Three years incidence of dermatophytes in a hospital in Porto (Portugal)

We evaluated the incidence of dermatophytes isolated at our hospital in the years of 1997 to 2000 and correlated it with anatomical site and age. Trichophyton rubrum was the predominant species in all anatomical sites, excluding scalp, followed by Microsporum canis, the leading agent of tinea capitis. All dermatophytosis, except tinea capitis by M. canis and Trichophyton schoenleinnii appeared mainly in adult patients. Our results revealed no substantial differences to other portuguese studies regarding the major agents. We found a relatively high incidence of T. schoenleinnii as second tinea capitis agent.     

Updates on the Epidemiology of Dermatophyte Infections

The spectrum of dermatophytes isolated from skin lesions had changed in last 70 years. Before the Second World War in Germany, Microsporum audouinii and Epidermophyton floccosum ranked the first, whereas Trichophyton rubrum is the most common dermatophyte since the fifties of last century, accounting for 80-90% of the strains, followed by T. mentagrophytes. This evolution is typical for Central and North Europe and it needs to be connected with the increase in the incidence of tinea pedis. In contrast, in Southern Europe and in Arabic countries, zoophilic dermatophytes, such as Microsporum canis or Trichophyton verrucosum, are the most frequently isolated. In Europe, especially in Mediterranean countries, the incidence of M. canis infection has strongly increased during the recent years and this dermatophyte is now the most prevalent in tinea capitis in children. An analysis of the frequency and distribution of tinea pedis in different occupations and leisure-time activities as well as the routes of infection are reported. The spreading of this disease in most developed countries of the world represents a considerable economic problem, since it was accompanied by a parallel increase in the frequency of onychomycosis which implies, as tinea pedis, large financial charges. In poor developing countries, mycoses appear endemically, primarily with children, and their treatment often fails because of the lack of efficient antifungals. The particular epidemiological situations of dermatophytoses and the pathogenic spectrum of dermatophytes are examined at the example of numerous countries.     

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.     

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.     

Molecular Typing Study of the Microsporum Canis Strains Isolated from an Outbreak of Tinea Capitis in School

Tinea capitis is a dermatophyte infection of the scalp that occurs most often in prepubescent children. Tinea capitis may be transmitted by shared use of contaminated hairbrush, by contact with fomites or by direct physical contact with an infected person. Occasionally, outbreak of tinea capitis would happen under some special conditions. Last year, we found an outbreak of tinea capitis in a school due to Microsporum canis. In epidemiological study, we performed the prevalence survey to all of the exposed persons by physical examinations and mycological laboratory tests, including KOH preparation and fungal cultures. We also investigated the environment in the school. In molecular typing study of the M. canis isolated from patients and the environment, random primer amplification polymorphic DNA (RAPD) method, the specific amplification of subrepeat element in the ribosomal DNA nontranscribed spacer (NTS), and the analysis of DNA sequence in the intertranscribed spacer (ITS) of rDNA were performed. The total number of exposed children was seventy-one, among them forty-two were attacked by tinea capitis. The ratio between boy and girl was 13:1. The ages of the patients was ranged from 3.5 years old to 10 years old. Four patients bred cat or dog as pet. Most patients appeared noninflammatory type of tinea capitis and several patients were inflammatory type. Under microscopic examination the invaded hair were all ectothrix. The pathogens isolated from these patients were M. canis. And we also isolated M. canis from the carpet and the pillowcase in the school. The patterns of total strains of M. canis in the RAPD method and PCR amplification of the rDNA NTS region study were identical, and the isolates from patients and the environment contained the same DNA sequences in the ITS region. The outbreak of tinea capitis was caused by M. canis. The M. canis isolated from patients and from the environment were probably the same origin.     

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。     

Phenotypical and molecular characterization of Microsporum canis strains in north-east Brazil

AIMS: This study investigated the possible correlation between the phenotypical and genotypical characteristics of Microsporum canis isolated from cats and dogs in north-east Brazil. METHODS AND RESULTS: The mycological study was conducted by direct microscopic examination and by fungal culture. Polymerase chain reaction-restriction enzyme analysis and random amplification of polymorphic DNA techniques were used for the genotypical analysis. The morphological analysis showed a considerable diversity of colonies as well as different morphologies of conidia, despite the M. canis strains having been isolated under the same conditions. However, the molecular analysis showed that all analysed strains are genetically similar. CONCLUSIONS: This study, based on phenotypical and molecular analysis, evidences the wide spectrum of phenotypical variations in M. canis in contrast to the stable genotypes of such dermatophytes. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this study indicate that M. canis isolated from cats and dogs with dermatophytosis in north-east Brazil may be clones, well adapted to the conditions of this region, despite M. canis showing different morphological features.     

