Dermatophyte
As dermatophytes ( from Ancient Greek τὸ δέρμα, to derma "skin" and τὸ φυτόν, to phyton "the plant") are filamentous fungi called (Hyphomycetes) having a specific fungal infection of the skin that Dermatophytosis trigger. In contrast to other skin fungi , dermatophytes feed on carbohydrates and keratin . You can break down keratin using the enzyme keratinase .
Classification and characteristics
At present, 38 types of pathogenic dermatophytes are known in humans and animals . They belong to three genera within the Moniliaceae and Arthrodermataceae families :
The following table shows the most important human pathogens:
| Pathogen | Culture (macroscopic) | Culture (microscopic) | host | comment |
|---|---|---|---|---|
| Trichophyton rubrum | Surface: white, velvety. Back: reddish pigment at the edge |
Mi : numerous, pear-shaped, arranged like a spike Ma : rare, cigar-shaped, 3–8 chambers Ch : very rare |
anthropophilic | Most common dermatophyte pathogenic to humans |
| Trichophyton interdigitale | Surface: white, powdery, aerial mycelium, reverse side: slightly brownish |
Mi : arranged in the shape of spikes and grapes. Ma : short, cigar-shaped, 3–5 chambers. Hy : spiral hyphae very common, branching hyphae in the shape of a candle holder |
anthropophilic | Differentiation from T. rubrum on special agar ( urease agar ) possible |
| Trichophyton mentagrophytes | Surface: white, plaster-like, flat. Back: slightly brownish |
like T. interdigitale | zoophilic (e.g. rodents) | |
| Trichophyton terrestre | Surface: white, cotton-wool, rapidly growing. Back: almost completely white |
Mi : pear-shaped, arranged in the form of ears Ma : multi-chambered, elongated, tapering to a point at the poles Hy : spiral hyphae also intermediate between micro- and macroconidia |
geophile | Culture has a typical “spicy” smell |
| Trichophyton tonsurans | Surface: flat colonies, white, recessed center. Reverse: light yellow to sulfur yellow |
Mi : elongated, stalked on the hyphae Ma : rare, elongated, thin-walled Ch : frequent, often on the ends of hyphae ("Raquet hyphae") |
anthropophilic | Typical pathogen of "ringworm" ( Tinea corporis gladiatorum ) |
| Microsporum canis | Surface: flat, ray-like colonies, first white, then orange-yellow. Back: yellowish |
Mi : acladium-shaped along the hyphae Ma : spindle-shaped, thick-walled, 3–18 chambers Ch : rare |
zoophile (more cats than dogs) | The world's most common zoophilic dermatophyte, high contagiousness, can also be transmitted from person to person |
| Microsporum gypseum | Surface: fast-growing, powdery-gypsum-like, slightly ocher-colored colonies. Reverse side: dark brown |
Mi : seldom, pear-shaped. Ma : frequent, plump, rounded, 4–6 chambers |
geophile | spread all over the world, earlier often gardener microsporia |
| Epidermophyton floccosum | Surface: very firm, yellowish-brownish colonies. Reverse: yellowish-brownish |
Mi : completely absent Ma : club-shaped, several standing on the end of the hyphae (“ADIDAS-form”) Ch : many, both intercalary and terminal |
anthropophilic | Due to the firmness of the colonies, it is not possible to copy the adhesive tape, only to be removed with a hook is the only human pathogenic dermatophyte that cannot infect hair |
| Trichophyton verrucosum | Surface: very slowly growing, cartilaginous-cerebriform, greyish-yellowish colonies. Reverse side: cream-colored |
Mi : rarely, can often only be detected after adding thiamine and inositol to the agar Ma : extremely rare, small, 3–5 chambers Ch : terminally arranged Hy : strongly branched |
zoophile (often cattle) | belongs to the faviform dermatophytes, vaccination possible in cattle |
| Trichophyton schoenleinii | Surface: velvety, creamy white, back: white to light brown |
Wed : only sporadically, after adding vitamins (see T. verrucosum) Ma : very rarely Ch : more often than with T. verrucosum Hy : strongly branched |
anthropophilic | classic pathogen of favus (" Erbgrind "), characteristic odor ("mouse urine") |
| Trichophyton violaceum | Surface: violet, velvety, aerial mycelium, reverse side: violet |
Mi : very seldom Ma : very seldom Ch : frequent, terminal and intercalated Hy : branched, compressed at the branches |
