Use of arbitrarily primed polymerase chain reaction to differentiate Trichophyton dermatophytes

Abstract Dermatophytes such as Trichophyton species are common human pathogens, the infection of which results in dermatophytosis (also known as ringworm). Several laboratory tests are used routinely for the diagnosis of dermatophytosis, but they are either slow or lacking specificity. Through examination of genomic DNA from Trichophyton dermatophytes and other fungi in arbitrarily primed PCR, it was shown that a random primer 5'-ACCCGACCTG-3' produced bands of 4.3 kb, 1.9 kb, 1.7 kb and 0.7 kb in T. rubrum DNA, bands of 2.5 kb, 1.9 kb and 0.8 kb in T. mentagrophytes var. interdigitale and T. mentagrophytes var. mentagrophytes DNA, and bands of 2.5 kb, 1.9 kb, 1.5 kb and 0.9 kb in T. tonsurans DNA. This primer amplified bands of different sizes in other fungal DNA. Therefore, based on the distinct band patterns observed in arbitrarily primed PCR using this primer, T. rubrum , T. mentagrophytes and T. tonsurans dermatophytes could be rapidly differentiated.     

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.     

Antagonistic activity of bacteria from Bacillus genus against dermatophyte fungi

Antagonistic properties of the strain Bacillus subtilis IB-54 with respect to dermatophyte fungi Trichophyton rubrum, T. mentagrophytes var. gypseum, Microsporum canis was studied. The studied strains of bacilli effectively inhibited growth and development of dermatophytes when were cultivated on the media containing different carbon sources. Experiments on laboratory animals showed that B. subtilis IB-54 displayed no virulence, toxicity, and toxigenicity and can be considered as perspective object for development of antimycotic drugs.     

126例面癣临床因素及病原菌分析

目的探讨面癣的致病菌种、临床特点及发病相关因素。方法对126例面癣患者进行真菌分离培养鉴定及流行病学分析。结果面癣见于各年龄段,以11～30岁最多见。患病动物接触史、合并其他部位浅部真菌病史及糖皮质类固醇激素类药物外用史是面癣发病的重要危险因素。分离出皮肤癣菌108株,包括红色毛癣菌63株（58．3％）、犬小孢子菌25株（23．1％）、须癣毛癣菌18株（16．7％）和石膏样小孢子菌2株（1．9％）。结论面癣的发病没有年龄差异,患者可见于各个年龄阶段;面癣的常见致病真菌绝大多数为红色毛癣菌和犬小孢子菌,其发病可能与患者自体接种或接触患病动物相关。面癣容易被误诊,及时进行真菌镜检和培养是降低面癣误诊率的关键。     

Clinical and epidemiological survey of dermatophytoses in Jaen (Spain)

Prevalence of dermatophytosis, with respect to age and sex and dermatophyte species, in Jaen was investigated during a period of three years (1996-1999). The prevalence of dermatophytosis over three years was 4.48 cases / 1000 inhabitants. The isolated species were: Microsporum canis (48.6%), Trichophyton mentagrophytes (27.1%), Epidermophyton floccosum (10%), Trichophyton rubrum (8.6%), Trichophyton violaceum (4.3%), and Microsporum gypseum (1.4%). The most frequently observed dermatophytoses were tinea corporis (62.8%), followed by tinea capitis (12.8%); other clinical forms encountered were, in decreasing order of frequency, tinea cruris, tinea pedis and tinea unguium, tinea faciei and tinea barbae. Men were more affected than women.     

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.     

Etiologic and epidemiologic study of dermatomycoses in Navarra (Spain)

We review the etiology of the dermatophytosis in Navarra (Spain) over a 5-year period and it is compared with previous studies. We have isolated 312 strains of dermatophyte fungi in 285 patients (188 men and 97 women). Trichophyton rubrum was the most frequently isolated species (58.6%) followed by Trichophyton mentagrophytes (26.2%) and Microsporum canis (10.5%). Concerning the location of the lesions, tinea pedis was the clinical pattern found in the greatest number of patients, followed by tinea corporis, tinea unguium and tinea capitis. Twenty eight percent of the isolations were accomplished in October and November. More than half of those patients questioned had had epidemiological contact with animals or practiced sports. The rise of tinea pedis in our region is emphasised. The possible causes of this increment are analyzed and some recommendations for its control are made.     

