Mycosis of the foot (dermatophytosis) is an infectious disease caused by pathogenic or opportunistic fungi. In the case of mycosis, the skin of the legs peels off and itches very much, and in severe cases of the disease, it becomes red and swollen.
Definition of the disease
Mycosis or dermatophytosis of the foot is an infectious disease caused by dermatophyte molds. A total of 43 dermatophyte species are known, of which 30 lead to foot mycosis. Most often, these are Trichophyton rubrum (90%), Trichophyton mentagrophytes and, more rarely, Epidermophyton fungi. Athlete's foot is much less often caused by fungi belonging to the genus Candida and the molds Scytalidium dimidiatum and Scytalidium hyalinum.
All dermatophytes have a keratinolytic effect: they can dissolve keratin, the fibrous protein that makes up 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 inside and begin to actively grow. However, fungi rarely penetrate deeper than the granular layer of the skin. They are usually limited to the upper, keratinized tissues.
Occurrence of foot mycosis
Mycoses of the skin, including mycoses of the feet, can be found in all countries of the world. The proportion of these diseases in the structure of all dermatological diseases reaches 37-40%.
At the same time, mycoses of the skin occur most often - in about 30% of cases.
According to dermatologists, 20% of the adult population suffers from foot mycosis. The pathology occurs twice as often in men.
Among people over 70, athlete's foot is found in almost every second patient - this can be explained by the fact that older people usually have chronic diseases associated with metabolic disorders, as well as vascular pathologies, such as varicose veins.
Infection with mycosis of the foot usually occurs in the family - through direct contact with the skin of an infected person. Cases of infection are also known when clothes, shoes and household items are shared.
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 of the palm - usually on the working hand. This condition is known as two legs 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 pathogens of foot mycosis gradually decreases. Candida fungus comes to the fore.
Risk factors for the development of foot mycosis:
- violation of personal hygiene;
- sharing shoes (e. g. in bowling alleys, skate and ski rentals);
- visiting public baths, swimming pools, beaches;
- climatic characteristics: the risk of disease is higher in countries with a subtropical and tropical climate - this is due to increased humidity and ambient temperature;
- constantly wears closed, tight shoes (this happens among military personnel, miners, workers in the textile and metallurgical industries);
- frequent injuries of the toes due to flat feet, calluses, corns;
- non-compliance with sanitary rules during pedicure;
- damage to the 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 treatment of the disease, depend on its clinical form.
Scaly (squamous-hyperkeratotic) form of foot mycosis
In most cases, the causative agent of the squamous form of foot mycosis is the dermatophyte Trichophyton rubrum.
At the initial stage of the disease, the patient is disturbed by moderate peeling of the skin between the fingers - the scales on the skin are abundant, thin and silvery in color. Then, as the disease spreads to the side and back of the leg, a characteristic inflammatory ridge appears, and the skin in the affected areas thickens. Over time, the patient develops onychomycosis - nail fungus.
Intertriginal (interdigital) form of foot mycosis
This form often develops against the background of heavy sweating of the feet. The disease affects the spaces between the fingers and is accompanied by redness, swelling and maceration (softening and loosening of the skin). Erosion and cracks often occur. Many patients report itching, burning and pain.
It often happens that the skin of the feet is infected simultaneously with dermatophyte fungi (usually Trichophyton mentagrophytes var. interdigitale) and the bacterium Staphylococcus aureus.
Dyshidrotic form of foot mycosis
The causative agent of this form of foot mycosis is usually Epidermophyton floccosum (flaky epidermophyton).
The dyshidrotic form of foot mycosis is usually more severe and involves painful itching and pain. Thick covering blisters form on the skin. They merge to form large, multichambered blisters, which, after opening, turn into moist pink-red 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 skin of the arch of the foot, the interdigital folds and the fingers. The process can then spread to the heels, the lower sides of the feet, and even the skin under the ankles.
In the case of a bacterial infection, the patient may develop a fever and the regional lymph nodes may become enlarged. The leg will swell and the skin will be moist. Severe pain makes it difficult for the patient to walk.
Exudative-dyshidrotic form of foot mycosis
Most often, the exudative-dyshidrotic form of foot mycosis is caused by the fungus Trichophyton rubrum (red trichophyton).
First, the skin between the fingers is affected. Then the process spreads to the sole, the back and side of the foot, and the nail plates. Blisters and erosions appear on the skin, which are then covered with a crust. The skin will become moist and may become infected.
Deleted form of foot mycosis
The deleted form is identified by some researchers. This is believed to occur a few days after the fungal infection.
In the interdigital folds, the skin begins to peel. Slight peeling may also occur on the soles and feet. Patients may ignore unpleasant symptoms, but still infect others.
Acute form of foot mycosis
The acute form of mycosis of the foot 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 the legs. The skin swells. Lumps then form on the hand and lower third of the forearm.
After the blisters open, erosions appear, surrounded by loose pieces of skin. They merge and become extensive weeping surfaces, often with purulent discharge.
The disease is often accompanied by fever, worsening of the patient's general condition, and sharp pain in the affected hands and feet. Inguinal and femoral lymph nodes become enlarged and painful.