anthropophilic | mainly found in / in the Mediterranean / Africa / Latin America |
| Trichophyton soudanense | Surface: slowly growing, flat, radiating colonies, apricot-colored. Back: yellow to carrot-red |
Mi : rarely Ma : absent Ch : often, sometimes arranged in chains Hy : growing forwards and backwards |
anthropophilic | previously only in the tropics , now worldwide |
| Trichophyton equinum | Surface: rapidly growing, flat colonies with cotton wool aerial mycelium, whitish, yellowish at the edge. Reverse : yellowish brown |
Mi : teardrop-shaped Ma : very rare, thin and elongated |
zoophile (especially horses) | is rarely transmitted to humans |
| Microsporum audouinii | Surface: slowly growing, matt-velvety, brown-yellowish colonies. Reverse: pink to orange-brown |
Mi : pear-shaped Ma : relatively rare, 7–9 chambers, spindle-shaped, often also irregular Ch : numerous, terminally positioned Hy : "comb hyphae" |
anthropophilic | formerly known as “defaced by children's heads”, it was only found in Africa for a long time. However, it reappeared in Germany, e.g. in Munich (2011) or Bonn (2015) |
( Mi = microconidia, Ma = macroconidia, Ch = chlamydospores, Hy = hyphae)
Most common pathogens in animals:
| host | Common pathogens |
|---|---|
| Domestic cat | Microsporum canis (98%), rarely: Trichophyton mentagrophytes , Microsporum gypseum |
| Domestic dog | Microsporum canis , Trichophyton mentagrophytes |
| Domestic rabbit | Trichophyton tonsurans , Trichophyton mentagrophytes , rarely: Microsporum canis |
| House guinea pigs | Trichophyton mentagrophytes , rarely: Microsporum ssp. |
| Domestic cattle | Trichophyton verrucosum |
| Domestic horse | Microsporum canis , Microsporum equinum , Microsporum gypseum , Trichophyton equinum , more rarely: Trichophyton verrucosum , Trichophyton mentagrophytes , Trichophyton quinckeanum |
| Golden hamster | Trichophyton mentagrophytes , rarely: Microsporum ssp. |
| House mouse | Trichophyton mentagrophytes |
| Gerbil | Microsporum gypseum , Microsporum audouinii , more rarely Trichophyton mentagrophytes , Trichophyton verrucosum , Trichophyton rubrum , Trichophyton schönleinii |
| chinchilla | Trichophyton mentagrophytes , rarely: Microsporum ssp. |
| Ferrets | Microsporum canis |
| Hedgehog | Trichophyton mentagrophytes , Trichophyton schönleinii , Trichophyton erinacei , Microsporum cookei |
| Birds | Trichophyton gallinae |
| Turtles | Trichophyton seinelii |
literature
- Michael Rolle, Anton Mayr: Medical microbiology, infection and disease theory . 7th edition. Enke-Verlag, 2007, ISBN 3-8304-1060-3 .
Individual evidence
- ↑ Y. Gräser, M. El Fari u. a .: Phylogeny and taxonomy of the family Arthrodermataceae (dermatophytes) using sequence analysis of the ribosomal ITS region. In: Medical mycology. Volume 37, Number 2, April 1999, pp. 105-114, PMID 10361266 .
- ↑ after H.-J. Tietz, H. Ulbricht: Human pathogenic fungi of the skin and mucous membranes . Schlütersche, Hannover 1999, ISBN 3-87706-540-6 .
- ^ P. Fritsch: Fungal diseases (mycoses) . In: Dermatology and Venereology. Textbook and atlas . Springer-Verlag, Berlin / Heidelberg 1998, ISBN 3-540-61169-X , pp. 282-302.
- ↑ Is the head fungus returning? Report in the Ärztezeitung (online) from December 8, 2011
- ↑ Archive link ( Memento of the original from November 10, 2015 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. .
- ↑ P. Hensel: The feline dermatophytosis - diagnosis and therapy . In: Kleintiermedizin , (5/6) / 2006, pp. 122–132
- ↑ Ch. Noli, F. Scarampella: Dermatophytosis . In: Practical Dermatology in Dogs and Cats . Schlütersche, Hannover 2004, ISBN 3-87706-726-3 , pp. 203-210.
- ↑ a b c d e f g h i K. Gabrisch, P. Zwart: Diseases of domestic animals . 6th edition Schlütersche, Hannover 2005, ISBN 3-89993-010-X .
- ↑ M. Schäfer, O. Dietz, A. Weber: Skin diseases . In: O. Dietz, B. Huskamp (Hrsg.): Handbuch der Pferdepraxis . 2nd edition. Enke Verlag, Stuttgart 1999, ISBN 3-432-29262-7 , pp. 223-266.
- ↑ M. Rolle (ed.): Hypomyecetes or Fadenpilze . In: Rolle, Mayr: Medical microbiology, infection and disease theory . 6th edition. Enke Verlag, Stuttgart 1993, ISBN 3-432-84686-X , pp. 826-836.