Dermatophytosis due to Trichophyton rubrum. Ten-year period (1996-2006) data collection in a Dermatology Department in Mexico City

Dermatophytosis is the most common mycosis in the world up to 80% caused by Trichophyton rubrum. The aim of the present study was to describe the clinical characteristics of the dermatophytosis caused by T. rubrum in a dermatological outpatient clinic during a ten years period, from 1996 to 2005. We collected the data from patients with a dermatophytosis from which we have isolated T. rubrum. A total of 776 patients with dermatophytosis caused by T. rubrum were found. A slight predominance of female patients (56.2%) was observed. The most commonly affected age group was those in the third to the fifth decade of life, and house working women (33.5%) were predominant. Onychomycosis was found in 63% of the cases, tinea pedis in 22.7%, tinea corporis in 5.2% and tinea cruris in 2.8%. In onychomycosis, the first toe nail was the most commonly affected (58.9%) and the dystrophic type was seen in 50.7% of them.     

Animal dermatophytosis. Recent advances

The proportion of positive samples in relation to the number of samples examined from cases of dog and cat dermatophytosis varies considerably from one investigation to another. In dogs, it ranges between 4% and 10% and few studies show higher prevalences. On the other hand, the percentages of positive cultures cited in the reviewed literature from dogs with or without suspected dermatophytosis are quite similar. In dogs with suspected lesions of dermatophytosis, with few exceptions, Microsporum canis is the most common species isolated. Trichophyton mentagrophytes and Microsporum gypseum are less frequently isolated. In cats the prevalence of dermatophytes is usually higher than in dogs, and it is usually higher than 20%. However the frequency of positive findings is higher in cats with suspected dermatophytosis than in cats without visible lesions, with the exception of asymptomatic infected cats and transient carrier cats. Cats are accepted as the principal reservoir for M. canis. Griseofulvin is the drug of choice in canine and feline dermatophytosis.     

Antimicrobial activity of Hyptis ovalifolia towards dermatophytes

The essential oil and the aqueous, hexane and methanolic fractions from Hyptis ovalifolia leaves were evaluated for their antifungal activity in vitro against 60 strains of dermatophytes: 10 strains of Microsporum canis, 10 of M. gypseum, 20 of Trichophyton rubrum and 20 of T. mentagrophytes. The extracts inhibited growth of the dermatophytes tested at different concentrations. The most biologically active was the essential oil from the leaves which inhibited 57 isolates (95%) at a concentration of 500 g/ml.     

Strains differentiation of Microsporum canis by RAPD analysis using (GACA)4 and (ACA)5 primers

Molecular analysis of dermatophytes (based on PCR fingerprinting) revealed high clonal differentiation between the genus and species. Microsporum canis (zoophilic dermatophyte, belonging to genus Microsporum), responsible for most cases of tinea capitis in children, tinea corporis in adults and dermatophytoses in cats, is very unique in comparison with other dermatophytes. Results of most molecular studies show that there is no clonal differentiation within M. canis as distinct from other species. The aim of this study was application of (GACA)4 repetitive primer and (ACA)5 primer for typing of M. canis strains isolated from human and animals in Central Poland. Fungal strains: 32 clinical isolates of M. canis, originated from patients from Central Poland; 11 strains isolated from infected cats (6) and dogs (7), reference strains of M. canis (CBS 113480), T rubrum (CBS 120358), T mentagrophytes (CBS 120357) and E. floccosum (CBS 970.95). The genomic DNAs of the strains were used as a template in RAPD reaction. No differentiation was observed for the analyzed M. canis strains using (GACA)4 and (ACA)5 typing.     