Vesiculobullous (inflammatory) form of foot mycosis
The inflammatory form of foot mycosis is usually identified by foreign authors, often defined as acute. It can develop from the chronic interdigital form of dermatophytosis.
The causative agent of the vesiculobullous form is usually the dermatophyte Trichophyton rubrum.
Main symptoms: severe itching, skin rashes, mainly localized on the soles, the bases and sides of the fingers, and the back of the feet. Blistered areas on the surface may swell. 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 mycosis of the foot
The ulcerative form (called deep in foreign literature) is a complication of mycosis of the foot caused by a bacterial infection.
Extensive, deep purulent ulcers form on the soles. The patient feels severe pain and has difficulty walking as a result.
Complications of foot mycosis
Cracks and ulcers appearing on the skin at the site of mycosis are the gateways to bacterial infections. However, the treatment of such infections is more difficult - this can be explained by the fact that fungi produce special substances that increase the resistance of bacteria to drugs.
The most common complications of foot mycosis are:
- infectious and medicinal allergic dermatitis;
- pyoderma - pustular skin diseases (cellulitis, lymphangitis, phlegmon, osteomyelitis of the bones of the leg), which can lead to deep, long-lasting skin wounds;
- plantar warts;
- microbial eczema is a chronic inflammatory disease in which the skin itches, reddens, and blisters in a liquid state;
- a general decrease in immunity and impaired microcirculation in the lower limbs (usually develops in patients with diabetes and varicose veins);
- the spread of the disease to the skin of the hands and nail plates;
- deterioration of the quality of life: in acute forms of mycosis, it is difficult to wear shoes, and lymphadenitis leads to fever and poor health.
Diagnosis of foot mycosis
Mycosis of the feet is diagnosed and treated by a dermatologist-mycologist.
During the appointment, the doctor assesses the condition of the patient's nails, skin, mucous membrane and hair. He will perform a dermatoscopy - examine the skin under magnification. In parallel with the examination, the specialist collects an anamnesis and asks the patient about his lifestyle, the quality of his diet, his household habits, and his care procedures.
If athlete's foot is suspected, your doctor will order laboratory tests.
Examination of the skin scraping excludes or confirms a fungal infection.
The doctor may also refer the patient for microscopic examination and culture.
Sowing, or the culture method, allows us 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 tests can exclude or confirm this diagnosis.
A complete blood count helps assess the patient's general condition.
A clinical blood test is a blood test that allows you to assess your general health, identify inflammation, bacterial, viral, and fungal infections, and can help diagnose anemia, hematopoietic disorders, allergic reactions, and autoimmune diseases.
In addition, before recommending antifungal therapy, the doctor may prescribe a biochemical blood test for the patient - this test determines the level of bilirubin and the liver enzymes ALT and AST. Such information helps the doctor choose the dose of the drug and minimizes the risk of side effects.
Treatment of foot mycosis
The treatment of foot mycosis is carried out in two stages.
In the first stageIn case of acute inflammation, lotions are used: aqueous solutions of ammonium bituminous sulfonate, agents with antiseptic properties (Castellani liquid, 1% brilliant green aqueous solution). Then pastes and ointments are prescribed, which contain antifungal and glucocorticosteroid drugs.
In the case of strong crying (in the acute phase) and the addition of secondary infection, anti-inflammatory solutions are used as lotions, as well as combined antibacterial drugs in the form of creams and solutions.
The basis of the therapy is the use of antimycotic - antifungal - agents.
On the main stagethe treatment uses antifungal drugs aimed at killing the causative fungi. Most often, such drugs are produced in the form of ointments, creams or solutions.
If the patient is bothered by severe itching, the dermatologist can prescribe antihistamines. It is usually taken for 10-15 days until the unpleasant symptom disappears completely.
If the nails are damaged, antifungal agents are used - they are applied directly to the nail plate and nail folds. In this case, the drug is concentrated on the surface of the nail and does not penetrate into the bloodstream, eliminating the risk of side effects.
If external drugs do not work, systemic antifungal agents are prescribed.
The treatment regimen and the dosage of the drugs are determined by the doctor. During treatment, you should visit a podiatrist at least once a month.
Prognosis and prevention
If you consult a doctor in time, the prognosis of mycosis of the feet is favorable: most patients treated with antifungal drugs get rid of the disease forever.
To prevent mycosis, you need 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;
- after wearing air or dry shoes;
- use an anti-fungal UV shoe dryer;
- do not wear shared slippers when visiting;
- don't try on shoes in a store with bare feet;
- use a personal towel for your feet;
- use unique tools for nail care (tweezers, files);
- wear shoes in the pool or sauna;
- monitors the diversity of the diet;
- avoid stressful situations.
F. A. Q
How to cure athlete's foot?
Antimycotic drugs are usually used to treat foot fungus, which are available in the form of creams, ointments, and solutions. The dermatologist must select the most effective drug and determine the dosage.
Why do my feet itch?
One of the causes of itchy feet is foot mycosis, an infectious disease caused by dermatophyte fungi.