Keratinolysis by poultry farm soil fungi

Two hundred and eleven dogs (including strictly house and stray dogs) and 170 cattle in and around the city of Madras, India were screened for the presence of dermatophytosis. 106 strains of dermatophytes (89 strains from dogs and 17 strains from bovines) were isolated. 57/106 strains were Trichophyton mentagrophytes var. mentagrophytes and 42/106 strains were of the Microsporum gypseum complex. 5 strains of T. rubrum and 2 strains of T. simii were also obtained in culture. A predominance of M. gypseum complex isolates was recorded in stray dogs and cattle and T. mentagrophytes var. mentagrophytes and T. rubrum in strictly house dogs. The family history of the owners of the most of the dogs had clear records of dermatophytosis. Further, the owners of the 11 dogs that yielded T. mentagrophytes var. mentagrophytes had either tinea corporis or tinea pedis. The etiological agent of all the 11 human cases was T. mentagrophytes var. interdigitale. Similarly the owners of 4 of the 5 dogs that yielded T. rubrum were known T. rubrum patients. All these patients responded to oral griseofulvin or ketaconozole, but the recurrence of lesions was noted with the cessation of treatment. None of the patients had onychomycosis and the family history of all the patients revealed no reports of T. rubrum infections. The pet dogs were presumed to be the source of re-infection. Reversed transmission of dermatophytes from humans to animals may be the reason for the selective predominance of these organisms in strictly house dogs. They also may act as sources of reinfection. Most of the animals had small, occult, scattered lesions. These lesions may either go unnoticed or are ignored by the owners of the animals. The taxonomic status of T. mentagrophytes var. mentagrophytes and T. mentagrophytes var. interdigitale was aligned to their teleomorph Arthroderma vanbreuseghemii. Our study suggests that the periodic screening and medication of all live-stock are essential for the prevention and management of the public health problem caused by dermatophytes. This revised version was published online in August 2006 with corrections to the Cover Date.     

Prevalence of dermatophytes and yeasts (Candida spp., Malassezia furfur) in HIV patients

The prevalence of dermatophytes and yeasts (Candida spp. and Pityrosporum spp.) was studied in 40 former drug-addicts, all of whom were HIV seropositive but otherwise had no other symptoms (2nd Stage CDC Atlanta, 1987). We considered 7 skin areas for dermatophytes and Pityrosporum spp. (scalp, forehead, nose, back, chest, groin, toe webs) and the mouth for yeasts. Dermatophytes were found in 8 (20%) and tinea pedis was the most common dermatophytosis: Tricophyton rubrum was the fungus most frequently isolated (6 cases or 15%). The HIV + group showed almost the same rate of dermatophytes colonisation compared to a group of 121 athletes and to the control group. Candida spp. was present in 27 cases (67.5%) but clinical oral lesions were evident only in 5 patients (12.5%). Statistically significant differences were found in the presence of Candida spp. in HIV patients and controls (p<0.05). The lipophilic yeast Pityrosporum ovale was evaluated with quantitative and qualitative methods. Quantitative variations were evident between HIV patients and controls. P. ovale was present in 10 cases: 3 (7.5%) of them showed dischromic lesions while in 7 cases (17.5%) no clinical symptoms were evident.     

A survey of dermatophytes from human patients in the United States from 1985 to 1987

A survey of dermatophytes isolated from patients seeking medical advice was made from 1985 to 1987 in the United States. The survey included 54 locations with data from 45 cities and one state. Listing of the isolated dermatophytes and the frequency given by percentage of the total follows: Trichophyton rubrum 54.8%, T. tonsurans 31.3%, T. mentagrophytes 6.0%, Microsporum canis 4.0%, Epidermophyton floccosum 2.0%, M. gypseum 0.6%, and T. verrucosum 0.2%. Out of a total of 14,696 isolates M. audouinii was cultured 13 times, T. violaceum 12 times, M. nanum 6 times, T. terrestre 4 times, and T. soudanense twice. Single isolations were made of M.fulvum, M. ferrugineum and T. schoenleinii.Collection of dermatophyte data in Tucson, Arizona, began in 1966. In 1987, the first case of tinea capitis caused by T. tonsurans was observed. Other isolates of this organism as the cause of tinea capitis were made in this city during that year. These infections were in black children. With the recent growth of Tucson, the percentage of blacks in the population increased and this pathogen was introduced into the general population.     

