**2. Short characteristic of dermatophytes**

There are many species of dermatophytes causing mycoses, so it is very important to assay them properly through mycological examination. Correct identification of the pathogen responsible for disease allows choosing a right treatment for patient.

Natural reservoir of dermatophytes is soil and keratin contained in soil is used as main nutrient for these fungi. However, evolutionary progress adapted these microorganisms to a various environments, so they generated ability to metabolize keratin derived not only from soil (Dworacka-Kaszak, 2004).

For that reason dermatophytes, with regard to their habitat, may be divided into antropophilic, zoophilic and geofilic species. For antrophophilic dermatophytes natural reservoir and carrier is human, zoophilic dermatophytes grow on domestic and stock animals and geophilic dermatophytes are found in soils (Adamski & Batura-Gabryel, 2007).

In laboratory practice dermatophyte fungi belonging to three genera (*Trichophyton*, *Microsporum*, *Epidermophyton*), are known. *Trichophyton* and *Microsporum* genera are the most numerous and diverse, there are over 40 species belonging to these two taxonomic groups. *Epidermophyton* genus has only one representative – *Epidermophyton floccosum* species.

The genera *Trichophyton* is numerous and diverse, for example, in the Lower Silesia region, in years 2003 – 2007, these fungi were isolated in 92% of all cultures (Jankowska-Konsur et al., 2011).

Epidemiology of Dermatomycoses in Poland over the Past Decades 33

 *Microsporum gypseum* – geophilic species, ubiquitous, isolated from soils worldwide. Most exposed to infections are people, who cultivate the soil (farmers, gardeners), percentage of males prevails over females. Sometimes infection could be transmitted from animals . In human it causes infections of the scalp (*tinea capitis*) and glabrous skin

 *Microsporum nanuum* – zoophilic species, isolated also from soil. It causes infections among breeding cattle, mostly in pigs. In human it causes infections of the glabrous skin (*tinea corporis*) and the scalp (*tinea capitis*) proceeding with or without severe

 *Microsporum persicolor* – zoophilic species, cosmopolitan. In human it causes infections of the scalp (*tinea capitis*), glabrous skin (*tinea corporis*) and feet (t*inea pedis*). Infections

The genera *Epidermophyton* has only one representative, quite often isolated form lesions:

 *Epidemophyton floccosum* – antropophilic species, cosmopolitan. In human it causes mostly infections of the groin (*tinea cruris*), rarely of glabrous skin (*tinea corporis*), feet

Dermatophytes are keratinophilic fungi, which parasitize on corneous structures, such as stratum corneum, hair or nails (Kobierzycka et al., 2005). Dermatophyte species are equipped with numerous enzymes, enabling them to survive on the skin and its appendages, because they have a proteolytic, keratinolytic and lipolytic activity. Furthermore the skin environment is conducive to dermatophytes because the corneal layer lacks blood vessels making it difficult to contact with immunologically competent cells and activate the defense mechanisms. On the surface of the epidermis are proteins, carbohydrates and micronutrients (including iron ions), which may provide substrates for the metabolism of fungi and help them to survive. Of great importance may also be some specific anatomic regions of the skin, greatly facilitating the colonization by fungi. Scalp hair can therefore arrest arthrospores spreaded by air. Similarly, spores are arrested in the hyponychium under or in the interdigital spaces, or in the folds of the skin where additionally oclusion helps them to develop (Dworacka-Kaszak, 2004). The spores are particularly resistant to environmental conditions, such as variable temperature and drying (Hryncewicz-Gwozdz et al., 2005; Kobierzycka et al., 2005). It is known that they can survive outside the host organism and colonize the skin and its appendages under favorable conditions, for example, in warm and humid environment, with increased amounts of CO2, which prevails in the poorly sheered shoes, it can lead to growth of the fungi and invasion of

To narrowly understand epidemiology of dermatomycoses, methods of pathogen

Infection with antropophilic dermatophytes may happen through direct contact with infected person, moreover spores of dermatophyte fungi can survive on skin and its

The sources of dermatophyte fungi infection are: human, animals and soil.

was isolated from fur of guinea pigs and rarely, from dog`s fur.

proceed with significant inflammatory reaction.

(*tinea pedis*) and very rarely of toenais (*onychomycosis)*.

