Fungal diseases (mycoses) constitute a significant part of the infectious pathology of the skin. The causative agents of mycoses are anthropophilic fungi that are parasitic in humans, zoophilic, carried by animals, as well as opportunistic organisms, mainly yeast-like fungi of the genus Candida.
One of the reasons for the significant prevalence of mycosis in the population can be considered a lack of awareness of the sources and routes of distribution, clinical manifestations and preventive measures of infection, as well as a later visit to a doctor, which leads to a chronic course of diseases. The increase in the incidence of candidiasis is associated with the widespread use of modern therapies, environmental pollution, increased background radiation and other factors that weaken the body’s defenses. According to the WHO, only about 5% of all mycoses are primary diseases, in other cases these are secondary processes that develop against the background of basic disorders of various origins.
There are superficial mycoses of smooth skin – keratomycosis and dermatophytosis (dermatomycosis), in which the epidermis, dermis and skin appendages are affected – nails, hair.
Keratomycosis is multicolored (pityriasis) versicolor. The most common disease from the group of dermatophytosis is mycosis of the feet (hands). Often there is mycosis due to yeast-like fungi of the genus Candida, superficial candidiasis of the skin.
Versicolor
Multi-colored lichen is a fungal disease whose pathogen Pityrosporum orbiculare (Malassezia furur) belongs to yeast. The disease is quite widespread in all countries, young and middle-aged people are ill.
Etiology. Pityrosporum orbiculare as a saprophyte is on the skin of a person and, under favorable conditions, causes clinical manifestations.
Pathogenesis. Factors contributing to the development of the disease have not yet been precisely determined, however, the disease is more common in people suffering from excessive sweating, changes in the chemical composition of sweat, diseases of the gastrointestinal tract, endocrine pathology, autonomic-vascular disorders, and also with immune deficiency.
Clinic. The disease is characterized by the presence of small spots on the skin of the chest, neck, back, abdomen, less often the upper and lower extremities, axillary and inguinal-femoral areas, which are initially pink in color, then light and dark brown, with slight peeling, sometimes it can be hidden and come to light only when scraping. Rashes often merge and form extensive areas of skin lesions. After tanning, as a rule, white spots remain as a result of increased peeling. The disease is characterized by a long course with frequent exacerbations.
Diagnosis and differential diagnosis. The diagnosis is made on the basis of clinical manifestations, the detection of the pathogen in the skin flakes during microscopic examination and the characteristic yellow or brown glow under a Wood fluorescent lamp, a positive test with iodine. It is necessary to differentiate the disease in the acute stage from pink lichen giber, syphilitic roseola, with a prolonged course of pigmentation observed after the resolution of various skin diseases, in the presence of depigmented spots with syphilitic leukoderma, as well as dry streptoderma.
Treatment. Currently, the arsenal has a sufficient selection of topical antimycotic drugs that have a pronounced antifungal effect against the causative agent of multicolored lichen. These include imidazole and triazole derivatives, allylamine compounds. Use: ketoconazole cream, oxyconazole cream, cream and clotrimazole solution, bifonazole cream (prescribed 1 time per day for 2-3 weeks); econazole cream (prescribed 2 times a day for 3-4 weeks); terbinafine cream and spray, exifin cream (applied to cleaned and dried lesions 2 times a day for 7-14 days, if necessary, after a 2-week break, the treatment can be repeated). With common, often recurring forms of multicolored lichen, antimycotics of a systemic effect (itraconazole, fluconazole) are more effective.
Prevention Disinfection of underwear and bed linen during the treatment period and prophylactic treatment courses 1-2 months after the end of treatment, using the same drugs as for treatment, but using them for 7-10 days.
Mycosis of smooth skin of the feet (hands)
In some countries, foot mycosis affects up to 50% of the population. The disease is more common in adults, but in recent years it has often been observed in children, even infants.
Etiology. The main causative agent of mycosis of the feet is the fungus Trichophyton rubrum (T. rubrum), which is secreted up to 90%, then T. mentagrophytes var. interdigitale (T. interdigitale). The defeat of the interdigital folds may be due to yeast-like fungi (from 2 to 5% of cases). The anthropophilic fungus Epidermophyton floccosum is rarely isolated in our country.