Saprophytic occurrence of Trichophyton mentagrophytes and Microsporum gypseum in the coats of healthy laboratory animals

A group of 199 healthy laboratory animals, comprising 63 guinea pigs; 58 white mice. 47 rats and 31 rabbits, was sampled for the presence of pathogenic dermatophytes. T. mentagrophytes, var. granulare, was isolated in 10% (5-guinea pigs, 6 mice, 6 rats and 2 rabbits) and M. gypseum was found in 7 animals (3 guinea pigs, 3 mice and one rat). No ringworm lesions were observed in the respective animals. This is the first report on such findings in Israel.     

Antifungal activities of the essential oils in Syzygium aromaticum (L.) Merr. Et Perry and Leptospermum petersonii Bailey and their constituents against various dermatophytes

This study was carried out in order to investigate the potential of using plant oils derived from Leptospermum petersonii Bailey and Syzygium aromaticum L. Merr. Et Perry as natural antifungal agents. The antifungal effects of essential oils at concentrations of 0.05, 0.1, 0.15, and 0.2 mg/ml on the dermatophytes Microsporum canis (KCTC 6591), Trichophyton mentagrophytes (KCTC 6077), Trichophyton rubrum (KCCM 60443), Epidermophyton floccosum (KCCM 11667), and Microsporum gypseum were evaluated using the agar diffusion method. The major constituents of the active fraction against the dermatophytes were identified by gas chromatography-mass spectrometry and high-performance liquid chromatography analysis. The antifungal activities of S. aromaticum oil (clove oil) against the dermatophytes tested were highest at a concentration of 0.2 mg/ml, with an effectiveness of more than 60%. Hyphal growth was completely inhibited in T. mentagrophytes, T. rubrum, and M. gypseum by treatment with clove oil at a concentration of 0.2 mg/ml. Eugenol was the most effective antifungal constituent of clove oil against the dermatophytes T. mentagrophytes and M. canis. Morphological changes in the hyphae of T. mentagrophytes, such as damage to the cell wall and cell membrane and the expansion of the endoplasmic reticulum, after treatment with 0.11 mg/ml eugenol were observed by transmission electron microscopy (TEM). At a concentration of 0.2 mg/ml, L. petersonii oil (LPO) was more than 90% effective against all of the dermatophytes tested, with the exception of T. rubrum. Geranial was determined to be the most active antifungal constituent of L. petersonii oil. Taken together, the results of this study demonstrate that clove and tea tree oils exhibited significant antifungal activities against the dermatophytes tested in this study.     

Studies in the Epidemiology of Tinea Pedis. IX: Tinea Pedis and Erythrasma in New Patients at a Chiropody Clinic

The feet of 259 new patients at a chiropody clinic were examined for tinea pedis, onychomycosis, and erythrasma: 23% of men and 4% of women were infected by dermatophytes, and the nails of seven males were infected by non-dermatophytes. Of 200 patients examined under Wood''s light 37% showed the coral-red fluorescence of erythrasma.Of the 259 patients, 9.7% were infected by Trichophyton interdigitale, 2.7% by T. rubrum, and 1.5% by Epidermophyton floccosum. Reasons are given, based on the method of selection of the patients, for supposing that T. interdigitale is still the dominant cause of tinea pedis in the population at large, despite figures from dermatological clinics suggesting the dominance of T. rubrum. The high incidence of infection in males compared with females corresponds with similar findings in school-children.     

Oral terbinafine for the tinea unguium of the toenails. Efficacy between 12 and 24 weeks of treament.

Terbinafine 250 mg po daily was administered to 21 patients affected by tinea unguium of the toenails. In 14 cases Trichophyton rubrum was the aetiological agent while Trichophyton mentagrophytes var. interdigitale affected the rest. The treatment was administered randomized during 12 or 24 weeks in two groups of 11 (group A) and 10 (group B) patients. The clinical and mycological response was evaluated at week 12, 24 and 48. Adverse events were registered during the therapeutic period. At week 24, 55.5% of patients from group A were cured, only one patient did not improve and cultures were positive. In group B 66.6% were cured and three were clinically improved but cultures were positive. In the last control after 48 weeks the results were similar except one patient of the group B who worsened of his nails lesions. Only one case of acute urticaria was noted, the symptoms disappeared after the withdrawal of terbinafine. Terbinafine per os is a safe and effective antifungal for the treatment of the tinea unguium of the toenails. A period of 12 weeks of administration is enough in most of cases but when T. rubrum is the aetiology relapse could be possible.     

