, an uncommon dermatophyte associated with tinea pedis.This revised version was published online in October 2005 with corrections to the Cover Date.     

Chicory extracts from Cichorium intybus L. as potential antifungals

In this work extracts from roots of the common vegetable Cichorium intybus L., highly appreciated for its bitter taste, were studied to investigate their possible biological activity on fungi from a variety of ecological environments: some are parasites on plants (phytopathogens) or of animals and humans (zoophilic and anthropophilic dermatophytes), others live on the soil and only seldom parasitize animals (geophilic dermatophytes). The extracts were ineffective on geophilic species and on tested phytopathogens, with the exception of Pythium ultimum, whereas they inhibited the growth of zoophilic and anthropophilic dermatophytes, in particular Trichophyton tonsurans var. sulfureum, whose treatment caused morphological anomalies, here observed by scanning electron microscopy. This behaviour is discussed on the basis of the presence in the chicory extract of the two main sesquiterpene lactones, 8-deoxylactucin and 11β,13-dihydrolactucin.     

Antifungal potential of essential oil and various organic extracts of <Emphasis Type="Italic">Nandina domestica</Emphasis> Thunb. against skin infectious fungal pathogens

This study was undertaken to assess the in vitro antifungal potential of the essential oil and n-hexane, chloroform, ethyl acetate, and methanol extracts of Nandina domestica Thunb. against dermatophytes, the casual agents of superficial infections in animals and human beings. The oil (1,000 μg/disc) and extracts (1,500 μg/disc) revealed 31.1–68.6% and 19.2–55.1% antidermatophytic effect against Trichophyton rubrum KCTC 6345, T. rubrum KCTC 6375, T. rubrum KCTC 6352, Trichophyton mentagrophytes KCTC 6085, T. mentagrophytes KCTC 6077, T. mentagrophytes KCTC 6316, Microsporum canis KCTC 6591, M. canis KCTC 6348, and M. canis KCTC 6349, respectively, along with their respective minimum inhibitory concentration values ranging from 62.5 to 500 and 125 to 2,000 μg/ml. Also, the oil had strong detrimental effect on spore germination of all the tested dermatophytic fungi as well as concentration and time-dependent kinetic inhibition of T. rubrum KCTC 6375. The present results demonstrated that N. domestica mediated oil and extracts could be potential sources of natural fungicides to control certain important dermatophytic fungi.     

A short review on dermatophytoses of animals in Romania

Dermatophytoses of animals in Romania are reviewed. Ringworm infections have been found in cattle (whereT. verrucosum was the only isolated agent), horses (the causative organisms beingT. verrucosum, T. mentagrophytes andM. equinum), cats (dermatophytes isolated:M. canis andT. quinckeanum), dogs (M. canis andM. gypseum), fowlsT. gallinae). From the laboratory animals: guinea pigs (T. mentagrophytes, M. audouinii, T. rubrum), mice (T. quickeanum andT. mentagrophytes), rats (T. mentagrophytes), rabbits (T. mentagrophytes andM. canis) and hamster)T. mentagrophytes). Among the wild animals, only the chamois had a ringworm infection byM. gypseum, other large or smaller wild animals harboring only saprophytically some poozhilic and geophilic dermatophytes.     

Dermatophytes isolated from symptomatic dogs and cats in Tuscany,Italy during a 15-year-period

Between January, 1, 1986 and December, 31, 2000, dermatological specimens from 10.678 animals (7.650 cats and 3.028 dogs) were examined for dermatophytes. All the animals presented clinical signs of ringworm. Two thousand-four hundred fifty-six of the 10.678 (23%) examined animals scored positive for dermatophytes, 566 out of 3.028 canine (18.7%) and 1890 out of 7.650 feline specimens (24.7%). Microsporum canis constituted 83% and 97% of the isolated dermatophytes respectively in dogs and cats, M. gypseum represented 13% and 2.6% and T. mentagrophytes 5.5% and 0.2%. A sexual predisposition for mycotic infections was not observed. The animals with less than 1 year of age were more frequently infected. Canine toy breeds showed a significantly higher (P < 0.001) prevalence of infections by M. canis. Microsporum gypseum was mostly recorded from sporting (hunting) breeds [such as T. mentagrophytes (6.7%)]. Microsporum canis was isolated from long-haired cats with a ratio of 2:1 versus short-haired cats, while M. gypseum and T. mentagrophytes were never recovered from Persian cats. The annual distribution of the infections in dogs showed a significantly higher incidence for M. gypseum in summer versus winter and spring, while the recovery rate of M. canis from cats was very significantly higher in fall and winter than in summer and spring. Trichophyton mentagrophytes did not show a similar seasonal distribution.This revised version was published online in October 2005 with corrections to the Cover Date.     