Epidemiology. Infection with foot mycosis is possible in the family in close contact with the patient or through household items, in a bathhouse, sauna, gym, when using other people’s shoes and clothes.
Pathogenesis. The penetration of fungi into the skin is facilitated by cracks, abrasions in the interdigital folds, due to sweating or dry skin, abrasion, poor drying after water procedures, narrow interdigital depots, flat feet, etc.
Clinical manifestations on the skin depend on the type of pathogen, the general condition of the patient.
Mycosis of the feet (hands) caused by
T. rubrum (trichophytosis)
The T.rubrum fungus can cause damage to the skin of all interdigital folds, soles, palms, the dorsum of the feet and hands, lower legs, thighs, inguinal-femoral, intergluteal folds, under the mammary glands and axillary region, trunk, face, and rarely the scalp. The process can involve fluffy and long hair, nail plates of the feet and hands.
With lesions of the skin of the feet, 3 clinical forms are distinguished: squamous, intertriginous, squamous-hyperkeratotic.
The squamous form is characterized by the presence of peeling on the skin of the interdigital folds, soles, palms. It can be flour-shaped, ring-shaped, lamellar. In the area of the arches of the feet and palms, an increase in the skin pattern is observed.
Intertriginous form is most common and is characterized by slight redness and peeling on the lateral contacting surfaces of the fingers or maceration, the presence of erosion, superficial or deep cracks in all folds of the feet. This form can be transformed into dyshidrotic, in which bubbles or bubbles form in the area of the arches, along the outer and inner edges of the feet and in the interdigital folds. The superficial vesicles open with the formation of erosion, which can merge, resulting in the formation of lesions with clear boundaries, weeping (see. Fig. On the color inset, p. 198). When a bacterial infection is attached, pustules, lymphadenitis and lymphangitis occur. With the dyshidrotic form of mycosis, secondary allergic rashes are observed on the lateral and palmar surfaces of the fingers of the hands, palms, forearms, legs. Sometimes the disease acquires a chronic course with exacerbation in the spring and summer.
Squamous-hyperkeratotic form is characterized by the development of foci of hyperkeratosis on the background of desquamation. The skin of the soles (palms) becomes a reddish-cyanotic color, pityriasis peeling is noted in the skin grooves, which passes to the plantar and palmar surfaces of the fingers. On the palms and soles there may be pronounced annular and lamellar peeling. In some patients, it is insignificant due to frequent hand washing.
In children, damage to the smooth skin on the feet is characterized by small-plate peeling on the inner surface of the terminal phalanges of the fingers, often III and IV, or there are superficial, rarely deep cracks, mainly in the III and IV interdigital folds or under the fingers, hyperemia and maceration. On the soles of the skin, the skin pattern may not be changed or the skin pattern may be strengthened, ring peeling is sometimes observed. Subjectively sick, itching. In children, more often than in adults, exudative forms of lesion occur with the formation of vesicles, weeping, eczema-like foci. They appear not only on the feet, but also on the hands.
For rubrophytia of smooth skin of large folds and other areas of the skin, a characteristic feature is the development of foci with clear boundaries, irregular outlines, an intermittent ridge along the periphery, consisting of merged pink nodules, scales and crusts, with a bluish tint, the color in the center is bluish-pink. On the extensor surface of the forearms, lower legs, rashes can be located in the form of open rings. Often there are foci with nodular and nodular elements. The disease sometimes proceeds as an infiltrative suppurative trichophytosis, more often in men with localization in the chin area and above the upper lip. Foci of rubrophytes on smooth skin can resemble psoriasis, lupus erythematosus, eczema and other dermatoses.
Mycosis of the feet due to T. interdigitale
Mushroom T. interdigitale affects the skin of the III and IV interdigital folds, the upper third of the sole, the lateral surfaces of the foot and fingers, and the arch of the foot. It has pronounced allergenic properties.
With foot mycosis due to T. interdigitale, the same clinical forms of lesion are observed as with rubrophytia, however, the disease often proceeds with more pronounced inflammatory phenomena. With a dyshidrotic, less often intertriginous form, large blisters may appear on the skin of the soles and fingers along with small vesicles in the case of the attachment of bacterial flora with purulent contents. The foot becomes swollen, swollen, pain when walking. The disease is accompanied by fever, poor health, the development of allergic rashes on the skin of the upper and lower extremities, trunk, face, enlarged inguinal lymph nodes, the clinical picture is similar to eczema.
