Onychomycosis (nail fungus)

causative agents of fungal diseases

Onychomycosis, or, as it is popularly called, nail fungus, is damage to the nail plate and surrounding structures from a fungal infection. Nails infected with fungus change their color and transparency, become brittle, rough, thickened, flaking and crumbling. In this case, the tissue under or near the nail may become red and swollen.

Nail fungus is a very common disease. According to statistics, onychomycosis affects from 8 to 26. 9% of the world's population, and in Russia the number of people with this diagnosis ranges from 4. 5 to 15 million people.

Usually, onychomycosis is detected in patients over 40 years of age. At the same time, there are no unified statistics on the incidence of the disease in men and women, the opinions of the authors differ. In Russia, nail fungus is more common in men. At the same time, women are one and a half times more likely to visit a doctor - perhaps this is explained by a more careful attitude to the health and appearance of the nails of the feet and hands. The pictures may seem shocking.

stage of development of nail fungus

In approximately 80% of cases, the disease affects the toenails. Less commonly, onychomycosis affects the nails. Researchers have identified factors that significantly increase the risk of developing onychomycosis. They can be roughly divided into two groups.

External (exogenous) risk factors for the development of onychomycosis:

  • nail injuries;
  • long-term wearing of tight, non-breathable shoes;
  • staying in hot and humid climates.

Internal (endogenous) risk factors for the development of onychomycosis:

  • age of the patient: the disease is more common in people over 40 years old;
  • Overweight;
  • reduced immunity;
  • related diseases: diabetes mellitus, thyroid disease, varicose veins;
  • flat feet and other foot deformities;
  • long-term use of certain drugs: antibiotics, cytostatics, corticosteroids.

The family factor plays a particular role in the spread of onychomycosis. According to statistics, 55% of patients had a family history of nail fungus.

You can become infected with onychomycosis through direct contact with an infected person, as well as through household items - clothes, shoes, hygiene products (towels, towels).

In public places, the infection occurs mainly in gyms, bathrooms, saunas and swimming pools. Scales with pathogenic fungi fall on floors, benches, paths and grates. Mushrooms under such conditions continue to multiply and soon find new hosts.

the bathroom is a source of high humidity

The fungi that cause onychomycosis thrive in high humidity conditions. In addition, you can catch onychomycosis in a manicure or pedicure salon if the master does not follow the rules of hygiene and sterilization of tools.

Causes of onychomycosis

About 50 types of fungi are known that can infect the nail plate. At the same time, dermatomycetes of the genus Trichophyton account for up to 80–90% of cases of onychomycosis of the feet and up to 36% of onychomycosis of the hands.

fungi that affect the hair and nails

Dermatomycetes are microscopic fungi that attack the skin, hair and nails. The second most common cause of onychomycosis is Candida yeast. Nail candidiasis occurs in 5-10% of cases. Less common causes of onychomycosis are mold fungi - Aspergillus (Aspergillus), Fusarium (Fusarium), Scopulariopsis (Spoculariopsis).

In practice, the nail plate is damaged by several types of fungus at once. Most often it is a combination of two types of dermatomycetes or variations of "dermatomycetes + yeast", "dermatomycetes + molds". In approximately 10% of cases, the patient is infected with three or more types of fungi.

Types of onychomycosis

In Russian dermatology, three types of onychomycosis are distinguished depending on the clinical manifestations of the disease.

Main types of onychomycosis:

  • normotrophic: the shape of the nail plate does not change, while whitish and yellowish stripes are visible in the thickness of the nail;
  • hypertrophic: the nail plate noticeably thickens, becomes brittle, with jagged edges;
  • dystrophic: the nail plate thins and detaches from the nail bed.
dystrophic onychomycosis

Depending on how the fungus got on the skin and nails, there are four types of onychomycosis.

Types of onychomycosis depending on the place of penetration and spread of the pathogenic fungus in the nail plate:

  • superficial white: the fungus colonizes the upper part of the nail plate. Whitish lesions appear on the nail. As the infection spreads, the nail turns gray-brown and begins to crumble;
  • distal-lateral subungual: the fungus penetrates through the skin in the area of the nail folds or the free edge of the nail. The nail plate thickens, turns yellow, crumbles, then moves away from the nail bed;
  • proximal subungual: the fungus spreads from the skin and nail folds to the nail plate and deeper. Spots appear on the nail in the area of the hole and the nail bed. The nail plate peels off;
  • total dystrophy: the entire nail plate is affected. It looks sharply thickened and acquires a dirty yellow color. The surface of the nail becomes uneven.