Favus of the Scalp: An Overview and Update

Tinea capitis favosa, a chronic inflammatory dermatophyte infection of the scalp, affects over 90% of patients with anthropophilic Trichophyton schoenleinii. T. violaceum, T. verrucosum, zoophilic T. mentagrophytes (referred to as ‘var. quinckeanum’), Microsporum canis, and geophilic M. gypseum have also been recovered from favic lesions. Favus is typically a childhood disease, yet adult cases are not uncommon. Interestingly, favus is less contagious than other dermatophytoses, although intrafamilial infections are reported and have been widely discussed in the literature. Clinical presentation of T. schoenleinii infections is variable: this fungus can be isolated from tinea capitis lesions that appear as gray patches, but symptom-free colonization of the scalp also occurs. Although in the past T. schoenleinii was the dominant fungus recovered from dermatophytic scalp lesions, worldwide the incidence has decreased except in China, Nigeria, and Iran. Favus of the glabrous skin and nails are reported less frequently than favus of the scalp. This review discusses the clinical features of favus, as well as the etiological agents, global epidemiology, laboratory diagnosis, and a short history of medical mycology.     

Dermatophytes in a population of bank voles and woodmice

A population of bank voles (Clethrionomys glareolus) and wood mice (Apodemus sylvaticus) inhabiting an oak wood in Somerset was examined for dermatophytes at monthly intervals for 2 years. The marked animals were frequently retrapped, allowing a study of host fungus relationship over a period of time. Microsporum persicolor (Sabouraud) Guiart er Grigorakis and Trichophyton mentagrophytes (Robin) Blanchard were isolated from both animal species, but M. persicolor predominated in bank voles and T. mentagrophytes in wood mice. In their most favoured host, both dermatophyte species often persisted for several months, but in the less favoured host they were never isolated at more than one sampling. Males of both animal species were infected more often than females.The existing evidence for the geophilic nature of both fungi is reviewed and shown to be very weak, especially for M. persicolor.This is the first report from Great Britain of T. mentagrophytes infection of wood mice not in contact with human habitation.     

SDS-PAGE separation of dermatophyte antigens,and western immunoblotting in feline dermatophytosis

Water-soluble antigens liberated from the disrupted mycelium of nine dermatophytes (seven isolates ofMicrosporum canis, one each ofMicrosporum gypseum andTrichophyton mentagrophytes) were compared by analytical slab SDS-PAGE. No substantial differences were observed between the protein bands of theM. Canis isolates, but certain distinctive bands were apparent in the other two species examined. Western immunoblotting usingM. canis-derived antigens separated by SDS-PAGE was used to investigate the humoral immune response in 79 cats with naturally-occurring dermatophytosis (72 withM. canis, six withM. gypseum and one withT. mentagrophytes) and this information was compared to results of immunoblots from 46 control (non-dermatophyte exposed) cats. Seven dominant bands (bands which occurred frequently and stained heavily) were identified in immunoblots from the dermatophyte-infected cats with apparent molecular weights varying between 39 and 120 kD. None of these bands were totally specific markers for dermatophytosis as a variable proportion of the control cats showed reactivity to all these proteins. However, most (73%) of the dermatophyte-infected cats showed reactivity to six or seven of the identified bands whereas most (80%) of the control cats showed reactivity to between zero and three of these bands (p<0.005). Western immunoblotting could be used to select individual immunodominant antigens for further evaluation of protective (cell-mediated) immunity.     

