''Trichophyton'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...
, which includes the
parasitic
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...
varieties that cause
tinea
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple ar ...
, including
athlete's foot
Athlete's foot, known medically as ''tinea pedis'', is a common skin infection of the feet caused by a fungus. Signs and symptoms often include itching, scaling, cracking and redness. In rare cases the skin may blister. Athlete's foot fungus m ...
,
ringworm
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple a ...
,
jock itch
Jock may refer to:
Common meanings
* Jock (stereotype), a North American term for a stereotypical male athlete
* Jock, a derogatory term for Scottish people mostly used by the English
* Short for jockstrap, an item of male protective undergarmen ...
, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are
mold
A mold () or mould () is one of the structures certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal seco ...
s characterized by the development of both smooth-walled macro- and
microconidia
A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to th ...
.
Macroconidia
A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an Asexual reproduction, asexual, non-motility, motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are al ...
are mostly borne laterally directly on the hyphae or on short pedicels, and are thin- or thick-walled,
clavate
This glossary of entomology describes terms used in the formal study of insect species by entomologists.
A–C
A synthetic chlorinated hydrocarbon insecticide, toxic to vertebrates. Though i ...
to
fusiform
Fusiform means having a spindle-like shape that is wide in the middle and tapers at both ends. It is similar to the lemon-shape, but often implies a focal broadening of a structure that continues from one or both ends, such as an aneurysm on a b ...
, and range from 4 to 8 by 8 to 50
μm in size. Macroconidia are few or absent in many species. Microconidia are spherical, pyriform to clavate or of irregular shape, and range from 2 to 3 by 2 to 4 μm in size.
Species and their habitat preference
According to current classification, the genus includes anthropophilic and zoophilic species.
[ ]Anthropophilic
In parasitology, anthropophilia, from the Greek ἅνθρωπος (anthrōpos, "human being") and φιλία (philia, "friendship" or "love"), is a preference of a parasite or dermatophyte for humans over other animals.Braun-Falco, Otto (2000). ...
fungi prefer to infect humans. Zoophilic
Zoophily, or zoogamy, is a form of pollination whereby pollen is transferred by animals, usually by invertebrates but in some cases vertebrates, particularly birds and bats, but also by other animals. Zoophilous species frequently have evolved ...
fungi prefer to infect animals other than humans. Humans and animals are natural reservoir
In infectious disease ecology and epidemiology, a natural reservoir, also known as a disease reservoir or a reservoir of infection, is the population of organisms or the specific environment in which an infectious pathogen naturally lives and rep ...
s for parasitic or dermatophytic fungi.
Other accepted species;
* '' Trichophyton ajelloi''
* '' Trichophyton areolatum''
* '' Trichophyton balcaneum''
* '' Trichophyton batonrougei''
* '' Trichophyton brumptii''
* '' Trichophyton candelabrum''
* '' Trichophyton cerebriforme''
* '' Trichophyton circonvolutum''
* '' Trichophyton denticulatum''
* ''Trichophyton depressum
''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are Mold (fungus), molds ...
''
* '' Trichophyton farinulentum''
* '' Trichophyton fischeri''
* '' Trichophyton flavescens''
* '' Trichophyton floriforme''
* '' Trichophyton fluviomuniense''
* '' Trichophyton fuligineum''
* '' Trichophyton glabrum''
* '' Trichophyton gloriae''
* '' Trichophyton gourvilii''
* '' Trichophyton guzzonii''
* '' Trichophyton immergens''
* '' Trichophyton indicum''
* '' Trichophyton kanei''
* '' Trichophyton krajdenii''
* '' Trichophyton kuryangei''
* '' Trichophyton longifusum''
* '' Trichophyton louisianicum''
* '' Trichophyton mariatii''
* ''Trichophyton megninii
''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterized ...
''
* '' Trichophyton milochevitchii''
* '' Trichophyton multicolor''
* '' Trichophyton oceanicum''
* '' Trichophyton ochoterenai''
* '' Trichophyton olexae''
* '' Trichophyton pedis''
* '' Trichophyton plurizoniforme''
* '' Trichophyton pratense''
* '' Trichophyton proliferans''
* '' Trichophyton pseudotonsurans''
* '' Trichophyton purpureum''
* '' Trichophyton radicosum''
* '' Trichophyton raubitschekii''
* '' Trichophyton rotundum''
* '' Trichophyton sabouraudii''
* '' Trichophyton sarkisovii''
* ''Trichophyton spadix
''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are Mold (fungus), molds ...