Once on the nail plate or the surrounding structures, the fungal colony begins to grow towards the matrix - the growth zone, which is located at the back of the nail bed. It is believed that the faster the nail grows, the more effectively it displaces the fungal colony and the faster recovery from onychomycosis occurs. This mechanism also explains the fact that nail fungus mainly affects people over 40: their nails grow much more slowly than those of young people.

nail structure

Symptoms of onychomycosis

As onychomycosis progresses, the symptoms of the disease become more pronounced.

The main symptoms of onychomycosis:

  • a change in the color of the nail plate to yellow, black, green, brown or gray;
  • separation of the nail plate from the bed;
  • change in the thickness of the nail plate;
  • koilonychia - the nail becomes concave, in the shape of a teaspoon;
  • onychogryphosis - the nail bends like the beak of a bird of prey;
  • thickening of the nail bed;
  • change in the surface of the nail plate: formation of pits, furrows, edges;
  • inflammation of the nail fold.

Complications of onychomycosis

Without treatment, onychomycosis in patients with diabetes can lead to serious complications, such as diabetic foot - ulcerative defects of soft tissues with damage to tendons and bone structures.

diabetic foot in a patient with diabetes mellitus

In people with prolonged fungal infection, as well as against the background of immune deficiency, onychomycosis can lead to a severe allergic reaction. This is explained by the fact that the fungal colony and its metabolic products act as sensitizers - triggers to which the body reacts with increased sensitivity.

As a result, an allergic reaction is formed, which can have different manifestations: a more severe course of bronchial asthma, the appearance of outbreaks of microbial eczema and the development of urticaria.

Common complications of onychomycosis:

  • diabetic foot;
  • allergic reactions;
  • chronic erysipelas of the extremities is an infectious skin lesion;
  • lymphostasis - retention of lymph fluid in the tissues;
  • elephantiasis (elephantiasis, elephantiasis) is a progressive lymphedema, simultaneously with the replacement of subcutaneous fat with connective tissue.

Diagnosis of onychomycosis

The diagnosis and treatment of onychomycosis is carried out by a dermatologist. At the appointment, the doctor will assess the condition of the patient's nails, skin, mucous membranes and hair. He will perform dermatoscopy and examine the skin under magnification. In parallel with the examination, the specialist will collect anamnesis and question the patient about his lifestyle, quality of nutrition, household habits and care. If you suspect onychomycosis, your doctor will order laboratory tests. Examining scrapings from the nail plate will rule out or confirm the presence of a fungal infection. The doctor may also refer the patient for microscopic examination and culture.

Diabetes mellitus can significantly worsen the course of onychomycosis and lead to serious complications. Complex studies can exclude or confirm this diagnosis. A complete blood count helps to assess the general condition of the patient.

Treatment of onychomycosis

Treatment of onychomycosis can be local, systemic or combined. Corrective therapy, which is aimed at eliminating concomitant diseases, may also be required. In topical therapy, antifungal drugs 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, which eliminates the risk of side effects.

However, with local therapy, the drug cannot always reach the fungal colony, especially if it is located deep in the nail bed. Before applying topical medications, the affected part of the nail should be removed. At home, you can use a keratolytic patch - it contains a small amount of acid and can soften the nail.

Systemic therapy allows the antifungal agent to penetrate the affected area through the blood, regardless of how deeply the fungal colony is hidden.

The main types of systemic drugs for the treatment of onychomycosis:

  • antifungal agents;
  • antiseptics - have both antifungal and antibacterial effects;
  • multicomponent drugs may also contain anti-inflammatory substances.

The treatment regimen and dosage of the drug are determined by the doctor. In combined therapy, systemic and local treatment are carried out simultaneously. This allows you to increase the effectiveness of the treatment and shorten its duration.

Corrective therapy is aimed at treating concomitant diseases that can complicate the course of onychomycosis. These are mainly diabetes mellitus, pathologies of the thyroid gland and vascular diseases (for example, varicose veins). Treatment tactics are determined by the doctor and other specialized specialists, who in this case manage the patient together.

Prognosis and prevention

If you consult a doctor in time, the prognosis for onychomycosis is favorable: up to 80% of patients treated with antifungal drugs get rid of the disease forever. To prevent onychomycosis, you need to protect your feet and hands from irritating and traumatic factors and strengthen the immune system.

Measures to prevent onychomycosis:

  • change socks daily or more often if your feet are sweaty or wet;
  • air or dry shoes after wearing;
  • do not wear common slippers when visiting;
  • don't try on shoes in a store with bare feet;
  • use a personal towel for your feet;
  • use individual nail care tools (tweezers, files);
  • wear shoes in the pool or sauna;
  • monitor the variety of your diet;
  • avoid stressful situations.