Tinea or dermatophytoses are infectious diseases caused by certain fungi that primarily affect the skin, but also hair and fingernails and toenails.
What is tinea?
The ancient Greek name dermatophytosis is derived from the words for “skin” (derma) and “plant” (phyton). The Latin name tinea (“woodworm”) is also common. Dermatophytosis can occur on various parts of the body. The clinical picture can be very different depending on the type of fungus and body region – often there is redness, itching, scaling and blistering. The best known is probably tinea pedis, the athlete’s foot. Approximately every tenth to fifth person suffers from dermatophytosis in the course of his or her life; it is thus the most common dermatological disease of all and one of the most common infectious diseases.
Causes
Dermatophytosis is caused by so-called filamentous fungi. These are filamentous, unicellular fungi that settle in the hair, nails, and skin of humans and animals. A distinction is made between microspores, trichophytes and epidermophytes. They are transmitted to humans from the outside – either from one person to the next, via contaminated surfaces (as often happens, for example, with athlete’s foot), or through close contact with animals, especially rodents, rabbits and cats. People with a weakened immune system as well as those suffering from diabetes mellitus, circulatory disorders of the skin or obesity are significantly more likely to be affected.
Typical symptoms and complaints
- Ringworm
- Skin redness
- Itching
- Abscesses
Diagnosis and course
Dermatologists distinguish between superficial and deeper dermatophytosis. The superficial form (tinea superficialis) is usually manifested by redness and itching in limited areas of the skin, often ring-shaped and surrounded by a darker border. In some cases, there is hair loss or thinning of the hair growth in the affected region. In deeper dermatophytosis (tinea profunda) there is inflammation, which may also be accompanied by the formation of pus and crusts. It is primarily found in the area of the head and beard hair, as the pathogens penetrate deeper into the skin along the hair root. A rapid test for dermatophytosis is possible using the so-called Wood light. This is a black light lamp, in the light of which affected skin regions appear yellow-greenish. In the diagnosis of dermatophytosis, it is essential to precisely determine the causative fungus in order to enable effective treatment. For this purpose, the physician takes a sample of the infected tissue. By creating a fungal culture, information can be obtained about the exact strain of the pathogen.
Complications
Infections with dermatophytes are not uncommon and, if adequately treated, usually resolve without complications. Complications are particularly likely if the disorder is not taken seriously and therefore not treated, or if the patient’s immune system is severely compromised. In these cases, for example, tinea corporis may develop. This infection affects the entire body, including the limbs, and can cause very severe itching. Deeper dermatophytoses (tinea profunda) can also develop. These predominantly affect the head and other hairy regions. In men, the part of the face is particularly affected, where beard hairs also appear. Tinea profunda may be accompanied by purulent inflammation, which can be confused with purulent pustules similar to that of acne disease. Deeper dermatophytoses of the head may also cause the hair on the head to fall out, although only individual areas of the skull may thin out or the hair may break off with even minor exposure. In patients whose immune system is not fully functional, especially in children, persons suffering from diabetes mellitus or infected with HIV, there is also a risk that the fungal infection will take a severe course and affect the internal organs. Treatment is often also complicated by the fact that fungal spores can be transmitted very easily and therefore there is very often mutual infection between members of the same household, and pets can also be affected.
When should you go to the doctor?
Dermatophytosis can be treated at home with over-the-counter remedies. Fungicidal ointments and creams to be applied to the skin make the fungus disappear within days or weeks. A visit to the doctor should still be considered if the affected person is suffering from dermatophytosis for the first time and may not be able to classify where the redness on the skin is coming from. Reddened areas of skin can have many different causes that the layperson cannot tell apart. Differential diagnoses include contact allergy, mechanical irritation or a reaction to chemical substances such as an incorrect skin care product. The doctor can often tell at first glance whether it is dermatophytosis or not, and can then perform appropriate examinations of the reddened skin to confirm the diagnosis. Then there is nothing to prevent the patient from treating the dermatophytosis himself at home. Since tinea often occurs in connection with existing diseases such as diabetes, those affected then treat it themselves without seeing a doctor, since they already know what the redness is. However, if it does not disappear within a few days, then the doctor should still investigate the suspected dermatophytosis. It is possible that the redness has another cause or that the medication needs to be changed. It is also conceivable that the dose of over-the-counter ointments is not sufficient for persistent dermatophytosis.
Treatment and therapy
In healthy people, dermatophytoses sometimes heal without treatment; however, often a chronic course occurs without medical therapy. In mild forms of progression, treatment with ointments containing benzoic acid, for example, is often sufficient. If dermatophytosis is confirmed, antimycotics, specialized agents against fungal infestation, are used. These can be applied either in the form of creams, ointments or tinctures to the affected body region or – in severe cases – can also be administered in tablet form. During therapy, care should be taken to change linen and towels regularly and wash them at at least 60 degrees to avoid reinfection. The affected areas of the body should not be touched to avoid spreading the dermatophytes. If these points are observed, the therapy of dermatophythosis is generally unproblematic and a complete healing can be expected. Due to the good regenerative capacity of the skin, usually no visible traces remain and even broken hairs usually grow back completely.
Prevention
There have already been efforts in medical research to develop a vaccine against dermatophyte infestation; however, this did not become suitable for mass use due to strong side effects. The most effective prevention is to avoid contact with potentially infected surfaces. This includes wearing appropriate footwear in public swimming pools, communal showers and hostels. However, care should also be taken in private settings to avoid sharing towels and clothing. Dermatophytes thrive in warm, humid climates, so feet and skin folds should always be thoroughly dried; breathable, airy clothing is also beneficial in this regard. The usual hygiene precautions should also be observed when handling pets and livestock.
What you can do yourself
Patients with tinea (dermatophytosis) initially focus on treating the disease with medication. This is because self-healing may take a long time. Those affected regularly apply the prescribed drugs, usually antifungal agents to be applied to the skin, in the prescribed dose. In doing so, they observe the reaction of the diseased skin and consult the doctor in case of side effects or a delayed healing process. Since tinea (dermatophytosis) is often accompanied by severe itching of the affected areas, patients must learn to resist the itching and not scratch the areas of the skin affected by the fungus. Touching the diseased areas of skin is generally rather detrimental to healing and often aggravates the symptoms. In addition to intensifying the itching by scratching, touching also poses the risk of spreading the fungus to other areas of the body. During the disease, clothing should not lie tightly on the skin and should allow good evaporation of sweat.Natural fibers and hypoallergenic textiles that are cut as wide as possible and allow good air circulation are therefore well suited. Finally, hygiene plays an enormously important role during the disease. Patients with tinea avoid visits to public swimming pools and saunas.