In the natural microflora of humans and animals there are no pathogenic fungi. Fungi are eukaryotes devoid of chlorophyll and incapable of photosynthesis. Most fungi are saprophytes of the environment (heterotrophs) and must be fed with ready-made organic substances. The body of the fungus is represented by the mycelium, a network of thin, branched tubular filaments called hyphae. Fungi multiply by spores. Entering the tissues of a susceptible host during accidental inoculation, its favorable nutrient substrates, fungi can cause various diseases of the skin, mucous membranes and internal organs. Fungal diseases are called mycoses (from the Greek Mykes - fungus).
The causative agents of mycoses are parasitic microscopic fungi of the genus: Arthroderma, Aspergillus, Amanita, Microsporum, Penicillium, Candida, Saccharomyces, Trichophyton, Epidermophyton, etc. Systemic mycoses of internal organs are very difficult and can affect, in addition to the skin, muscles, bones, internal organs and the nervous system. Actinomycosis is a serious disease caused by radiant actinomycetes fungi, blastomycosis is a deep cutaneous mycosis, the causative agent is a pathogenic dimorphic fungus. Other diseases also belong to deep (visceral) mycoses. Superficial mycoses affect the stratum corneum, scalp, nails and mucous membranes.
The most common keratomycosis, which affects only the stratum corneum; dermatomycoses affect smooth skin, the epidermis and its appendages: hair, nails.
Depending on the type of pathogenic fungus and the localization of the pathological process, there are:
- epidermophytosis - mycosis of the skin of the inguinal folds, lower leg, interdigital folds, brushes;
- trichomycosis (from the Greek trichos - hair) - damage to the scalp, vellus hair on the body;
- ringworm (ringworm), microsporia, favus (scab);
- onychomycosis (from the Greek onychos - nail) - damage to the nails of the hands or feet with dermatophytes (less often mold or yeast).
For diseases caused by various types of pathogenic or opportunistic fungi, antifungal drugs are used. Depending on the localization of pathogenic fungi, antifungal drugs are classified into drugs for treatment:
- systemic mycoses;
- candidiasis;
- superficial mycoses.
The chemical classification divides antifungal drugs into:
antibiotics:
- polyene antibiotics (amphotericin B, amphoglucamine, natamycin, nystatin);
- non-polyene antibiotics (griseofulvin);
synthetic drugs:
- imidazole derivatives (bifonazole, isoconazole, ketoconazole, clotrimazole, miconazole, oxiconazole, homoconazole, sertaconazole);
- triazole derivatives (itraconazole, fluconazole, thermoconazole, tioconazole);
- allylamine derivatives (terbinafine, naftifine);
- morpholine derivatives (amorolfine);
- derivatives of different chemical groups: undecylenic acid ciclopirox, flucytosine, potassium iodide, etc.
onychomycosis
Onychomycosis is caused by infection of the nail plate. Most of the infection occurs in public baths, saunas, swimming pools. The scales, which contain spores and mycelium of fungi, falling in patients with onychomycosis, fall on the floor, benches, trellises, walkways, carpets and bedding. In conditions of high humidity, fungi can not only persist for a long time (years), but also multiply, which makes them an intense source of infection. A person who moves on the floor with bare feet or touches household objects with such scales can become infected, because they stick to his skin and are fixed. The infection develops after the penetration of the fungus into the structures of the nail. In the future, they begin to activate, multiply and form tunnels, passages. When affected, the nails thicken, crumble, yellow and break. Sometimes the process also affects the skin, which is accompanied by itchy, scaly rashes in the interdigital area. Such diseases are distinguished by a long and persistent course.
The likelihood of susceptibility to infections increases with age, especially in the elderly over 65, due to the presence of chronic diseases such as vegetative-vascular pathology, diabetes mellitus, peripheral circulatory disorders, osteoarthropathy of the feet, etc. nail plates.
Treatment of onychomycosis is carried out strictly according to a certain scheme for a long time - from 2 to 4 months. In therapy, antifungals are used, which have a fungistatic and fungicidal effect and affect various stages of vital activity and metabolism of pathogens. There are three main mechanisms of the antifungal action of antifungal drugs, which manifest their activity as a result:
- violations of the structure and function of the cell wall of fungi (imidazoles, triazoles);
- violation of mitosis of eukaryotic cells, inhibiting the synthesis of nucleic acids (griseofulvin);
- inhibition of transmembrane exchange processes through the cell membrane of fungi (ciclopirox).