Diagnosis and differential diagnosis. The diagnosis is established on the basis of clinical manifestations, detection of the fungus by microscopic examination of skin flakes and the possibility of identifying the type of pathogen in a culture study.
Mycosis of the feet (palms) must be differentiated from dyshidrotic eczema, psoriasis, pustular Andrews bactericide, keratoderma, as well as with the localization of foci: on the legs – from nodular vasculitis, papulonecrotic tuberculosis, limited neurodermatitis; on the skin of the body – from psoriasis, superficial and chronic trichophytosis, infiltrative and infiltrative suppurative forms of zooanthroponous trichophytosis, inguinal epidermophytosis; on the face – from lupus erythematosus.
Treatment. Treatment of mycosis of smooth skin of the feet and other localizations is carried out with antimycotic agents for external use. With squamous and intertriginous forms of lesions on the feet and other parts of the skin, drugs are used in the form of a cream, ointment, solution, spray, you can combine a cream or ointment with a solution, alternating them. Medicines that are currently used include: ketoconazole cream, oxyconazole cream, clotrimazole cream and solution, bifonazole cream, naftifine cream and solution, cream and terbinafine spray. These preparations are applied to cleansed and dried skin once a day, the duration of treatment is on average up to 2 weeks. Antimycotics isoconazole, econazole, cyclopirox, undecylenic acid + undecylenic acid zinc salt, miconazole + mazipredone are used 2 times a day until clinical manifestations are resolved, then treatment is continued for another 1-2 weeks, but once a day to prevent relapse. In case of nodular and nodular forms of rubrophytia, after removal of acute inflammatory phenomena, one of the indicated ointments is prescribed sulfur-tar ointment (5-10%) for further resolution of clinical manifestations. With intertriginous and dyshidrotic forms (the presence of only small vesicles) of mycosis of the feet, drugs with a combined effect are used, which along with an antifungal agent include a corticosteroid – isoconazole + diflucortolone-21-valernate, miconazole + mazipredone; corticosteroid and antibacterial drug – hydrocortisone + natamycin + neomycin, naftifin, betamethasone + clotrimazole + gentamicin.
In acute inflammatory conditions (weeping, the presence of blisters) and severe itching, treatment is carried out as in eczema: desensitizing agents (intravenous administration of calcium chloride solution (10%), sodium thiosulfate solution (30%), calcium gluconate solution (10%) or calcium pantothenate orally; antihistamines. Of the external drugs at the first stage of therapy, lotions are used (2% boric acid solution, potassium permanganate solution 1: 6000, 0.5% resorcinol solution), 1-2% aqueous solutions of methylene blue or brilliant green, fucorcin . Then, moving to a paste – boric naftalan, ichthyol-naftalan, ACD paste – F3 with naftalan, at complication of bacterial flora – linkomitsinovuyu (2%) in the second stage of treatment after resolution of acute inflammation using listed antimycotic agents..
when infiltrative-suppurative in the form of rubrophytia, the treatment is carried out as with zooanthroponous trichophytosis.First, the crusts in the lesion are removed oia, applying dressings with salicylic ointment (2%) under the compress for several hours, hair is epilated. Then, lotions with furacilin 1: 5000, rivanol 1: 1000, potassium permanganate 1: 6000 are used on the foci. Subsequently, a resolving sulfur-tar ointment (5-10%) is prescribed by rubbing or under compress paper. After resolving the infiltrate, undecylenic acid ointment + undecylenic acid zinc salt, clotrimazole cream, cyclopirox, oxyconazole and others are used until the clinical manifestations are completely resolved.
With the ineffectiveness of external therapy, antimycotics of systemic action are prescribed.
Prevention To prevent infection of foot mycosis, it is necessary to first observe the rules of personal hygiene in the family, as well as when visiting a bathhouse, sauna, pool, gym, etc .; disinfection of shoes (gloves) and linen during the treatment period.
Superficial candidiasis of the skin
Superficial skin candidiasis is a fungal disease caused by yeast-like fungi of the genus Candida.