''
* '' Trichophyton teheraniense''
* '' Trichophyton tenuishyphum''
* ''Trichophyton vanbreuseghemii
''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are Mold (fungus), molds ...
''
Mating and meiosis
''Trichophyton mentagrophytes'' (Family Arthrodermataceae, Genus Trichophyton) is capable of both mating
In biology, mating is the pairing of either opposite-sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. ''Copulation'' is the union of the sex organs of two sexually reproduc ...
and meiosis
Meiosis (; , since it is a reductional division) is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately resu ...
.
Effect on humans
The anthropophilic
In parasitology, anthropophilia, from the Greek ἅνθρωπος (anthrōpos, "human being") and φιλία (philia, "friendship" or "love"), is a preference of a parasite or dermatophyte for humans over other animals.Braun-Falco, Otto (2000). ...
varieties cause forms of dermatophytosis
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple ar ...
, that is, fungal infection of the skin. They are keratinophilic: they feed on the keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...
in nails, hair, and dead skin.
''Trichophyton concentricum'' causes "Malabar itch", a skin infection consisting of an eruption of a number of concentric rings of overlapping scales forming papulosquamous
A papulosquamous disorder is a condition which presents with both papules and scales, or both scaly papules and plaques.
Examples include psoriasis, lichen planus, and pityriasis rosea
Pityriasis rosea is a type of skin rash. Classically, it be ...
patches.
''Trichophyton rubrum'' and ''Trichophyton interdigitale'' cause athlete's foot (tinea pedis), toenail fungal infections (a.k.a. tinea unguium, a.k.a. onychomycosis), crotch itch (a.k.a. tinea cruris), and ringworm
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple a ...
(a misnomer, as there is no worm involved; it is also known as tinea corporis). ''Trichophyton schoenleinii'' cause favus (tinea capitis),''Trichophyton mentagrophytes var. mentagrophytes'' and ''Trichophyton verrucosum'' cause kerion
Kerion or kerion celsi is an acute inflammatory process which is the result of the host's response to a fungal ringworm infection of the hair follicles of the scalp (occasionally the beard) that can be accompanied by secondary bacterial infection( ...
(violent reaction results from infection with an animal dermatophytes). Fungal folliculitis is a rare hair follicle infection induced overwhelmingly by ''Trichophyton'', which can be spread zoonotic
A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a bacterium, virus, parasite or prion) that has jumped from a non-human (usually a vertebrate) to a human. ...
ally. The fungi can easily spread to other areas of the body as well and to the host's home environs (socks, shoes, clothes, showers, bathtubs, counters, floors, carpets, etc.).
They can be transmitted by direct contact, by contact with infested particles (of dead skin, nails, hair) shed by the host, and by contact with the fungi's spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...
s. These fungi thrive in warm moist dark environments, such as in the dead upper layers of skin between the toes of a sweaty foot inside a tightly enclosed shoe, or in dead skin particles on the wet floor of a communal (shared) shower. Their spores are extremely difficult to eliminate, and spread everywhere.
When the hyphae
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium.
Structure
A hypha consists of one or ...
of the fungi burrow into the skin and release enzymes to digest keratin, they may irritate nerve endings and cause the host to itch
Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasant ...
, which may elicit the scratch reflex
The scratch reflex is a response to activation of sensory neurons whose peripheral terminals are located on the surface of the body.Stein, P. S. G. (1983). The vertebrate scratch reflex. Symposia of the Society for Experimental Biology(37), 383 ...
, which directs the host to scratch. Scratching directly transfers fungi and dead skin particles that are infested with the fungi to the fingers and under the finger nails. From there they can be transmitted to other parts of the host's body when the host touches or scratches those. Scratching also damages skin layers, making it easier for the fungi to spread at the site of the infection. If the fungi and infested debris are not washed from the fingers and fingernails soon enough, the fungi can also infect the skin of the fingers (tinea manuum
Tinea manuum is a fungal infection of the hand, mostly a type of dermatophytosis, often part of two feet-one hand syndrome. There is diffuse scaling on the palms or back of usually one hand and the palmer creases appear more prominent. When both ...
), and burrow underneath and into the material of the fingernails (tinea unguium
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple a ...
). If left untreated, the fungi continue to grow and spread.
Treatments
A variety of zoophilic and anthropophilic dermatophyte treatments have varying levels of success based on species type. Treatments may take up to six months.
References
External links
Doctor Fungus
Mycology Unit at the Adelaide Women's and Children's Hospital
{{Taxonbar, from=Q310925
Parasitic fungi
Arthrodermataceae
Cat diseases
Eurotiomycetes genera