Microsporia is a fungal disease that affects the skin and hair, and in extremely rare cases, and nail plate. The name of this fungal disease comes from the name of its causative agent – a fungus of the Microsporum genus . The disease is also known as “ringworm”, due to the peculiarities of its manifestation.
Once on the skin, the fungus is embedded in it and begins to multiply. When located near the hair follicles, spores of the fungus germinate, resulting in damage to the hair. Quite quickly spreading over the surface of the hair, the fungus destroys the cuticle, between the scales of which spores accumulate. Thus, the mushroom surrounds the hair, forming a cover, and fills the bulb tightly.
Microsporia is the most common fungal infection, not counting the foot fungus. The disease is ubiquitous. Microsporia is highly contagious, children are more likely to suffer. Adults rarely get sick – mostly young women. The rarity of the microsporia disease in adults, especially with damage to the scalp, and the usually self-recuperating at the beginning of adolescence is due to the presence of organic acids in the hair of adults that slow down the growth of the fungus.
The main source of the disease is cats (usually kittens), less often dogs. Infection with microsporia occurs through direct contact with a sick animal or objects infected with wool or scales. Once in the soil, the fungus maintains vitality only for 1-3 months. Thus, the soil is only a factor of transmission and does not serve as its natural source.
Manifestations of microsporia in animals are characterized by areas of baldness on the face, outer surfaces of auricles, as well as on the front, less often the hind, legs. Often outwardly healthy cats can be carriers of the fungus.
Seasonal variations in morbidity are associated with offspring in cats, as well as more frequent contact of children with animals in the summer. The rise in the incidence of microsporia begins at the end of summer, the peak occurs in October – November, and the decline to a minimum occurs in March – April.
The incubation period for zoonotic microsporia is 5-7 days. The nature of the manifestations of microsporia is due to the location of the lesions and the depth of penetration of the pathogen.
Microsporia of smooth skin and microsporia of the scalp are distinguished.
Microsporia smooth skin
At the site of the introduction of the fungus, an edematous, towering red spot appears with clear boundaries. Gradually the stain increases in diameter. Along the edge, a continuous towering roller is formed, represented by small nodules, bubbles and crusts. In the central part of the spot, the resolution of inflammation occurs, as a result of which it acquires a pale pink color, with scaly peeling on the surface. Thus, the focus has the form of a ring.
The number of lesions with microsporia smooth skin is usually small (1–3). Their diameter ranges from 0.5 to 3 cm. Most often the lesions are located on the skin of the face, neck, forearms and shoulders. There is no subjective sensation or mild itching.
In infants and young children, as well as in young women, marked inflammation and minimal flaking are often observed.
In individuals prone to allergic reactions (in particular, in patients with atopic dermatitis), the fungus is often masked by manifestations of the main process and is not always diagnosed in a timely manner. The use of local hormonal drugs only increases the spread of the fungal infection.
A rare variety of microsporia should include damage to the skin of the palms, soles and nail plates. For the defeat of the nail is characterized by an isolated lesion of the nail plate, usually its outer edge. Initially, a dim stain forms, acquiring a white color over time. The whitening nail becomes softer and more fragile, and may subsequently collapse.
The defeat of the scalp microsporia occurs mainly in children 5-12 years. It is believed that the rarity of this form in adults is due to the presence in their hair of organic acids that slow down the growth of the fungus. This fact indirectly confirms the independent recovery of children at puberty, when there is a change in the composition of sebum. Interestingly, microsporia of the scalp is almost not found in children with red hair.
The foci of microsporia of the scalp are located mainly on the crown, in the parietal and temporal areas. Usually there are 1–2 large foci ranging in size from 2 to 5 cm, with rounded or oval contours and clear boundaries. On the edge of large foci, there may be screenings – small foci with a diameter of 0.5-1.5 cm. At the beginning of the disease, a peeling area is formed at the site of infection. In the early days, the mushroom is located only at the mouth of the hair follicle. On closer examination, you can see a whitish annular scale surrounding the hair like a cuff. On the 6th – 7th day, microsporia extends to the hair itself, which becomes brittle, breaks off over the surrounding skin by 4–6 mm and looks as if trimmed (hence the name “ringworm”). The remaining hemp looks dull, covered with a grayish-white cap, which is a spore of the fungus. If hemp “stroke”, they deviate in one direction and, unlike healthy hair, do not restore their original position. The skin in the lesion, as a rule, slightly reddened, swollen, its surface is covered with grayish-white small scales.
photo: microsporia scalp
Photo: Site of the Department of Dermatology and Venereology of the Tomsk Military Medical Institute
With the suppurative form of microsporia on the background of significant inflammation, soft bluish-red nodes are formed, the surface of which is covered with abscesses. When pressed through the holes, pus is secreted. Irrational (usually local) therapy, the presence of serious concomitant diseases, and a late visit to a doctor contribute to the formation of the suppurative form of microsporia.