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.     

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.     

Extracellular proteolytic activity and molecular analysis of Microsporum canis strains isolated from symptomatic and asymptomatic cats

Microsporum canis is the main zoophylic dermatophyte in dogs and cats, and it is also an important zoonotic agent. The literature showed that cats are asymptomatic carriers of M. canis. This is apparently due to host resistance and/or the presence of strains with lower virulence. This study was aimed to evaluate the keratinolytic, elastinolytic and collagenolytic activities of M. canis strains and their relationship with symptomatic and asymptomatic cats. In addition, these strains were analysed by RFLP. The strains isolated from cats with clinical dermatophytosis had higher keratinase and elastase activity than those isolated from asymptomatic animals (p minus than 0.05). There were not differences in RFLP patterns based on Hind III digestion.     

Enigmatic relationship of two Microsporum species

Unusual cultures of a Microsporum species were isolated from eleven patients who had either tinea capitis or tinea corporis or both. Although the macroconidia produced in the primary cultures resembled those of M. canis, hyphal morphology and colony characteristics were different from any of the more commonly occurring Microsporum species. Careful examination of subcultures showed that the isolates were composed of two species; M. canis and M. distortum, whose relationship remains enigmatic.     

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.     

Antifungal susceptibility and genotypical pattern of Microsporum canis strains

Dermatophytes are a group of fungi that are capable of invading keratinized tissues of humans and other animals. Antifungal susceptibility analysis and genetic studies by random amplification of polymorphic DNA (RAPD), have been used to detect polymorphism as well as determining the possible resistance of dermatophytes to antifungals. The aim of this study was to evaluate the possible correlation between the antifungal susceptibility and genotypical pattern of Microsporum canis strains isolated in dogs and cats with dermatophytosis in Northeast Brazil. The antifungal susceptibility study was conducted using the broth microdilution test with griseofulvine, ketoconazole, itraconazole, and fluconazole. The genotypical analysis was performed using the RAPD method. The antifungal susceptibility analysis showed that all the strains of M. canis analyzed (n = 22) were sensitive to griseofulvine (0.25 microg/mL < or minimum inhibitory concentration (MIC) < or = 1 microg/mL), ketoconazole (0.25 microg/mL < or = MIC < or = 2 microg/mL), itraconazole (0.25 microg/mL < or = MIC < or = 1 microg/mL), and fluconazole (1 microg/mL < or = MIC < or = 16 microg/mL). The RAPD results showed that all analyzed strains are genetically similar. Thus, based on antifungal susceptibility analysis and RAPD data, a possible correlation can be shown between the antifungal susceptibility and the genotypical pattern of the strains of M. canis from Northeast Brazil.     

13 Years of veterinary mycological routine diagnostics. Isolation of dermatophytes in the years 1965-1977

Over a thirteen year period (1965 to 1977) a total of 4790 skin scrapings and hair samples of animals were examined mycologically. 887 strains of dermatophytes were isolated out of 885 of these samples (= 18,5%). Most frequently Trichophyton verrucosum was identified in samples from cattle, followed by Microsporum canis isolated from cats, dogs and zoo animals. T. mentagrophytes was mainly found on guinea pigs, chinchillas and dogs and T. equinum on horses. Although the total number of the samples examined within the last 8 years increased, the total of the dermatophytes isolated remained proportionately the same. The relative numbers of the various species of dermatophytes isolated did not change within the period of investigation.     

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.     

