Dermatomycosis
| Classification according to ICD-10 | |
|---|---|
| B36.9 | Superficial mycosis, unspecified |
| ICD-10 online (WHO version 2019) | |
A Dermatomykose (from Greek δέρμα Derma , German , skin ' , and ancient Greek μύκης , Mykes , "mushroom" and ending with ose ) is one of on the skin growing human and animal fungal disease caused. The most common are fungal skin diseases that affect the horny substance , they are called dermatophytoses . In addition, there are fungal diseases that also affect deeper layers of the skin. In a broader sense, diseases caused by yeasts or molds , which are opportunistic pathogens, are also included.
Symptoms
Fungal skin disease manifests itself in itchy, slightly reddened and flaky areas of the skin as well as oozing blistering. Despite the sometimes severe itching , you should avoid scratching yourself. This not only increases the risk of spreading the disease via the fingers to other areas of the body, but also enables the fungus to penetrate deeper layers of skin through small wounds and cracks in the skin. In addition, secondary infections with bacteria can occur, which can negatively affect the chances of healing.
Development factors
The balance between the aggressiveness of the fungus and the immune system of the infected host is decisive for the development of dermatomycoses . There are types of fungus that always infest healthy tissue (for example Histoplasma capsulatum ), but if the immune system is “good”, further spread is limited. Poor hygiene, especially a lack of regular cleaning of the base of the toes and in the area between the feet, promotes the development of athlete's foot , but is often not the trigger. Excessive washing, in turn, especially with soap-based agents, destroys the protective acid mantle of the skin and thus hinders the normal defense system.
The internal ( endogenous ) functional condition of the affected area and the condition of the entire host are also important . In the case of injuries, impaired blood circulation or other pathological changes, so-called secondary mycoses can develop. Such a fungal disease does not occur in healthy conditions, the fungal species involved are therefore only possibly pathogenic (facultative pathogenic ).
External ( exogenous ) factors are also extremely important : Fungi multiply in a warm and humid environment. Mycoses of the feet are also favored by the excessive sweating of the feet, which is also referred to as sweaty feet .
Classification
The medically relevant skin fungi are divided into three groups (DHS system):
-
Dermatophytes (thread fungi)
- Epidermophyton - this fungus spreads on the cornea , it is known as athlete's foot.
- Microsporum canis - leads to circular hair loss with flaky skin and hair stumps that remain as black points.
- Trichophyton - spreads in the cornea, the hair follicles and into the surrounding connective tissue. Is accompanied by the formation of abscesses . All stages from superficial to deeper layers of the skin are possible, mostly circular or garland-shaped skin involvement. The lifespan of the spores outside the body is several months. Trichophyton is the most common thread fungus in Europe. The fungus can spread to the nails (" nail fungus ").
- Yeasts - spread on the skin, the mucous membranes, but also infestation of all internal organs up to severe sepsis , for example Candida albicans , known as thrush disease with whitish coatings on the oral mucous membrane. A facultative pathogenic yeast is Malassezia furfur .
- Medically relevant molds - can feed on both dead and healthy tissue, and are therefore able to act as pathogens, for example when the immune system is weakened.
diagnosis
The diagnosis of dermatophytoses has been difficult and time-consuming up to now. None of the detection methods alone provided reliable results. The molecular detection of pathogen-specific gene segments opens up the possibility of safe and reliable diagnostics in the event of suspected dermatophytosis. The combination of different methods was imperative, the “gold standard” is still the combination of direct detection and fungal culture.
Molecular Diagnostics
The immediate molecular diagnosis of dermatophytes made from native material from patients with suspected dermatomycosis using the polymerase chain reaction (PCR) is becoming increasingly important. The PCR duplicates pathogen-specific DNA sequences that are located in so-called marker gene areas of the respective dermatomycosis pathogens and allow a species-specific differentiation. The detection takes place z. B. by means of agarose gel electrophoresis with subsequent gel documentation . An easily manageable, routine and safe diagnosis of the most important dermatomycosis pathogens within a few hours is thus possible. The advantages of such a multi-parameter analysis include: a. the enormous time savings, the resulting therapeutic added value, the reliability of the methodology even with mixed samples and the ability to standardize the objective results. With the availability of an approved in-vitro diagnostic device (CE-IVD) for human diagnostics, all prerequisites have been created to utilize these advantages in the broad routine of laboratory medicine.
Active ingredients against skin fungi
Active substances against fungal diseases are called antifungal agents . The active ingredients that are effective against skin fungal diseases include:
- Clotrimazole
- Miconazole
- Terbinafine
- Bifonazole
- Ketoconazole
- Naftifin
- Benzoic acid
- Undecylenic acid
- Ciclopirox or its ethanolamine salt ciclopiroxolamine
- Econazole
- Tioconazole
Portuguese researchers were able to show that even in low concentrations lavender oil kills various yeast and filamentous fungi that can cause skin and nail fungal diseases in humans.
Treatment indications
Treatment must be consistent and thorough with antifungal drugs that have been proven to be effective. For use in the hair area, e.g. B. on the scalp, as an alternative to ointments, liquid agents such. B. with bifonazole available. The treatment with salt or vinegar footbaths shows in some cases a quick fungicidal effect - the itching then disappears after the first application. Medication must always be used for a longer period of time until it is successful.
Fungal diseases are generally very persistent. Even after the obvious symptoms have subsided , treatment must be continued for some time (at least 6 weeks) to prevent the fungal infection from flaring up again. It is particularly important to disinfect textiles and shoes that come into contact with the skin. Stockings, for example, should be washed at at least 60 ° C, otherwise fungal spores can survive and cause new infections.
Shoes can be sprayed with a commercially available spray containing clotrimazole and thus disinfected. Also, formaldehyde is suitable for disinfection . Alcohols can be used to disinfect surfaces, but are usually too poorly effective in textiles or shoes.
Web links
Individual evidence
- ↑ V. Panasiti, RG Borroni, V. Devirgiliis, M. Rossi, L. Fabrizio, R. Masciangelo, U. Bottoni, p Calvieri: Comparison of diagnostic methods in the diagnosis of dermatomycoses and onychomycoses. In: Mycoses. Vol. 49, No. 1, 2006, pp. 26-29, PMID 16367815 , doi: 10.1111 / j.1439-0507.2005.01185.x .
- ↑ Mónica Zuzarte, Maria José Gonçalves, Carlos Cavaleiro, Jorge Canhoto, Luís Vale-Silva, Maria João Silva, Eugénia Pinto, Lígia Salgueiro: Chemical composition and antifungal activity of the essential oils of Lavandula viridis L'Hér. In: Journal of Medical Microbiology. Vol. 60, No. 5, 2011, pp. 612-618, doi: 10.1099 / jmm.0.027748-0 .