Diagnosis of microsporia is carried out by a dermatologist.
To confirm the diagnosis of microsporia used fluorescent, microscopic and cultural studies.
Luminescent examination: the method is based on identifying a bright green glow of hair affected by fungi of the Microsporum genus during examination under the Wood lamp. The reason for this phenomenon has not yet been established. Fluorescent examination should be carried out in a darkened room. Lesions pre-cleaned of crusts, ointments, etc. When examining fresh foci, the luminescence may be absent, which is associated with insufficient damage to the hair. In such situations, hair should be removed from the intended place of introduction of the fungus, and the glow can be found in their root part. With the death of the fungus glow in the hair is preserved.
The luminescent method serves for:
- determination of the pathogen;
- definitions of affected hair;
- evaluation of the results of therapy;
- control of persons in contact with the patient;
- determination of infection or carriage in animals
Microscopic examination: to confirm the fungal origin of the disease, microscopic examination is applied to flakes from lesions with lesions of smooth skin, and with involvement of the scalp in the process – fragments of hair. In flakes from lesions on smooth skin, convoluted mycelium filaments are found. Microscopic examination of the affected hair reveals many small spores on its surface.
Cultural research: culture diagnostics with positive results of luminescent and microscopic studies are required to identify the causative fungus. The method allows to determine the type and type of pathogen and, consequently, to carry out adequate therapy and prevention of the disease. Material (scales, hair) is placed on a nutrient medium. The growth of the microsporum colonies (the main causative agent of microsporia) is noted on the 3rd day after seeding.
Treatment of microsporia smooth skin
In the treatment of microsporia smooth skin without damaging the hair, external antifungal drugs are used. 2–5% iodine tincture is applied to the lesions in the morning, and in the evening they are smeared with antifungal ointment. Use traditional 10–20% sulfuric acid, 10% sulfur-3% salicylic or 10% sulfur-tar ointment. Modern ointments are applied twice a day:
- bifonazole and others.
The drug terbinafine ( lamisil ), produced in the form of 1% cream and spray, has proven itself well .
In severe inflammation, it is advisable to prescribe a combination of drugs that contain additional hormones. Such means include ointment mikozolon and travokort.
When joining a bacterial infection, triderm cream is useful . With deep forms of microsporia, preparations containing dimexide are shown . In particular, in such situations a 10% solution of chinosol is widely used (chinosol and salicylic acid, 10.0 each, dimexide 72.0, distilled water 8.0). The solution should be applied 2 times a day until the fungi disappear.
With the defeat of gun , and especially longer hair, it is necessary to conduct a systemic antifungal therapy of microsporia.
Treatment of microsporia of the scalp
In the treatment of this form of the disease, griseofulvin , an antibiotic produced by mold fungi, is still the drug of choice . Griseofulvin , produced in the form of tablets of 125 mg. The drug is taken daily in 3-4 doses with meals with a teaspoon of vegetable oil, which is necessary to increase the solubility ofgriseofulvin and increase the duration of its action. Children under the age of 3 should preferably be given griseofulvin as a suspension, 8.3 ml of which correspond to 1 tablet (125 mg) of the drug. Continuous therapy is carried out until the first negative test result for mushrooms, after which griseofulvin is taken in the same dose every other day for 2 weeks, and then another 2 weeks 2 times a week. The general course of treatment is 1.5–2 months.
In the course of treatment, it is necessary to shave off hair and wash your hair 2 times a week. It is recommended to rub at the hearth any antifungal ointment at the same time. In parallel with the reception of the antifungal drug, it is possible to carry out manual hair removal with a preliminary imposition of a 5%griseofulvin patch on the lesion.
Of the side effects of griseofulvina should be noted headache, allergic rashes, discomfort in the pancreas. Because of the toxic effects on the liver, griseofulvin is contraindicated in children who have had hepatitis or suffer from liver diseases. The drug is also not prescribed for kidney disease, gastric ulcer and duodenal ulcer, neuritis, blood diseases, photodermatosis.
In recent years, terbinafine ( lamisil ) serves as an alternative to griseofulvin . In the treatment of microsporia of the scalp, terbinafine is used in the form of tablets produced in doses of 125 and 250 mg. When treating children, the dose of terbinafine is established depending on body weight. Terbinafin take 1 time per day. Tolerability is good. Patients may be disturbed by a feeling of fullness in the stomach, minor abdominal pain. Compliance with a diet aimed at stopping meteorism, relieves patients from unpleasant sensations.
Prevention of microsporia is the timely detection, isolation and treatment of patients with microsporia. Periodic medical examinations should be carried out in institutions. The identified patient with microsporia of a child must be isolated from other children and sent for treatment to a specialized hospital. The things belonging to the patient are subject to disinfection.
Relatives and persons who came in contact with patients are examined. Special attention should be paid to domestic animals, since they are often the source of infection. Patients with microsporia animals are either destroyed or they receive a full-fledged antifungal treatment.