Trichophyton mentagrophytes belongs to the dermatophytes, fungi that mainly infect the skin, but also skin appendages such as nails and hair. In addition, there are about 20 other species of trichophytes. The diseases caused by the dermatophytes are called dermatomycoses or tinea.
What is trichophyton mentagrophytes?
Trichophyton mentagrophytes is a hyphal fungus or filamentous fungus. These are so named because they form thread-like cells called hyphae. The so-called mycoses are the corresponding diseases. Trichophyton mentagrophytes is also one of the parasites. These infest a host and damage it in order to gain energy from it. Tinea, which refers to the disease caused by Trichophyton mentagrophytes, has a variety of manifestations, mainly affecting the skin. The skin is usually reddened and secretes numerous scales, which can be infectious. Tinea can occur anywhere and spread from point to point. In this case, the fungus usually remains only on the most superficial layers of the skin, only rarely does it spread into deeper layers to the subcutaneous fatty tissue. Trichophyton mentagrophytes is transmitted, on the one hand, through contact from various people, but it can also be transmitted through contact with animals or even the earth.
Occurrence, distribution, and characteristics
Trichophyton mentagrophytes is found almost all over the world. It prefers thereby above all damp and warm places, like the other Dermatophytes also. In humans, these are mainly located between the toes and in sweaty skin folds. In addition, the fungus can also spread in nails or hair. Most important is the presence of horny substance or other keratin-containing tissues, which is the main food source of Trichophyton mentagrophytes. In addition, Trichophyton mentagrophytes primarily colonizes rodents and camels and is increasingly found on the fur of these animals. Accordingly, the spread of Trichophyton mentagrophytes is primarily zoophilic, that is, from animals to humans. However, transmission between humans who are in close contact is also possible. This is called anthropophilic transmission. Thus, the risk of infection is particularly high in communal showers, swimming pools and saunas. In addition to transmission through animals and humans, contact with contaminated soil can also pose a risk. People who frequently work in the garden are most frequently affected by infection. Structurally, Trichophyton mentagrophytes belongs to the filamentous or hyphal fungi. In order for these to grow, they obtain their energy from keratin, which they obtain from the skin, hair or nails. A certain enzyme, keratinase, helps them to extract the keratin from these tissues and use it for their own purposes. To further penetrate the skin, Trichophyton mentagrophytes also has elastases, proteinases and collagenases. To diagnose the fungus, its structure must be analyzed. This can be viewed under the microscope. For this purpose, some affected skin areas are taken and dissolved in a KOH solution, which can be applied to a microscope slide. Microscopically, conidia can be viewed. These are the asexual spores that occur as a spin-off in Trichophyton. Trichophyton mentagrophytes has predominantly microconidia. The macroconidia are rather rarely observed. The fungus can also form spores that can persist for a long time and are extremely stable, these are also infectious to humans for a long time. If the fungus is cultivated, one recognizes a fast growth with a yellowish-white and downy surface. In the case of Trichophyton mentagrophytes, an anamorphic form (asexual form), as well as a teleomorphic form (sexual form) are known. The teleomorphic form belongs to the so-called Arthoderma simii complex.
Diseases and medical conditions
Dermatomycosis or tinea is the typical disease pattern of a Trichophyton mentagrophytes. These are diseases with fungi that primarily affect the skin, as well as its skin appendages, i.e. hair and nails. Tinea is usually characterized by a reddening of the skin, which can scaly strongly. This skin area can spread further outwards and affect neighboring skin areas. However, mycosis can also have different appearances.In the nail, Trichophyton mentagrophytes can cause a nail fungus (tinea unguium). In this case, the nail turns brownish and has a high risk of breaking. However, Trichophyton mentagrophytes most frequently attacks the head area (tinea capitis) and the body (tinea corporis). In this case, the fungus usually appears in the form of a favus, which means that the fungus spreads deep into the hair follicles and thus damages the hair. The hair becomes brittle and tends to break strongly. Tinea barbae, which is a fungal infestation in the beard area, is also mainly caused by Trichophyton mentagrophytes. In some, severe cases, it can also lead to the formation of a kerion, when the skin becomes inflamed and a lump forms.