Ex vivo biofilm-forming ability of dermatophytes using dog and cat hair: an ethically viable approach for an infection model

The aim of this study was to establish an ex vivo model for dermatophyte biofilm growth, using hair from dogs and cats. Strains of Microsporum canis, M. gypseum, Trichophyton mentagrophytes and T. tonsurans were assessed for in vitro and ex vivo biofilm production. All T. mentagrophytes and T. tonsurans isolates and 8/12?M. canis and 1/7?M. gypseum isolates formed biofilms in vitro, while all tested isolates presented biofilm growth on ex vivo models. T. mentagrophytes and M. canis formed more homogeneous and better-structured biofilms with greater biomass production on cat hair but T. tonsurans formed more biofilm on dog hair. Confocal and scanning electron microscopy demonstrated fungal hyphae colonizing and perforating the hair shaft, abundant fungal conidia, biofilm extracellular matrix and biofilm water channels. The present study demonstrated an ex vivo model for the performance of studies on biofilm formation by dermatophytes, using dog and cat hair.     

Dermatophytes and other keratinophilic fungi from coypus (Myocastor coypus) and brown rats (Rattus norvegicus)

The occurrence of mycotic agents was investigated by hair-brush technique on the coat of 162 naturalized coypus (Myocastor coypus) and 64 indigenous brown rats (Rattus norvegicus) originating from the same protected area in Central Italy. The isolates from positive coypus (29.6%) were identified as Microsporum gypseum (14.8%), Trichophyton terrestre (9.8%), Alternaria sp. (3.7%), Trichophyton mentagrophytes (2.5%), Cladosporium sp. (1.8%), Scopulariopsis sp. (1.2%), and Chrysosporium keratinophilum (0.6%), whereas the isolates from positive rats (46.7%) were identified as M. gypseum (28.1%), T. mentagrophytes (12.5%), Chrysosporium tropicum and T. terrestre (3.1% each), and Chrysosporium inops (1.6%). Statistically, brown rats were more likely to harbor fungal agents (P < 0.05) on their coat than coypus, especially T. mentagrophytes (P < 0.01) and M. gypseum (P < 0.05). No positive animal showed dermatological lesions. The present results are the first providing basic information on the coat’s mycoflora of a wild coypu population. It is concluded that the coypu, an allochthonous rodent in Italy, can play a role as natural animal reservoir of dermatophytes and as carrier of keratinophilic and saprophytic fungi within its new habitat, though to a lesser extent than indigenous rats. Therefore, people who are exposed to the risk of contact with the coat of rats and coypus should take all the cautions needed to protect themselves from mycotic agents potentially transmissible to humans.     

Epidemiology of the dermatophytoses in the Florence area of Italy: 1985–1990

Between 1985 and 1990 we observed 2085 cases of dermatophytoses in the Florence area of Italy.Trichophyton rubrum andMicrosporum canis were the major etiological agents. 126 cases of dermatophytoses observed during this period were caused byTrichophyton mentagrophytes. Most of the patients came from rural areas or they kept pets.Epidermophyton floccosum ranked fourth in frequency (95 cases). The patients were adults and mainly males, most of whom engaged in sports or lived in group environments.Microsporum gypseum was isolated in 31 cases. Infections occurred directly from contact with soil or domestic animals. We report the principal clinical data concerning these last three dermatophyte infections.     

Influencia del grupo ecológico sobre la sensibilidad in vitro de los hongos dermatofitos a los antifúngicos

BackgroundDermatophytes 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.AimsThe 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.MethodsA 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.ResultsThe in vitro antifungal activity was different depending on the ecological group, although a species-dependent profile was also observed.ConclusionsAzole 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.     

Isolations of dermatophyte from clinically normal scalps inM. Canis infections using the hairbrush method

The scalp hair of patients with dermatophytosis due toM. canis but without scalp lesions, and that of their family members without dermatophytosis were examined using the hairbrush method. The dermatophyte was detected in 93.8% of the scalps of those who lived in homes where cats were kept, and in 25% of those without cats. After the source of infection had been treated, the dermatophyte showed a gradually decreasing presence, finally disappearing altogether, so that no case of the disease on the scalp hair could be found.We inferred from the above findings inM. canis infections that, since the dermatophytes are seen in a high proportion of cases without scalp lesions, the dermatophytes, in many cases, exist only as saprophytes on the hair.     

