Candidiasis

Candidiasis - it antropos mycosis characterized by lesions of the mucous membranes and skin. There is usually endogenously. Main agents - yeast-like fungi of the genus Candida family Cryptococcaceae class Deuteromycetes. Lesions in humans are caused by C. albicans (more than 90% of lesions), C. tropicalis, C. krusei, C. lusitaniae, C. parapsilosis, C. kefyr, C. guilliermondii, and others. C. albicans - a normal commensal of the oral cavity. Any violation of resistance of the organism or changes the normal microbial coenosis may lead to the development of the disease.

Candida not refer to the true dimorphic fungus, as in tissues can be identified as yeast cells and hyphae. In the mycelial phase transition can be observed by culturing at a low temperature (22-250S) or depleted medium. Transition phase in the yeast mycelium (mold) in vivo can be observed during germination in the tissues of the body.

Yeast phase is represented by an oval or round cells blastospores (4-8 microns), breeding multipolar budding (see Fig. 6). The cell wall contains 5-7 layers. The optimum temperature for growth of 25-280 C.

Mycelial phase consists of chains of elongated cells with a three-layer cell wall, forming pseudomycelium (see Fig. 7). On it are arranged randomly yeast blastospores (kidney). Some species, including C. albicans, form the terminal hlamidiospory (enlarged hyphal cells with thick shell).

The pathogenesis of lesions. Pathogenicity factors are still poorly understood. At Candida identified adhesin (cause adhesion to the epithelium), hemolysin, oligosaccharides cell wall (inhibit cell-mediated immune response), phospholipase and acidic protease endotoxin. Also, candida can mask the surface structures, which interact with complement components and opsonins.

The most common form of oral candidiasis - pseudomembranous candidiasis (thrush). Is more common in neonates (premature, birth traumas) or in adults with immunodeficiency. Originally areas of mucous membranes become darker and shiny ("patent mucous"), then they appear white or yellowish or creamy "cheesy" plaques that may coalesce to form large areas of lesions (hence the "thrush"). Plaques can be localized on the tongue, soft palate and firm, gums, cheeks, tonsils, pharynx (see Fig. 28-30). Plaques can be easily removed, leaving bleeding erosion. With the localization of lesions in the language of patients complain of change in taste or increased sensitivity to spicy or hot food. Defeat is often associated with diffuse erythema and increased dryness of mucous membranes. In severe immune deficiency affected almost all of the oral mucosa, tonsils, pharynx, esophagus, stomach, bronchi and lungs.

Chronic candidiasis - develops as a result of wearing dentures or pathology mediated by defects in T lymphocytes. Manifest lesions of the skin and oral mucosa in the form of cheilitis, perleches, glossitis.

Hyperplastic candidiasis - white mucous formed confluent papules. Considered as a precancerous condition.

Microbiological diagnosis. Microscopic technique. Take a scraping from the mucosa, make a smear on a glass slide. Mikroskopiruyut unstained preparations and preparations treated with KOH, stained by Gram Romanovsky-Giemsa, methylene blue. In the diagnosis is based on detection of the fungus elements: single budding cells pseudomycelium other morphological structures (blastokonidii, pseudohyphae).

Mycological method. Seeded material on Wednesday Saburo, blood or serum agar. Optimal cultivation temperature - 30-37 ° C, pH - 6.0-6.8. On rice agar make sparse crop. Above the plating applied coverslip leave culture at 18-48 h at room temperature, after which mikroskopiruyut a phase contrast microscope or with lowered condenser. Assess the shape and location of pseudohyphae psevdokonidy along pseudohyphae. Colonies of C. albicans on Sabouraud agar round, whitish-cream (lat. Candidus - snow-white), convex, shiny, with smooth edges, reminiscent of a drop of mayonnaise. Hallmarks of C. albicans is considered:

- Ability to ferment glucose and maltose with production of acid and gas;

- With growth in liquid protein media at 37 ° C after 2-4 hours blastospores vast majority of strains form a special outgrowths - growth tube. Strains which do not form them avirulent;

- By culturing at 22-25 ° C or at least depletion of glucose in the medium (4-7 days) or "hungry" media forms hlamidiospory C. albicans.

Diagnostic value in the detection of candidiasis is fungal CFU and the multiplicity detection.

Skin-allergic method - put a test with Candida allergen.

Important in the diagnosis of mycosis belongs tsitogistologicheskim ways to determine the infestation of the fungus in the host tissue.

Treatment. For specific antifungal treatment mucocutaneous candidiasis forms used antifungals (nystatin, natamycin, levorin, Amphoglucaminum, miconazole). Mechanism of action is associated with their effect on the main enzymes involved in the biosynthesis of ergosterol, a component of the cell membrane of the fungus, but the level of impact is different.

Specific prevention. Currently using killed vaccines. Vaccine derived from autostrains, conduct anti-treatment of chronic candidiasis.

Necrotizing ulcerative gingivostomatitis Vincent

(fuzospirohetoz)

Fuzospirohetoz - an acute inflammation of the gums with pronounced symptoms of alteration. The etiology and pathogenesis of this disease are not fully disclosed. Necrotizing ulcerative gingivitis develops against the background of catarrh. This disease occurs mainly in young adults, as a result of SARS, sore throat, flu, hypothermia, stress, malnutrition, hypovitaminosis reduced immunity. Against this background, the conditions for increasing the amount of flora and enhancing its pathogenicity. Among anaerobic microorganisms predominate form - fuzobakterii (Fusobacterium plautii), spirochetes (Treponema vincentii). Often precedes the development of the disease the inflammation caused by staphylococci and streptococci. Pathogenetic value fusiform bacteria associated with the presence of enzymes gistoliticheskih type collagenase proteinase hyaluronidase which cause degradation of connective tissue. In this case, the low molecular weight nitrogen-containing products formed as a result of the collapse of collagen, can be assimilated by spirochetes. Anaerobic conditions created in the necrotic tissue due to oxygen inactivates the action of bacterial enzymes catalase and superoxide dismutase, prevent rapid recovery and contribute to further tissue damage. As a result, significant necrosis of the gums, the deformation of the gingival margin and creates a potential hotbed of chronic inflammation in the periodontium. Furthermore, during the life of secreted bacterial fatty acids as well as enzymes and enzyme gistoliticheskie Ig A protease suppress immunity of mucous membranes of the mouth, causing degradation of the immunoglobulins, complement. Together with fusiform bacteria in inflammation develop other anaerobes: Bacteroides, peptokokki, peptostreptokokkov, veylonelly.

Development of necrotizing gingivitis Vincent promotes bad individual oral hygiene, dental plaque, the presence of caries, decayed teeth, shortness eruption of wisdom teeth (the presence of "the hood"). The patient complains of pain in the gums, which makes it difficult eating and talking. In a study of congestion is determined, the presence of ulceration and necrosis of the gums (gray patina), a significant amount of soft plaque and hard dental plaque, there is halitosis. Often observe the defeat of the tonsils and the larynx with the development of a condition known as angina Simanovskiy-Vincent-Plaut.

Laboratory diagnosis. In the diagnosis of disease play a significant role additional studies: complete blood count, cytological examination. To confirm the diagnosis is of great importance bacteriascopical study when detected coccal flora but dominated fuzobakterii spirochetes.

Treatment. Carried out taking into account the general and dental status. Treated comprehensively with local effects (conservative, surgical, orthopedic and physiotherapy techniques) and the strengthening therapy with the use of vitamins. In severe forms of the disease prescribe antibiotics.