面癣118例的真菌学和临床因素分析

目的探讨面癣的致病菌、临床特点、易感年龄等相关因素。方法分析本院门诊2012年1～6月的真菌直接涂片镜检发现菌丝或孢子的面癣患者。记录患者的一般资料、有无动物接触史、有无并发其他部位浅部真菌病、用药史。取皮屑直接镜检的同时进行真菌培养鉴定。结果面癣见于各年龄段,在51～70岁之间有一个年龄高峰。分离皮肤癣菌103株,包括红色毛癣菌70株(68.0%)、犬小孢子菌21株(20.4%)、须癣毛癣菌10株(9.7%)、石膏样小孢子菌2株(1.9%)。合并其他浅部真菌病、使用激素类药物、动物接触史是面癣发病的重要因素。部分炎症明显的面癣使用医用拭子取材,可以提高真菌涂片和培养的质量。结论不典型的面癣容易误诊,需要高质量的真菌镜检和培养,降低面癣误诊率。     

卡泊芬净、米卡芬净对8种皮肤癣菌体外抑菌活性的研究

目的评价棘白菌素类抗真菌药物卡泊芬净（caspofungin）、米卡芬净（micafungin）针对常见致病性皮肤癣菌的体外抗菌活性。方法参考CLSI制定的M38-A2方案。测定82株常见皮肤癣菌的最低有效浓度（minimal effective concentrations,MECs）。结果按照MEC90浓度从高到低,米卡芬净对紫色毛癣菌和断发毛癣菌的MEC90是0.25μg/mL;对犬小孢子菌、疣状毛癣菌的MEC90为0.06μg/mL;对红色毛癣菌、须癣毛癣菌、石膏小孢子菌、絮状表皮癣菌的MEC90均在0.03μg/mL。②卡泊芬净对红色毛癣菌、紫色毛癣菌和断发毛癣菌的MEC90为1μg/mL;对须癣毛癣菌、犬小孢子菌、石膏小孢子菌、絮状表皮癣菌和疣状毛癣菌的MEC90为0.5μg/mL。③根据中位数检验,米卡芬净对几种皮肤癣菌的MEC值均低于卡泊芬净的MEC值,统计学比较有显著性差异（P〈0.05）。结论米卡芬净和卡泊芬净对皮肤癣菌有较强的抑菌作用,米卡芬净的MEC值低于卡泊芬净。     

Immunology of dermatophytosis

By causing experimental lesions of dermatophytosis in rabbits inoculated and reinoculated with T. mentagrophytes var. granulosum and T. rubrum a study was carried out of the state of cellular immunity response, during infection, and also of the antigens responsible for the sensitization. Cellular immunity response was detected using the leucocyte migration test (L.M.T.) in the presence of antigenic compounds of the 'Keratinase' of Eleuterio et al.     

In Vitro Activity of Antifungal Drugs Against Trichophyton rubrum and Trichophyton mentagrophytes spp. by E-Test Method and Non-supplemented Mueller–Hinton Agar Plates

Mycopathologia - Trichophyton rubrum and Trichophyton mentagrophytes spp. are two of the most frequently isolated dermatophytes causing dermatophytosis worldwide. Since the incidence of resistance...     

Dermatophytes isolated in Hospital Universitario 12 de Octubre (Madrid, Spain).

Over a 10 year period (January 1988 - December 1997), 3,241 dermatophyte strains were isolated from 18,465 specimens from patients in whom dermatophytosis was suspected clinically. This represents a 17.5% rate of isolation. Trichophyton rubrum (38.44%), Microsporum canis (28.75%), Epidermophyton floccosum (14.5%) and Trichophyton mentagrophytes (13.5%) were the dominant species, and Trichophyton tonsurans (2.09%) has emerged, whilst in the previous decade it had virtually disappeared. Our study is basically based on an out-patient selected population, and tinea corporis (30.79%), followed by tinea cruris (16.69%) and tinea unguium (16.69%) were the most prevalent clinical forms.