**2.1 Methods of pathogen transmission – a short description** 

(*tinea corporis*).

inflammation.

the skin structures.

transmission, are described below.

caused by *Microsporum audouinii* also were described. Although it is human pathogen, it

In Poland, there are only few *Trichophyton* species, which are common, including:


Among *Microsporum* genera, only few species are common in lab-practice:


 *Trichophyton rubrum* – antropophilic dermatophyte, distributed worldwide, usually specific to human, but infections in animals also have been reported. It may be the cause of practically all infections of body surface areas (with exception of fungal infections of the scalp). Most commonly it causes onychomycosis and athlete`s foot (*tinea pedis*). It may also cause infections of glabrous skin (*tinea corporis*, *tinea faciei*), groin (*tinea cruris*), hands (*tinea manuum*) or nails (*tinea ungiuim*). This fungus causes

 *Trichophyton mentagrophytes* – zoophilic dermatophyte, cosmopolitan fungus, distributed worldwide. It causes infections in animals (cats, dogs, rabbits, guinea pigs, rodents, hedgehogs) as well as in human. Most commonly it causes infections of glabrous skin (*tinea corporis*, *tinea faciei*) and scalp infections (*tinea capitis*). Lesions often

 *Trichophyton tonsurans* – antropophilic species, usually specific to human, practically cosmopolitan. Most commonly it causes infections of the scalp (*tinea capitis*) and it may also cause infections of glabrous skin (*tinea corporis*), especially in the "shower area" on neck, shoulder, back, buttocks, and feet, when inoculum is washed off from head on the other parts of the body, while taking shower. Infections usually proceed with mild inflammatory reaction, but cases with severe inflammatory responses also have been reported. This fungus often causes family and school outbreaks. It is also responsible for infections among wrestlers and judo competitors (*tinea corporis gladiatorum*). This dermatophyte is resistant to the adverse impact of external conditions and it is

 *Trichophyton interdigitale* – antropophilic species, distributed worldwide. It causes infections of feet (aspecially in the interdigital spaces) and hands (*tinea manuum*),

 *Trichophyton verrucosum* – zoophilic species, the mostly isolated from cattle, it infects people, who work with these animals (farmers). Cosmopolitan fungus, it causes diseases of exposed parts of the body (*tinea corporis*) and face (*tinea faciei*), beard (*tinea* 

 *Trichophyton violaceum* – antropophilic species, mostly it causes infections of the scalp (*tinea capitis*) and glabrous skin (*tinea corporis*), aspecially in the "shower area". It can also cause onychomycosis. It is specific to human, but it also can be pathogenic for

*Trichophyton schoenleinii* – antropophilic species, it causes *favus*. Nowadays is practically

 *Microsporum canis* – zoophilic species, cosmopolitan, distributed worldwide. It is very contagious aspecially for young cats and dogs. In human it causes infections of the scalp (*tinea capitis*) and beard (*tinea barbae*) or infections of glabrous skin or face (*tinea* 

 *Microsporum audouinii* – antropophilic species, cosmopolitian, however, the incidence of fungal infections caused by this pathogen in Poland is very small. It causes infections of the scalp (*tinea capitis*), glabrous skin (*tinea corporis*), face (*tinea faciei*), affecting mostly school-age children (boys:girls=4:1), however cases of dermatomycoses in adults,

In Poland, there are only few *Trichophyton* species, which are common, including:

persistent, chronic infections.

proceed with a large inflammatory reactions.

transferred by asymptomatic carriers.

*barbae*) or head (*tinea capitis*).

unique.

*corporis*, *tinea faciei*).

sometimes it can also infect nails (*tinea unguium*).

animals. It is the cause of family and institutional outbreaks.

Among *Microsporum* genera, only few species are common in lab-practice:

caused by *Microsporum audouinii* also were described. Although it is human pathogen, it was isolated from fur of guinea pigs and rarely, from dog`s fur.


The genera *Epidermophyton* has only one representative, quite often isolated form lesions:

 *Epidemophyton floccosum* – antropophilic species, cosmopolitan. In human it causes mostly infections of the groin (*tinea cruris*), rarely of glabrous skin (*tinea corporis*), feet (*tinea pedis*) and very rarely of toenais (*onychomycosis)*.