Characterization of siderophores produced by different species of the dermatophytic fungiMicrosporum andTrichophyton

The dermatophytic fungiTrichophyton spp andMicrosporum spp secrete ferrichrome type siderophores under low iron conditions. Three different species ofMicrosporum, i.e.M. qypseum, M. canis andM. audouinii, as well asT. rubrum produce ferrichrome C and ferricrocin, whereasT. mentagrophytes andT. tonsurans produce only ferrichrome. The identification of the siderophores was established by means of thin layer chromatography, high performance liquid chromatography and mass spectroscopy.     

Review of dermatophytoses in Galicia from 1951 to 1987, and comparison with other areas of Spain

We have reviewed all the dermatophytoses diagnosed in Galicia during four consecutive 9-year periods 1951–86 and 1987. From 4571 patients, we isolated 3351 fungal strains belonging, in decreasing order of frequency, to the following dermatophyte species: Microsporum canis (25.5%), Trichophyton rubrum (24.6%), T. mentagrophytes (21.4%), Epidermophyton floccosum (11.8%), M. gypseum (5.2%), T. tonsurans (3.9%), T. verrucosum (3.1%), T. schoenleinii (2.5%), T. violaceum (1.2%), T. mengninii (0.3%), M. audouinii (0.2%), T. equinum (0.1%) and T. soudanense (0.1%). Tinea capitis has diminished in frequency since 1951, though there was been a slight increase since 1978; M. canis has always been the most common agent, and between 1951 and 1959 T. schoenleinii was also very frequent but is no longer found. The frequency of tinea corporis, on the other hand, has experienced a considerable increase. Its most common causal agents in the last few years have been T. mentagrophytes, M. canis and T. rubrum. Until 1977 the most common tinea cruris dermatophyte was E. floccosum, but since then it has been T. rubrum. The commonest tinea pedis dermatophytes have been T. rubrum and T. mentagrophytes. Tinea unguium and tinea barbae have been the most frequent dermatophytoses, and their commonest causal agents T. rubrum and T. mentagrophytes respectively. We have documented the distribution of the various causal agents by location of the lesions, age and source of the patients (private or National Health Service patients), and we have compared the results with those obtained in other regions of Spain.     

Dermatophyte and non dermatophyte fungi in Riyadh City,Saudi Arabia

BackgroundDermatophytes are a scientific label for a group of three genera (Microsporum, Epidermophyton and Trichophyton) of fungus that causes skin disease in animals and humans. Conventional methods for identification of these fungi are rapid and simple but are not accurate comparing to molecular methods.ObjectiveThis study aimed to isolate human pathogenic dermatophytes which cause dermatophytosis in Riyadh City, Saudi Arabia and to identify these fungi by using conventional and molecular methods.MethodsThe study was conducted in Medical Complex, Riyadh and King Saud University. Samples of infected skin, hairs and nails were collected from 112 patients. Diagnosis of skin infections, direct microscopic test, isolation and identification of dermatophytes by conventional and molecular methods were carried out.ResultsThe results indicated that the tinea capitis infection had the highest prevalence among the patients (22.3%) while Tinea barbae had the lowest. In this study the identified dermatophyte isolates belong to nine species as Trichophyton violaceum, Trichophyton verrucosum, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton schoenleinii, Trichophyton concentricum, Microsporum canis, Microsporum audouinii and Epidermophyton floccosum which cause skin infections were isolated during this study. Non dermatophyte isolates included 5 isolates from Aspergillus spp. 4 isolates from Acremonium potronii and 15 isolates from Candida spp. M. canis were the most common species (25% of isolated dermatophytes). Out of the 52 dermatophyte isolates identified by conventional methods, there were 45 isolates identified by the molecular method.ConclusionsThe results concluded that approximately M. canis caused a quarter of dermatophyte cases, tinea capitis infection was prevalent and the molecular method was more accurate than conventional methods.     