Drugs of choice
Griseofulvin(Griseofulvinum). 125 mg is an antibiotic produced by the Penicillium nigricans mold (griseofulvum), it was isolated in 1939 and is a spiro derivative of benzofuran in the structure. The drug has fungistatic properties against all types of fungi: ringworms and epidermophytes. The mechanism of the fungistatic action is based on the ability of the drug to inhibit the cell division of filamentous fungi in metaphase, causing characteristic morphological changes (torsion, increased branching and curvature of the hyphae), disrupting the structure of the mitotic spindle and the synthesis of the wall mobile phone. To a small extent, the drug inhibits the synthesis and polymerization of nucleic acids. The drug has no antibacterial activity.
To create a sufficient concentration of the drug in the skin, long-term treatment is required - 2-3 months min. Only on new and regrown nails will you notice the first symptoms of the effectiveness of the treatment.
Important! Side effects when taking the drug include: dyspeptic disorders, dizziness, sometimes insomnia, allergic reactions, leukopenia. Griseofulvin is contraindicated in the suppression of hematopoiesis, hepatic and renal insufficiency, as well as in newborns and pregnant women. You should not prescribe the drug for transporting drivers, people engaged in high-altitude work or requiring increased attention, rapid mental and motor reactions. Patients should be warned of the development of possible cross-sensitivity to penicillin and of the increased effect of alcohol.
Ketoconazole(Ketoconazole) - a broad-spectrum active drug of the imidazole group with fungicidal and fungistatic activity; effective when taken orally with systemic and superficial mycoses, dermatomycosis and candidiasis. It is prescribed by a doctor for the treatment and prevention of fungal infections of the skin, hair, nails, genitals caused by pathogens sensitive to the drug.
When administered orally, the drug is well absorbed, dissolved and absorbed in an acidic environment.
Important! The drug is well tolerated by patients, but can cause dyspeptic symptoms (nausea, vomiting, diarrhea), very rarely allergic reactions occur in the form of hives and rashes, headache, dizziness, gynecomastia, impotence. With the simultaneous use of the drug with other drugs (fentanyl, tamsulosin, carbamazepine, salmeterol, etc. ), the concentration of the latter may increase with an increase in side effects.
Contraindicated in severe liver, kidney, pregnancy, lactation and hypersensitivity to the drug.
Ketoconazole is available in the table. Suppository of 200 mg. 400mg; 2% ointment, 15 mg; cream 20 mg / g - 15 g It is used in the form of a shampoo. The duration of treatment is determined individually.
itraconazole(Itraconazol) caps. 100mg; 10 mg / ml solution - 150 ml vial: the drug has a broad spectrum of action, selectively and specifically inhibits the enzyme that catalyzes the synthesis of fungal sterols. Scope: various infections caused by dermatophytes and / or yeasts and molds, such as candidiasis of the mucous membranes (including the vagina), cutaneous mycosis, onychomycosis, epidermomycosis, fungal lesions of the eyes (keratitis), peritoneum and other localizations. Taking Itraconazole capsules immediately after meals increases their bioavailability; the maximum concentration in a blood plasma is reached within 3-4 hours. after ingestion. The drug is well distributed in tissues susceptible to fungal infections.
Important! When using the drug, side effects from the digestive system may occur: dyspepsia (nausea, vomiting, diarrhea, constipation, loss of appetite), abdominal pain, taste disturbance; headache, dizziness, allergic reactions, alopecia, from the hematopoietic organs (rarely) - leukopenia, thrombocytopenia. Use is contraindicated in case of hypersensitivity to itraconazole and any of the components of the drug, children under 3 years of age, pregnancy and lactation.
For optimal absorption of the drug, it is necessary to take the capsules without chewing, immediately after a meal, swallow whole. A pulse therapy course for onychomycosis consists of a daily intake of 2 capsules. the drug twice a day for a week. For the treatment of fungal infections of the fingernails, two courses are recommended. For the treatment of toenail fungal infections, three courses are recommended. The interval between courses, during which it is not necessary to take the drug, is 3 weeks.
terbinafine(Terbinafine) - produced in the form: tab. 250mg; 1% ointment 15. 0 g; 1% cream - tube of 10, 15, 30 g; 1% spray, 20 ml. The drug is referred to as allylamines and is prescribed for systemic and external use. The mechanism of action of Terbinafine is associated with the inhibition of the initial phase of ergosterol biosynthesis (the main cell sterol of the fungal membrane) by inhibiting the specific enzyme squalene-2, 3-epoxidase on the fungal membrane. The drug is effective against many pathogenic fungi for humans. With local treatment, terbinafine is more effective than azole drugs, imidazole derivatives, but comparable to itraconazole and, when administered orally, is more effective than griseofulvin and itraconazole. Terbinafine is characterized by lipoidophilia, spreads rapidly in the horny layer of the epidermis, dermis, subcutaneous tissue, accumulates in the sebaceous glands, hair follicles and nails in concentrations that provide a fungicidal effect. 1 tab. terbinafine once daily results in higher cure rates and better outcomes for each efficacy criterion (including mycological treatment) than intermittent intraconazole therapy.
