Images (6)
Trichophyton rubrum
HistoryThis section has been translated automatically.
DefinitionThis section has been translated automatically.
Anthropophilic dermatophyte.
Trichophyton rubrum is a skin fungus (anthropophilic dermatophyte) which colonises the horny substance in humans. It can cause numerous dermatophytoses in humans, and the pathogen is particularly common in the foot and nail fungus and the tinea inguinalis. Like all dermatophytes Trichophyton rubrum feeds on keratin. It is transmitted from person to person by direct or indirect contact. Transmission from humans to animals is also rare [1] Teleomorphism, i.e. the sexual stage of T. rubrum, is still unknown.
General definitionThis section has been translated automatically.
Occurrence/EpidemiologyThis section has been translated automatically.
Clinical pictureThis section has been translated automatically.
MicroscopyThis section has been translated automatically.
- In the native preparation, T. rubrum shows up in the form of a widely branched mycelium in case of skin diseases, and as spore chains in case of nail fungus.
- Long, thin hyphae, no spiral hyphae. Very rare occurrence of chlamydospores.
- Macroconidia: usually absent (exception: granular variants), long and smooth-walled, sausage- to cigar-shaped, strongly septated, rounded at the poles, length: 15-40 μm, width: 4-6 μm, 3-8 chambers.
- Microconidia: are very rare, unicellular, pear-shaped, acladium-shaped, arranged at the hyphae staggered (in acladium form), length: 3-5 μm, width: 2-3 μm.
DiagnosisThis section has been translated automatically.
Sabouraud dextrose agar: Formation of white, cotton wool-like, hat-shaped colonies with radial folding, which become greenish or red to violet in the fringe area; in woodlight diagnosis it shows no fluorescence. Underside of the culture wine-red.
Mycosel medium: Formation of an initially yellow, later red rim. Underside of the culture wine-red.
Creamy agar: cream-coloured culture with central raised area and broad, flat rim.
For a reliable differentiation of Trichophyton rubrum and Trichophyton interdigitale, special culture media (e.g. potato glucose agar or urea agar) may be additionally required for the detection of urea cleavage of Trichophyton interdigitale.
Note(s)This section has been translated automatically.
Known and analysed type I allergens in Trichophyton rubrum
- Tri r 2 Putative secreted alkaline protease Alp1
- Tri r 4 Serine protease
LiteratureThis section has been translated automatically.
- Ellis D (2000) Epidemiology: surveillance of fungal infections. Med Mycol 38: S173-182
- Kick G, Korting HC (2001) The definition of Trichophyton rubrum syndrome. Mycoses 44: 167-171
- Lacroix C (2002) Tinea pedis in European marathon runners. J Eur Acad Dermatol Venereol 16: 139-142
- Mungan D et al (2001) Trichophyton sensitivity in allergic and nonallergic asthma. Allergy 56: 558-562
- Seebacher C et al (2007) Onychomycosis. J Dtsch Dermatol Ges 5: 61-66
- Yazdanparast A et al (2003) Molecular strain typing of Trichophyton rubrum indicates multiple strain involvement in onychomycosis. Br J Dermatol 148: 51-54