Ringworm: Information & ringworm specialists

Leading Medicine Guide Editors
Author
Leading Medicine Guide Editors

Tinea corporis (corpus = trunk, body) or ringworm is a fungal infection of the body. It occurs on the back, chest and stomach. Pathogens are very frequently transmitted from animals to humans (zoophilic species). Transmission from person to person (antrophilic species) is also possible. Ringworm can usually be treated well with local therapies.

Here you will find further information and selected ringworm specialists.

ICD codes for this diseases: B35.4

Article overview

Causative pathogens of tinea corporis and their frequency

Ringworm is medically known as tinea corporis and is also known as a body fungal disease. It is caused by certain fungi known as dermatophytes. These fungal pathogens break down human keratin. This is an important component of nails, hair and cornea.

Dermatophytes are extremely resistant to dehydration. There are a total of 40 different species. In Central Europe, Trichophyton rubrum is the most common dermatophyte pathogen strain.

In children and adolescents, zoophilic dermatophytes are the main cause of ringworm. These are pathogens that are mainly transmitted by pets such as

  • hamsters,
  • mice,
  • rabbits,
  • guinea pigs or
  • rats

originate.

After entering the human body, the dermatophytes spread around the site of entry. There they cause inflammation. The inflammation caused by zoophilic dermatophytes is usually more intense.

Tinea corporis is one of the most common skin diseases of all. The percentage frequency of the individual dermatophytes is:

  • T. rubrum: 66 percent
  • M. canis: 12 percent
  • T. tonsurans: 9 percent
  • T. mentagrophytes: 8 percent
  • T. verrucosum: 2 percent
  • Epidermophyton floccosum: 2 percent

Risk factors for the development of ringworm

Favorable factors for infection with the body fungus are a moist, warm skin environment, for example

  • after swimming,
  • sweating during physical work or
  • a generally warm and humid climate.

Other risk factors are

In addition, ringworm occurs much more frequently with pathological skin sensitivity. Such a skin sensitivity would be neurodermatitis, for example.

Older people and children are also more frequently affected by ringworm.

Symptoms of tinea corporis

Ringworm is typically characterized by circular, marginal lesions with

  • scaling,
  • redness,
  • small papules and
  • sometimes also small pustules.

The center of the circular lesions is usually pale. Those affected suffer from itching at these foci. The marginal accentuation helps to distinguish tinea corporis from eczema. Eczema always shows the maximum of its changes in the center and weakens towards the edge.

The foci expand slowly - often over a period of weeks - to the periphery. In the process, new foci appear again and again.

However, the infection can also lie deeper. In this case, very severe inflammatory reactions are triggered. These include

Patients also suffer from fatigue and fever. The severe inflammation indicates that this fungus is poorly adapted to humans. The animals themselves often only show very discrete signs of disease.

If ringworm remains untreated for too long, it can take a chronic course. It is also possible to infect other people.

People with a weakened immune system are at further risk. Tinea corporis can also affect internal organs.

Hautpilz, hier Tinea corporis
Ringworm on the armpit of a man © RandomizeTH | AdobeStock

Diagnosis of ringworm

Symptoms such as skin irritation, redness and itching can also occur with other diseases. A doctor should therefore clarify the cause of these symptoms.

Diseases with similar symptoms are, for example

  • Seborrheic and nummular eczema
  • Pityriasis rosea (skin disease with scaling and redness)
  • Psoriasis (psoriasis)
  • Pityriasis versicolor (bran lichen)

The doctor will first inspect the skin thoroughly. He will take a swab of infected material. This is then examined under the microscope. If there is an urgent clinical suspicion, an optical brightener can also be added. This facilitates or improves the diagnosis.

To find out the exact genus and type of fungus of the pathogen, a fungal culture is created. The cells taken from the swab are cultivated on a special culture medium. Depending on the pathogen, this can take around three to six weeks.

The exact identification of the pathogen is important for

  • a systemic therapy tailored to it and
  • the detection of chains of infection

of essential importance.

In some cases, further examinations may also be necessary. These include, among others:

  • Examinations with the Wood light. This is a lamp that can produce UVA rays with a wavelength of up to 365 nm (known as black light). This allows specific types of dermatophytes to be identified. If tinea corporis is present, the affected regions appear in a yellow-green light.
  • Creation of subcultures to classify the pathogens.
  • Sometimes it is also necessary to test the patient's tolerance to specific antifungal medications.
  • Use of the DTM medium to differentiate between molds and dermatophytes.
  • Differentiation of dermatophyte strains with the aid of genetic tests. This is only necessary if conventional methods are not sufficient.