Naftifin(Naftifine) cream 1% - 15, 30 g; The 1% solution of 10, 20, 30 ml, is an allylamine derivative. The mechanism of action is associated with the inhibition of the activity of the enzyme squalene-2, 3-epoxidase, inhibition of the biosynthesis of ergosterols, which leads to a violation of the synthesis of the cell wall. Naftifine has a broad spectrum of action, acting fungicidal against dermatophytes (such as Trichophyton, Epidermophyton, Microsporum), molds (Aspergillus spp. ), Yeast-like fungi (Candida spp. , Pityrosporum) and other fungi, for example (Sphenor scororichosis) . . . The drug has an anti-inflammatory effect, reduces itching. When applied externally, it penetrates well into the skin, creating stable antifungal concentrations in its various layers.
The duration of treatment with Naftifin ranges from 2 weeks to 6 months. When using the drug, dryness and redness of the skin, a burning sensation may occur, all these side effects are reversible and do not require cancellation.
amorolfine(Amorolfine) nail polish 5% - 2, 5 and 5 ml, - a preparation for external use, has a broad spectrum of action, providing a fungistatic and fungicidal action due to damage to the cytoplasmic membrane of the fungus by disrupting biosynthesis of sterols, due to the inhibition of the enzymes 14– gamma demethylase and 7 gamma isomerase. The drug is active against both the most common and rare pathogens of fungal nail infections of dermatophytes: Trichophyton spp. , Microsporum spp. , Epidermophyton spp. ; molds: Alternaria spp. , Scopulariopsis spp. , Hendersonula sppi. ; mushrooms of the Dematiaceae family: Cladopsorium spp. , Fonsecaea spp. , Wangiella spp. ; dimorphic fungi Coccidioides spp. , Histoplasma spp. , Sporothrix spp.
When applied to the nails, the drug penetrates the nail plate and further into the nail bed, almost completely within the first 24 hours. The effective concentration remains in the affected nail plate for 7-10 days. after the first application. Systemic absorption is negligible. It applies externally. The drug is applied to damaged fingernails or toenails 1-2 times a week. The duration of treatment is determined individually and depends on the indications for use. Side effects are rare and appear in the form of itching, burning at the application site. Not prescribed for young children and babies.
undecylenic acidand its salts - antifungal drugs for external use, which have a fungistatic and fungicidal effect against dermatophytes, when combined with zinc or copper salts - zinc undecylenate or copper undecylenate - the activity increases. Zinc, which is part of the drug, has an astringent effect, reduces the manifestations of signs of skin irritation and promotes faster healing.
- Undecylenic acid + zinc undecylenate (TN, 30g tube ointment, 25g ointment in bottles);
- Undecylenic acid + copper undecylenate + HCV glycerol - are used to treat and prevent fungal skin diseases caused by drug-sensitive fungi (dermatophytes).
The preparations are applied to a clean and dry surface of the affected skin 2 times a day (morning and evening). The duration of the course of treatment is 4-6 weeks and depends on the nature, effectiveness and course of the disease. After the disappearance of the clinical signs of the disease, they continue to be used once a day. For preventive purposes - 2 times a week.
Important! Contraindication to the use of the drug is hypersensitivity to undecylenic acid and its derivatives.
Cyclopirox(Ciclopirox) nail polish 8%, fl. 3 g, is a broad spectrum antifungal drug that inhibits the capture of precursors for the synthesis of macromolecules in the cell membrane. Applied externally for the treatment and prevention of fungal infections of the skin, mucous membranes, nails, fungal vaginitis and vulvovaginitis.
The drug is applied 1-2 times a day to the affected nail, the duration of use depends on the severity of the lesion, but should not exceed 6 months.
Treatment of onychomycosis should take place under the close supervision of a dermatologist. As a rule, rational therapy of the etiotropic complex is used. Clinical symptoms usually decrease or disappear a few days after taking an antifungal. However, in order to avoid relapse of the disease, the course of treatment must be carried out completely. Against the background of clinical care, anti-relapse therapy is often performed, aimed at preventing reinfection.