Foot mycosis (dermatophytosis) is an infectious disease caused by pathogenic or opportunistic fungi. In ringworm, the skin on the legs flakes and itches a lot and, in severe cases of the disease, it turns red and swells.
Definition of disease
Foot mycosis, or dermatophytosis, is an infectious disease caused by dermatophyte fungi. In total, 43 species of dermatophytes are known, 30 of which lead to foot mycosis. Most often these are the fungi Trichophyton rubrum (90%), Trichophyton mentagrophytes and, less commonly, Epidermophyton. Mycosis of the feet is caused much less frequently by fungi of the genus Candida and molds Scytalidium dimidiatum, Scytalidium hyalinum.
All dermatophytes have keratinolytic activity: they are capable of dissolving keratin, the fibrous protein that forms the upper part of the skin of humans and animals. The skin is damaged.
Once on the skin, the fungi are directed to the most vulnerable places - the junctions between the cells of the epidermis. There they penetrate and begin to grow actively. However, fungi rarely penetrate deeper than the granular layer of the skin. They are usually limited to only the upper keratinized tissues.
Prevalence of foot mycosis
Skin mycoses, including foot mycoses, are found in every country in the world. The share of these diseases in the structure of all dermatological diseases reaches 37–40%.
At the same time, cutaneous mycoses occur more frequently - in approximately 30% of cases.
According to dermatologists, up to 20% of the adult population suffers from foot mycosis. The pathology is found twice as often in men.
Among people over 70 years old, foot fungus is found in almost all patients - this is explained by the fact that elderly people often have chronic diseases associated with metabolic disorders, as well as vascular pathologies such as varicose veins.
Foot mycosis infection usually runs in families - through direct contact with the skin of an infected person. There are also known cases of infection when sharing clothes, shoes and household items.
The infection usually affects both feet at the same time and partially spreads to the nail plates. Without treatment, the disease can also affect the skin on the palm of the hand - usually on the working hand. This condition is called two-foot-one-hand syndrome.
Causes of foot mycosis
Most often, foot mycosis is caused by dermatophyte fungi - Trichophyton rubrum, Trichophyton mentagrophytes and Epidermophyton floccosum. Much less often, the disease is provoked by fungi of the genus Candida (Candida) and mold (Scytalidium dimidiatum, Scytalidium hyalinum).
According to some studies, the proportion of dermatophytes in the structure of agents causing foot mycosis is gradually decreasing. Candida mushrooms come to the fore.
Risk factors for developing foot mycosis:
- violation of personal hygiene;
- sharing shoes (e. g. at bowling alleys, skate shops and ski rentals);
- visit public baths, swimming pools, beaches;
- climatic features: the risk of getting sick is greater in countries with a subtropical and tropical climate - this is due to increased humidity and ambient temperature;
- constant use of closed and tight shoes (this happens among military personnel, miners, workers in the textile and metallurgical industries);
- frequent injuries to the toes due to flat feet, corns, calluses;
- failure to comply with sanitary standards during a pedicure;
- impaired blood supply to the legs;
- immunodeficiency conditions, including HIV;
- chronic dermatoses;
- obesity;
- diabetes;
- chronic venous insufficiency;
- taking certain medications (systemic glucocorticosteroids).
Symptoms of foot mycosis
The symptoms of foot mycosis, as well as the characteristics of the disease's treatment, depend on its clinical form.
Squamous (squamous-hyperkeratotic) form of foot mycosis
In most cases, the causative agent of the scaly form of foot mycosis is the dermatophyte Trichophyton rubrum.
At the initial stage of the disease, the patient is bothered by moderate peeling of the skin between the fingers - the skin scales are abundant, thin and silvery in color. Then, as the disease spreads to the lateral and dorsal surfaces of the feet, a characteristic inflammatory ridge appears and the skin in the affected areas thickens. Over time, the patient develops onychomycosis - nail fungus.