Dermatophytes isolated from patients in University Hospital,Kuala Lumpur,Malaysia

A total of 576 dermatophytes were isolated from patients with a variety of skin infections from January 1993 to May 2000. Ten species of dermatophytes were identified: Epidermophyton floccosum (0.7%), Microsporum audouinii (1.1%), M. canis (3.1%), M. gypseum (0.3%), Trichophyton concentricum (3.5%), T. equinum (0.2%), T. mentagrophytes (36.1%), T. rubrum (53.8%), T. verrucosum (0.2) and T. violaceum (1.0%). The body sites most frequently affected by dermatophytes were the buttocks, nails and trunk. Anthropophilic dermatophytes made up 60.1% of the isolates; the most common species was T. rubrum, T. mentagrophytes and M. canis were the two main zoophilic dermatophytes. T. mentagrophytes was isolated from all body sites except the scalp. M. canis was found to be associated with domestic dogs and was not isolated from ethnic Malays. The only geophilic dermatophyte was M. gypseum, an uncommon dermatophyte associated with tinea pedis.     

A survey of dermatophytes isolated from human patients in the United States from 1982 to 1984

A survey of dermatophytes isolated from patients seeking medical advice was made from 1982 to 1984 in the United States. The survey included 59 locations with data from 49 cities and one state. Listing of the isolated dermatophytes and the frequency given by percentage of total follows: Trichophyton rubrum 46.8%, T. tonsurans 33.3%, T. mentagrophytes 10.1%, Microsporum canis 4.5%, Epidermophyton floccosum 3,5%, M. gypseum and T. verrucosum both 0.7%, M. audouinii and T. terrestre both 0.1%, and T. violaceum 0.06%. No isolations of M. ferrugineum or T. schoenleinii were reported.Temporal increases were observed for frequencies of T. mentagrophytes, T. tonsurans and M. canis, and decreases occurred for frequencies of E. floccosum and T. rubrum when the data from this survey were compared by the goodness of fit test to data of the 1979 to 1981 survey. The percent of dermatophyte isolations identified as T. tonsurans correlated significantly with the percentage of blacks in cities of 100000 or more people.     

Etude sur la contamination par les champignons dermatophytes d'une population de petits mammiferes sauvages en Alsace

Résumé Des 3782 petits mammifères sauvages capturés au cours d'une enquête poursuivie pendant plus de 4 ans, 15,78% sont contaminés par des dermatophytes.Les espèces de dermatophytes ou champignons, apparentés qui sont rencontrées ne sont que 6;Microsporum persicolor etTrichophyton mentagrophytes sont les espèces dominantes. Les campagnols roussâtres sont, de façon significative, plus contaminés parM. persicolor (11,63%) que parT. mentagrophytes (4,36%). Au contraire, les mulots sont plus contaminés parT. mentagrophytes: 13,95% contre 3,50% contaminés parM. persicolor. Les campagnols roussâtres mâles (13,33%) sont plus contaminés que les femelles (9,45%) parM. persicolor et les mulots mâles (17,09%) plus contaminés que les femelles (9,95%) parT. mentagrophytes. La présence deM. persicolor est notée pour la première fois chez le grand hamster. L'étude histologique de certains animaux permet de remarquer l'existence de lésions dermatophytiques. A l'isolement deT. mentagrophytes correspond une attaque pilaire de type endo-ectothrix; à l'isolement deM. persicolor correspond une attaque limitée à l'épiderme.

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3782 small wild mammals trapped during a 4 year survey have been examined in relation to a possible contamination by dermatophytes. 15.78% of the animals were contaminated.The prevailing species wereMicrosporum persicolor andTrichophyton mentagrophytes. The bank voles were significantly more contaminated byM. persicolor (11.63%) than byT. mentagrophytes (4.36%). On the contrary the wood mice were more contaminated byT. mentagrophytes: 13.95% as against 3.50% contaminated byM. persicolor. The male bank voles (13.33%) were more contaminated than the females (9.45%) byM. persicolor and the male wood mice (17.09%) more contaminated than the females (9.95%) byT. mentagrophytes. The occurrence ofM. persicolor in common hamster is noted for the first time. The existence of a pathological lesion in relation to the fungal contamination was noted in the small group of rodents examined histologically: WhenT. mentagrophytes was isolated the hairs were invaded in the endo-ectothrix type pattern; whenM. persicolor was cultivated, hairs are not attacked but only the epidermis.