High rate of Microsporum canis feline and canine dermatophytoses in Northeast Brazil: Epidemiological and diagnostic features

Over a one year period (November 2000-December 2001), clinical specimens from 189 dogs and 38 cats, from the city of Fortaleza, Ceará, Brazil, were examined at the Specialized Medical Mycology Center at the Federal University of Ceará to detect animals with dermatophytoses. The mycological analyses were conducted by direct microscopy and by fungal culture on Sabouraud agar, Sabouraud chloramphenicol agar and Mycosel agar. Dermatophytes were isolated from 27 of the 189 (14.3%) canine specimens and 14 of the 38 (36.8%) feline specimens. The identified dermatophytes were Microsporum canis (95%), M. gypseum (2.5%) and Trichophyton mentagrophytes var. mentagrophytes (2.5%). Microsporum canis was the most common species isolated (92.6% and 100%, for dogs and cats respectively). The percentage of positive direct microscopic examinations of clinical specimens and positive cultures was 61%. There was a high proportion of positive cultures from cats less than 1 year of age, but in dogs no significant differences were detected. There were no significant differences between the sexes. Dermatophytes were more frequently isolated in March, April and May, but no significant differences were detected in the seasonal distribution of canine and feline dermatophytoses.     

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。     

Analytical isoelectric focusing of secreted dermatophyte proteins applied to taxonomic differentiation of Microsporum and Trichophyton species (preliminary studies)

Culture filtrates were prepared from dermatophytes under standard conditions and adapted for analytical isoelectric focusing in thin layer polyacrylamide gels over the pH range 3.5-9.5. Dermatophytes grown in trypticase soy broth secreted a large number of proteins displaying a wide range of isoelectric points (pIs). Trichophyton megninii extracts contained a triplet of proteins focusing in the pH 8.0-8.5 range that were absent in taxonomically related T. kuryangei isolates. Single ascospore isolates and standard tester strains of Nannizzia otae (+) mating type were differentiated from the (-) mating type by proteins focusing at pH 6.5 and 8.4. These were markedly reduced in the (+) type. The isofocused pattern of Microsporum canis conformed closely to the (-) mating type of N. otae. The protein patterns of T. megninii and T. kuryangei were distinct from those obtained with M. canis and M. equinum because of an intense-staining broad protein band, pI 7.2, and three periodic acid-Schiff-positive glycoproteins focusing in the acidic range which were absent in the Microsporum species. A characteristic protein or doublet (pI 8.7) was present in the Microsporum species and absent in the Trichophyton species. Analytical isoelectric focusing is a potentially useful method to distinguish inter- and intra-species differences in the pattern of secreted dermatophyte proteins present in culture filtrates and in trichophytins. The information derived may be useful in the classification of species.     

Characterization of rabbit Pasteurella multocida isolates by use of whole-cell, outer-membrane, and polymerase chain reaction typing.

PURPOSE: To characterize Pasteurella multocida isolates from laboratory rabbits using serotyping, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins (WCPs) and outer-membrane proteins (OMPs), and polymerase chain reaction (PCR) fingerprinting. METHODS: Fifty isolates were obtained from five sources: ATCC (1), Oklahoma (4), Michigan (9), Minnesota (7), and Texas (29). The PCR fingerprinting was conducted using two minisatellite probes for M13 and a modified M13 core sequence and two microsatellite probes--(GTG)5 and (GACA)4. RESULTS: Forty-five isolates were serogroup A, and five were serogroup D. Ten WCP patterns (W1-W10) with one variation (W1a) and 10 OMP (OM1-OM10) patterns were found. Primers M13 phage, modified M13 phage, (GTG)5, and (GACA)4 generated 7, 9, 5, and 9 fingerprint types, respectively. Combination of WCP, OMP, and PCR fingerprint results yielded 39 groups with a discrimination index of 0.98. The PCR fingerprint results generally indicated clonal association among isolates within geographic locations except for the isolates from Texas, which varied markedly in PCR fingerprint types. CONCLUSION: Single primer PCR fingerprinting provided a simple and rapid means of typing P. multocida isolates from laboratory rabbits. Combinations of conventional and molecular typing enhanced differentiation among P. multocida isolated from rabbits with pasteurellosis.     

杭州部分地区头癣73例类型及病原菌分析

目的 了解近2年来杭州部分地区头癣类型及其病原菌分布情况。方法 采用回顾性方法对2003年5月～2005年4月在杭州市第三人民医院皮肤科门诊诊治的头癣患者进行分析。结果 73例头癣患者中白癣41例（56．16％）、黑癣23例（31．5％）、脓癣9例（12．33％）,未发现黄癣。51例行真菌培养。主要病原菌为犬小孢子菌22例（43．14％）、紫色毛癣菌17例（33．33％）、须癣毛癣菌8例（15．69％）、断发毛癣菌4例（7．84％）。结论 杭州地区头癣患者中白癣发病率占首位,犬小孢子菌为主要致病菌。