Etiology. Pathogens belong to opportunistic fungi, which are widespread in the environment. They can also be found on the skin and mucous membrane of the mouth, digestive tract, genitalia of a healthy person.
Epidemiology. Infection from the external environment can occur with constant fractional or massive infection with fungi.
Pathogenesis. The emergence of candidiasis can contribute to both endogenous and exogenous factors. Endogenous factors include endocrine disorders, more often diabetes mellitus, immune deficiency, severe somatic diseases and a number of others. The disease develops in premature babies and receiving broad-spectrum antibacterial drugs.
Frequent contact with water contributes to the development of candidiasis in the interdigital folds of the hands, as maceration of the skin develops, which is a favorable environment for the introduction of the pathogen from the external environment.
Clinic. On smooth skin, small folds on the hands and feet are more often affected, less often large ones (inguinal-femoral (see. Fig. On the color insert, page 198), axillary, under the mammary glands, intergluteal). Foci outside the folds are located mainly in patients suffering from diabetes mellitus, severe general diseases, and infants.
In some folds of the skin in some patients, the disease begins with the formation of small, barely noticeable vesicles on the lateral contacting surfaces of the hyperemic skin, the process gradually spreads to the fold area, then peeling, maceration or immediately eroded surfaces of a deep red color appear with a shiny, as if varnished surface, clear boundaries, with peeling of the stratum corneum of the epidermis on the periphery. More often the III and IV interdigital folds on one or both hands are affected. The disease is accompanied by itching, burning, sometimes soreness. The course is chronic with frequent relapses.
In large folds of skin, small bubbles or pustules appear with a pinhead, which quickly open, erosion is formed in their place, rapidly increasing in size, merging with each other. The lesion foci occupy a significant surface, have clear boundaries, irregular outlines, dark red, shiny, with a moist surface, a strip of exfoliating stratum corneum of the epidermis. Around large foci, new small erosions arise. In children, the process of large folds can extend to the skin of the thighs, buttocks, abdomen, trunk. Painful cracks sometimes form in the depths of the folds.
Candidiasis of smooth skin outside the folds has a similar clinical picture.
One of the clinical forms of smooth skin candidiasis is candidiasis of the nipples in nursing women. Clinical manifestations may be different: in the area of the perosseous circle there is a small focus of hyperemia, covered with white scales; focus near the nipple with clear boundaries, maceration; there is a crack between the nipple and the nasal circle with maceration along the periphery, small bubbles.
Diagnosis and differential diagnosis. The diagnosis is made on the basis of a typical clinic, detection of the fungus in scraping with skin flakes under a microscopic examination. Candidiasis of large folds is differentiated from seborrheic eczema, psoriasis; small folds on the hands – from dyshidrotic eczema; on the feet – from mycosis caused by T. interdigitale and T. rubrum, dyshidrotic eczema; smooth skin without folds – from eczema, other fungal diseases: rubrophytia, superficial trichophytosis, pseudomycosis – erythrasma.
Treatment. Limited, sometimes widespread acute forms of smooth skin lesion, especially those developed during treatment with antibacterial drugs, are usually easily treatable with local antimycotics in the form of a solution, cream, ointment and can be resolved even without treatment after antibiotic withdrawal.
In case of candidiasis of smooth skin of large folds with acute inflammatory phenomena, treatment should be started with the use of an aqueous solution of methylene blue or brilliant green (1-2%) in combination with an indifferent powder and carried out for 2-3 days, then apply antimycotic drugs until clinical symptoms are resolved .
Of the antimycotic agents for smooth skin candidiasis, use: clotrimazole solution and cream, oxyconazole cream, bifonazole cream, natamycin and hydrocortisone + natamycin + neomycin, naphthifin, isoconazole + diflucortolone-21-vernate and isoconazole, ketoconazole cream, ecoconazole cream, ecoconazole cream powder.
With common processes on the skin in case of ineffective local therapy, systemic antimycotics are prescribed (fluconazole, itraconazole).
Prevention Prevention of candidiasis of smooth skin in adults and children is to prevent its development in patients suffering from background diseases, as well as in individuals who have been receiving antibacterial, corticosteroid, immunosuppressive therapy for a long time.