Keratinophilic fungi on the hair of cows,donkeys, rabbits,cats, and dogs from the West Bank of Jordan

The mycoflora of hair of 111 cows, donkeys, rabbits, cats, and dogs were analysed and the frequency of occurrence and the relative importance value of the different fungal species isolated were calculated. Total numbers of species 56, 45, 48, 23, and 11 were recovered from cows, donkeys, rabbits, cats, and dogs respectively. The majority of the keratinophilic fungi isolated were either well-known mycotic agents or have been recovered from various animal and human lesions. These comprised 87.8%, 66.7%, 61.4%, 59.3%, and 55.2% of the hair mycoflora in cats, dogs, rabbis, cows, and donkeys respectively. Seven species of dermatophytes were isolated: Trichophyton mentagrophytes, T. verrucosum, Microsporum gypseum, M. nanum, T. ajelloi, and M. canis. Cats harboured the largest number of dermatophytes (5 species), followed by cows (4 spp), rabbits (3 spp), and donkeys and dogs (1 sp). The role of these animals in the persistence and transmission of pathogenic fungi is discussed.     

Isolation of keratinophilic fungi from floor dust in Arab elementary and preparatory schools in the West Bank of Jordan

Floor dust collected from classrooms of thirty three elementary schools (16 for girls, and 17 for boys) (children aged 6–11), and twenty four preparatory schools (13 for girls, and 11 for boys) (children aged 12–14) was studied for the occurrence of keratinophilic fungi with respect to human presence and age of children. Tichophyton mentagrophytes was present in 15.4% of the preparatory schools for girls, in 12.5% of elementary schools for girls, and in 11.8% of elementary schools for boys. It was not found in preparatory schools for boys. Microsporum gypseum was found in preparatory schools for girls only (7.7%). Trichophyton terrestre was also only isolated from elementary schools for boys (5.9%). Chrysosporium species were present in 30.3% of all elementary schools (10 schools/33), and in 20.8% of all preparatory schools (5 schools/24). Geotrichum candidum was the most frequent and predominant keratinophilic species in all schools. Pathogenic and potentially pathogenic keratinophilic fungi comprised a large proportion of all fungal isolates recovered from all schools ; they comprised 87.2 %–89.5 % of all fungal isolates in the elementary schools, and 90.4%–93.5% of all fungal isolates in preparatory schools.     

实验动物皮肤病原真菌DNA快速少量提取法

PCR技术应用于实验动物皮肤病原真菌检测,方法简单、省时。但是,真菌的DNA提取较为困难。本文推荐一种既简单又经济快速的提取皮肤真菌DNA的方法,并能成功用于实验动物皮肤病原真菌质量检测研究。     

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.

     

Onychomycosis in Tehran,Iran: Prevailing fungi and treatment with itraconazole

A total of 187 Patients with suspected onychomycosis were examined for causative fungal agents between 1996 and 1997. Laboratory examination confirmed onychomycosis in 115 patients, of which 97 cases were presented with positive microscopic and cultural examinations, and they were selected for itraconazole pulse therapy. From an etiological point of view, 48.4% of the nail infections, mainly toenail infections, were caused by dermatophytes, 43.3% were infected with Candida spp, specially infected fingernails, and 8.2% by non-dermatophytic molds. Trichophyton mentagrophytes var. interdigital and T. violaceum were the most prevalent species. Candida albicans and C. parapsilosis were the predominant species of the Genus Candida. Scopolariopsis brevicaulis was the most common non-dermatophyte molds observed. Female affected more frequently than male and in both sexes, those who were 30–49 years old, more infected. Toenails were affected more frequently than fingernails. In this study, itraconazole pulse therapy (400 mg daily) gave during the first week of per month for 3 months. The study included 51 patients with toenail onychomychosis (group 1) and 46 patients with fingernail infections (group 2). Patients were followed up for 9 months after the last treatment. Clinical response rates were 83% in the group 1, 95% in the group 2 at month 12; the corresponding mycological cure rates were 71 and 87%, respectively. This revised version was published online in June 2006 with corrections to the Cover Date.     

Major challenges and perspectives in the diagnostics and treatment of dermatophyte infections

Dermatophytes are the aetiological factors of a majority of superficial fungal infections. What distinguishes them from other pathogenic filamentous fungi is their unique ability to degrade keratin. The remarkable ability of this group of fungi to survive in different ecosystems results from their morphological and ecological diversity as well as high adaptability to changing environmental conditions. Paradoxically, despite the progress in medicine, the prevalence of dermatophyte infections is increasing from year to year. At the beginning of the third millennium, practical diagnostic and therapeutic options are still very limited. This review focuses on understanding the major problems in this aspect of dermatophyte infections and indicates future strategies and perspectives for novel approaches to identification and drugs for elimination of dermatophytes. Particular importance is placed on development of a strategy for a diagnostic pathway and implementation of rapid and reliable diagnostics methods designed by international teams. Furthermore, among compounds that currently arouse great interest, representatives of terpenoids, alkaloids, saponins, flavonoids and essential oils deserve attention. Many of these compounds are undergoing clinical trials as potential antifungal agents, and future research should focus on attempts at determination of the applicability of tested substances. Finally, the advantages and disadvantages in implementation of new diagnostic paths and medicinal substances for routine use are indicated.