Treatment of ringworm

Accurate diagnosis is the prerequisite for successful treatment. The diagnostic data are decisive for the selection of the antimycotic (antifungal agent).

Topical therapy of tinea corporis

Normally, a local, externally applied therapy is used. This is referred to as topical therapy. The antimycotics are applied directly to the affected areas of skin.

Recognized classes of active ingredients include

  • Azoles: miconazole, clotrimazole, bifonazole, econazole, sertaconazole and tioconazole
  • Hydroxypyridones: ciclopiroxolamine
  • Allylamines: Terbinafine, naftafin
  • Morpholines: Amorolfine

Depending on the severity and localization, these medications are available as

  • solution,
  • gel,
  • cream,
  • powder or
  • paste

available. The choice of applications differs for the various preparations.

Most drug classes inhibit ergosterol biosynthesis in the fungal cell membrane. Ergosterol is a component of the so-called cytoplasmic membrane. By inhibiting the biosynthesis, the function of the membrane is considerably restricted. The growth and multiplication of the pathogens is therefore curbed.

If treatment is discontinued immediately after the symptoms have disappeared, recurrences can develop. This means that the inflammation can flare up again because the pathogens have not been killed off. Treatment must therefore be continued for up to three or four weeks after clinical healing.

Systemic therapy of tinea corporis

Topical therapy is usually sufficient. Sometimes, however, it is unsuccessful or the ringworm is too extensive. Systemic therapy is then prescribed. The patient takes medication that acts on the entire organism and not just locally.

Systemic therapy is also influenced by

  • the age of the patient and
  • body weight in children and
  • possible interactions with other medications

play a role.

The following medications are used for this form of therapy:

  • Griseofulvin microfine
  • Azoles: Itraconazole
  • Allylamine: Terbinafine

As a rule, treatment is carried out on an outpatient basis. In some cases, inpatient treatment may also be necessary. This is especially possible for particularly severe forms of the disease.

Systemic therapy should always be combined with topical therapy, especially in children. This achieves immediate effectiveness and prevents the spread or infection. Imidazole or azole derivatives are mainly used for this in children.

Tinea corporis usually shows a very favorable course. After treatment, the foci of inflammation heal without leaving any traces. However, if the infection is not treated, it takes a chronic course.

For a long time, griseofulvin was the only approved preparation for the systemic treatment of children and adolescents. Compared to other antimycotics, however, its efficacy is considerably lower and an increased dosage of up to 25mg/kg bw/day is recommended. Depending on the pathogen, the duration of treatment is between two and eight weeks.

In addition to griseofulvin, fluconazole is also suitable for the treatment of patients from the age of one. One disadvantage, however, is its interaction with various other medications.

Treatment during pregnancy and breastfeeding

Clotrimazole can be used for the local treatment of dermatophytes during pregnancy and breastfeeding. Other antimycotics are not recommended during this time, as there are no exact studies available.

If there is a compelling indication for another active substance during breastfeeding, it should only be used

  • on small areas and
  • temporarily

be used temporarily. Systemic therapy during pregnancy should only be carried out in the event of a life-threatening situation.

Systemic antimycotics are also not recommended during breastfeeding. Azoles can pass into breast milk.

If systemic therapy is unavoidable during this time, fluconazole is the drug of choice. It has a relatively favorable spectrum of side effects. All other systemic antimycotics should be avoided during breastfeeding.

Prevention of tinea corporis

Dermatophytes prefer moist regions of the skin. The body should therefore be kept as dry as possible .

Especially after swimming, it is advisable to change out of wet swimwear immediately. Sweaty skin is also an ideal breeding ground for fungi. For this reason, you should always have a change of clothes with you in summer or wear breathable clothing.

Clothes, pillowcases and blankets should also be washed at 90 degrees. This kills the germs and prevents the spread of ringworm again. Objects such as combs or brushes can also be sprayed with fungicidal disinfectants.

If ringworm is suspected, action should be taken as early as possible. Prophylactic measures are otherwise very difficult to take. The fungal pathogens often pass from animals to humans and animals hardly show any symptoms when infected.

References

Hahn, Helmut: Medizinische Mikrobiologie und Infektiologie, Springer Medizin Verlag Heidelberg 1991
Whatsapp Facebook Instagram YouTube E-Mail Print