Intertriginous (interdigital) form of foot mycosis
This form often develops against the background of severe foot sweating. The disease affects the spaces between the toes and is accompanied by redness, swelling and maceration (softening and loosening of the skin). Erosion and cracks often form. Many patients report itching, burning and pain.
Often, there is simultaneous infection of the skin of the feet by dermatophyte fungi (usually Trichophyton mentagrophytes var. interdigitale) and the bacteria Staphylococcus aureus.
Dyshidrotic form of foot mycosis
As a rule, the causative agent of this form of foot mycosis is Epidermophyton floccosum (scaly epidermophyton).
The dyshidrotic form of foot mycosis, as a rule, is more severe and is accompanied by painful itching and pain. Thickly covered blisters form on the skin. Merging, they form large multi-chamber bubbles, which, after opening, turn into reddish-pink wet erosions, and then into brown crusts.
The disease is difficult to treat and often recurs.
A characteristic feature of the dyshidrotic form is damage to the arch of the foot, interdigital folds and the skin of the fingers. The process can then spread to the heels, the lower lateral surfaces of the feet, and even the skin below the ankles.
If a bacterial infection occurs, the patient may develop a fever and regional lymph nodes will enlarge. Swelling appears on the foot and the skin becomes wet. The intense pain makes it difficult for the patient to walk.
Exudative-dyshidrotic form of mycosis of the feet
Most often, the exudative-dyshidrotic form of foot mycosis is caused by the fungus Trichophyton rubrum (red trichophyton).
The skin between the toes is affected first. Then the process spreads to the sole, dorsal and lateral surfaces of the foot and nail plates. Blisters and erosions appear on the skin, which become covered with crusts. The skin becomes wet and can become infected.
Erased form of foot mycosis
The erased form is identified by some researchers. It is believed to occur a few days after infection with the fungus.
The skin in the interdigital folds begins to peel off. There may also be slight peeling on the soles and sides of the feet. Patients may ignore unpleasant symptoms but still infect others.
Acute form of foot mycosis
The acute form of foot mycosis is the result of an exacerbation of the dyshidrotic or intertriginous (interdigital) form.
The disease begins acutely: a large number of blisters appear on the skin of the feet, and then on the legs. The skin swells. Nodules then form on the hands and lower third of the forearms.
After the blisters open, erosions appear, surrounded by remnants of loose skin. They merge, turning into extensive weeping surfaces, often with purulent discharge.
The disease is often accompanied by fever, deterioration in the patient's general condition and sharp pains in the affected hands and feet. The inguinal and femoral lymph nodes enlarge and become painful.
Vesiculobullous (inflammatory) form of mycosis of the feet
The inflammatory form of foot mycosis is generally identified by foreign authors, often defining it as acute. It can develop from a chronic interdigital form of dermatophytosis.
As a rule, the causative agent of the vesiculobullous form is the dermatophyte Trichophyton rubrum.
Main symptoms: intense itching, rashes, located mainly on the sole, base and sides of the fingers, on the back of the foot. Swollen areas with blisters may appear on the surface. The bubbles can merge or remain unchanged for a long time - if the tire (upper part) is thick enough.
Often, the nail plates are also involved in the process - onychomycosis develops.
Ulcerative form of foot mycosis
The ulcerative form (in foreign literature it is called deep) is one of the complications of foot mycosis, caused by the addition of a bacterial infection.
Extensive deep purulent ulcers form on the soles of the feet. The patient experiences severe pain and, as a result, difficulty walking.
Complications of foot mycosis
Cracks and ulcers on the skin that appear at the site of ringworm are the entry points for bacterial infections. However, it is more difficult to treat these infections - this is explained by the fact that fungi produce special substances that increase the resistance of bacteria to drugs.
The most common complications of foot mycosis:
- allergic dermatitis of infectious and medicinal origin;
- pyoderma - pustular skin diseases (cellulitis, lymphangitis, phlegmon, osteomyelitis of the bones of the foot), which can cause deep and long-lasting wounds on the skin;
- plantar warts;
- microbial eczema is a chronic inflammatory disease in which the skin itches and turns red, forming blisters filled with liquid;
- general decrease in immunity and impaired microcirculation in the lower extremities (usually develops in patients with diabetes mellitus and varicose veins);
- spread of the disease to the skin of the hands and nails;
- deterioration in quality of life: in acute forms of ringworm it is difficult to wear shoes and lymphadenitis causes fever and health problems.
Diagnosis of foot mycosis
The dermatologist-mycologist deals with the diagnosis and treatment of foot mycosis.
During the consultation, the doctor will assess the condition of the patient's nails, skin, mucous membranes and hair. He will perform a dermoscopy - examine the enlarged skin. At the same time as the examination, the specialist will take an anamnesis and ask the patient about their lifestyle, quality of diet, domestic habits and care.
If you suspect athlete's foot, your doctor will order laboratory tests.
Examination of skin scrapings will rule out or confirm a fungal infection.
The doctor may also refer the patient for microscopic examination and culture.
The sowing, or cultural method, allows you to obtain more accurate information about the causative agent of the disease, although it takes longer - usually a month.
Diabetes mellitus can significantly worsen the course of foot mycosis and lead to serious complications. Complex studies can exclude or confirm this diagnosis.
A complete blood count helps assess the patient's general condition.
The clinical blood test is a blood test that allows you to assess your general health status, identify inflammation, bacterial, viral and fungal infections, and can also help diagnose anemia, diseases of the hematopoietic organs, allergic reactions and autoimmune diseases.
Also, before recommending antifungal therapy, the doctor may prescribe the patient a biochemical blood test - this study will determine the level of bilirubin and liver enzymes ALT and AST. This information will help the doctor choose the dosage of the medication and minimize the risk of side effects.
Foot mycosis treatment
The treatment of foot mycosis is carried out in two stages.
In the first phaseIf there is acute inflammation, lotions are used: aqueous solutions of bituminous ammonium sulfonate, agents with antiseptic properties (Casellani liquid, 1% aqueous solution of brilliant green). Then pastes and ointments are prescribed that contain antifungal medications and glucocorticosteroids.
In case of intense crying (in the acute phase) and the addition of secondary infection, anti-inflammatory solutions are used in the form of lotions, as well as combined antibacterials in the form of creams and solutions.
The basis of therapy is the use of antimycotic agents - antifungals.
On the main stageThe treatment uses antifungal medications designed to destroy pathogenic fungi. Most often, these medicines are produced in the form of ointments, creams or solutions.
If the patient is bothered by severe itching, the dermatologist may prescribe antihistamines. They are usually taken for 10 to 15 days, until the unpleasant symptom disappears completely.
When nails are damaged, antifungal agents are used - they are applied directly to the nail plate and nail folds. In this case, the medicine is concentrated on the surface of the nail and does not penetrate the bloodstream, eliminating the risk of side effects.
If external medications do not produce an effect, systemic antimycotic agents are prescribed.
The treatment regimen and dosage of medications are determined by the doctor. During treatment, you must visit a podiatrist at least once a month.
Prognosis and prevention
If you consult a doctor in a timely manner, the prognosis for mycosis of the feet is favorable: most patients treated with antifungal drugs get rid of the disease forever.
To prevent ringworm, it is necessary to protect your feet and hands from irritating and traumatic factors and strengthen your immune system.
Measures to prevent onychomycosis:
- change socks every day or more often if your feet are sweaty or wet;
- airy or dry shoes after use;
- use an antifungal UV shoe dryer;
- do not use shared slippers during the visit;
- do not try on shoes in a store barefoot;
- use a personal towel for your feet;
- use individual tools for nail care (tweezers, files);
- wear shoes in the pool or sauna;
- monitor the diversity of your diet;
- avoid stressful situations.
Common questions
How to cure foot fungus?
To treat fungus on the legs, antimycotic medications are generally used, which are available in the form of creams, ointments and solutions. The dermatologist must choose the most effective medication and determine its dosage.
Why do my feet itch?
One of the causes of itchy feet is foot mycosis, an infectious disease caused by dermatophyte fungi.